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BACKGROUND: The most aggressive form of breast cancer is triple-negative breast cancer (TNBC), which lacks expression of the estrogen receptor (ER) and progesterone receptor (PR), and does not have overexpression of the human epidermal growth factor receptor 2 (HER2). Treatment options for women with TNBC tumors are limited, unlike those with ER-positive tumors that can be treated with hormone therapy, or those with HER2-positive tumors that can be treated with anti-HER2 therapy. Therefore, we have sought to identify novel targeted therapies for TNBC. In this study, we investigated the potential of a novel phosphatase, NUDT5, as a potential therapeutic target for TNBC. METHODS: The mRNA expression levels of NUDT5 in breast cancers were investigated using TCGA and METABRIC (Curtis) datasets. NUDT5 ablation was achieved through siRNA targeting and NUDT5 inhibition with the small molecule inhibitor TH5427. Xenograft TNBC animal models were employed to assess the effect of NUDT5 inhibition on in vivo tumor growth. Proliferation, death, and DNA replication assays were conducted to investigate the cellular biological effects of NUDT5 loss or inhibition. The accumulation of 8-oxo-guanine (8-oxoG) and the induction of γH2AX after NUDT5 loss was determined by immunofluorescence staining. The impact of NUDT5 loss on replication fork was assessed by measuring DNA fiber length. RESULTS: In this study, we demonstrated the significant role of an overexpressed phosphatase, NUDT5, in regulating oxidative DNA damage in TNBCs. Our findings indicate that loss of NUDT5 results in suppressed growth of TNBC both in vitro and in vivo. This growth inhibition is not attributed to cell death, but rather to the suppression of proliferation. The loss or inhibition of NUDT5 led to an increase in the oxidative DNA lesion 8-oxoG, and triggered the DNA damage response in the nucleus. The interference with DNA replication ultimately inhibited proliferation. CONCLUSIONS: NUDT5 plays a crucial role in preventing oxidative DNA damage in TNBC cells. The loss or inhibition of NUDT5 significantly suppresses the growth of TNBCs. These biological and mechanistic studies provide the groundwork for future research and the potential development of NUDT5 inhibitors as a promising therapeutic approach for TNBC patients.

Manuka honey (MH) exhibits potential antitumor activity in preclinical models of a number of human cancers. Treatment in vitro with MH at concentrations ranging from 0.3 to 5.0% (w/v) led to significant dose-dependent inhibition of proliferation of human breast cancer MCF-7 cells, but anti-proliferative effects of MH were less pronounced in MDA-MB-231 breast cancer cells. Effects of MH were also tested on non-malignant human mammary epithelial cells (HMECs) at 2.5% w/v, and it was found that MH reduced the proliferation of MCF-7 cells but not that of HMECs. Notably, the antitumor activity of MH was in the range of that exerted by treatment of MCF-7 cells with the antiestrogen tamoxifen. Further, MH treatment stimulated apoptosis of MCF-7 cells in vitro, with most cells exhibiting acute and significant levels of apoptosis that correlated with PARP activation. Additionally, the effects of MH induced the activation of AMPK and inhibition of AKT/mTOR downstream signaling. Treatment of MCF7 cells with increased concentrations of MH induced AMPK phosphorylation in a dose-dependent manner that was accompanied by inhibition of phosphorylation of AKT and mTOR downstream effector protein S6. In addition, MH reduced phosphorylated STAT3 levels in vitro, which may correlate with MH and AMPK-mediated anti-inflammatory properties. Further, in vivo, MH administered alone significantly inhibited the growth of established MCF-7 tumors in nude mice by 84%, resulting in an observable reduction in tumor volume. Our findings highlight the need for further research into the use of natural compounds, such as MH, for antitumor efficacy and potential chemoprevention and investigation of molecular pathways underlying these actions.

Breast cancer (BC) remains among the most commonly diagnosed cancers in women worldwide. Triple-negative BC (TNBC) is a subset of BC characterized by aggressive behavior, a high risk of distant recurrence, and poor overall survival rates. Chemotherapy is the backbone for treatment in patients with TNBC, but outcomes remain poor compared to other BC subtypes, in part due to the lack of recognized functional targets. In this study, the expression of the tetraspan protein epithelial membrane protein 2 (EMP2) was explored as a predictor of TNBC response to standard chemotherapy. We demonstrate that EMP2 functions as a prognostic biomarker for patients treated with taxane-based chemotherapy, with high expression at both transcriptomic and protein levels following treatment correlating with poor overall survival. Moreover, we show that targeting EMP2 in combination with docetaxel reduces tumor load in syngeneic and xenograft models of TNBC. These results provide support for the prognostic and therapeutic potential of this tetraspan protein, suggesting that anti-EMP2 therapy may be beneficial for the treatment of select chemotherapy-resistant TNBC tumors.

Triple-negative breast cancer (TNBC) is highly aggressive with limited available treatments. Stromal cells in the tumor microenvironment (TME) are crucial in TNBC progression; however, understanding the molecular basis of stromal cell activation and tumor-stromal crosstalk in TNBC is limited. To investigate therapeutic targets in the TNBC stromal niche, we used an advanced human in vitro microphysiological system called the vascularized micro-tumor (VMT). Using single-cell RNA sequencing, we revealed that normal breast tissue stromal cells activate neoplastic signaling pathways in the TNBC TME. By comparing interactions in VMTs with clinical data, we identified therapeutic targets at the tumor-stromal interface with potential clinical significance. Combining treatments targeting Tie2 signaling with paclitaxel resulted in vessel normalization and increased efficacy of paclitaxel in the TNBC VMT. Dual inhibition of HER3 and Akt also showed efficacy against TNBC. These data demonstrate the potential of inducing a favorable TME as a targeted therapeutic approach in TNBC.

Background: Triple-negative breast cancer (TNBC) is characterized by high invasiveness and metastasis potential. Ubiquitin carboxy-terminal hydrolase L1 (UCHL1) is strongly associated with breast cancer progression, although the underlying mechanisms are largely unknown. Methods: The gene expression profiles of TNBC samples were downloaded from the TCGA database, and ubiquitination enzymes related to immune regulation were screened. UCHL1 expression in the TNBC tissues and in adipose-derived mesenchymal stem cells (ADSCs) stimulated in vitro with pro-inflammatory cytokines were analyzed. Exosomes were isolated from these stimulated ADSCs and transfected with scrambled (si-NC) or UCHL1-specific (si-UCHL1) siRNA constructs. TNBC cells were treated with the ADSCs-derived exosomes (ADSCs-Exos) and then co-cultured with macrophages or T cells. Finally, the tumorigenic potential of the ADSCs-Exos was evaluated by injecting the exosomes into mice bearing TNBC xenografts. Results: UCHL1 was highly expressed in TNBC tissues and the stimulated ADSCs. The exosomes derived from stimulated ADSCs increased the viability and migration capacity of TNBC cells in vitro, and significantly increased Ki-67 expression through UCHL1. Furthermore, ADSCs-Exos induced M2 polarization of THP-1 monocytes by upregulating CD206 and Arg-1, and downregulating TNF-α and iNOS, and also decreased the proportion of CD3+CD8+ T cells. Mechanistically, UCHL1 regulated the STAT3 and PD-L1 signaling pathways through HDAC6. Exosomes derived from the control and cytokine-stimulated ADSCs also promoted tumor growth in vivo, and increased the expression of UCHL1, CD206, HDAC6, STAT3, and PD-L1. However, UCHL1 knockdown reversed the pro-tumorigenic effects of the ADSCs-derived exosomes in vivo and in vitro. Conclusion: Pro-inflammatory factors (IFN-γ + TNF-α) stimulating ADSCs-Exos enhance immune evasion in triple-negative breast cancer by regulating the HDAC6/STAT3/PD-L1 pathway via UCHL1 transporter. Thus, UCHL1 inhibition may enhance the response of TNBC to immunotherapy. [ABSTRACT FROM AUTHOR]

We report the synthesis, characterization, anti-cancer activity and mechanism of action of a novel water-soluble Cu(II) complex with salicylidene carbohydrazide as the ligand and o-phenanthroline as the co-ligand. The synthesized complex (1) was characterized by FT-IR, EPR, and electronic spectroscopy, as well as single crystal X-ray diffraction. This compound was found to be paramagnetic from EPR spectra and X-ray crystallography revealed that the molecule crystallized in an orthorhombic crystal system. The crystal lattice was asymmetric containing two distinct binuclear copper complexes containing the Schiff base as the major ligand, o-phenanthroline as a co-ligand, two nitrate anions, and two water molecules. The Cu(II) in the first site coordinated with the enolised ligand comprising enolate O-, phenolate O-, and the imine N and N,N from o-phen. The major part of this complex exists as Cu(II) coordinated with two H2O molecules at the second site with nitrate acting as the counter anion. However, a smaller portion of the complex exists where Cu(II) is coordinated with NO3- and H2O, and the remaining water molecule acts as lattice water. It was tested for DNA binding and cleavage properties which revealed that it binds in an intercalative mode to CT-DNA with Kb value of 1.25 x 104 M-1. Furthermore, cleavage studies reveal that the complex has potential for efficient DNA cleavage under both oxidative and hydrolytic conditions. It was able to enhance the rate of cleavage by 2.8 x 108 times. The complex shows good cytotoxicity to breast cancer monolayer (2D) as well as spheroid (3D) systems. The IC50 values for MDA-MB-231 and MCF-7 monolayer culture was calculated as 1.86 ± 0.17 µM and 2.22 ± 0.08 µM, respectively, and in (3D) spheroids of MDA-MB-231 cells, the IC50 value was calculated to be 1.51 ± 0.29 µM. It was observed that the complex outperformed cisplatin in both breast cancer cell lines. The cells treated with complex 1 underwent severe DNA damage, increased oxidative stress and cell cycle arrest which finally led to programmed cell death or apoptosis in triple negative breast cancer cells through an intrinsic pathway. [ABSTRACT FROM AUTHOR]

