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Background: Aside from the canonical role of PDL1 as a tumour surface-expressed immune checkpoint molecule, tumour-intrinsic PDL1 signals regulate non-canonical immunopathological pathways mediating treatment resistance whose significance, mechanisms, and therapeutic targeting remain incompletely understood. Recent reports implicate tumour-intrinsic PDL1 signals in the DNA damage response (DDR), including promoting homologous recombination DNA damage repair and mRNA stability of DDR proteins, but many mechanistic details remain undefined. Methods: We genetically depleted PDL1 from transplantable mouse and human cancer cell lines to understand consequences of tumour-intrinsic PDL1 signals in the DNA damage response. We complemented this work with studies of primary human tumours and inducible mouse tumours. We developed novel approaches to show tumour-intrinsic PDL1 signals in specific subcellular locations. We pharmacologically depleted tumour PDL1 in vivo in mouse models with repurposed FDA-approved drugs for proof-of-concept clinical translation studies. Results: We show that tumour-intrinsic PDL1 promotes the checkpoint kinase-2 (Chk2)-mediated DNA damage response. Intracellular but not surface-expressed PDL1 controlled Chk2 protein content post-translationally and independently of PD1 by antagonising PIRH2 E3 ligase-mediated Chk2 polyubiquitination and protein degradation. Genetic tumour PDL1 depletion specifically reduced tumour Chk2 content but not ATM, ATR, or Chk1 DDR proteins, enhanced Chk1 inhibitor (Chk1i) synthetic lethality in vitro in diverse human and murine tumour models, and improved Chk1i efficacy in vivo. Pharmacologic tumour PDL1 depletion with cefepime or ceftazidime replicated genetic tumour PDL1 depletion by reducing tumour Chk2, inducing Chk1i synthetic lethality in a tumour PDL1-dependent manner, and reducing in vivo tumour growth when combined with Chk1i. Conclusions: Our data challenge the prevailing surface PDL1 paradigm, elucidate important and previously unappreciated roles for tumour-intrinsic PDL1 in regulating the ATM/Chk2 DNA damage response axis and E3 ligase-mediated protein degradation, suggest tumour PDL1 as a biomarker for Chk1i efficacy, and support the rapid clinical potential of pharmacologic tumour PDL1 depletion to treat selected cancers. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) are a group of important molecules involved in the progression of various cancers, including colorectal cancer (CRC). Here, we aim to investigate the role and molecular mechanism of circ_0007422 in regulating CRC malignant progression. The expression levels of circ_0007422, miR-1256, and PDL1 were detected by qRT-PCR. Cell viability, proliferation, apoptosis, invasion, and self-replication ability were analyzed by CCK-8, EdU, flow cytometry, transwell, and spheroid formation experiments, respectively. Protein levels were determined by western blotting assay. CRC cells were co-cultured with CD8 + T cells, phytohemagglutinin-stimulated peripheral blood mononuclear cells (PBMCs), or cytokine-induced killer (CIK) cells in vitro, and CD8 + T-cell apoptosis, IFN-γ and TNF-α levels, and survival rate of CRC cells were analyzed to reveal the role of circ_0007422 in antitumor immunity. The relationship between miR-1256 and circ_0007422 or PDL1 was identified by a dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. A xenograft tumor model was established to verify the function of circ_0007422 in tumor growth in vivo. Immunohistochemistry (IHC) assay was used to detect positive expression rates of Ki67, E-cadherin, N-cadherin, and PDL1 expression in primary tumors from CRC cells. Circ_0007422 was upregulated in CRC tissues and cells and its knockdown inhibited proliferation, invasion, self-replication ability, and immune escape and promoted apoptosis of CRC cells. Additionally, circ_0007422 bound to miR-1256, which was identified to target PDL1. MiR-1256 inhibition reversed the effects of circ_0007422 knockdown on the tumor properties and immune escape of CRC cells. Moreover, miR-1256 introduction interacted with PDL1 to suppress proliferation, invasion, self-replication ability, and immune escape and promote apoptosis of CRC cells. Further, circ_0007422 knockdown hampered tumorigenesis of CRC cells in vivo. Circ_0007422 knockdown inhibited tumor property and immune escape of colorectal cancer through the miR-1256/PDL1 pathway, providing a potential novel therapeutic target for CRC. [ABSTRACT FROM AUTHOR]

Abstract Background Aside from the canonical role of PDL1 as a tumour surface-expressed immune checkpoint molecule, tumour-intrinsic PDL1 signals regulate non-canonical immunopathological pathways mediating treatment resistance whose significance, mechanisms, and therapeutic targeting remain incompletely understood. Recent reports implicate tumour-intrinsic PDL1 signals in the DNA damage response (DDR), including promoting homologous recombination DNA damage repair and mRNA stability of DDR proteins, but many mechanistic details remain undefined. Methods We genetically depleted PDL1 from transplantable mouse and human cancer cell lines to understand consequences of tumour-intrinsic PDL1 signals in the DNA damage response. We complemented this work with studies of primary human tumours and inducible mouse tumours. We developed novel approaches to show tumour-intrinsic PDL1 signals in specific subcellular locations. We pharmacologically depleted tumour PDL1 in vivo in mouse models with repurposed FDA-approved drugs for proof-of-concept clinical translation studies. Results We show that tumour-intrinsic PDL1 promotes the checkpoint kinase-2 (Chk2)-mediated DNA damage response. Intracellular but not surface-expressed PDL1 controlled Chk2 protein content post-translationally and independently of PD1 by antagonising PIRH2 E3 ligase-mediated Chk2 polyubiquitination and protein degradation. Genetic tumour PDL1 depletion specifically reduced tumour Chk2 content but not ATM, ATR, or Chk1 DDR proteins, enhanced Chk1 inhibitor (Chk1i) synthetic lethality in vitro in diverse human and murine tumour models, and improved Chk1i efficacy in vivo. Pharmacologic tumour PDL1 depletion with cefepime or ceftazidime replicated genetic tumour PDL1 depletion by reducing tumour Chk2, inducing Chk1i synthetic lethality in a tumour PDL1-dependent manner, and reducing in vivo tumour growth when combined with Chk1i. Conclusions Our data challenge the prevailing surface PDL1 paradigm, elucidate important and previously unappreciated roles for tumour-intrinsic PDL1 in regulating the ATM/Chk2 DNA damage response axis and E3 ligase-mediated protein degradation, suggest tumour PDL1 as a biomarker for Chk1i efficacy, and support the rapid clinical potential of pharmacologic tumour PDL1 depletion to treat selected cancers.

Aim – to evaluate myeloid-derived suppressor cell (MDSC) subset counts and their suppressor potential in axial spondyloarthritis (axSpA) patients, as well as to analyze changes in the studied parameters in biological therapy (BT).Materials and methods. The study included 50 axSpA patients receiving 1st line therapy (non-steroidal anti-inflammatory drugs ±sulfasalazine/methotrexate) and 44 ageand sex-related healthy donors. Eight patients were initiated with BT (TNFαor IL-17 inhibitors). Peripheral blood granulocytic (G-MDSC), monocytic (M-MDSC) MDSCs, early-stage differentiation MDSCs (E-MDSC), and inhibitory molecule expression (PDL1, Arg-1, and IDO) were evaluated by flow cytometry.Results. The axSpA patients were characterized by increased G-MDSC counts (р

Case report: A 55-year-old male patient developed a mass in the left inguinal area with left lower limb swelling and first visited a local hospital 3 months earlier because of unrelieved pain. An MRI scan suggested left suprapubic branch and left acetabular bone destruction, abnormal soft tissue signals within the iliopsoas muscle of the anterior edge of the left iliac bone, and enlarged lymph nodes in the left iliac fossa and left inguinal region. The patient subsequently underwent left pelvic lesion open biopsy and inguinal lymph node resection biopsy. According to pathological reports, the left inguinal mass was considered to be a malignant tumor of cutaneous accessory origin (pilomatrix carcinoma) with extensive vitreous changes. The suprapupubis branch mass was considered to be a bone metastatic pilomatrix carcinoma. Immunohistochemistry (IHC) revealed a PDL1 combined positive score (CPS) of 8. DNA next-generation sequencing (NGS) showed CDKN2A L65Rfs*53 mutation. The patient received three cycles of gemcitabine and nedaplatin. However, the lesion progressed. Conclusion: Chemotherapy is not effective for treating pilomatrix carcinoma. PDL1 antibodies and CDK4/6 inhibitors might be treatment options for pilomatrix carcinoma. [ABSTRACT FROM AUTHOR]

