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Leukemia stem cells (LSCs) are widely believed to reside in well-characterized bone marrow (BM) niches; however, the capacity of the BM niches to accommodate LSCs is insufficient, and a significant proportion of LSCs are instead maintained in regions outside the BM. The molecular basis for this niche-independent behavior of LSCs remains elusive. Here, we show that integrin-α9 overexpression (ITGA9 OE) plays a pivotal role in the extramedullary maintenance of LSCs by molecularly mimicking the niche-interacting status, through the binding with its soluble ligand, osteopontin (OPN). Retroviral insertional mutagenesis conducted on leukemia-prone Runx-deficient mice identified Itga9 OE as a novel leukemogenic event. Itga9 OE activates Akt and p38MAPK signaling pathways. The elevated Myc expression subsequently enhances ribosomal biogenesis to overcome the cell integrity defect caused by the preexisting Runx alteration. The Itga9-Myc axis, originally discovered in mice, was further confirmed in multiple human acute myeloid leukemia (AML) subtypes, other than RUNX leukemias. In addition, ITGA9 was shown to be a functional LSC marker of the best prognostic value among 14 known LSC markers tested. Notably, the binding of ITGA9 with soluble OPN, a known negative regulator against HSC activation, induced LSC dormancy, while the disruption of ITGA9-soluble OPN interaction caused rapid cell propagation. These findings suggest that the ITGA9 OE increases both actively proliferating leukemia cells and dormant LSCs in a well-balanced manner, thereby maintaining LSCs. The ITGA9 OE would serve as a novel therapeutic target in AML., 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 paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Autophagy is an intracellular degradation process that sequesters cytoplasmic components in double-membrane vesicles known as autophagosomes, which are degraded upon fusion with lysosomes. This pathway maintains the integrity of proteins and organelles while providing energy and nutrients to cells, particularly under nutrient deprivation. Deregulation of autophagy can cause genomic instability, low protein quality, and DNA damage, all of which can contribute to cancer. Autophagy can also be overactivated in cancer cells to aid in cancer cell survival and drug resistance. Emerging evidence indicates that autophagy has functions beyond cargo degradation, including roles in tumor immunity and cancer stem cell survival. Additionally, autophagy can also influence the tumor microenvironment. This feature warrants further investigation of the role of autophagy in cancer, in which autophagy manipulation can improve cancer therapies, including cancer immunotherapy. This review discusses recent findings on the regulation of autophagy and its role in cancer therapy and drug resistance., 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 paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Glioblastoma is characterized by a pronounced resistance to therapy with dismal prognosis. Transcriptomics classify glioblastoma into proneural (PN), mesenchymal (MES) and classical (CL) subtypes that show differential resistance to targeted therapies. The aim of this study was to provide a viable approach for identifying combination therapies in glioblastoma subtypes. Proteomics and phosphoproteomics were performed on dasatinib inhibited glioblastoma stem cells (GSCs) and complemented by an shRNA loss-of-function screen to identify genes whose knockdown sensitizes GSCs to dasatinib. Proteomics and screen data were computationally integrated with transcriptomic data using the SamNet 2.0 algorithm for network flow learning to reveal potential combination therapies in PN GSCs. In vitro viability assays and tumor spheroid models were used to verify the synergy of identified therapy. Further in vitro and TCGA RNA-Seq data analyses were utilized to provide a mechanistic explanation of these effects. Integration of data revealed the cell cycle protein WEE1 as a potential combination therapy target for PN GSCs. Validation experiments showed a robust synergistic effect through combination of dasatinib and the WEE1 inhibitor, MK-1775, in PN GSCs. Combined inhibition using dasatinib and MK-1775 propagated DNA damage in PN GCSs, with GCSs showing a differential subtype-driven pattern of expression of cell cycle genes in TCGA RNA-Seq data. The integration of proteomics, loss-of-function screens and transcriptomics confirmed WEE1 as a target for combination with dasatinib against PN GSCs. Utilizing this integrative approach could be of interest for studying resistance mechanisms and revealing combination therapy targets in further tumor entities., 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 paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Plasticity, a key hallmark of cancer, enables cells to transition into different states, driving tumor heterogeneity. This cellular plasticity is associated with cancer progression, treatment resistance, and relapse. Cancer stem cells (CSCs) play a central role in this process, yet the molecular factors underlying cancer cell stemness remain poorly understood. In this study, we explored the role of XIST (X-inactive specific transcript) long noncoding RNA in ovarian cancer stemness and plasticity through in silico and in vitro analyses. We found that XIST is significantly down-regulated in ovarian tumors, with low XIST expression linked to a higher stemness index and lower overall survival. Knocking down XIST in ovarian cancer cells enhanced stemness, particularly increasing mesenchymal-like CSCs, and under hypoxic conditions, it promoted epithelial-like CSC markers. Our findings suggest that XIST loss leads to CSC enrichment and cellular plasticity in ovarian cancer, pointing to potential therapeutic targets for patients with low XIST expression., Competing Interests: Competing interests statement:The authors declare no competing interest.