Patients with early-stage triple-negative breast cancer (TNBC) with residual invasive disease after neoadjuvant therapy have a high risk of recurrence even with neoadjuvant and adjuvant treatment with pembrolizumab. Sacituzumab govitecan, a Trop-2-directed antibody–drug conjugate with a topoisomerase I inhibitor payload, improved progression-free survival (PFS) and overall survival (OS) versus chemotherapy in patients with pre-treated metastatic TNBC. Moreover, preclinical data suggest that topoisomerase I inhibitors may enhance the effects of immune checkpoint inhibitors through activation of the cGAS-STING pathway. Here we describe the international randomized phase III AFT-65/ASCENT-05/OptimICE-RD trial, which evaluates the efficacy and safety of sacituzumab govitecan plus pembrolizumab versus treatment of physician's choice (pembrolizumab ± capecitabine) among patients with early-stage TNBC with residual invasive disease after neoadjuvant therapy. Clinical Trial Registration:NCT05633654 (ClinicalTrials.gov) Other Study ID Number(s): Gilead Study ID: GS-US-595-6184 Registration date: 1 December 2022 Study start date: 12 December 2022 Recruitment status: Recruiting Plain Language Summary AFT-65/ASCENT-05/OptimICE-RD is an ongoing clinical trial that is testing a new treatment combination for patients with stage II or III triple-negative breast cancer (TNBC). Stage II–III means the cancer is confined to the breast and/or nearby lymph nodes and can be surgically removed. However, there remains a risk that the cancer could recur after surgery. To reduce this risk, patients with stage II–III TNBC receive anti-cancer medication before and after surgery. For some patients, receipt of anti-cancer medication before surgery produces a pathologic complete response (pCR), meaning there is no observable cancer left behind at surgery. Patients with a pCR have a lower risk of recurrence than patients with residual disease. The AFT-65/ASCENT-05/OptimICE-RD trial includes people with stage II-III TNBC who have residual cancer after completing their course of pre-surgery anti-cancer medication. All participants have any remaining cancer in their breast and/or lymph nodes removed surgically, after which they are randomly assigned to receive one of two treatments. The experimental therapy consists of pembrolizumab along with a medication called sacituzumab govitecan, which kills cancer cells directly and may strengthen the anti-cancer immune response. Pembrolizumab strengthens the anti-cancer immune response, so the hypothesis of this trial is that the two medications will be more effective together. The control therapy consists of pembrolizumab, alone or in combination with a chemotherapy medication called capecitabine, which is the current standard of care. To study the effectiveness of each treatment, the researchers are following up with all participants to learn if and when their breast cancer returns. Article highlights Background Patients with stage II-III triple-negative breast cancer (TNBC) with residual invasive disease after neoadjuvant therapy have a high risk of recurrence with current standard-of-care adjuvant therapy regimens. Trop-2 is a transmembrane protein that is highly expressed on epithelial cancers, including TNBC. Sacituzumab govitecan is an antibody–drug conjugate consisting of an anti-Trop-2 antibody conjugated to SN-38 (the active metabolite of the DNA topoisomerase I inhibitor irinotecan) via a hydrolizable linker. This formulation facilitates release of SN-38 intracellularly as well as outside of cancer cells in the tumor microenvironment, creating a bystander killing effect. Preclinical evidence suggests that sacituzumab govitecan and anti-PD-1/PD-L1 agents exert synergistic activity. DNA-damaging agents activate cGAS-STING signaling, which results in recruitment of anti-tumor immune cells through type I interferon signaling. Immune cell activity is enhanced by the immune checkpoint inhibitor. AFT-65/ASCENT-05/OptimICE-RD Trial The randomized, open-label, phase III AFT-65/ASCENT-05/OptimICE-RD trial investigates the combination of sacituzumab govitecan plus pembrolizumab versus treatment of physician's choice (TPC; pembrolizumab alone or in combination with capecitabine) in patients with stage II-III TNBC with residual invasive disease in the breast or lymph nodes after completion of neoadjuvant therapy. Patients must be at least 18 years old with histologically confirmed TNBC, clinical stage T1, N1-2 or T2-4, N0-2. Patients must have received at least 6 cycles of neoadjuvant anthracycline and/or taxane-containing chemotherapy with or without an immune checkpoint inhibitor. Approximately 1514 patients will be randomized 1:1 to receive sacituzumab govitecan 10 mg/kg IV on day 1 and day 8, every 21 days for 8 cycles, plus pembrolizumab 200 mg IV on day 1 every 21 days for 8 cycles, or TPC, which consists of pembrolizumab 200 mg IV on day 1 every 21 days for 8 cycles with or without capecitabine 1000 mg/m2 orally twice daily on day 1–14 every 21 days for 8 cycles. The primary end point is iDFS. Secondary end points include overall survival, recurrence-free survival and safety and tolerability. Exploratory end points include analysis of Trop-2 and PD-L1 expression on tumor tissue and correlation with clinical outcomes. Patient-reported outcomes (PROs) include the FACT-B, EQ-5D-5L and PRO-CTCAE. Conclusion Results from the randomized phase III AFT-65/ASCENT-05/OptimICE-RD trial will provide efficacy and safety data for sacituzumab govitecan plus pembrolizumab versus pembrolizumab (alone or in combination with capecitabine) that could lead to a novel, more effective therapeutic combination to prevent disease recurrence in patients with stage II-III TNBC with residual invasive disease after the completion of neoadjuvant therapy. [ABSTRACT FROM AUTHOR]

Background: Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking hormone receptors and HER2 expression, leading to limited treatment options and poor prognosis. Mitophagy, a selective autophagy process targeting damaged mitochondria, plays a complex role in cancer progression, yet its prognostic significance in TNBC is not well understood. Methods: This study utilized single-cell RNA sequencing data from the TCGA and GEO databases to identify mitophagy-related genes (MRGs) associated with TNBC. A prognostic model was developed using univariate Cox analysis and LASSO regression. The model was validated across multiple independent cohorts, and correlations between MRG expression, immune infiltration, and drug sensitivity were explored. Results: Nine key MRGs were identified and used to stratify TNBC patients into high-risk and low-risk groups, with the high-risk group showing significantly worse survival outcomes. The model demonstrated strong predictive accuracy across various datasets. Additionally, the study revealed a correlation between higher MRG expression levels and increased immune cell infiltration, as well as potential responsiveness to specific chemotherapeutic agents. Conclusion: The mitophagy-related prognostic model offers a novel method for predicting outcomes in TNBC patients and highlights the role of mitophagy in influencing the tumor microenvironment, with potential applications in personalized treatment strategies. [ABSTRACT FROM AUTHOR]

The gut microbiota influences multiple aspects of human health and disease. Several studies have indicated an association between the gut microbiota and response to immune checkpoint inhibitors in various cancers, but there is scarce data from breast cancer. The randomized ALICE trial demonstrated improved progression‐free survival (PFS) from adding the programmed cell death 1 ligand 1 (PD‐L1) inhibitor atezolizumab (atezo) to immunomodulating chemotherapy (chemo) in metastatic triple‐negative breast cancer (mTNBC), even for PD‐L1negative disease. Herein, we investigated the microbiota composition and dynamics in the ALICE patients and their association with clinical outcome, by analyzing fecal samples collected at baseline and after 8 weeks. We applied 16S (V3‐V4) rRNA sequencing to characterize the diversity and taxonomic composition. Kaplan–Meier and Cox proportional hazard models were used for time‐to‐event analyses. We found that high alpha diversity by Faith's phylogenetic diversity (PD) at baseline was associated with prolonged PFS in the total study population and in the atezo‐chemo arm, but not in the placebo‐chemo arm. Moreover, Faith's PD appeared to be predictive of benefit from atezolizumab. Patients with high Faith's PD exhibited a PFS hazard ratio of 0.34 (P = 0.018) in favor of the atezo‐chemo arm, compared to 0.83 (P = 0.62) in the low Faith's PD group. Faith's PD was significantly reduced during treatment. At baseline, Bifidobacterium was significantly overrepresented in patients without clinical benefit in the atezo‐chemo arm, but not in the placebo‐chemo arm. These findings suggest that alpha diversity by Faith's PD should be further investigated as a prognostic and predictive biomarker in patients with mTNBC receiving chemo‐immunotherapy. [ABSTRACT FROM AUTHOR]

Despite a rise in clinical use of radiopharmaceutical therapies, the biological effects of radionuclides and their relationship with absorbed radiation dose are poorly understood. Here, we set out to define this relationship for Auger electron emitters [99mTc]TcO 4 − and [123I]I− and β−-particle emitter [188Re]ReO 4 −. Studies were carried out using genetically modified cells that permitted direct radionuclide comparisons. Triple-negative MDA-MB-231 breast cancer cells expressing the human sodium iodide symporter (hNIS) and green fluorescent protein (GFP; MDA-MB-231.hNIS-GFP) were used. In vitro radiotoxicity of [99mTc]TcO 4 −, [123I]I−, and [188Re]ReO 4 − was determined using clonogenic assays. Radionuclide uptake, efflux, and subcellular location were used to calculate nuclear absorbed doses using the Medical Internal Radiation Dose (MIRD) formalism. In vivo studies were performed using female NSG mice bearing orthotopic MDA-MB-231.hNIS-GFP tumors and compared with X-ray–treated (12.6-15 Gy) and untreated cohorts. Absorbed dose per unit activity in tumors and sodium iodide symporter–expressing organs was extrapolated to reference human adult models using OLINDA/EXM. [99mTc]TcO 4 − and [123I]I− reduced the survival fraction only in hNIS-expressing cells, whereas [188Re]ReO 4 − reduced survival fraction in hNIS-expressing and parental cells. [123I]I− required 2.4- and 1.5-fold lower decays/cell to achieve 37% survival compared with [99mTc]TcO 4 − and [188Re]ReO 4 −, respectively, after 72 hours of incubation. Additionally, [99mTc]TcO 4 −, [123I]I−, and [188Re]ReO 4 − had superior cell killing effectiveness in vitro compared with X-rays. In vivo, X-ray led to a greater median survival compared with [188Re]ReO 4 − and [123I]I− (54 days vs 45 and 43 days, respectively). Unlike the X-ray cohort, no metastases were visualized in the radionuclide-treated cohorts. Extrapolated human absorbed doses of [188Re]ReO 4 − to a 1 g tumor were 13.8- and 11.2-fold greater than for [123I]I− in female and male models, respectively. This work reports reference dose-effect data using cell and tumor models for [99mTc]TcO 4 −, [123I]I−, and [188Re]ReO 4 − for the first time. We further demonstrate the tumor-controlling effects of [123I]I− and [188Re]ReO 4 − in comparison with external beam radiation therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] Targeted breast cancer therapies hold the potential to improve the efficiency of drug delivery to the pathology site without impacting the viability and function of healthy cells. Herein, we developed multifunctional nanocarriers that target simultaneously several downstream signaling processes in triple negative breast cancer cells. The system comprises pH sensitive CaCO 3 nanoparticles (NPs) as carriers of the anticancer drug doxorubicin (DOX). The NPs were coated in a layer-by-layer (LbL) fashion using poly- l -lysine and hyaluronic acid to target receptors overexpressed in breast cancer (e.g. CD44, RHAMM). Spheroids of the triple-negative Hs578T cell line were used as a 3D model to assess the therapeutic potential of this system. Our results showed that the NPs act via a synergistic mechanism that combines Ca2+ overload causing cell calcification and DNA damage by DOX. The LbL coating was crucial for the protection of the healthy cells, i.e. it provides NPs with targeting capacity. The overall data suggests that the LbL-coated NPs loaded with DOX hold great potential for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