Introduction: Clear cell renal cell carcinoma (ccRCC) is characterized by a predominant metabolic reprogramming triggering energy production by anaerobic glycolysis at the expense of oxydative phosphorylation. Ketogenic diet (KD), which consists of high fat and low carbohydrate intake, could bring required energy substrates to healthy cells while depriving tumor cells of glucose. Our objective was to evaluate the effect of KD on renal cancer cell tumor metabolism and growth proliferation. Methods: Growth cell proliferation and mitochondrial metabolism of ACHN and Renca renal carcinoma cells were evaluated under ketone bodies (KB) exposure. In vivo studies were performed with mice (nude or Balb/c) receiving a xenograft of ACHNcells orRencacells, respectively,andwerethensplit into2feedinggroups, fed either with standard diet or a 2:1 KDad libitum. To test the effect of KDassociated to immunotherapy, Balb/c mice were treated with anti-PDL1 mAb. Tumor growth was monitored. Results: In vitro, KB exposure was associated with a significant reduction of ACHN and Renca cell proliferation and viability, while increasing mitochondrial metabolism. In mice, KD was associated with tumor growth reduction and PDL-1 gene expression up-regulation. In Balb/c mice adjuvant KD was associated to a better response to anti-PDL-1 mAb treatment. Conclusion: KB reduced the renal tumor cell growth proliferation and improved mitochondrial respiration and biogenesis. KD also slowed down tumor growth of ACHNandRenca in vivo.WeobservedthatPDL-1was significantly overexpressed in tumor inmice under KD. Response to anti-PDL-1mAb was improved inmice under KD. Further studies are needed to confirm the therapeutic benefit of adjuvant KD combined with immunotherapy in patients with kidney cancer. [ABSTRACT FROM AUTHOR]

Non-small cell lung cancer (NSCLC) is one of the most common and fatal cancers in the world. Circular RNA (circRNA) can broadly participate in the initiation and progression of the NSCLC. However, the regulatory mechanisms of circRNA in NSCLC remain poorly understood. In present study, we aimed to explore the potential role of circ_0101675 in the progression of NSCLC. Quantitative real-time polymerase chain reaction was performed to examine the expression of circ_0101675, microRNA-607 (miR-607) and programmed cell death receptor ligand 1 (PDL1) in NSCLC tissues and cells. Cell count kit 8 assay, colony formation assay, wound healing assay, transwell assay, tube formation assay and flow cytometry were applied to examine NSCLC cell proliferation, migration, invasion, angiogenesis and apoptosis. NSCLC cells were co-cultured with peripheral blood mononuclear cells to assess immune response. The protein levels of PDL1 and proteins related to apoptosis were detected by western blotting. Dual-luciferase reporter assay and RNA immunoprecipitation assay were conducted to verify the direct target site between miR-607 and circ_0101675 or PDL1. The experiments in vivo were employed to explore the effects of circ_0101675 on tumor growth in NSCLC. Circ_0101675 and PDL1 were high-expressed, while miR-607 was low-expressed in NSCLC cells and cancer tissues. The suppression of circ_0101675 suppressed growth, migration, invasion, angiogenesis and immune escape in NSCLC cells. Mechanistically, we found that high level of circ_0101675 could upregulate PDL1 expression via sponging miR-607. Moreover, the down-regulation of circ_0101675 inhibited the growth of NSCLC tumors in vivo by enhancing miR-607 expression to decrease PDL1 expression. Taken together, our results suggested that circ_0101675 might promote the proliferation, migration, invasion, and immune evasion abilities of NSCLC through miR-607/PDL1 axis. [ABSTRACT FROM AUTHOR]

Introduction: Programmed death‐ligand 1 (PD‐L1) expression is an immune evasion mechanism that has been demonstrated in many tumors and is commonly associated with a poor prognosis. Over the years, anti‐PD‐L1 agents have gained attention as novel anticancer therapeutics that induce durable tumor regression in numerous malignancies. They may be a new treatment choice for neurofibromatosis type 2 (NF2) patients. Aims: The aims of this study were to detect the expression of PD‐L1 in NF2‐associated meningiomas, explore the effect of PD‐L1 downregulation on tumor cell characteristics and T‐cell functions, and investigate the possible pathways that regulate PD‐L1 expression to further dissect the possible mechanism of immune suppression in NF2 tumors and to provide new treatment options for NF2 patients. Results: PD‐L1 is heterogeneously expressed in NF2‐associated meningiomas. After PD‐L1 knockdown in NF2‐associated meningioma cells, tumor cell proliferation was significantly inhibited, and the apoptosis rate was elevated. When T cells were cocultured with siPD‐L1‐transfected NF2‐associated meningioma cells, the expression of CD69 on both CD4+ and CD8+ T cells was partly reversed, and the capacity of CD8+ T cells to kill siPD‐L1‐transfected tumor cells was partly restored. Results also showed that the PI3K–AKT–mTOR pathway regulates PD‐L1 expression, and the mTOR inhibitor rapamycin rapidly and persistently suppresses PD‐L1 expression. In vivo experimental results suggested that anti‐PD‐L1 antibody may have a synergetic effect with the mTOR inhibitor in reducing tumor cell proliferation and that reduced PD‐L1 expression could contribute to antitumor efficacy. Conclusions: Targeting PD‐L1 could be helpful for restoring the function of tumor‐infiltrating lymphocytes and inducing apoptosis to inhibit tumor proliferation in NF2‐associated meningiomas. Dissecting the mechanisms of the PD‐L1‐driven tumorigenesis of NF2‐associated meningioma will help to improve our understanding of the mechanisms underlying tumor progression and could facilitate further refinement of current therapies to improve the treatment of NF2 patients. [ABSTRACT FROM AUTHOR]

Emerging evidence indicates the critical roles of circular RNAs in the development of multiple cancers, containing hepatocellular carcinoma (HCC). Herein, our present research reported the biological function and mechanism of circ_0027791 in HCC progression. Circ_0027791, microRNA‐496 (miR‐496), programmed cell death ligand 1 (PDL1), and methyltransferase‐like 3 (METTL3) levels were detected by real‐time quantitative polymerase chain reaction (RT‐qPCR). Cell viability, proliferation, invasion, and sphere formation ability were detected using 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2‐H‐tetrazolium bromide, 5‐ethynyl‐2′‐deoxyuridine, transwell, and sphere formation assays. Macrophage polarization was detected using flow cytometry assay. To understand the role of circ_0027791 during the immune escape, HCC cells were cocultured with peripheral blood mononuclear cells or cytokine‐induced killer (CIK) cells in vitro. A xenograft mouse model was applied to assess the function of circ_0027791 in vivo. After prediction using circinteractome and miRDB, the binding between miR‐496 and circ_0027791 or PDL1 was validated based on a dual‐luciferase reporter assay. Interaction between METTL3 and circ_0027791 was determined using methylated RNA immunoprecipitation (MeRIP)‐qPCR, RIP‐qPCR, and RNA pull‐down assays. Circ_0027791, PDL1, and METTL3 expression were upregulated, and miR‐496 was decreased in HCC patients and cells. Moreover, circ_0027791 knockdown might repress proliferation, invasion, sphere formation, M2 macrophage polarization, and antitumor immune response. Circ_0027791 knockdown repressed HCC tumor growth in vivo. In mechanism, circ_0027791 functioned as a sponge for miR‐496 to increase PDL1 expression. In addition, METTL3 mediated the m6A methylation of circ_0027791 and stabilized its expression. METTL3‐induced circ_0027791 facilitated HCC cell progression partly regulating the miR‐496/PDL1 axis, which provided a new prognostic and therapeutic marker for HCC. [ABSTRACT FROM AUTHOR]

Abstract Background Active targeting by surface-modified nanoplatforms enables a more precise and elevated accumulation of nanoparticles within the tumor, thereby enhancing drug delivery and efficacy for a successful cancer treatment. However, surface functionalization involves complex procedures that increase costs and timelines, presenting challenges for clinical implementation. Biomimetic nanoparticles (BNPs) have emerged as unique drug delivery platforms that overcome the limitations of actively targeted nanoparticles. Nevertheless, BNPs coated with unmodified cells show reduced functionalities such as specific tumor targeting, decreasing the therapeutic efficacy. Those challenges can be overcome by engineering non-patient-derived cells for BNP coating, but these are complex and cost-effective approaches that hinder their wider clinical application. Here we present an immune-driven strategy to improve nanotherapeutic delivery to tumors. Our unique perspective harnesses T-cell exhaustion and tumor immune evasion to develop a groundbreaking new class of BNPs crafted from exhausted T-cells (NExT) of triple-negative breast cancer (TNBC) patients by specific culture methods without sophisticated engineering. Methods NExT were generated by coating PLGA (poly(lactic-co-glycolic acid)) nanoparticles with TNBC-derived T-cells exhausted in vitro by acute activation. Physicochemical characterization of NExT was made by dynamic light scattering, electrophoretic light scattering and transmission electron microscopy, and preservation and orientation of immune checkpoint receptors by flow cytometry. The efficacy of chemotherapy-loaded NExT was assessed in TNBC cell lines in vitro. In vivo toxicity was made in CD1 mice. Biodistribution and therapeutic activity of NExT were determined in cell-line- and autologous patient-derived xenografts in immunodeficient mice. Results We report a cost-effective approach with a good performance that provides NExT naturally endowed with immune checkpoint receptors (PD1, LAG3, TIM3), augmenting specific tumor targeting by engaging cognate ligands, enhancing the therapeutic efficacy of chemotherapy, and disrupting the PD1/PDL1 axis in an immunotherapy-like way. Autologous patient-derived NExT revealed exceptional intratumor accumulation, heightened chemotherapeutic index and efficiency, and targeted the tumor stroma in a PDL1+ patient-derived xenograft model of triple-negative breast cancer. Conclusions These advantages underline the potential of autologous patient-derived NExT to revolutionize tailored adoptive cancer nanotherapy and chemoimmunotherapy, which endorses their widespread clinical application of autologous patient-derived NExT.