Triple-negative breast cancer is a heterogeneous disease with high recurrence and mortality, linked to cancer stem cells (CSCs). Our study characterized distinct cell subpopulations and signaling pathways to explore chemoresistance. We observed cellular heterogeneity among and within the cells regarding phenotyping and drug response. In untreated BT-549 cells, we noted plasticity properties in both CD44 + /CD24 + /CD146 + hybrid cells and CD44 - /CD24 + /CD146 + epithelial cells, enabling phenotypic conversion into CD44 + /CD24 - /CD146 - epithelial-mesenchymal transition (EMT)-like like breast CSCs (BCSCs). Additionally, non-BCSCs may give rise to ALDH + epithelial-like BCSCs. Enriched BCSCs demonstrated the potential to differentiation into CD44 - /CD24 - /CD146 - cells and exhibited self-renewal capabilities. Similar phenotypic plasticity was not observed in untreated Hs 578T and HMT-3522 S1 cells. BT-549 cells were more resistant to paclitaxel/PTX than to doxorubicin/DOX, a phenomenon potentially linked to the presence of CD24 + cells prior to treatment. Under the CSCs-enriched spheroids model, BT-549 demonstrated extreme resistance to DOX, likely due to the enrichment of BCSCs CD44 + /CD24 - /CD146 - and the tumor cells CD44 - /CD24 - /CD146 - . Additionally, DOX treatment induced the enrichment of plastic and chemoresistant cells, further exacerbating resistance mechanisms. BT-549 exhibited high heterogeneity, leading to significant alterations in cell subpopulations under BCSCs enrichment, demonstrating increased phenotypic plasticity during EMT. This phenomenon appears to play a major role in DOX resistance, as indicated by the presence of the refractory cells CD44 + /CD24 - /CD146 - BCSCs EMT-like, CD44 - /CD24 - /CD146 - tumor cells, and elevated STAT3 expression. Gene expression data from BT-549 CSCs-enriched spheroids suggests that ferroptosis may be occurring via autophagic regulation triggered by RAB7A, highlighting this gene as a potential therapeutic target., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Milene Pereira Moreira has patent #BR 10 2022 011155 3 pending to no. Luciana Maria Silva has patent #BR 10 2022 011155 3 pending to no. Eliza Pereira Franco has patent #BR 10 2022 011155 3 pending to no. Leticia da Conceicao Braga has patent #BR 10 2022 011155 3 pending to no. Geovanni Dantas Cassali has patent #BR 10 2022 011155 3 pending to No. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Liver cancer stem cells (LCSCs) are thought to drive the metastasis and recurrence, however, the heterogeneity of molecular markers of LCSCs has hindered the development of effective methods to isolate them., Methods: This study introduced an effective approach to isolate and culture LCSCs from human primary liver cancer (HPLC), leveraging mouse embryonic fibroblasts (MEFs) as feeder cells in conjunction with using defined medium. Isolated LCSCs were further characterized by multiple approaches. Transcriptome sequencing data analysis was conducted to identify highly expressed genes in LCSCs and classify different subtypes of liver cancers., Results: Total sixteen cell strains were directly isolated from 24 tissues of three types of HPLC without sorting, seven of which could be maintained long-term culture as colony growth on MEFs, which is unique characteristics of stem cells. Even 10 of cloned cells formed the tumors in immunodeficient mice, indicating that those cloned cells were tumorgenic. The histologies and gene expression pattern of human xenografts were very similar to those of HPLC where these cloned cells were isolated. Moreover, putative markers of LCSCs were further verified to all express in cloned cells, confirming that these cells were LCSCs. These cloned LCSCs could be cryopreserved, and still maintained the feature of colony growth on MEFs after the recovery. Compared to suspension culture as conventional approach to culture LCSCs, our approach much better maintained stemness of LCSCs for a long time. To date, these cloned cells could be cultured on MEFs over 12 