Symphorema polyandrum belongs to the Lamiaceae family and is locally known as Badichang or mahasindhu. In this study, we performed Soxhlet extraction to prepare methanolic and hydromethanolic extracts, followed by quantification of their total phenolic content and total flavonoid content. Qualitative analysis of both the extracts was conducted to determine the presence of different phytochemicals. In addition, we aimed to identify the important phytochemical constituents in the methanolic extracts of S. polyandrum (SPM) using ultra-performance liquid chromatography hyphenated with high-resolution mass spectrometry (UPLC–ESI–QTOF–MSE). Furthermore, this study investigated the antioxidant, anticancer and anti-inflammatory properties of SPM and its safety profile in the normal fibroblast cell line L929. A colony proliferation assay and a Griess assay were performed to evaluate the effects of SPM on colony formation and nitric oxide (NO) production. A total of 13 important phytochemicals were identified and reported. The methanolic extract of SPM demonstrated significant antioxidant activity. SPM also showed substantial antiproliferative activity on MDA-MB-231 triple-negative breast cancer cells, with an IC50 value of 45.53 ± 1.63 µg/ml, and also reduced the survival of these cancer cells by promoting nuclear fragmentation and condensation without causing harm to normal cells. SPM inhibits the colony formation and reduces the nitric oxide (NO) production. The anti-inflammatory potential of SPM was assessed utilizing the murine alveolar macrophages (J774.A.1) as an in vitro model, and SPM effectively lowered the levels of proinflammatory cytokines such as TNF-α and IL-6. These findings emphasized the antiproliferative potential of SPM to cancer cells, along with its anti-inflammatory, and antioxidant capabilities, indicating the therapeutic efficacy of this medicinal plant. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) continues to pose a significant obstacle in the field of oncology. Dysregulation of lipid metabolism, notably upregulated ketogenesis, has emerged as a hallmark of TNBC, yet its role in metastasis has been elusive. Here, by utilizing clinical specimens and experimental models, the study demonstrates that increased ketogenesis fosters TNBC metastasis by promoting the up-regulation of β-hydroxybutyrate (β-OHB), a key ketone body. Mechanistically, β-OHB facilitates β-hydroxybutyrylation (Kbhb) of Calpastatin (CAST), an endogenous calpain (CAPN) inhibitor, at K43, blocking the interaction with CAPN and subsequently promoting FAK phosphorylation and epithelial‒mesenchymal transition (EMT). In conclusion, the study reveals a novel regulatory axis linking ketogenesis to TNBC metastasis, shedding light on the intricate interplay between metabolic reprogramming and tumor progression. [ABSTRACT FROM AUTHOR]

Triple negative breast cancer (TNBC) is the most aggressive subtype in breast tumors. When re‐analyzing TCGA breast cancer dataset, we found cell adhesion molecules are highly enriched in differentially expressed genes in TNBC samples, among which Focal Adhesion Kinase (FAK) is most significantly associated with poor survival of TNBC patients. FAK is precisely modulated in the focal adhesion dynamics. To investigate whether lncRNAs regulate FAK signaling, we performed RNA immunoprecipitation sequencing and found FAISL (FAK Interacting and Stabilizing LncRNA) abundantly enriched in FAK‐interacting lncRNAs and frequently overexpressed in TCGA TNBC tissues. FAISL promotes TNBC cell adhesion, cytoskeleton spreading, proliferation, and anchor‐independent survival. FAISL doesn't affect FAK mRNA but positively regulates FAK protein level by blocking Calpain 2‐mediated proteolysis. FAISL interacts with the C‐terminus domain of FAK, whereby masks the binding site of Calpain 2 and prevents FAK cleavage. High level of FAISL correlates with FAK expression in tumor tissues and poor prognosis of TNBC patients. A siRNA delivery system targeting FAISL using reduction‐responsive nanoparticles effectively inhibits tumor growth and metastasis in TNBC mouse models. Together, these findings uncover a lncRNA‐mediated mechanism of regulating FAK proteolysis in the TNBC progression, and highlight the potential of targeting lncRNA FAISL for TNBC treatment. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is known for its aggressive nature, lack of effective diagnostic tools and treatments, and generally poor prognosis. The objective of this study was to investigate metabolic changes in TNBC using metabolomics approaches and explore the underlying mechanisms through integrated analysis with transcriptomics. In this study, serum untargeted metabolic profiles were first examined between 18 TNBC patients and 21 healthy control (HC) subjects using liquid chromatography-mass spectrometry (LC-MS), identifying a total of 22 significantly differential metabolites (DMs). Subsequently, receiver operating characteristic analysis revealed that 7-methylguanine could serve as a potential biomarker for TNBC in both the discovery and validation sets. Additionally, transcriptomic datasets were retrieved from the GEO database to identify differentially expressed genes (DEGs) between TNBC and normal tissues. An integrative analysis of the DMs and DEGs was conducted, uncovering potential molecular mechanisms underlying TNBC. Notably, three pathways—tyrosine metabolism, phenylalanine metabolism, and glycolysis/gluconeogenesis—were enriched, providing insight into the energy metabolism disorders in TNBC. Within these pathways, two DMs (4-hydroxyphenylacetaldehyde and oxaloacetic acid) and six DEGs (MAOA, ADH1B, ADH1C, AOC3, TAT, and PCK1) were identified as key components. In summary, this study highlights metabolic biomarkers that could potentially be used for the diagnosis and screening of TNBC. The comprehensive analysis of metabolomics and transcriptomics data offers a validated and in-depth understanding of TNBC metabolism. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common cancer diagnosed in women worldwide. However, the effective treatment for breast cancer progression is still being sought. The activation of cannabinoid receptor (CB) has been shown to negatively affect breast cancer cell survival. Our previous study also reported that breast cancer cells responded to various combinations of CB1 and CB2 agonists differently. Nonetheless, the mechanism underlying this effect and whether this phenomenon can be seen in other cancer characteristics remain unknown. Therefore, this study aims to further elucidate the effects of highly selective CB agonists and their combination on triple-negative breast cancer proliferation, cell cycle progression, invasion, lamellipodia formation as well as proteomic profile of MDA-MB-231 breast cancer cells. The presence of CB agonists, specifically a 2:1 (ACEA: GW405833) combination, prominently inhibited colony formation and induced the S-phase cell cycle arrest in MDA-MB-231 cells. Furthermore, cell invasion ability and lamellipodia formation of MDA-MB-231 were also attenuated by the exposure of CB agonists and their 2:1 combination ratio. Our proteomic analysis revealed proteomic profile alteration in MDA-MB-231 upon CB exposure that potentially led to breast cancer suppression, such as ZPR1/SHC1/MAPK-mediated cell proliferation and AXL/VAV2/RAC1-mediated cell motility pathways. Our findings showed that selective CB agonists and their combination suppressed breast cancer characteristics in MDA-MB-231 cells. The exposure of CB agonists also altered the proteomic profile of MDA-MB-231, which could lead to cell proliferation and motility suppression. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is considered the most aggressive form of breast cancer owing to the negative expression of targetable bioreceptors. Epithelial to mesenchymal transition (EMT) associated with metastatic abilities is its critical feature. As an attempt to target TNBC, nanotechnology was utilised to augment the effects of drug repurposing. Concerning that, a combination therapeutic module was structured with one of the aspects being a repurposed antihistamine, promethazine hydrochloride loaded PLGA nanoparticles. The as-synthesized nanoparticles were 217 nm in size and fluoresced at 522 nm, rendering them suitable for theranostic applications too. The second feature of the module was a common histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), used as a form of pre-treatment. Experimental studies demonstrated efficient cellular internalisation and significant innate anti-proliferative potential. The use of SAHA sensitised the cells to the drug loaded nanoparticle treatment. Mechanistic studies showed increase in ROS generation, mitochondrial dysfunction followed by apoptosis. Investigations into protein expression also revealed reduction of mesenchymal proteins like vimentin by 1.90 fold; while increase in epithelial marker like E-Cadherin by 1.42 fold, thus indicating an altered EMT dynamics. Further findings also provided better insight into the benefits of SAHA potentiated targeting of tumor spheroids that mimic solid tumors of TNBC. Thus, this study paves the avenue to a more rational translational validation of combining nanotherapeutics with drug repurposing. [ABSTRACT FROM AUTHOR]