Background: Active targeting by surface-modified nanoplatforms enables a more precise and elevated accumulation of nanoparticles within the tumor, thereby enhancing drug delivery and efficacy for a successful cancer treatment. However, surface functionalization involves complex procedures that increase costs and timelines, presenting challenges for clinical implementation. Biomimetic nanoparticles (BNPs) have emerged as unique drug delivery platforms that overcome the limitations of actively targeted nanoparticles. Nevertheless, BNPs coated with unmodified cells show reduced functionalities such as specific tumor targeting, decreasing the therapeutic efficacy. Those challenges can be overcome by engineering non-patient-derived cells for BNP coating, but these are complex and cost-effective approaches that hinder their wider clinical application. Here we present an immune-driven strategy to improve nanotherapeutic delivery to tumors. Our unique perspective harnesses T-cell exhaustion and tumor immune evasion to develop a groundbreaking new class of BNPs crafted from exhausted T-cells (NExT) of triple-negative breast cancer (TNBC) patients by specific culture methods without sophisticated engineering. Methods: NExT were generated by coating PLGA (poly(lactic-co-glycolic acid)) nanoparticles with TNBC-derived T-cells exhausted in vitro by acute activation. Physicochemical characterization of NExT was made by dynamic light scattering, electrophoretic light scattering and transmission electron microscopy, and preservation and orientation of immune checkpoint receptors by flow cytometry. The efficacy of chemotherapy-loaded NExT was assessed in TNBC cell lines in vitro. In vivo toxicity was made in CD1 mice. Biodistribution and therapeutic activity of NExT were determined in cell-line- and autologous patient-derived xenografts in immunodeficient mice. Results: We report a cost-effective approach with a good performance that provides NExT naturally endowed with immune checkpoint receptors (PD1, LAG3, TIM3), augmenting specific tumor targeting by engaging cognate ligands, enhancing the therapeutic efficacy of chemotherapy, and disrupting the PD1/PDL1 axis in an immunotherapy-like way. Autologous patient-derived NExT revealed exceptional intratumor accumulation, heightened chemotherapeutic index and efficiency, and targeted the tumor stroma in a PDL1+ patient-derived xenograft model of triple-negative breast cancer. Conclusions: These advantages underline the potential of autologous patient-derived NExT to revolutionize tailored adoptive cancer nanotherapy and chemoimmunotherapy, which endorses their widespread clinical application of autologous patient-derived NExT. [ABSTRACT FROM AUTHOR]

Background: Factors that could predict which patients will benefit from Immune Checkpoint Inhibitors (ICIs) are not fully understood. This study aimed to investigate the prognostic value of KRAS biomarker in patients with advanced non-small cell lung cancer (NSCLC) in relation to clinical characteristics, treatment response and PDL1 expression. Patients and methods: The study included 100 patients with NSCLC who received immunotherapy with or without chemotherapy as 1st line treatment. In biopsy samples, the PDL1 biomarker expression rate and somatic mutations of KRAS gene were determined. Results: The mean age of the patients was 67 ± 8 years. Patients were all male and 66% were found with adenocarcinoma whereas 34% with squamous cell carcinoma. The KRAS G12C mutation was found with the highest percentage (73%). In the Kaplan-Meier survival analysis, patients with PDL1 > 49% in combination with a negative KRAS result had a median overall survival of 40 months compared to patients with a positive KRAS result (9 months, p < 0.05). In addition, patients diagnosed with adenocarcinoma, PDL1 < 49% and negative KRAS result had a median overall survival of 39 months compared to patients with a positive result (28 months, p < 0.05). Conclusions: Our study suggests that the presence of KRAS mutations in advanced NSCLC patients has a poor prognostic value, regardless of their PDL1 expression values, after receiving immunotherapy as first-line treatment. [ABSTRACT FROM AUTHOR]

Recent years have seen the recognition and establishment of numerous subtypes of renal cell carcinoma (RCC), including adoption of an entire category of "molecularly defined renal carcinomas" in the fifth Edition of World Health Organization Classification. To add value, new diagnostic entities should be clinicopathologically distinct, or better, imply specific management and treatment angles, especially if adjunctive testing is needed for diagnosis. One such promising future treatment angle for a molecularly defined subtype, TFEB -amplified RCC, is immunotherapy, for which recent scholarship has demonstrated frequent expression of PD-L1. Herein, we report a case of metastatic TFEB -amplified RCC, where the patient experienced a long-term, complete response to PDL1-directed therapy, which had been serendipitously used years ago under a renal tumor subtype-agnostic indication. This promising experience suggests formal exploration of immunotherapy for these tumors. [ABSTRACT FROM AUTHOR]

Immuno-oncology research has brought to light the paradoxical role of immune cells in the induction and elimination of cancer. Programmed cell death protein 1 (PD1), expressed by tumor-infiltrating lymphocytes, and programmed cell death ligand 1 (PDL1), expressed by tumor cells, are immune checkpoint proteins that regulate the antitumor adaptive immune response. This study aimed to validate commercially available PDL1 antibodies in canine tissue and then, applying standardized methods and scoring systems used in human pathology, evaluate PDL1 immunopositivity in different types of canine tumors. To demonstrate cross-reactivity, a monoclonal antibody (22C3) and polyclonal antibody (cod. A1645) were tested by western blot. Cross-reactivity in canine tissue cell extracts was observed for both antibodies; however, the polyclonal antibody (cod. A1645) demonstrated higher signal specificity. Canine tumor histotypes were selected based on the human counterparts known to express PDL1. Immunohistochemistry was performed on 168 tumors with the polyclonal anti-PDL1 antibody. Only membranous labeling was considered positive. PDL1 labeling was detected both in neoplastic and infiltrating immune cells. The following tumors were immunopositive: melanomas (17 of 17; 100%), renal cell carcinomas (4 of 17; 24%), squamous cell carcinomas (3 of 17; 18%), lymphomas (2 of 14; 14%), urothelial carcinomas (2 of 18; 11%), pulmonary carcinomas (2 of 20; 10%), and mammary carcinomas (1 of 31; 3%). Gastric (0 of 10; 0%) and intestinal carcinomas (0 of 24; 0%) were negative. The findings of this study suggest that PDL1 is expressed in some canine tumors, with high prevalence in melanomas. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) play a role in the emergence and progression of several human tumors, including luminal B breast cancer (BC). The biological functions and potential mechanisms of lncRNA myocardial infarction-associated transcripts (MIAT) in luminal B BC, on the contrary, are unknown. In this work, we used UALCAN database analysis to find high expression of lncRNA MIAT in luminal BC tissues and also confirmed high levels of lncRNA MIAT expression in luminal B BC tissues and cells. In vitro knockdown of MIAT inhibited the proliferation, migration, and invasion of BT474 cells. In addition, we found that miR-150-5p levels were significantly reduced in luminal B BC specimens and cells, and miR-150-5p levels were significantly increased when MIAT was knocked down. And TIMER database analysis showed that MIAT was positively associated with PDL1. Through bioinformatic tools and in vitro experiments, lncRNA MIAT could function as a competitive endogenous RNA (CeRNA) to further regulate programmed cell death ligand 1 (PDL1) expression by directly sponging miR-150-5p. In conclusion, our data suggest that MIAT, an oncogene, may sponge miR-150-5p to regulate PDL1 expression and affect proliferation, migration, and invasion in luminal B BC in vitro. [ABSTRACT FROM AUTHOR]

Programmed cell death‐ligand 1 (PDL1) is a transmembrane protein that is characterized as an immune regulatory molecule. We recently developed a recombinant single‐chain fragment of variable domain (scFv) against PDL1, which showed high binding efficiency to purified recombinant PDL1 protein. However, at that time, proof‐of‐concept data for the effect of scFv using PDL1‐expressing cells was lacking. In this study, we conducted two kinds of cell‐based immunoassays, western blotting and enzyme‐linked immunosorbent assay, using anti‐PDL1 scFv. The results indicate that scFv can selectively and sensitively detect PDL1 from PDL1 positive human cancer cell lines. Our findings suggest that scFv could be used as a potential PDL1 inhibitor agent and probe for cell‐based immunoassays to detect PDL1. [ABSTRACT FROM AUTHOR]