passages. Moreover, bioinformatics analysis of sequencing data revealed the gene expression profiles in LCSCs, and liver cancers were classified into two subtypes C1 and C2 based on genes associated with the prognosis of LCSCs. Patients of the C2 subtype, which is closely related to the extracellular matrix, were found to be sensitive to treatments such as Cisplatin, Axitinib, JAK1 inhibitors, WNT-c59, Sorafenib, and RO-3306., Conclusion: In summary, this effective approach offers new insights into the molecular landscape of human liver cancers, and the identification of the C2 subtype and its unique response to the treatment pave the way for the creation of more effective, personalized therapeutic strategies., Competing Interests: Statement Ethics approval and consent to participate Human liver tissues used in this study was approved by Ethics Committee of Guangzhou First People’s Hospital (Approval Number: K-2019-167-02). All animal experiments were approved by Ethics Committee of South China University of Technology (SCUT) (Approval Number: 2019073) for the Use and Care of Laboratory Animals. Competing interests The authors declare that they have no competing interests., (© 2024. The Author(s).)

Background: Polyploid giant cancer cells (PGCCs) have properties of cancer stem cells (CSCs). PGCCs with daughter cells (PDCs) undergo epithelial-mesenchymal transition and show enhanced cellular plasticity. This study aimed to elucidate the mechanisms underlying the osteo/chondrogenic-like differentiation of PDCs, which may be exploited therapeutically by transdifferentiation into post-mitotic and functional cells., Methods: Cobalt chloride was used to induce PGCC formation in MDA-MB-231 and HEY cells, and PDCs were cultured in osteo/chondrogenic differentiation media. Alcian blue staining was used to confirm osteo/chondrogenic differentiation, and the cell cycle was detected using flow cytometry. The expression of osteo/chondrogenic differentiation-related proteins was compared, and a co-immunoprecipitation assay was used to demonstrate the interactions between proteins. Bioinformatic analysis was used to explore the regulatory mechanism of osteo/chondrogenic differentiation, and a dual-luciferase reporter assay was performed to validate the interaction between transcriptional factors and target genes. Animal xenograft models were used to confirm the osteo/chondrogenic differentiation of PDCs., Results: When cultured in osteo/chondrogenic medium, the stemness of PDCs decreased, and the expression of osteo/chondrogenic-related markers increased. This osteo/chondrogenic-like process was regulated by the transforming growth factor-β pathway in a time-dependent manner. A concurrent increase in the expression of histone acetyltransferase p300 and the transcription factor CCCTC-binding factor (CTCF) was observed. Co-immunoprecipitation assays revealed that p300 acetylated the osteo/chondrogenic marker RUNT-related transcription factor 2 (RUNX2). Analysis of chromatin immunoprecipitation sequencing datasets revealed that both CTCF and histone H3 lysine 27 acetylation (H3K27ac) were enriched in the promoter region of E1A-associated protein p300 (P300). The four predicted binding sites for CTCF and P300 were validated using dual-luciferase reporter assays. We examined the interaction between CTCF and H3K27ac and found that these two proteins had a combined effect on the transactivation of P300., Conclusion: CTCF, in synergy with H3K27ac, amplified the expression of P300, facilitating acetyl group transfer to RUNX2. This acetylation stabilized RUNX2 and promoted osteo/chondrogenic differentiation, thereby reducing the incidence of PDC malignancies., Competing Interests: Declarations Ethical approval The experimental protocol was established according to the ethical guidelines of the Declaration of Helsinki and was approved by the Medicine Ethics Committee of the Tianjin Union Medical Center. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Glioblastoma (GBM), an aggressive brain malignancy with a cellular hierarchy dominated by GBM stem cells (GSCs), evades antitumor immunity through mechanisms that remain incompletely understood. Like most cancers, GBMs undergo metabolic reprogramming toward glycolysis to generate lactate. Here, we show that lactate production by patient-derived GSCs and microglia/macrophages induces tumor cell epigenetic reprogramming through histone lactylation, an activating modification that leads to immunosuppressive transcriptional programs and suppression of phagocytosis via transcriptional upregulation of CD47, a "don't eat me" signal, in GBM cells. Leveraging these findings, pharmacologic targeting of lactate production augments efficacy of anti-CD47 therapy. Mechanistically, lactylated histone interacts with the heterochromatin component chromobox protein homolog 3 (CBX3). Although CBX3 does not possess direct lactyltransferase activity, CBX3 binds histone acetyltransferase (HAT) EP300 to induce increased EP300 substrate specificity toward lactyl-CoA and a transcriptional shift toward an immunosuppressive cytokine profile. Targeting CBX3 inhibits tumor growth by both tumor cell-intrinsic mechanisms and increased tumor cell phagocytosis. Collectively, these results suggest that lactate mediates metabolism-induced epigenetic reprogramming in GBM that contributes to CD47-dependent immune evasion, which can be leveraged to augment efficacy of immuno-oncology therapies.

Ovarian cancer (OC) is a devastating disease for women, with chemotherapy resistance taking the lead. Cisplatin has been the first-line therapy for OC for a long time. However, the resistance of OC to cisplatin is an important impediment to its efficacy. Mounting studies showed that ovarian cancer stem cells (OCSCs) affected chemotherapy resistance by secreting exosomes. MicroRNAs (miRNAs) play important roles in exosomes secreted by OCSCs. Here, through the analysis of GEO database (GSE107155) combined with RT-qPCR of OC-related cells/clinical tissues, it was found that hsa-miR-4516 (miR-4516) was significantly up-regulated in OCSCs. Then, OCSCs-derived exosomes were isolated and identified, and it was observed the influence of exosomes on the chemoresistance in SKOV3/cisplatin (SKOV3/DDP) cells. These results manifested that OCSCs-mediated exosomes facilitated the chemoresistance of SKOV3/DDP cells by delivering miR-4516 into them. Growth arrest-specific 7 (GAS7), a downstream target of miR-4516, was determined by bioinformatics prediction combined with molecular biological detection. Next, we up-regulated GAS7 expression and discovered that the promotion of chemoresistance in SKOV3/DDP cells by OCSCs-derived exosomes was significantly impaired. Finally, the mice tumor model of SKOV3/DDP cells was built to estimate the effect of GAS7 over-expression on OC growth. The results showed that GAS7 inhibited the chemoresistance of OC in vivo. In conclusion, our experiments suggested that OCSCs-derived exosomes enhanced OC cisplatin resistance by suppressing GAS7 through the delivery of miR-4516. This study provides a possible target for the treatment of OC DDP resistance., 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 paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Cancer stem cells (CSCs) play a significant role in the recurrence and drug resistance of esophageal carcinoma (ESCA). Ferroptosis is a promising anticancer therapeutic strategy that effectively targets CSCs exhibiting high tumorigenicity and treatment resistance. However, there is a lack of research on the combined role of ferroptosis-related genes (FRGs) and stemness signature in the prognosis of ESCA., Methods: The cellular compositions were characterized using single-cell RNA sequencing (scRNA-seq) data from 18 untreated ESCA samples. 