Immunotherapy stands as the frontrunner in treatment strategies imparting efficient remission in various types of cancer. In fact, emerging breakthroughs with immune checkpoint inhibitors (ICI) in a spectrum of cancers have evoked interest in research related to the potential effects of immunotherapy in breast cancer patients. A major challenge with breast cancer is the molecular heterogeneity that limits the efficacy of many therapeutic regimes. Clinical trials have shown favorable clinical outcomes with immunotherapeutic options in some subtypes of breast cancer. However, ICI monotherapy may not be sufficient for all breast cancer patients, emphasizing the need for combinatorial approaches. Ongoing research is focused on untangling the interplay of ICI with established as well as novel anticancer therapeutic regimens in preclinical models of breast cancer. Our review will analyze the existing research regarding the mechanisms and clinical impact of immunotherapy for the treatment of breast cancer. We shall evaluate the role of immune cell modulation for improved therapeutic response in breast cancer patients. This review will provide collated evidences about the current clinical trials that are testing out the implications of immunotherapy in conjunction with traditional treatment modalities in breast cancer and summarize the potential future research directions in the field. In addition, we shall underline the recent findings related to microbiota modulation as a key regulator of immune therapy response in cancer patients and its plausible applications in breast cancer. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess homologous recombination deficiency (HRD) status and its correlation with carboplatin treatment response in early triple-negative breast cancer (TNBC) patients. Methods: Tumor tissues from 225 consecutive TNBC patients were evaluated with an HRD panel and homologous recombination-related (HRR) gene expression data. HRD positivity was defined as a high HRD score and/or BRCA1/2 pathogenic or likely pathogenic mutation. Clinicopathological factors, neoadjuvant treatment response, and prognosis were analyzed with respect to HRD status in these TNBC patients. Results: HRD positivity was found in 53.3% of patients and was significantly related to high Ki67 levels (P = 0.001). In patients who received neoadjuvant chemotherapy, HRD positivity (P = 0.005) or a high HRD score (P = 0.003) was significantly associated with a greater pathological complete response (pCR) rate, especially in those treated with carboplatin-containing neoadjuvant regimens (HRD positivity vs. negativity: 50.00% vs. 17.65%, P = 0.040). HRD positivity was associated with favorable distant metastasis-free survival (hazard ratio HR 0.49, 95% confidence interval CI 0.26–0.90, P = 0.022) and overall survival (HR 0.45, 95% CI 0.20–0.99, P = 0.049), irrespective of carboplatin treatment. Conclusion: TNBC patients with high HRDs had high Ki67 levels and BRCA mutations. HRD-positive TNBC patients treated with carboplatin had a higher pCR rate. Patients with HRD positivity had a better prognosis, irrespective of carboplatin treatment, warranting further evaluation. [ABSTRACT FROM AUTHOR]

Nuclear metabolism and DNA damage response are intertwined processes, but the precise molecular links remain elusive. Here, we explore this crosstalk using triple-negative breast cancer (TNBC) as a model, a subtype often prone to DNA damage accumulation. We show that the de novo purine synthesis enzyme IMPDH2 is enriched on chromatin in TNBC compared to other subtypes. IMPDH2 chromatin localization is DNA damage dependent, and IMPDH2 repression leads to DNA damage accumulation. On chromatin, IMPDH2 interacts with and modulates PARP1 activity by controlling the nuclear availability of NAD+ to fine-tune the DNA damage response. However, when IMPDH2 is restricted to the nucleus, it depletes nuclear NAD+, leading to PARP1 cleavage and cell death. Our study identifies a non-canonical nuclear role for IMPDH2, acting as a convergence point of nuclear metabolism and DNA damage response. Metabolism plays an important role in response to DNA damage, however the underlying mechanisms are less clear. Here, the authors identify a non-canonical role of IMPDH2 wherein it is recruited to the chromatin following DNA damage and mediates PARP1-dependent DNA damage repair via the regulation of nuclear NAD+ levels. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer with an unmet clinical need, but its epigenetic regulation remains largely undefined. By performing multiomic profiling, we recently revealed distinct super-enhancer (SE) patterns in different subtypes of breast cancer and identified a number of TNBC-specific SEs that drive oncogene expression. One of these SEs, TCOF1 SE, was discovered to play an important oncogenic role in TNBC. However, the molecular mechanisms by which TCOF1 SE promotes the expression of the TCOF1 gene remain to be elucidated. Here, by using combinatorial approaches of DNA pull-down assay, bioinformatics analysis and functional studies, we identified FOSL1 as a key transcription factor that binds to TCOF1 SE and drives its overexpression. shRNA-mediated depletion of FOSL1 results in significant downregulation of TCOF1 mRNA and protein levels. Using a dual-luciferase reporter assay and ChIP-qPCR, we showed that binding of FOSL1 to TCOF1 SE promotes the transcription of TCOF1 in TNBC cells. Importantly, our data demonstrated that overexpression of FOSL1 drives the activation of TCOF1 SE. Lastly, depletion of FOSL1 inhibits tumor spheroid growth and stemness properties of TNBC cells. Taken together, these findings uncover the key epigenetic role of FOSL1 and highlight the potential of targeting the FOSL1-TCOF1 axis for TNBC treatment. [ABSTRACT FROM AUTHOR]

Triple‐negative breast cancer (TNBC) lacks expression of the oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2/neu), has an aggressive tumor phenotype, shows only a partial response to chemotherapy, and lacks clinically established targeted therapies. Therefore, there is a need to develop more effective drugs for the treatment of TNBC. The ferrocenyl benzoxazine and α‐aminocresols class of compounds gave a potential source of multimodal inhibitors of cancer based on previous studies. In this study, a set of ferrocenyl benzoxazines and α‐aminocresols were screened and characterized as potential inhibitors of TNBC in vitro. A panel of 11 compounds was screened for selective cytotoxicity to cancer cells over normal cell equivalents. Focusing on the previously proposed modes of action of their building blocks, α‐aminocresols 3a and 3b exhibited significant DNA binding capabilities and caused robust DNA damage in TNBC cells. In addition, both compounds exhibited significant ROS generation capability; however, introducing a ROS quencher in a cell viability assay only partially rescued the cells from the cytotoxicity effects of the α‐aminocresols. This, together with the observation that compounds 3a and 3b triggered significant protein aggregation in HCC1806 cells, supports a mixed mode of action for these compounds. [ABSTRACT FROM AUTHOR]

Prolyl-4-hydroxylase subunit alpha3 (P4HA3) is a triple helical procollagen synthesis protein. The role of P4HA3 in cancer development is not well known and lacks comprehensive analyses among human cancers. This study aimed to investigate the relationship between P4HA3 expression and anti-tumor immunity and its prognostic value in pan-cancer. P4HA3 expression was analyzed from TIMER2.0, GTEx, GEPIA2.0 and TCGA databases. Genetic and DNA methylation alterations, survival analysis and proteins co-expression analysis of P4HA3 in cBio Cancer Genomics Portal, TCGA, GSCA and TIMER2.0. The correlation between P4HA3 expression and immune infiltration was analyzed by TIDE, XCELL, MCPCOUNTER, and EPIC. We performed EdU and transwell experiments to evaluate the influence of P4HA3 on the proliferation, migration and invasion abilities of different tumors. Patients derived xenograft (PDX) and subcutaneous transplantation models were utilized to explore the correlation between P4HA3 and immunotherapy response in triple-negative breast cancer (TNBC). Among 33 types of cancers, P4HA3 had generally different expression between different tumors, further analysis showed that the expression of P4HA3 was correlated with the cells infiltration of the tumor microenvironment (TME). The expression of P4HA3 was positively with the cell proliferation markers and epithelial-mesenchymal transition (EMT) markers. Moreover, P4HA3 deficiency inhibited the proliferation, migration and invasion abilities of tumor cells, and promoted anti-tumor immunotherapy of PD-1/PD-L1 inhibitor. This pan-cancer analysis of P4HA3 provides a comprehensive understanding of its oncogenic and prognosis role in different cancers, P4HA3 abnormal expression could be a useful biomarker for predicting the effectiveness of immunotherapy in cancer patients. Author summary: The results in this study presented the close correlation and the significant prognostic value of P4HA3 aberrant expression among diverse human tumors. Because the expression of P4HA3 was up-regulated in various of tumors and correlated with worse survival prognosis, we thought that P4HA3 possibly become a new therapeutic target for cancers. More importantly, our research provided a significant perspective in the important role of P4HA3 in anti-tumor immunotherapy and CAFs infiltration. The aberrant expression of P4HA3 might modulate tumor metabolic activity, immune cells and EMT processes in cancers. Future prospective research focusing on P4HA3 and TME could be useful for providing an immuno-based and metabolic-based anti-tumor therapeutic strategies. [ABSTRACT FROM AUTHOR]

Transposable elements (TEs) are indispensable for human development, with critical functions in pluripotency and embryogenesis. TE sequences also contribute to human pathologies, especially cancer, with documented activities as cis / trans transcriptional regulators, as sources of non-coding RNAs, and as mutagens that disrupt tumor suppressors. Despite this knowledge, little is known regarding the involvement of TE-derived genes (TEGs) in tumor pathogenesis. Here, systematic analyses of TEG expression across human cancer reveal a prominent role for pogo TE derived with KRAB domain (POGK). We show that POGK acts as a tumor suppressor in triple-negative breast cancer (TNBC) cells and that it couples with the co-repressor TRIM28 to directly block the transcription of ribosomal genes RPS16 and RPS29, in turn causing widespread inhibition of ribosomal biogenesis. We report that POGK undergoes deactivation by isoform switching in clinical TNBC, altogether revealing its exapted activities in tumor growth control. [Display omitted] • Widespread, substantial deregulation of TE-derived genes in human cancer • POGK exerts tumor-suppressive functions in TNBC • POGK suppresses global ribosomal biogenesis by inhibiting RPS16 and RPS29 • Inactivation of POGK growth-suppressive functions in TNBC by exon skipping Transposable element sequences occupy >50% of the human genome and serve evolutionarily critical roles in development. Here, Tu et al. show that the transposable-element-derived gene POGK partners with TRIM28 to inhibit transcription of ribosomal genes RPS16 and RPS29, thereby disrupting ribosomal biogenesis and aiding in triple-negative breast cancer growth control. [ABSTRACT FROM AUTHOR]