Introduction: Immunotherapy by blocking immune checkpoints programmed death/ligand (PD1/PDL1) and cytotoxic T-lymphocyte-associated protein 4(CTLA4) has emerged as new therapeutic targets in cancer. However, their efficacy has been limited due to resistance. A new- checkpoint V-domain Ig-containing suppressor of T cell activation (VISTA) has appeared, but the use of its inhibition effect in combination with antibodies targeting PDL1/PD1and CTLA4 has not been reported in ovarian cancer. Methods: In this study, we investigated the expressions of VISTA, CTLA4, and PDL1 using immunohistochemistry (IHC)on 135 Formalin-Fixed Paraffin-Embedded (FFPE)tissue samples of High-grade serous carcinoma (HGSOC). VISTA, CTLA4, PDL1, PD1, CD8, CD4, and FOXP3 mRNA extracted from 429 patients with ovarian cancer in the Cancer Genome Atlas (TCGA) database was included as a validation cohort. Correlations between these checkpoints, tumor-infiltrating- lymphocytes (TILs), and survival were analyzed. Results and discussion: CTLA4 was detectable in 87.3% of samples, VISTA in 64.7%, PD1 in 56.7%, and PDL1 in 48.1%. PDL1 was the only tested protein associated with an advanced stage (p=0.05). VISTA was associated with PDL1, PD1, and CTLA4 expressions (p=0.005, p=0.001, p=0.008, respectively), consistent with mRNA level analysis from the TCGA database. Univariate analyses showed only VISTA expression (p=0.04) correlated with overall survival (OS). Multivariate analyses showed that VISTA expression (p=0.01) and the coexpression of VISTA+/CTLA4+/PD1+ (p=0.05) were associated with better OS independently of the clinicopathological features. Kaplan-Meier analysis showed that the coexpression of the VISTA+/CTLA4+/PDL1+ and VISTA+/CTLA4+/PD1+ checkpoints on tumor cells (TCs)were associated with OS (p=0.02 and p<0.001; respectively). VISTA+/CTLA4+/PD1+ in TCs and CD4+/CD8+TILs were associated with better 2-yer OS. This correlation may refer to the role of VISTA as a receptor in the TCs and not in the immune cells. Thus, targeting combination therapy blocking VISTA, CTLA4, and PD1 could be a novel and attractive strategy for HGSOC treatment, considering the ambivalent role of VISTA in the HGSOC tumor cells. [ABSTRACT FROM AUTHOR]

Simple Summary: Patients with oncogene-addicted lung cancers that have developed resistance to oral targeted therapy have limited treatment options. Several studies have shown conflicting results in this setting, but those using Bevacizumab and Paclitaxel in combination with immunotherapy (ABCP) have consistently shown activity. Spread to the brain is common, but it is not known how many patients with brain metastases are amenable to chemo-immunotherapy, and its effect in this patient group has not been reported to date. We present here our retrospective real-life experience in patients treated with ABCP. Our results in 34 patients underlined that spread to the brain occurred in 19 patients (56%), 17 of them without previous brain radiotherapy. In these 19 patients, chemo-immunotherapy triggered frequent and quick responses inside and outside the brain and showed similar outcomes to those shown in patients with smoking-related lung cancer and previously untreated brain metastases. Contrary to Pemetrexed-containing chemo-immunotherapy studies, Atezolizumab, Bevacizumab, Carboplatin, and Paclitaxel (ABCP) treatment has consistently shown clinical benefit in prospective studies in patients with lung cancer and actionable mutations, where intracranial metastases are common. Here, we aimed to describe the real-life population of patients fit to receive ABCP after targeted therapy and quantify its clinical effect in patients with brain metastases. Patients treated in Cheshire and Merseyside between 2019 and 2022 were identified. Data were collected retrospectively. A total of 34 patients with actionable EGFR or ALK alterations had treatment with a median age of 59 years (range 32–77). The disease control rate was 100% in patients with PDL1 ≥ 1% (n = 10). In total, 19 patients (56%) had brain metastases before starting ABCP, 17 (50%) had untreated CNS disease, and 4 (22%) had PDL1 ≥ 1%. The median time to symptom improvement was 12.5 days (range 4–21 days), with 74% intracranial disease control rates and 89.5% synchronous intracranial (IC) and extracranial (EC) responses. IC median Progression Free Survival (mPFS) was 6.48 months, EC mPFS was 10.75 months, and median Overall Survival 11.47 months. ABCP in real-life patients with brain metastases (treated or untreated) was feasible and showed similar efficacy to that described in patients without actionable mutations treated with upfront chemo-immunotherapy. [ABSTRACT FROM AUTHOR]

We designed, produced, and purified a novel IgG1-like, bispecific antibody (bsAb) directed against B-cell maturation antigen (BCMA), expressed by multiple myeloma (MM) cells, and an immune checkpoint inhibitor (ICI), PDL1, expressed in the MM microenvironment. The BCMA×PDL1 bsAb was fully characterized in vitro. BCMA×PDL1 bound specifically and simultaneously, with nM affinity, to both native membrane-bound antigens and to the recombinant soluble antigen fragments, as shown by immunophenotyping analyses and surface plasmon resonance (SPR), respectively. The binding affinity of bsAb for PDL1 and BCMA was similar to each other, but PDL1 affinity was about 10-fold lower in the bsAb compared to parent mAb, probably due to the steric hindrance associated with the more internal anti-PDL1 Fab. The bsAb was also able to functionally block both antigen targets with IC50 in the nM range. The bsAb Fc was functional, inducing human-complement-dependent cytotoxicity as well as ADCC by NK cells in 24 h killing assays. Finally, BCMA×PDL1 was effective in 7-day killing assays with peripheral blood mononuclear cells as effectors, inducing up to 75% of target MM cell line killing at a physiologically attainable, 6 nM, concentration. These data provide the necessary basis for future optimization and in vivo testing of this novel bsAb. [ABSTRACT FROM AUTHOR]

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Abstract Background The impact of immune checkpoint inhibitors (ICIs) based treatments on non-small cell lung cancers (NSCLCs) with RET fusions remains poorly understood. Methods We screened patients with RET fusions at the First Affiliated Hospital of Zhengzhou University and included those who were treated with ICIs based regimens for further analysis. We evaluated clinical indicators including objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). Results A total of 232 patients with RET fusions were included in the study. Of these, 129 patients had their programmed death-ligand 1 (PDL1) expression levels tested, with 22 patients (17.8%) having a PDL1 level greater than or equal to 50%. Additionally, tumor mutational burden (TMB) status was evaluated in 35 patients, with the majority (30/35, 85.8%) having a TMB of less than 10 mutations per megabase. Out of the 38 patients treated with ICI based regimens, the median PFS was 5 months (95% confidence interval [CI]: 2.4–7.6 months) and the median OS was 19 months (95% CI: 9.7–28.3 months) at the time of data analysis. Stratification based on treatment lines did not show any significant differences in OS (18 vs. 19 months, p = 0.63) and PFS (6 vs. 5 months, p = 0.86). The ORR for patients treated with ICIs was 26.3%. Furthermore, no significant differences were found for PFS (p = 0.27) and OS (p = 0.75) between patients with positive and negative PDL1 expression. Additionally, there was no significant difference in PD-L1 levels (p = 0.10) between patients who achieved objective response and those who did not. Conclusions Patients with RET fusion positive NSCLCs may not benefit from ICI based regimens and therefore should not be treated with ICIs in clinical practice.

Objectives: To evaluate the effects of platinum-based neoadjuvant chemotherapy (NACT) on the STING/IFN pathway and tumor-infiltrating lymphocytes (TILs) in non-small cell lung cancer (NSCLC), as well as clinicopathological factors affecting patient survival. Materials and methods: A total of 68 patients aged 34-77 years with NSCLC who received neoadjuvant chemotherapy and surgical treatment from March 2012 to February 2019 were reviewed, and the clinical pathological data and paired tissue specimens before and after NACT were collected. Immunohistochemistry and immunofluorescence were used to detect the protein levels of STING, PD-L1 and IFN-b, and the infiltration density of CD3+ TILs and CD8+TILs. The correlation between the expression of STING, PD-L1, IFN-b and the infiltration density of CD3+ TILs and CD8+ TILs as well as the clinicopathological characteristics before and after NACT was analyzed. The relationship between the related indexes, clinicopathological features and prognosis was also discussed. Results: NACT increased the expression of STING, IFN-β and PD-L1 in tumor cells, and the infiltration of CD3+ and CD8+ TILs. In addition, ypTNM stage, ypN stage, changes in CD3+ TILs and in PD-L1 were associated with DFS (disease-free survival). CD3+ TILs changes and ypN stage were associated with OS (overall survival). Notably, ypN stage and CD3+ TILs changes were independent prognostic factors for DFS and OS. Conclusion: NACT stimulates STING/IFN-β pathway, promotes infiltration of CD3+ and CD8+ TILs, triggers innate and adaptive immunity, and also upregulates PD-L1, which complemented the rationale for neoadjuvant chemotherapy in combination with immunotherapy. In addition, DFS was longer in patients with ypTNM I, ypN0-1, and elevated CD3+TILs after NACT. Patients with ypN0 and elevated CD3+ TILs after NACT had better OS benefits. [ABSTRACT FROM AUTHOR]

Background: The impact of immune checkpoint inhibitors (ICIs) based treatments on non-small cell lung cancers (NSCLCs) with RET fusions remains poorly understood. Methods: We screened patients with RET fusions at the First Affiliated Hospital of Zhengzhou University and included those who were treated with ICIs based regimens for further analysis. We evaluated clinical indicators including objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS). Results: A total of 232 patients with RET fusions were included in the study. Of these, 129 patients had their programmed death-ligand 1 (PDL1) expression levels tested, with 22 patients (17.8%) having a PDL1 level greater than or equal to 50%. Additionally, tumor mutational burden (TMB) status was evaluated in 35 patients, with the majority (30/35, 85.8%) having a TMB of less than 10 mutations per megabase. Out of the 38 patients treated with ICI based regimens, the median PFS was 5 months (95% confidence interval [CI]: 2.4–7.6 months) and the median OS was 19 months (95% CI: 9.7–28.3 months) at the time of data analysis. Stratification based on treatment lines did not show any significant differences in OS (18 vs. 19 months, p = 0.63) and PFS (6 vs. 5 months, p = 0.86). The ORR for patients treated with ICIs was 26.3%. Furthermore, no significant differences were found for PFS (p = 0.27) and OS (p = 0.75) between patients with positive and negative PDL1 expression. Additionally, there was no significant difference in PD-L1 levels (p = 0.10) between patients who achieved objective response and those who did not. Conclusions: Patients with RET fusion positive NSCLCs may not benefit from ICI based regimens and therefore should not be treated with ICIs in clinical practice. [ABSTRACT FROM AUTHOR]

Tumor-associated macrophages (TAMs) play a key role in inducing an immunosuppressive tumor microenvironment (TME) and cancer immune escape. We previously revealed that PDL1 (a key immune checkpoint) was upregulated in TAMs and induced M2 polarization, highlighting PDL1 in TAMs as a promising cancer therapeutic target. In this study, we developed an engineered milk exosome (mExo) system decorated with M2pep (an M2 macrophage binding peptide) and 7D12 (an anti-EGFR nanobody) (7D12-mExo-M2pep-siPDL1) to specifically deliver siPDL1 into M2 TAMs. A series of in vitro and in vivo assays showed that the dually targeted engineered mExos efficiently delivered siPDL1 into M2 TAMs and repolarized them into M1 macrophages, restoring CD8+ T cell immune activity and remodeling TME. Importantly, systemically administered 7D12-mExo-M2pep-siPDL1 showed efficient single-agent antitumor activity, resulting in nearly 90% tumor growth inhibition in a mouse model of orthotopic epidermal growth factor receptor (EGFR) cancer. Collectively, our study indicates that PDL1 is a promising target for TAM-based cancer immunotherapy, and our engineered mExo-based nanomedicine represents a novel tool for specifically targeting M2 TAMs, distinguishing this novel therapeutic method from other TAM-targeting therapies and highlighting its promising clinical potential. [Display omitted] • An engineered mExo system decorated with M2pep and EGFR nanobody was developed. • PDL1 is a promising target for TAM-based cancer immunotherapy. • The engineered mExo system specifically deliver siPDL1 into M2 TAMs. • The engineered mExo system showed efficient antitumor activity for EGFR+ tumors. [ABSTRACT FROM AUTHOR]

Simple Summary: Head and neck cancer (HNC) is an aggressive form of cancer that affects hundreds of thousands of people worldwide and has a relatively poor prognosis. In the last decade, new therapeutics designed to enhance a patient's immune system have been approved for use, but HNC has developed many different methods that help it escape the immune system. The existing immunotherapies target only one of these mechanisms, allowing HNC to utilize others to continue to elude the immune system. This review details the various strategies used by HNC to escape the immune response, dividing them into four general categories: evade, resist, inhibit, and recruit. Each of the immune escape mechanisms represents a potential immunotherapy target that could be used to treat HNC. Head and neck cancers (HNCs) arise from the mucosal lining of the aerodigestive tract and are often associated with alcohol use, tobacco use, and/or human papillomavirus (HPV) infection. Over 600,000 new cases of HNC are diagnosed each year, making it the sixth most common cancer worldwide. Historically, treatments have included surgery, radiation, and chemotherapy, and while these treatments are still the backbone of current therapy, several immunotherapies have recently been approved by the Food and Drug Administration (FDA) for use in HNC. The role of the immune system in tumorigenesis and cancer progression has been explored since the early 20th century, eventually coalescing into the current three-phase model of cancer immunoediting. During each of the three phases—elimination, equilibrium, and escape—cancer cells develop and utilize multiple strategies to either reach or remain in the final phase, escape, at which point the tumor is able to grow and metastasize with little to no detrimental interference from the immune system. In this review, we summarize the many strategies used by HNC to escape the immune system, which include ways to evade immune detection, resist immune cell attacks, inhibit immune cell functions, and recruit pro-tumor immune cells. [ABSTRACT FROM AUTHOR]

Background/Aim: Immune checkpoint inhibitors (ICI) and tumor-infiltrating lymphocytes (TILs) for cancer treatment in clinical oncology have revolutionized patient care. However, no gold standard exists for the criteria of analytical validity of TILs of different types of cancer. Materials and Methods: Clinicopathological data from 60 patients with endometrioid carcinoma (EC) who had undergone surgical treatment at the Gyeongsang National University Hospital between January 2002 and December 2009, were investigated. The programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PDL1) expression levels were characterized by immunohistochemical staining patterns, and the interpretations derived from machine learning morphometric analysis (Genie) and the pathologists' assessments were compared. In solid tumors, pathologists assessed the proportion of positive cells in each core of the tissue microarray. For Genie, the proportion of positive cells in the entire core and the number of positive cells per 1 mm² were used. Results: Both the pathologists and Genie identified the same trend in association with tumor size, with significant differences (p=0.026, p=0.033). Genie expression showed a significant association with PD1 expression, and pathologists identified a significant association with PDL1 expression in immune cells. Conclusion: The PD1 expression levels identified in immune cells of EC specimens were similar between the pathologists and Genie, suggesting that there is little resistance to the introduction of morphometric analysis. To our knowledge, this is the first study to introduce and validate machine learning as an integrated method for predicting prognosis and treatment based on PD1 expression in EC tumor microenvironments. [ABSTRACT FROM AUTHOR]

Case reportA 55-year-old male patient developed a mass in the left inguinal area with left lower limb swelling and first visited a local hospital 3 months earlier because of unrelieved pain. An MRI scan suggested left suprapubic branch and left acetabular bone destruction, abnormal soft tissue signals within the iliopsoas muscle of the anterior edge of the left iliac bone, and enlarged lymph nodes in the left iliac fossa and left inguinal region. The patient subsequently underwent left pelvic lesion open biopsy and inguinal lymph node resection biopsy. According to pathological reports, the left inguinal mass was considered to be a malignant tumor of cutaneous accessory origin (pilomatrix carcinoma) with extensive vitreous changes. The suprapupubis branch mass was considered to be a bone metastatic pilomatrix carcinoma. Immunohistochemistry (IHC) revealed a PDL1 combined positive score (CPS) of 8. DNA next-generation sequencing (NGS) showed CDKN2A L65Rfs*53 mutation. The patient received three cycles of gemcitabine and nedaplatin. However, the lesion progressed.ConclusionChemotherapy is not effective for treating pilomatrix carcinoma. PDL1 antibodies and CDK4/6 inhibitors might be treatment options for pilomatrix carcinoma.