Background: Sacituzumab govitecan is an antibody-drug conjugate that is FDA approved for refractory metastatic triple-negative breast cancer. It targets the human trophoblastic cell-surface antigen 2 (Trop-2) with SN-38, a topoisomerase I inhibitor, attached to the antibody [1]. SN-38 breaks DNA strands and induces tumor apoptosis [2]. Acute kidney injury (AKI) is one of its adverse effects mainly prerenal due to gastrointestinal toxicity, but it has not been reported to cause acute tubulointerstitial nephritis (ATIN). Case Presentation: This report describes a rare adverse effect of sacituzumab govitecan, the approach to diagnosing the etiology of the patient's AKI, and the mechanism by which sacituzumab govitecan causes ATIN. A woman with metastatic ER positive, PR positive, HER2 negative breast cancer who was initiated on sacituzumab govitecan presents with vomiting and diarrhea, and findings of nephrotic-range proteinuria, negative anti-PLA2R antibody, and severe AKI requiring hemodialysis. She underwent kidney biopsy and pathology showed ATIN characterized by patchy interstitial inflammation alongside tubular injury without glomerular and vascular involvement. With intermittent renal replacement therapy, furosemide challenge, and a course of prednisone, the patient's kidney function recovered. Conclusions: Sacituzumab has a high affinity for Trop-2 protein which is also expressed within the collecting ducts, and to a lesser extent, the proximal tubule. Individuals, such as this patient, who express a homozygous genotype for UGT1A1*28 allele are at increased risk for AKI from sacituzumab govitecan due to decreased glucuronidation of SN-38. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is one of the most aggressive subtypes of breast cancer with higher rates of recurrence and distant metastasis, as well as decreased 5-year survival rates. Racial disparities are evident in the incidence and mortality rates of triple negative breast cancer particularly increased in young African American women. Concurrently, young African American women have multiple risk factors for TNBC including higher rates of premenopausal abdominal obesity (higher waist-hip ratio) and lower rates of breastfeeding with higher parity, implicating these factors as potentially contributors to poor outcomes. By understanding the mechanisms of how premenopausal obesity and lack of breastfeeding may be associated with increased risk of triple negative breast cancer, we can determine the best strategies for intervention and awareness to improve outcomes in TNBC. [ABSTRACT FROM AUTHOR]

Background: Cancer metastasis remains a major challenge in the clinical management of triple-negative breast cancer (TNBC). The NF-κB signaling pathway has been implicated as a crucial factor in the development of metastases, but the underlying molecular mechanisms remain largely unclear. Methods: PTPN20 expression was evaluated using data from the Sweden Cancerome Analysis Network-Breast and The Cancer Genome Atlas database, as well as by western blotting and immunohistochemistry in 88 TNBC patients. The ability of PTPN20 to activate NF-κB was assessed by luciferase reporter assays. The effects of PTPN20 overexpression and knockdown via short hairpin RNA were examined in TNBC cell lines by wound healing and transwell matrix penetration assays. Additionally, we analyzed the growth and metastasis abilitiy of 4T1 xenograft tumors in nude mice. Results: PTPN20 levels were elevated in TNBC cell lines and patient samples compared to controls, and higher protein levels correlated with metastasis-free survival. Overexpression of PTPN20 enhanced migration and invasion in vitro, and promoted lung metastasis in vivo. Our finding revealed that PTPN20 activates NF-κB signaling by dephosphorylating p65 at Ser468, preventing its binding to COMMD1, thereby protecting p65 from degradation. Downregulation of PTPN20 effectively inhibit, while p65 S468A mutant restored the migratory and invasive abilities of TNBC cells. Conclusions: Collectively, our results demonstrate that PTPN20 plays a critical role in TNBC metastasis through the activation of NF-κB signaling. We propose that PTPN20 may serve as a novel prognostic marker and potential therapeutic target for the treatment of TNBC. Highlights: The expression of PTPN20 was upregulated specially in triple-negative breast cancer. PTPN20 induces metastasis by promoting cell migration and invasion. PTPN20 dephosphorylates p65 and activates NF-κB signaling. PTPN20 may be a novel prognostic marker and a potential therapeutic target in the treatment of TNBC. [ABSTRACT FROM AUTHOR]

Background: Breast cancer, one of the most common forms of cancer, is associated with the highest cancer-related mortality among women worldwide. In comparison to other types of breast cancer, patients diagnosed with the triple-negative breast cancer (TNBC) subtype have the worst outcome because current therapies do not produce long-lasting responses. Hence, innovative therapies that produce persisting responses are a critical need. We previously discovered that hyperactivating purinergic receptors (P2RXs) by increasing extracellular adenosine triphosphate (eATP) concentrations enhances TNBC cell lines' response to chemotherapy. Heparan sulfate inhibits multiple extracellular ATPases, so it is a molecule of interest in this regard. In turn, heparanase degrades polysulfated polysaccharide heparan sulfate. Importantly, previous work suggests that breast cancer and other cancers express heparanase at high levels. Hence, as heparan sulfate can inhibit extracellular ATPases to facilitate eATP accumulation, it may intensify responses to chemotherapy. We postulated that heparanase inhibitors would exacerbate chemotherapy-induced decreases in TNBC cell viability by increasing heparan sulfate in the cellular microenvironment and hence, augmenting eATP. Methods: We treated TNBC cell lines MDA-MB 231, Hs 578t, and MDA-MB 468 and non-tumorigenic immortal mammary epithelial MCF-10A cells with paclitaxel (cytotoxic chemotherapeutic) with or without the heparanase inhibitor OGT 2115 and/or supplemental heparan sulfate. We evaluated cell viability and the release of eATP. Also, we compared the expression of heparanase protein in cell lines and tissues by immunoblot and immunohistochemistry, respectively. In addition, we examined breast-cancer-initiating cell populations using tumorsphere formation efficiency assays on treated cells. Results: We found that combining heparanase inhibitor OGT 2115 with chemotherapy decreased TNBC cell viability and tumorsphere formation through increases in eATP and activation of purinergic receptors as compared to TNBC cells treated with single-agent paclitaxel. Conclusion: Our data shows that by preventing heparan sulfate breakdown, heparanase inhibitors make TNBC cells more susceptible to chemotherapy by enhancing eATP concentrations. [ABSTRACT FROM AUTHOR]

Introduction: Triple-negative breast cancer (TNBC) is the most malignant type of breast cancer, and its prognosis is still the worst. It is necessary to constantly explore the pathogenesis and effective therapeutic targets of TNBC. Formononetin is an active ingredient with anti-tumor effects that we screened earlier. The main purpose of this study is to elucidate mechanism of the inhibitory effect of Formononetin on TNBC. Methods: We conducted experiments through both in vivo and in vitro methodologies. The in vivo experiments utilized a nude mice xenotransplantation model, while the in vitro investigations employed two breast cancer cell lines, MDA-MB-231 and MDA-MB-468. Concurrently, ferroptosis associated proteins, lipid peroxide levels, and proteins related to the rapamycin complex 1 were analyzed in both experimental settings. Results: In our study, Formononetin exhibits significant inhibitory effects on the proliferation of triple TNBC, both in vivo and in vitro. Moreover, it elicits an increase in lipid peroxide levels, downregulates the expression of ferroptosis-associated proteins GPX4 and xCT, and induces ferroptosis in breast cancer cells. Concurrently, Formononetin impedes the formation of the mammalian target of rapamycin complex 1 (mTORC1) and suppresses the expression of downstream Sterol regulatory element-binding protein 1(SREBP1). The utilization of breast cancer cells with SREBP1 overexpression or knockout demonstrates that Formononetin induces ferroptosis by modulating the mTORC1-SREBP1 signaling axis. Discussion: In conclusion, this study provides evidence that Formononetin exerts an anti-proliferative effect on triple-negative breast cancer by inducing ferroptosis. Moreover, the mTORC1-SREBP1 signal axis is identified as the primary mechanism through which formononetin exerts its therapeutic effects. These findings suggest that formononetin holds promise as a potential targeted drug for clinical treatment of TNBC. [ABSTRACT FROM AUTHOR]

Patients with metastatic triple-negative breast cancer (TNBC) show variable responses to PD-1 inhibition. Efficient patient selection by predictive biomarkers would be desirable but is hindered by the limited performance of existing biomarkers. Here, we leveraged in silico patient cohorts generated using a quantitative systems pharmacology model of metastatic TNBC, informed by transcriptomic and clinical data, to explore potential ways to improve patient selection. We evaluated and quantified the performance of 90 biomarker candidates, including various cellular and molecular species, at different cutoffs by a cutoff-based biomarker testing algorithm combined with machine learning-based feature selection. Combinations of pretreatment biomarkers improved the specificity compared to single biomarkers at the cost of reduced sensitivity. On the other hand, early on-treatment biomarkers, such as the relative change in tumor diameter from baseline measured at two weeks after treatment initiation, achieved remarkably higher sensitivity and specificity. Further, blood-based biomarkers had a comparable ability to tumor-or lymph node-based biomarkers in identifying a subset of responders, potentially suggesting a less invasive way for patient selection. [ABSTRACT FROM AUTHOR]

Receptor tyrosine kinase-like orphan receptor 1 (ROR1) is a tumour target currently used for the development of novel therapeutic modalities, such as antibody-drug conjugates, chimeric antigen receptor T-cell therapies, and others. Success of these new drugs depends on the selection of relevant indications based on ROR1 tumour prevalence, staining heterogeneity, and subcellular localization, among other parameters. We investigated ROR1 immunophenotype using validated antibody clones for immunohistochemistry (IHC) and flow cytometry (FC), analyzing 292 tumour specimens from 7 haematological malignancies and triple negative breast cancer (TNBC) as a reference solid tumour indication. ROR1 prevalence varied significantly across distinct tumour types, showing 100% of ROR1 positivity in all chronic lymphocytic leukaemia (n = 48) and hairy cell leukaemia (n = 14) specimens analyzed via FC with ranges between 1.1–99.8% and 0.8–62.1%, respectively. Samples analysed via IHC showed ROR1 membrane/cytoplasmic positivity in 44% of mantle cell lymphoma tumour samples (n = 27; H-score range: 10–285 in positive cases); 30% in TNBC (n = 46; H-score range: 1–200); 15% in diffuse large B-cell lymphoma (n = 45; H-score: 40–250); and 11% in follicular lymphoma (n = 34; H-score: 2–300). Finally, all acute myeloid leukaemia (n = 52) and most T-cell non-Hodgkin lymphoma (n = 31/32) tested samples were negative for ROR1 via IHC. In conclusion, ROR1 shows a heterogeneous tumour cell expression profile across multiple leukaemias and lymphomas, making it a tumour target that would require different patient selection strategies to develop novel therapeutic modalities. [ABSTRACT FROM AUTHOR]