IntroductionClear cell renal cell carcinoma (ccRCC) is characterized by a predominant metabolic reprogramming triggering energy production by anaerobic glycolysis at the expense of oxydative phosphorylation. Ketogenic diet (KD), which consists of high fat and low carbohydrate intake, could bring required energy substrates to healthy cells while depriving tumor cells of glucose. Our objective was to evaluate the effect of KD on renal cancer cell tumor metabolism and growth proliferation.MethodsGrowth cell proliferation and mitochondrial metabolism of ACHN and Renca renal carcinoma cells were evaluated under ketone bodies (KB) exposure. In vivo studies were performed with mice (nude or Balb/c) receiving a xenograft of ACHN cells or Renca cells, respectively, and were then split into 2 feeding groups, fed either with standard diet or a 2:1 KD ad libitum. To test the effect of KD associated to immunotherapy, Balb/c mice were treated with anti-PDL1 mAb. Tumor growth was monitored.ResultsIn vitro, KB exposure was associated with a significant reduction of ACHN and Renca cell proliferation and viability, while increasing mitochondrial metabolism. In mice, KD was associated with tumor growth reduction and PDL-1 gene expression up-regulation. In Balb/c mice adjuvant KD was associated to a better response to anti-PDL-1 mAb treatment.ConclusionKB reduced the renal tumor cell growth proliferation and improved mitochondrial respiration and biogenesis. KD also slowed down tumor growth of ACHN and Renca in vivo. We observed that PDL-1 was significantly overexpressed in tumor in mice under KD. Response to anti-PDL-1 mAb was improved in mice under KD. Further studies are needed to confirm the therapeutic benefit of adjuvant KD combined with immunotherapy in patients with kidney cancer.

IntroductionImmunotherapy by blocking immune checkpoints programmed death/ligand (PD1/PDL1) and cytotoxic T-lymphocyte-associated protein 4(CTLA4) has emerged as new therapeutic targets in cancer. However, their efficacy has been limited due to resistance. A new- checkpoint V-domain Ig-containing suppressor of T cell activation (VISTA) has appeared, but the use of its inhibition effect in combination with antibodies targeting PDL1/PD1and CTLA4 has not been reported in ovarian cancer.MethodsIn this study, we investigated the expressions of VISTA, CTLA4, and PDL1 using immunohistochemistry (IHC)on 135 Formalin-Fixed Paraffin-Embedded (FFPE)tissue samples of High-grade serous carcinoma (HGSOC). VISTA, CTLA4, PDL1, PD1, CD8, CD4, and FOXP3 mRNA extracted from 429 patients with ovarian cancer in the Cancer Genome Atlas (TCGA) database was included as a validation cohort. Correlations between these checkpoints, tumor-infiltrating- lymphocytes (TILs), and survival were analyzed.Results and discussionCTLA4 was detectable in 87.3% of samples, VISTA in 64.7%, PD1 in 56.7%, and PDL1 in 48.1%. PDL1 was the only tested protein associated with an advanced stage (p=0.05). VISTA was associated with PDL1, PD1, and CTLA4 expressions (p=0.005, p=0.001, p=0.008, respectively), consistent with mRNA level analysis from the TCGA database. Univariate analyses showed only VISTA expression (p=0.04) correlated with overall survival (OS). Multivariate analyses showed that VISTA expression (p=0.01) and the coexpression of VISTA+/CTLA4+/PD1+ (p=0.05) were associated with better OS independently of the clinicopathological features. Kaplan-Meier analysis showed that the coexpression of the VISTA+/CTLA4+/PDL1+ and VISTA+/CTLA4+/PD1+ checkpoints on tumor cells (TCs)were associated with OS (p=0.02 and p

Lung cancer is a leading cause of cancer-related deaths globally, includes small cell lung cancer (SCLC), characterized by its aggressive nature and advanced disease at diagnosis. However, the identification of reliable biomarkers for SCLC has proven challenging, as no consistent predictive biomarker has been established. Nonetheless, certain tumor-associated antigens, including programmed death-ligand 1 (PDL1) and Delta-Like Ligand 3 (DLL3), show promise for targeted antibody-based immunotherapy. To ensure optimal patient selection, it remains crucial to comprehend the relationship between PDL1 and DLL3 expression and clinicopathological characteristics in SCLC. In this study, we investigated the expression patterns of PDL1 and DLL3 biomarkers in endobronchial samples from 44 SCLC patients, examining their association with clinical characteristics and survival. High PDL1 expression (>1%) was observed in 14% of patients, while the majority the SCLC patients (73%) exhibited high DLL3 expression (>75%). Notably, we found a positive correlation between high PDL1 expression (>1%) and overall survival. However, we did not observe any significant differences in the biomarkers expression concerning age, sex, disease status, smoking status, or distant metastases. Further subgroup analysis revealed that a high co-expression of both PDL1 (>1%) and DLL3 (100%) antigens was associated with improved overall survival. This suggests that SCLC expressing PDL1 and DLL3 antigens may exhibit increased sensitivity to therapy, indicating their potential as therapeutic targets. Thus, our findings provide novel insights into the simultaneous evaluation of PDL1 and DLL3 biomarkers in SCLC patients. These insights have significant clinical implications for therapeutic strategies, survival prediction, and development of combination immunotherapies.

RECQL is essential for genomic stability. Here, we evaluated RECQL in 449 pure ductal carcinomas in situ (DCIS), 152 DCIS components of mixed DCIS/invasive breast cancer (IBC) tumors, 157 IBC components of mixed DCIS/IBC and 50 normal epithelial terminal ductal lobular units (TDLUs). In 726 IBCs, CD8+, FOXP3+, IL17+, PDL1+, PD1+ T-cell infiltration (TILs) were investigated in RECQL deficient and proficient cancers. Tumor mutation burden (TMB) was evaluated in five RECQL germ-line mutation carriers with IBC by genome sequencing. Compared with normal epithelial cells, a striking reduction in nuclear RECQL in DCIS was evident with aggressive pathology and poor survival. In RECQL deficient IBCs, CD8+, FOXP3+, IL17+ or PDL1+ TILs were linked with aggressive pathology and shorter survival. In germline RECQL mutation carriers, increased TMB was observed in 4/5 tumors. We conclude that RECQL loss is an early event in breast cancer and promote immune cell infiltration.

We designed, produced, and purified a novel IgG1-like, bispecific antibody (bsAb) directed against B-cell maturation antigen (BCMA), expressed by multiple myeloma (MM) cells, and an immune checkpoint inhibitor (ICI), PDL1, expressed in the MM microenvironment. The BCMA×PDL1 bsAb was fully characterized in vitro. BCMA×PDL1 bound specifically and simultaneously, with nM affinity, to both native membrane-bound antigens and to the recombinant soluble antigen fragments, as shown by immunophenotyping analyses and surface plasmon resonance (SPR), respectively. The binding affinity of bsAb for PDL1 and BCMA was similar to each other, but PDL1 affinity was about 10-fold lower in the bsAb compared to parent mAb, probably due to the steric hindrance associated with the more internal anti-PDL1 Fab. The bsAb was also able to functionally block both antigen targets with IC50 in the nM range. The bsAb Fc was functional, inducing human-complement-dependent cytotoxicity as well as ADCC by NK cells in 24 h killing assays. Finally, BCMA×PDL1 was effective in 7-day killing assays with peripheral blood mononuclear cells as effectors, inducing up to 75% of target MM cell line killing at a physiologically attainable, 6 nM, concentration. These data provide the necessary basis for future optimization and in vivo testing of this novel bsAb.

Purpose: There is debate about the optimal management of borderline resectable (bRe) and resectable (Re) pancreatic ductal adenocarcinoma (PDAC). Both preclinical and clinical evidence showed that carbon ion radiotherapy (CIRT) produces superior control on radioresistant histologies compared to conventional photon beam radiotherapy (RT). However, so far there is a lack of data concerning the integration of CIRT in a multimodal approach with chemotherapy and surgery for bRe/Re., Methods: We recently presented the first analysis of a multicenter prospective phase II clinical study aimed at assessing the feasibility and effectiveness of a neoadjuvant chemotherapy + short course of CIRT followed by surgery and adjuvant chemotherapy in the management of bRe/Re PDAC. The study was terminated early due to low patient enrollment.Herein, we reported a post-hoc analysis focusing on toxicity, dosimetry and translational assessment., Results: In our experience, CIRT can be integrated into a multimodal treatment strategy for bRe/Re PDAC, alongside chemotherapy and surgery. A case of fatal liver failure occurring three months post-surgery has been documented, likely related to the combination approach. Although the treatment plans were satisfactory according to the Local Effect Model (LEM) model, recalculations using the modified Microdosimetric Kinetic Model (mMKM) revealed suboptimal target coverage. Additionally, we observed an increased expression of PD-L1 following CIRT., Conclusions: This multimodal approach was well tolerated; however, clinicians should carefully monitor for vascular disorders during follow-up and further investigate surgical techniques after CIRT. The increased PD-L1 expression supports the immunogenic effects of particle therapy and lays the groundwork for future studies. To enhance the therapeutic ratio of CIRT treatments, integrating dose-averaged LETd (LETd-based objectives into the plan optimization process should be considered., Trial Registration Number: ClinicalTrials.gov Identifier: NCT03822936., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Influenza A virus (IAV) infection is a major health risk during pregnancy. Whilst vaccination and antiviral agents are widely employed and reduce IAV-induced symptoms, they are not sufficient to control IAV infections in pregnancy, especially during pandemics. Respiratory viruses like IAV, exploit immune alterations that occur during pregnancy, including the upregulation of immune checkpoint proteins (ICPs) like PDL1, PD1 and CTLA4. We hypothesize that blocking expression of PDL1 on innate immune cells will improve maternal immunity following IAV infection. We utilized murine models of IAV infection during pregnancy with and without treatment with the immune checkpoint inhibitor (ICI), a-PDL1. Pregnant and non-pregnant mice were infected with mouse adapted IAV (A/PR/8) and assessed at 3 days post infection (3dpi). Lung cells were analyzed using flow cytometry. Lung mRNA expression of inflammatory and antiviral markers and histology was measured. Protein concentrations of inflammatory and antiviral markers, as well as viral titers was measured from lung bronchiolar lavage fluid (BALF). Lung function was also assessed. Following IAV infection, immune cells from pregnant mice had significant increases in the ICPs, PDL1, PD1 and CTLA4. a-PDL1 treatment effectively suppressed these ICPs and increased the activation marker, CD86. A-PDL1 treatment also reduced lung inflammatory cell infiltration and viral titres, increased antiviral responses, and improved lung function. Overall, IAV infection in pregnancy activates key inhibitory ICPs, leading to worsened disease outcomes. a-PDL1 treatment during IAV infection in pregnancy is an effective method to reduce ICP expression and improve overall immune cell responses.