Background: Menopausal hormone therapy (MHT) is associated with an increased risk of postmenopausal breast cancer, predominantly the luminal A-like subtype. The impact of MHT on deaths from breast cancer subtypes is less understood. This study aimed to explore associations between MHT use and the incidence, mortality, and survival of intrinsic-like breast cancer subtypes. Methods: Data from 160,881 participants with self-reported MHT use from the prospective Norwegian Women and Cancer Study were analyzed. Among them, 7,844 incident breast cancer cases, and 721 breast cancer-specific deaths occurred. Cox proportional hazard regression was performed to calculate hazard ratios (HRs) with 95% confidence intervals (CIs) for the association between MHT use and the incidence, mortality, and survival of breast cancer subtypes. Results: MHT use was associated with increased risk of overall, luminal A-like, and luminal B-like breast cancer, with respective HRs of 1.44 (95% CI 1.36–1.52), 1.41 (95% CI 1.31–1.52), and 1.23 (95% CI 1.09–1.40) among current estrogen-progestin therapy (EPT) users compared with never users. The risk increased by 4%, 4%, and 2% per year of EPT use for overall, luminal A-like, and luminal B-like breast cancers, respectively. MHT use was also associated with increased risk of overall and luminal A-like breast cancer mortality, with HRs 1.61% (95% CI 1.36–1.91) and 2.15% (95% CI 1.51–3.05) increased risk among current EPT users compared with non-users. Among patients with breast cancer, pre-diagnostic MHT use was not associated with worse survival from overall breast cancer but was inversely associated with survival from triple-negative breast cancer (TNBC; HR death 0.41; 95% CI 0.24–0.73 among current users). Results varied significantly according to tumor subtype (pheterogeneity = 0.02). Conclusions: Our study suggests that MHT use increases the risk of incident and fatal overall and luminal A-like, and incident luminal B-like breast cancer but does not decrease overall survival among patients with breast cancer. Further research is needed to elucidate the mechanisms underlying MHT use and breast cancer lethality, and to explore whether MHT use among patients with TNBC is indeed free from harm. [ABSTRACT FROM AUTHOR]

Introduction: Breast cancer is the most common cancer worldwide, the leading cause of cancer death in women, and the fifth leading cause of cancer death. Triple negative breast cancer (TNBC), with high metastasis and mortality rates, is the most challenging subtype in breast cancer treatment. There is an urgent need to develop anti-TNBC drugs with significant efficacy, low side effects and good availability. In early drug screening, blestriarene C was found to have inhibitory effects on TNBC cells. In this article, we further explore the mechanisms associated with blestriarene C for breast cancer. Methods: In this article, we take the approach of network pharmacology combined with in vivo and in vitro experiments. Network pharmacology analysis was used to predict the active components in Baiji, and to investigate the hub targets and related mechanisms of BC in TNBC treatment. The mechanism of anti-TNBC in vitro was evaluated by CCK-8 assay, cell apoptosis and cell cycle assays, wound healing assay, WB assay, and molecular docking analysis. The inhibition effect in vivo was test in subcutaneous tumor models established in mice. Results: Through network pharmacology analysis and experiments, we screened out BC as the main active ingredient, and found that BC could inhibit the Ras/ERK/c-Fos signaling pathway while downregulating the expression of HSP90AA1 and upregulating the expression of PTGS2, thereby promoting apoptosis, causing S-phase cycle arrest, and inhibiting the proliferation and migration of BT549 cells. The in vivo results illustrated that BC inhibited the growth of TNBC tumors and has a high safety profile. By integrating network pharmacology with in vitro and in vivo experiments, this study demonstrated that BC inhibited the proliferation and migration of TNBC cells by inhibiting the Ras/ERK/c-Fos signaling pathway, promoting apoptosis, and causing S-phase cycle arrest. Discussion: This study provides new evidence for the use of BC as a novel drug for TNBC treatment. [ABSTRACT FROM AUTHOR]

Nitric oxide (•NO) plays various pathophysiological roles in breast cancer, significantly influencing the migration of tumour cells through concentration gradients. Therefore, modulating •NO levels via selective scavenging presents a promising approach to treating aggressive •NO‐dependent cancers, such as triple‐negative breast cancer (TNBC). Hemin emerges as a potential scavenger of •NO; however, its metalloporphyrin molecules tend to aggregate in physiological solutions, which limits its biomedical applications. To address this, a modification strategy is employed to minimize aggregation and protect against physiological oxidative degradation while preserving •NO‐scavenging properties. This is achieved through a simple chemical transformation that involves hemin conjugation to aromatic residues, tyrosine, and tyramine via carbodiimide reactions. These derivatives exhibit altered electronic properties and oxidation potential compared to hemin, alongside reduced aggregation tendencies and retained •NO‐binding affinity in aqueous solutions. Furthermore, depending on the type of hemin derivative, there is an associated inhibition of TNBC cell migration. These model hemin compounds demonstrate varying •NO‐binding affinities and resistance levels to oxidative degradation and aggregation, offering insights into the design of •NO‐scavenging molecules with enhanced properties for cancer treatment. [ABSTRACT FROM AUTHOR]

Glucocorticoid receptor (GR) activation may promote metastasis in oestrogen receptor-negative and triple-negative breast cancer (TNBC). However, the role of the GRβ isoform, which has opposing effects to the main isoform, has not been studied in clinical samples. We aimed to analyse the intracellular localisation of total GR and GRβ in vitro using plasmid constructs and fluorescent immunocytochemistry. Additionally, our goal was to perform immunostaining for total GR and GRβ on two cohorts: (i) on 194 clinical breast cancer samples to compare the expression in different molecular subtypes, and (ii) on 161 TNBC samples to analyse the association of GR with survival. We supplemented our analysis with RNA data from 1097 TNBC cases. We found that in the absence of the ligand, GR resided in the cytoplasm of breast cancer cells, while upon ligand activation, it translocated to the nucleus. A negative correlation was found between cytoplasmic GRtotal and Ki67 in luminal A tumours, while the opposite trend was observed in TNBC samples. Tumours with strong lymphoid infiltration showed higher cytoplasmic GRtotal staining compared to those with weaker infiltration. Patients with high nuclear GRtotal staining had shorter progression-free survival in univariate analysis. High cytoplasmic GRβ was a marker for better overall survival in multivariate analysis (10-year overall survival HR [95% CI]: 0.46 [0.22–0.95], p = 0.036). As a conclusions, this study is the first to investigate GRβ expression in breast tumours. Different expression and cellular localisation of GRtotal and GRβ were observed in the context of molecular subtypes, underscoring the complex role of GR in breast cancer. An inverse association between cytoplasmic GRtotal and the Ki67 proliferation index was observed in luminal A and TNBC. Regarding the impact of GR on outcomes in TNBC patients, while cytoplasmic GRβ was associated with a better prognosis, patients with nuclear GRtotal staining may be at a higher risk of disease progression, as it negatively affects survival. Caution should be exercised when using glucocorticoids in patients with nuclear GR staining, as it may negatively impact survival. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) presents a significant challenge in oncology due to its aggressive nature and limited targeted therapeutic options. This study explores the potential of autocrine motility factor (AMF) and an AMF-derived peptide as novel treatments for TNBC. AMF, primarily secreted by neoplastic cells, plays a crucial role in cancer cell motility, metastasis, and proliferation. The research demonstrates that AMF and its derived peptide inhibit TNBC cell proliferation by modulating cellular migration, redox homeostasis, apoptotic pathways, and drug efflux mechanisms. Dose-dependent antiproliferative effects were observed across three TNBC cell lines, with higher concentrations impairing cellular migration. Mechanistic studies revealed decreased glucose-6-phosphate dehydrogenase expression and elevated reactive oxygen species production, suggesting redox imbalance as a primary mediator of apoptosis. Combination studies with conventional therapeutics showed near-complete eradication of resistant TNBC cells. The observed reduction in p53 levels and increased intranuclear doxorubicin accumulation highlight the AMF/AMF peptide's potential as multidrug resistance modulators. This study underscores the promise of using AMF/AMF peptide as a novel therapeutic approach for TNBC, addressing current treatment limitations and warranting further investigation. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) presents limited therapeutic options and is associated with poor prognosis. Early detection and the development of novel therapeutic agents are therefore imperative. Fibroblast activation protein (FAP) is a membrane protein expressed on cancer-associated fibroblasts (CAFs) that plays an essential role in TNBC proliferation, migration, and invasion. Consequently, it is hypothesized that the Astatine (211At)-labeled FAP inhibitor (FAPI) selectively exerts anti-tumor effects through alpha-particle emission. In this study, we aimed to assess its theranostic capabilities by integrating [18F]FAPI-74 PET imaging with targeted alpha therapy using [211At]FAPI1 in TNBC models. Mice xenografts were established by transplanting MDA-MB-231 and HT1080 cells (control). As a parallel diagnostic method, [18F]FAPI-74 was administered for PET imaging to validate FAP expression. A single dose of [211At]FAPI1 (1.04 ± 0.10 MBq) was administered to evaluate the therapeutic efficacy. [18F]FAPI-74 exhibited high accumulation in MDA-MB-231 xenografts, and FAP expression was pathologically confirmed via immunostaining. The group that received [211At]FAPI1 (n = 11) demonstrated a significantly enhanced anti-tumor effect compared with the control group (n = 7) (p = 0.002). In conclusion, [18F]FAPI-74 PET imaging was successfully used to diagnose FAP expression, and as [211At]FAPI1 showed promising therapeutic efficacy in TNBC models, it is expected to be a viable therapeutic option. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) represents an aggressive subtype characterized by high rates of recurrence and metastasis, necessitating the exploration of alternative treatment strategies. Oncolytic vaccinia virus (OVV) therapy has emerged as a promising approach, selectively infecting and destroying tumor cells. However, its efficacy is often hampered by inadequate viral distribution within the tumor microenvironment. Here, we investigate the potential of keratin (KTN) as a carrier for OVV delivery to enhance viral distribution and antitumor efficacy. In vitro assays revealed that KTN significantly improves OVV stability, leading to increased tumor cell apoptosis and necrosis. Furthermore, KTN effectively inhibits cancer cell migration by suppressing the epithelial–mesenchymal transition (EMT) process and downregulating metastasis-related proteins. These findings are corroborated in a syngeneic TNBC mouse model, where KTN-mediated OVV delivery enhances cytotoxic T cell-mediated antitumor immune responses without compromising the anti-angiogenic effects of the virus. Notably, KTN alone exhibits antitumor effects by suppressing tumor growth and metastasis, underscoring its potential as a standalone therapeutic agent. In conclusion, our study underscores the promise of KTN-mediated OVV delivery as a promising therapeutic strategy for TNBC. By improving viral distribution, suppressing EMT, and enhancing antitumor immunity, this approach holds significant potential for enhancing patient outcomes in TNBC treatment. Further investigation is warranted to explore the broader utility of KTN in various cancer therapy approaches. [ABSTRACT FROM AUTHOR]