High-grade urothelial carcinoma either non- Schistosoma (NS-UBC) or Schistosoma (S-UBC)-associated is the tenth cause of death worldwide and represents a serious therapeutic problem. Evaluation of the immmunohistochemical expression of tumor necrosis factor-alpha (TNFα), epidermal growth factor receptor (EGFR), programmed cell death protein-1 (PDL1), estrogen receptor-alpha (ERα) and UroplakinIII, in the high-grade in NS-UBC and S-UBC as potential prognostic and therapeutic targets analyzed through estimation of area percentage, optical density and international pathological scoring system for each marker. Sixty high grade urothelial carcinoma cases were enrolled in the study (30 cases of NS-UBC and 30 cases of S-UBC). The cases were immunohistochemically-assessed for TNFα, EGFR, PDL1, ERα and Uroplakin III expression. In S-UBC, parasite load was also evaluated for correlation with the immunohistochemical markers' expression in S-UBC. The area percentage of immune-expression of TNFα and EGFR was higher in S-UBC compared to NS-UBC. On the other hand, the NS-UBC displayed statistically-higher expression of PDL1 and uroplakinIII (p-value <0.001). ERα revealed higher, yet, non-significant expressions in S-UBC compared to NS-UBC (p-value =0.459). PDL1 expression showed the most superior record regarding area percentage (64.6± 34.5). Regarding optical density, TNF-α showed the highest transmittance expression (2.4 ± 0.9). EGFR positively correlated with PDL1 in S-UBC (r= 0.578, p-value =0.001) whereas in NS-UBC, TNFα and PDL1 (r=0.382, p-value=0.037) had positive correlation. Schistosoma eggs in tissues oppose uroplakin III expression and trigger immunomodulation via PDL1. Due to lower UroplakinIII expression, S-UBC is supposed to have a poorer prognosis. Hormonal therapy is not hypothesized due to a very minimal ERα expression in both NS-UBC and S-UBC. Regarding immunotherapy, anti-TNF-α is suggested for S-UBC whilst in NS-UBC, blockading PDL1 might be useful. Targeted EGFR therapy seems to carry emphasized outcomes in S-UBC. Correlations encourage combined immune therapy in NS-UBC; nevertheless, in S-UBC, combined anti-EGFR and PDL1 seem to be of benefit. • Uroplakin III showed minimal expression in S-UBC indicating poor prognosis. • The weak expression of ER does not support hormonal therapy in both S-UBC and NS-UBC. • Anti-TNF is recommended in S-UBC. • Blockage of the PD-1/PDL1 pathway is suggested be efficient in NS-UBC. [ABSTRACT FROM AUTHOR]

Background Aims: The immunomodulatory capacity of mesenchymal stem/stromal cells (MSCs) is a key feature that makes them particularly valuable for regenerative medicine. However, this potential is affected by the chronological aging of the donors and the cell expansion procedures in culture. We have demonstrated that GATA binding protein 6 (GATA6) plays a pivotal role in the aging of MSCs and inhibiting GATA6 rejuvenates the characteristics of MSCs., Methods: In this study, we compared the immunomodulatory capabilities of young and old MSC models, using induced pluripotent stem cells-derived rejuvenated MSCs (rMSCs) and their parental MSCs (pMSCs), respectively, to identify a key mechanism involved in the differential regulation of these capabilities. Additionally, we explored the role of GATA6 in mediating the mechanism., Results: Our results demonstrated that rMSCs exhibited downregulated aging-associated regulators, including p53, p21 and GATA6, and showed enhanced suppression of T cell proliferation compared to pMSCs. Through analyzing our previous RNA-seq data and employing target gene knockdown, we determined both suppressors of cytokine signaling 3 (SOCS3) and interleukin 6 were involved in GATA6-induced regulation, collectively affecting the expression of programmed death ligand 1 (PDL1) in both pMSCs and rMSCs., Conclusions: Our findings underline the significance of the GATA6/SOCS3/PDL1 pathway in regulating aging-associated changes in MSC immunomodulatory activity, providing valuable insights into the potential use of rMSCs in the treatment of immune diseases and regenerative medicine., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article., (Copyright © 2024 International Society for Cell & Gene Therapy. Published by Elsevier Inc. All rights reserved.)

It is difficult to obtain specific tumor antigens, which is one of the main obstacles in the development of tumor vaccines. The vaccines containing multivalent antigens are thought to be more effective in antitumor therapy. In this study, a mRNA encoding three neoantigens of melanoma were prepared and encapsulated into the mannosylated chitosan-modified ethosomes (Eths MC ) to obtain a multivalent mRNA vaccine (MmRV) for transcutaneous immunization (TCI). MmRV can effectively induce maturation of dendritic cells, with a better performance than mRNA of a single neoantigen. TCI patches (TCIPs) loading MmRV or siRNA against PDL1 (siPDL1) were prepared and applied to the skin of melanoma-bearing mice. The results showed that TCIPs significantly increase the levels of TNF-α, IFN-γ, and IL-12 in both plasma and tumor tissues, inhibit tumor growth, as well as promote infiltration of CD 4+ and CD 8+ T cells in the tumor tissues. Furthermore, the combination of MmRV and siPDL1 showed much better antitumor effects than either monotherapy, suggesting a synergistic effect between the vaccine and PDL1 blocker. In addition, the treatment with the TCIPs did not cause damage to the skin, blood, and vital organs of the mice, showing good biosafety. To the best of our knowledge, this work is the first to construct a noninvasive TCI system containing MmRV and siPDL1, providing a convenient and promising approach for tumor treatment.

• 2 patients treated with ICIs achieved major responses at 4 irradiated sites. • Responses lasted for 5–24 months. • Two radiation modalities were used: electron-beam and photon-beam radiotherapies. • These cases highlight the potentially powerful synergistic effect of RT and ICIs. The immuno-modulatory effects of ionizing radiation are well-known and preclinical studies suggest a synergistic effect of combining radiotherapy (RT) and IO. However, data regarding the clinical activity and safety of this approach are limited. We present the cases of two patients with SCCHN primary progressing to PDL1-based IO within a clinical trial (NCT03383094), that received subsequent but not concurrent palliative RT using two different modalities (electron beam and photon beam therapies). Both patients achieved major and durable responses at 4 irradiated sites, with excellent tolerance and no grade ≥ 3 toxicities. Complete response occurred in 3 of the disease areas (all locoregional) and partial response in 1 metastatic lesion. Palliative radiotherapy after progression to IO was safe and demonstrated profound and durable responses in the cases presented. [ABSTRACT FROM AUTHOR]

To explore immune cell infiltration and PDL1 expression in the tumor microenvironment (TME) of primary central nervous system lymphoma (PCNSL), we performed immunohistochemical staining on paraffin-embedded tumor tissues from 34 patients diagnosed with PCNSL. CD8 and CD163 positive cells were manually counted, and PDL1 expression was quantified by the H-score scoring method in the tumor center and around the tumor. The Kaplan-Meier method was used to analyze the prognostic value of the TME. We found obvious infiltration of CD8 + CTLs and CD163 + TAMs in the TME of PCNSL patients. And PDL1 was expressed in the tumor center as well as around the tumor. Survival analysis showed that high CD8 + CTLs levels and high intratumoral PDL1 expression were significantly correlated with longer OS. High CD8 + CTLs and CD163 + TAMs levels were associated with longer PFS.