Triple-negative breast cancer (TNBC) is associated with a generally poor prognosis due to its highly aggressive and metastatic nature, lack of targetable receptors, as well as the frequent development of resistance to chemotherapy. We previously reported that AU1, a small molecule developed as an inhibitor of BPTF (bromodomain PHD finger-containing transcription factor), was capable of sensitizing preclinical models of TNBC to chemotherapy in part via the promotion of autophagy. In studies reported here, we identify an additional property of this compound, specifically that sensitization is associated with the inhibition of the P-glycoprotein (P-gp) efflux pump. In silico molecular docking studies indicate that AU1 binds to active regions of the efflux pump in a manner consistent with the inhibition of the pump function. This work identifies a novel chemical structure that can influence multidrug efflux, an established mechanism of drug resistance in TNBC, that has not yet been successfully addressed by clinical efforts. [ABSTRACT FROM AUTHOR]

Simple Summary: Sacituzumab govitecan is a promising treatment option for patients with triple-negative breast cancer, a type of cancer that is difficult to treat due to the absence of hormone receptors, specifically human epidermal growth factor receptor 2. This study is designed to evaluate the efficacy and safety of sacituzumab govitecan, which targets the trophoblast cell surface antigen 2 found on tumor cells, compared to standard chemotherapy. Based on a systematic review of clinical trials, the results indicate that sacituzumab govitecan significantly improves clinical outcomes, providing greater therapeutic benefit with fewer side effects compared to conventional treatments. These findings may influence future treatment guidelines for this aggressive cancer and provide a new approach to its management. Background/Objectives: Triple-negative breast cancer is difficult to treat due to the absence of hormone receptors and Her2neu. Sacituzumab govitecan is a new therapeutic approach that uses an antibody directed against the Trop-2 antigen present in solid epithelial tumors, linked to the active metabolite SN-38, similar to irinotecan, to specifically target cancer cells while minimizing damage to healthy cells. The objective of the present review was to evaluate the efficacy and safety of sacituzumab govitecan as a single treatment in patients with triple-negative breast cancer and to compare its results with the standard conventional chemotherapy regimen currently used in this disease. Methods: A systematic review of randomized clinical trials of sacituzumab govitecan was performed. The search was performed in Medline (PubMed), Web of Science, and Cochrane from September 2022 to January 2024. Results: Thirty-eight articles are included and evaluated according to inclusion and exclusion criteria corresponding to the two most relevant clinical trials, including specific analyses of cohorts and subgroup study arms within these trials. Data from more recent clinical trials are also reviewed. Conclusions: The efficacy results showed a significantly greater clinical benefit with sacituzumab govitecan compared to standard chemotherapy in patients with triple-negative breast cancer. This drug will become a treatment of substantial impact in future treatment guidelines for this type of cancer. [ABSTRACT FROM AUTHOR]

Simple Summary: TRPS1 (trichorhinophalangeal syndrome type 1) is a protein that has become an important marker for diagnosing breast cancer, especially in difficult-to-diagnose cases like triple-negative breast cancer. This review explores the expression of TRPS1 in various cancers beyond breast tissue, such as prostate, lung, and ovarian cancers, and discusses its role as a diagnostic tool. While TRPS1 is a highly sensitive marker for breast cancer, its presence in other tumor types poses challenges for pathologists. Our review aims to raise awareness of these diagnostic pitfalls and emphasizes the importance of using multiple markers to improve accuracy. Understanding the broader expression of TRPS1 can help to improve cancer diagnosis and treatment strategies. Background/Objectives: Immunohistochemical expression of TRPS1 (trichorhinophalangeal syndrome type 1) protein is usually used by pathologists to confirm breast origin for triple-negative breast cancers (TNBC) or metastatic carcinomas of unknown primary. However, recent studies have reported TRPS1 expression in a variety of non-breast lesions. This review aims to provide a comprehensive evaluation of TRPS1 expression across various tumor types, highlighting both its diagnostic utility and potential pitfalls that may arise in clinical practice. Methods: A thorough search of the PubMed database on TRPS1 immunoexpression in tumor pathology was conducted. While the gene itself has been known for several decades, most studies regarding its use in immunohistochemistry emerged in the late 2010s. Particular emphasis was placed on case reports and cohort studies that examined the implications of TRPS1 expression in non-breast tissues, as well as variations in the results between commercially available TRPS1 clones, which may influence the staining intensity and specificity. Results: TRPS1 demonstrated a strong diagnostic utility in identifying primary breast lesions, particularly in TNBC cases. However, its expression in a growing number of non-breast cancers, such as lung adenocarcinoma, prostate adenocarcinoma, urothelial carcinoma, ovarian high-grade serous carcinoma, and endometrial adenocarcinoma, as well as up to 96% of synovial sarcomas with SS18-SSX fusion, emphasizes the need for caution when interpreting TRPS1 positivity and suggests a multi-marker approach in order to increase the diagnostic accuracy. Conclusions: While TRPS1 remains a highly sensible immunohistochemical marker for confirming breast primary lesions, pathologists should be aware of its low specificity and incorporate complementary diagnostic methods in order to ensure accurate clinical management. Further research should focus on elucidating the molecular pathways regulating TRPS1 expression in various tumor types, which may better define its clinical utility. [ABSTRACT FROM AUTHOR]

Anti-inflammatory nitro-fatty acids (NO 2 -FAs) are endogenous and pleiotropic mediators that exert tumor-suppressive effects via a novel mechanism of action by targeting a unique set of tumorigenic target proteins. NO 2 -FAs are promising tumor-selective antineoplastic agents with a favorable safety profile demonstrated in several preclinical models of disease and human clinical Phase 1 and 2 trials. In preclinical models of colorectal and triple-negative breast cancer, NO 2 -FA exhibited direct anticancer as well as chemo- and radiosensitizing effects in combination with DNA-damaging therapies by suppressing the 26S proteasome, RAD51, and NF-κB. Nitro-fatty acids (NO 2 -FAs) are endogenous pleiotropic lipid mediators regarded as promising drug candidates for treating inflammatory and fibrotic diseases. Over the past two decades, the anti-inflammatory and cytoprotective actions of NO 2 -FAs and several molecular targets have been identified. More recently, preclinical studies have demonstrated their potential as prospective cancer therapeutics with favorable safety and tumor-selective profiles. In this review, we describe the mechanisms of action, with a focus on NO 2 -FA antineoplastic and chemosensitizing effects. We also address the potential therapeutic applications of endogenous and structurally modified NO 2 -FAs species in cancer treatment. [ABSTRACT FROM AUTHOR]

Aberrant Notch, which is a defining feature of triple-negative breast cancer (TNBC) cells, regulates intercellular communication in the tumor immune microenvironment (TIME). This includes tumor-associated macrophage (TAM) recruitment through Notch-dependent cytokine secretion, contributing to an immunosuppressive TIME. Despite the low response rate of TNBC to immune checkpoint blockade (ICB), here, we report that inhibition of Notch-driven cytokine-mediated programs reduces TAMs and induces responsiveness to sequentially delivered ICB. This is characterized by the emergence of GrB+ cytotoxic T lymphocytes (CTLs) in the primary tumor. A more impressive effect of sequential treatment is observed in the lung where TAM depletion and increased CTLs are accompanied by near-complete abolition of metastases. This is due to (i) therapeutic reduction in Notch-dependent, prometastatic circulating factors released by the primary tumor, and (ii) elevated PD ligand 1 (PD-L1) in lung metastases, rendering them profoundly sensitive to ICB. These findings highlight the potential of combination cytokine inhibition and ICB as an immunotherapeutic strategy in TNBC. [ABSTRACT FROM AUTHOR]

• Anticancer activity of C. campestris on MDA-MB-231, RL-95-2, MCF-7, SH-SY5Y cells. • C. campestris extract has antioxidant activity through DPPH, ABTS, and FRAP tests. • Phenolic profile of the extract was determined HPLC-DAD analysis. • C. campestris extract has in vivo antitumoral effect on breast cancer model of mice. Globally, the mortality rate attributed to cancer is on a concerning upward trajectory. Cancer, characterized by aberrations in the normal cell cycle, excessive proliferation, and abnormal differentiation, poses a formidable health challenge. Notably, breast cancer, constituting over one-third of all cancers in women, stands out as a prevalent malignancy. While diverse treatment modalities are deployed in the battle against cancer, herbal remedies emerge as a compelling option for those seeking treatments with minimal side effects. Cuscuta campestris Yunck , a staple in traditional medicine renowned for its efficacy in addressing cancer and various ailments, assumes a pivotal role in herbal medicine. Our investigation delved into assessing the anticancer potential of ethanol extracts from Cuscuta campestris Yunck, employing MDA-MB-231 (triple negative breast cancer cells), RL-95-2 (endometrium cancer cells), MCF-7 (ER positive breast cancer cells), SH-SY5Y (Neuroblastoma cancer cells), COLO 205 (Colon cancer cells), and A-549 (lung cancer cells) cell lines. Additionally, the antioxidant activity of the ethanol extract was gauged through DPPH, ABTS, and FRAP tests. Phenolic compounds of the extract was determined HPL-DAD analysis. The research delved further into the practical implications of Cuscuta campestris Yunck extract by employing a solid Ehrlich Ascites Tumor (EAT) model in mice. Furthermore, our study extended to scrutinizing the ethanol extractʼs anticancer efficacy across distinct phases (proliferation phase: 0–14 days, plateau phase: 14–28 days) of the solid Ehrlich Ascites Tumor (EAC) model in mice. Isorhamnetin was found the highest flavonol amount as 16.97 ± 1.27 mg.g−1 in the Cuscuta campestris Yunck extract. DPPH SC 50 values of 0.021 ± 0.001 mg/mL, ABTS SC 50 values of as 0.653 ± 0.071 mg/mL and FRAP values of as 20.122 ± 0.708 (µmol trolox/g ext), respectively. Cuscuta campestris Yunck extract significantly decreased the cell viability beginning from the 1 mg/ml concentration at the MDA-MB-231 (triple negative breast cancer) and RL-95-2 (endometrial cancer) cell lines. The research delved further into the practical implications of Cuscuta campestris Yunck extract by employing a solid Ehrlich Ascites Tumor (EAT) model in mice. Here, the extract exhibited a significant reduction in tumor volumes compared to the control group, pointing towards its tangible efficacy in impeding tumor growth. This multifaceted study not only sheds light on the intricate phenolic composition and antioxidant capabilities of Cuscuta campestris Yunck but also underscores its promising role as a botanical source for potential cancer treatment. [ABSTRACT FROM AUTHOR]