Targeting immune inhibitory checkpoint (IC) pathways have attracted great attention as a promising strategy for treating gastrointestinal (GI) cancer. However, the therapeutic efficacy is low in most cases, and little progress has been made in establishing biomarkers that predict the possible responses, and combination regimens that enhance the therapeutic efficacy. As a predictive biomarker, soluble forms of IC molecules have been recently highlighted. However, little is known about which IC molecules is most critically associated with the treatment resistance, and also about the biological and immunological roles of the IC molecules in GI cancer. In this study, we analyzed sera obtained from advanced gastric cancer patients before and one month after treatment with anti-PD1 nivolumab for soluble IC molecules by ELISA. We found that decrease of soluble CTLA4 (sCTLA4) at posttreatment were significantly associated with a better prognosis, and combination with low level of CRP at posttreatment more clearly defined anti-PD1 responders with long-term survival. Indeed, in the in vitro setting, CRP stimulation upregulated CTLA4 expression in tumor cells followed by generation of sCTLA4 that suppressed CTL induction, and simultaneously conferred high self-renewal and invasive abilities on the tumor cells accompanied by increase of EMT-related gene expressions. In the in vivo setting, CRP injection elevated sCTLA4 level in sera of mouse tumor metastasis models, leading to failure of anti-PD1 therapy. However, treatment with anti-CTLA4 mAb or a PPARγ agonist that can reduce in vivo CRP successfully elicited anti-tumor efficacy in the anti-PD1 resistant models. These suggest that targeting CRP and sCTLA4 may be a promising strategy for improving clinical outcomes in the treatments, including anti-PD1 therapy, of GI cancer., Competing Interests: H.S. has received honoraria from Ono Pharmaceutical, Bristol-Myers Squibb and Taiho Pharmaceutical, and research funds from Ono Pharmaceutical, Taiho Pharmaceutical, MSD, Astellas and Amgen. N.B. has received honoraria from Ono Pharmaceutical, Taiho Pharmaceutical and Lilly, and research funds from Ono pharmaceutical and Takeda pharmaceutical. A.T. has received honoraria from Lilly, Taiho Pharmaceutical, Ono Pharmaceutical, Chugai Pharmaceutical, Takeda Pharmaceutical and Merck Serono, and research funds from Ono Pharmaceutical, Takeda Pharmaceutical, Merck Sharp & Dohme, Eisai, Bayer and Bristol-Myers Squibb. K.K. has received consulting fees from Bristol-Myers Squibb, MSD, Beigene, Roche, AstraZeneca and Bayer, honoraria from Ono pharmaceutical, Bristol-Myers Squibb and Taiho pharmaceutical, and research funds from Ono pharmaceutical, Bristol-Myers Squibb, MSD, Beigene, Chugai Pharmaceutical, Shionogi, AstraZeneca and Bayer., (AJCR Copyright © 2024.)

Purpose Triple-negative breast cancer (TNBC) has a poor outcome compared to other subtypes. Immune checkpoint inhibitors (ICIs) have changed the treatment paradigm in metastatic diseases as well as in neoadjuvant setting. The response to these agents is affected by programmed death ligand 1 (PDL1) receptor expression which are reported objectively as a score. PDL1 is a prognostic marker also. Here, we present clinicopathological characteristics of metastatic TNBCs, report the proportion of PDL1 expression and its association with clinicopathological factors as well as survival. Methods This is a prospective study carried out at a tertiary cancer care centre in South India. Case records of all breast cancer patients treated in two years between August 2021 and July 2023 were reviewed, patients with metastatic TNBC were selected. Patient's characteristics, histological features, molecular profile, and treatment were analyzed. PDL1 testing was carried out on pretreatment tumor tissue sections with immunohistochemistry (IHC) (Dako 22C3). PDL1 staining was interpreted as negative or positive based on combined positive score (CPS), with an expression less than 10 considered negative. Results A total of 118 patients were analyzed. With a median age of 46 years (36-65 years), 52.5% (62/118) were premenopausal. Family history of Ca Breast was seen in 22% (26/118) patients. A majority of patients had left-sided tumor 55.9% (66/118). Visceral metastasis was more common 96.6% (82/118) than skeletal. Radical intent of treatment was adopted in 10% as patients had oligometastatic disease at presentation. As front-line treatment, anthracycline-based chemotherapy was administered to the majority 54.2% (64/118). The PDL1 expression with CPS more or equal to 10 was seen in 32.2% (38/118) patients. Survival was associated with menopausal status (p value=0.000) and family history (p value=0.028) but not with PDL1 nor sidedness in our study. Estimated survival at 12 months in PDL1 negative case is 10 ± 0.29 months, while in PDL1 positive case it is slightly more at 10 ± 0.75 months, but difference was not found to be statistically significant (p value=0.15). Conclusion TNBCs are highly aggressive subtype with limited treatment options and poorer outcomes. Our study shows PDL1 expression in 31.66% of the cases similar to other literature from India. Survival is associated with menopausal status and family history. No association was found between survival and PDL1 as well sidedness in our study., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Babu et al.)

• NitraTh helps CD47 break immune tolerance. • CD47-NitraTh seems an optimal substitute for anti-CD47 antibodies with better efficacy with less side-effect. • Combination vaccination with PDL1–NitraTh further improves therapeutic outcome of CD47-NitraTh, by activating both innate and adaptive immune response. • NitraTh based vaccines reverses immunosuppressed tumor microenvironment by activating chemokine signaling pathway. Despite the clinical breakthrough made by immune checkpoint blockades (ICB) in cancer immunotherapy, immunosuppressed tumor microenvironment (TME) remains a major impediment in the efficacy of ICB immunotherapy. In this study, we constructed a Nitrated T cell epitope (NitraTh) linked vaccine targeting CD47, namely CD47-NitraTh. CD47-NitraTh could repress the progression of tumor by inducing tumor-specific immune response. Furthermore, combination vaccination with CD47-NitraTh and PDL1-NitraTh could reconstruct tumor associated macrophage, enhance macrophage-mediated phagocytosis for tumor cells, and promote the activation of tumor infiltrating T cells. Notably, by activating chemokine signaling pathway, NitraTh based vaccines reversed immunosuppressed TME, resulting in improved therapeutic outcome for tumor. With the advantage of reversing immunosuppressed TME, NitraTh based vaccine seems an optimal immunotherapy strategy for patients who are not sensitive to antibody based ICB. [ABSTRACT FROM AUTHOR]

Severe preeclampsia (sPE) is a systemic syndrome that may originate from chronic inflammation. Maintaining maternal-fetal hemostasis by the co-inhibitory molecule programmed death ligand 1 (PDL1) can be favorable for ameliorating inflammation from immune cells. Apart from programmed death 1 (PD1) expression, decidual macrophages (dMs) produce inflammatory cytokines, in response to cells which express PDL1. However, strong evidence is lacking regarding whether the PDL1/PD1 interaction between trophoblasts and decidual macrophages affects inflammation during sPE development. To determine whether the trophoblast-macrophage crosstalk via the PDL1/PD1 axis modulates the inflammatory response in sPE-like conditions, at first, maternal-fetal tissues from sPE and normal patients were collected, and the PDL1/PD1 distribution was analyzed by Western blot, immunohistochemistry/ immunofluorescence and flow cytometry. Next, a coculture system was established and flow cytometry was used to identify how PDL1 was involved in macrophage-related inflammation under hypoxic stress. Transcriptional analysis was performed to clarify the inflammation-associated pathway induced by the PDL1/PD1 interaction. Finally, the Nω-nitro-L-arginine methyl ester hydrochloride (L-NAME) mouse model was used to examine the effect of PDL1 on macrophage-related inflammation by measuring PE-like symptoms. In maternal-fetal tissue from sPE patients, placental extravillous trophoblasts (EVTs) and dMs had a surprisingly increase of PDL1 and PD1 expression, respectively, accompanied by a higher percentage of CD68 +CD86 + dMs. In vitro experiments showed that trophoblast-derived PDL1 under hypoxia interacted with PD1 on CD14 +CD80 +macrophages, leading to suppression of inflammation through the TNFα-p38/NFκB pathway. Accordingly, the PE-like mouse model showed a reversal of PE-like symptoms and a reduced F4/80 + CD86 + macrophage percentage in the uterus in response to recombinant PDL1 protein administration, indicating the protective effect of PDL1. Our results initially explained an immunological adaptation of trophoblasts under placental hypoxia, although this protection was insufficient. Our findings suggest the possible capacity of modulating PDL1 expression as a potential therapeutic strategy to target the inflammatory response in sPE. • EVT-derived PDL1 elevated in hypoxia stressful trophoblasts as adaptation. • PDL1/PD1 interaction protected placental chronic inflammation through TNFα-NFκB/p38 pathway. • The deficient compensation of PDL1 maybe an immunology etiology for PE. • PDL1 could be developed as a potential clinical target for PE treatment. [ABSTRACT FROM AUTHOR]