The 4T1 model is extensively employed in murine studies to elucidate the mechanisms underlying the carcinogenesis of triple-negative breast cancer. Molecular biology serves as a cornerstone in these investigations. However, accurate gene expression analyses necessitate data normalization employing housekeeping genes (HKGs) to avert spurious results. Here, we initially delve into the characteristics of the tumor evolution induced by 4T1 in mice, underscoring the imperative for additional tools for tumor monitoring and assessment methods for tracking the animals, thereby facilitating prospective studies employing this methodology. Subsequently, leveraging various software platforms, we assessed ten distinct HKGs (GAPDH, 18 S, ACTB, HPRT1, B2M, GUSB, PGK1, CCSER2, SYMPK, ANKRD17) not hitherto evaluated in the 4T1 breast cancer model, across tumors and diverse tissues afflicted by metastasis. Our principal findings underscore GAPDH as the optimal HKG for gene expression analyses in tumors, while HPRT1 emerged as the most stable in the liver and CCSER2 in the lung. These genes demonstrated consistent expression and minimal variation among experimental groups. Furthermore, employing these HKGs for normalization, we assessed TNF-α and VEGF expression in tissues and discerned significant disparities among groups. We posit that this constitutes the inaugural delineation of an ideal HKG for experiments utilizing the 4T1 model, particularly in vivo settings. [ABSTRACT FROM AUTHOR]

Pembrolizumab-related thyroid dysfunction has been associated with better outcomes in metastatic cancer patients. This study aims to examine the outcomes (pathological complete response (pCR) and event-free survival (EFS)) in early-stage triple-negative breast cancer (TNBC) patients receiving preoperative therapy who developed pembrolizumab-related thyroid dysfunction. Patients were divided into four groups based on the occurrence or not of pembrolizumab-related thyroid dysfunction (group A and D, respectively) and, in case of pre-existing thyroid disorder, based on the need for levothyroxine start/adjustment or not (group B and C, respectively). pCR and EFS in groups A, B, and C were compared to the ones in group D. Sixty-four early-stage TNBC patients were included, and the median follow-up was 16.5 months (IQR 12.0-23.8). Multiple patterns of thyroid irAEs were observed (overt hypothyroidism in 56.3%, subclinical thyrotoxicosis in 28.1%, overt thyrotoxicosis and subclinical hypothyroidism in 21.9%, and 21.9% of patients). No statistical difference was found in pCR (chi-square test, P = 0.611) comparing groups A, B, and C to group D. The median EFS in groups A, B, and C and in group D were 16.5 (IQR 12.0-24.0) and 16.0 (IQR 12.0-22.3) months, respectively (log-rank test, P = 0.671). The percentage of patients obtaining pCR was 85.7% in patients developing pembrolizumab-related overt thyrotoxicosis and 42.1% in remaining patients (chi-square test, P = 0.036). The EFS was 16.0 months (IQR 12.0-25.0) in patients developing pembrolizumab--related overt thyrotoxicosis and 16.0 months (IQR 12.0-23.5) in the remaining patients (log-rank test, P = 0.494). In conclusion, multiple patterns of pembrolizumab-related thyroid dysfunction occur in early-stage TNBC. Patients developing pembrolizumab-related overt thyrotoxicosis are more likely to achieve pCR. [ABSTRACT FROM AUTHOR]

Background: Sacituzumab govitecan (SG) is a Trop-2–directed antibody–drug conjugate approved outside Japan for second-line and later metastatic triple-negative breast cancer (mTNBC), based on the ASCENT study (NCT02574455). We report SG safety and efficacy in an open-label, phase 1/2 bridging study in Japanese patients with advanced solid tumors (ASCENT-J02; NCT05101096; jRCT2031210346). Methods: Phase 1 was a standard 3 + 3 design. Patients received intravenous SG 6 mg/kg, escalating to 10 mg/kg, on Days 1 and 8 per 21-day cycle; primary endpoints were safety, incidence of dose-limiting toxicity/toxicities (DLTs), and determination of the recommended phase 2 dose (RP2D). In the multicohort phase 2 study, patients in the mTNBC cohort with previously treated disease received SG at the RP2D; primary endpoint was independent review committee (IRC)-assessed objective response rate (ORR; RECIST v1.1). Safety was a secondary endpoint. Results: In phase 1 (N = 15), one DLT (grade 3 elevated transaminases) occurred with SG 10 mg/kg; RP2D was SG 10 mg/kg regardless of UGT1A1 status. In phase 2, 36 patients with mTNBC received SG 10 mg/kg. At median follow-up of 6.1 months, IRC-assessed ORR was 25.0% (95% CI 12.1–42.2; P = 0.0077). Median progression-free survival was 5.6 months (95% CI 3.9–not reached [NR]); median overall survival was NR. No treatment-emergent adverse events led to discontinuation or death. Conclusions: SG RP2D was established as 10 mg/kg in Japanese patients. SG showed efficacy in Japanese patients with previously treated mTNBC, a manageable safety profile, and no new safety signals, consistent with the previous ASCENT study. [ABSTRACT FROM AUTHOR]

Ferroptosis primarily relies on reactive oxygen (ROS) production and lipid peroxide (LPO) accumulation, which opens up new opportunities for tumor therapy. However, a standalone ferroptosis process is insufficient in inhibiting tumor progression. Unlike previously reported Fe-based nanomaterials, we have engineered a novel nanoreactor named IR780/Ce@EGCG/APT, which uses metal-polyphenols network (Ce@EGCG) based on rare-earth cerium and epigallocatechin gallate (EGCG) to encapsulate IR780 and modified with the aptamer (AS1411). The intricately designed nanoreactor is specifically taken up by tumor cells, releasing Ce3+, EGCG, and IR780. On the one hand, Ce3+ triggers ROS production via a Fenton-like reaction, inducing ferroptosis in tumor cells. On the other hand, IR780 accumulates in mitochondria and disrupts mitochondrial function upon laser irradiation, leading to tumor cell apoptosis. EGCG serves as a sensitizer, simultaneously enhancing the sensitivity of tumor cells to ferroptosis and photothermal therapy. After a single dose and three times of 808 nm laser irradiation for treatment, it has been observed that the nanoreactor induces dendritic cells (DCs) maturation, facilitates cytotoxic T lymphocyte infiltration, improves immunosuppressive microenvironment, activates the systemic immune system, and generates long-term immune memory. [Display omitted] • A mitochondria-targeted nanoreactor based on Ce3+ and EGCG was prepared. • EGCG could enhance the sensitivity of tumor to ferroptosis- photothermal therapy. • A single dose of IR780/Ce@EGCG/APT could significantly inhibite 4 T1 tumor growth. • The IR780/Ce@EGCG/APT could improve the immunosuppressive microenvironment. [ABSTRACT FROM AUTHOR]

Cancer therapeutic resistance as a common hallmark of cancer is often responsible for treatment failure and poor patient survival. Cancer stem-like cells (CSCs) are one of the main contributors to therapeutic resistance, cancer relapse and metastasis. Through screening from our in-house library of natural products, we found polyphyllin II (PPII) as a potent anti-CSC compound for triple-negative breast cancer (TNBC). To enhance anti-CSC selectivity and improve druggability of PPII, we leverage the liposome-mediated delivery technique for increasing solubility of PPII, and more significantly, attaining broader therapeutic window. Liposomal PPII demonstrates its marked potency to inhibit tumor growth, post-surgical recurrence and metastasis compared to commercial liposomal chemotherapeutics in the mouse models of CSC-enriched TNBC tumor. We further identify PPII as an inhibitor of the Ras-related nuclear (RAN) protein whose upregulated expression is correlated with poor clinical outcomes. The direct binding of PPII to RAN reduces TNBC stemness, thereby suppressing tumor progression. Our work offers a significance from drug discovery to drug delivery benefiting from liposome technique for targeted treatment of high-stemness tumor. [Display omitted] • PPII, a natural product, effectively eliminates CSC-like cell population. • Liposome delivery enhances anticancer selectivity and efficacy of PPII. • RAN is identified as novel target of PPII. • PPII binds RAN to reduce tumor stemness phenotype. [ABSTRACT FROM AUTHOR]

Controlled manufacturing and long-term stability are key challenges in the development and translation of nanomedicines. This is exemplified by the mRNA-nanoparticle vaccines against COVID-19, which require (ultra-)cold temperatures for storage and shipment. Various cryogenic protocols have been explored to prolong nanomedicine shelf-life. However, freezing typically induces high mechanical stress on nanoparticles, resulting in aggregation or destabilization, thereby limiting their performance and application. Hence, evaluating the impact of freezing and storing on nanoparticle properties already early-on during preclinical development is crucial. In the present study, we used prototypic π electron-stabilized polymeric micelles based on mPEG- b -p(HPMAm-Bz) block copolymers to macro- and microscopically study the effect of different cryoprotective excipients on nanoformulation properties like size and size distribution, as well as on freezing-induced aggregation phenomena via in-situ freezing microscopy. We show that sucrose, unlike trehalose, efficiently cryoprotected paclitaxel-loaded micelles, and we exemplify the impact of formulation composition for efficient cryoprotection. We finally establish microfluidic mixing to formulate paclitaxel-loaded micelles with sucrose as a cryoprotective excipient in a single production step and demonstrate their stability for 6 months at −20 °C. The pharmaceutical properties and preclinical performance (in terms of tolerability and tumor growth inhibition in a patient-derived triple-negative breast cancer xenograft mouse model) of paclitaxel-loaded micelles were successfully cryopreserved. Together, our efforts promote future pharmaceutical development and translation of π electron-stabilized polymeric micelles, and they illustrate the importance of considering manufacturing and storage stability issues early-on during nanomedicine development. [Display omitted] [ABSTRACT FROM AUTHOR]