50 ferroptosis-related stemness genes (FRSGs) were identified by integrating FRGs with stemness-related genes (SRGs), and then the cells were grouped by AUCell analysis. Next, functional enrichment, intercellular communication, and trajectory analyses were performed to characterize the different groups of cells. Subsequently, the stem-ferr-index was calculated using machine learning algorithms based on the expression profiles of the identified risk genes. Additionally, therapeutic drugs were predicted by analyzing the GDSC2 database. Finally, the expression and functional roles of the identified marker genes were validated through in vitro experiments., Results: The analysis of scRNA-seq data demonstrates the diversity and cellular heterogeneity of ESCA. Then, we identified 50 FRSGs and classified cells into high or low ferroptosis score stemness cells accordingly. Functional enrichment analysis conducted on the differentially up-regulated genes between these groups revealed predominant enrichment in pathways associated with intercellular communication and cell differentiation. Subsequently, we identified 9 risk genes and developed a prognostic signature, termed stem_ferr_index, based on these identified risk genes. We found that the stem-ferr-index was correlated with the clinical characteristics of patients, and patients with high stem-ferr-index had poor prognosis. Furthermore, we identified four drugs (Navitoclax, Foretinib, Axitinib, and Talazoparib) with potential efficacy targeting patients with a high stem_ferr_index. Additionally, we delineated two marker genes (STMN1 and SLC2A1). Particularly noteworthy, SLC2A1 exhibited elevated expression levels in ESCA tissues and cells. We provided evidence suggesting that SLC2A1 could influence the migration, invasion, and stemness of ESCA cells, and it was associated with sensitivity to Foretinib., Conclusion: This study constructed a novel ferroptosis-related stemness signature, identified two marker genes for ESCA, and provided valuable insights for developing more effective therapeutic targets targeting ESCA CSCs in the future., 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 paper., (Copyright © 2024. Published by Elsevier B.V.)

Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance particularly of mesenchymal glioblastoma stem-like cells (GSCs) has been proposed to contribute to therapy failure. Recently, we have shown that a mesenchymal-to-proneural mRNA signature of patient derived GSC-enriched (pGSC) cultures associates with in vitro radioresistance and gel invasion. Importantly, this pGSC mRNA signature is prognostic for patients' tumor recurrence pattern and overall survival. Two mesenchymal markers of the mRNA signature encode for IK Ca and BK Ca Ca 2+ -activated K + channels. Therefore, we analyzed here the effect of IK Ca - and BK Ca -targeting concomitant to (fractionated) irradiation on radioresistance and glioblastoma spreading in pGSC cultures and in pGSC-derived orthotopic xenograft glioma mouse models. To this end, in vitro gel invasion, clonogenic survival, in vitro and in vivo residual DNA double strand breaks (DSBs), tumor growth, and brain invasion were assessed in the dependence on tumor irradiation and K + channel targeting. As a result, the IK Ca - and BK Ca -blocker TRAM-34 and paxilline, respectively, increased number of residual DSBs and (numerically) decreased clonogenic survival in some but not in all IK Ca - and BK Ca -expressing pGSC cultures, respectively. In addition, BK Ca - but not IK Ca -blockade slowed-down gel invasion in vitro. Moreover, systemic administration of TRAM-34 or paxilline concomitant to fractionated tumor irradiation increased in the xenograft model(s) residual number of DSBs and attenuated glioblastoma brain invasion and (numerically) tumor growth. We conclude, that K Ca -blockade concomitant to fractionated radiotherapy might be a promising new strategy in glioblastoma therapy., (© 2024 The Author(s). International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Background: Neoadjuvant therapy with trastuzumab, pertuzumab and paclitaxel (THP) has significantly improved the prognosis of patients with human epidermal growth factor receptor 2 (HER2) + breast cancer (BC). However, there remains a subset of non-responsive patients. Thus, this study sought to identify key regulators of THP neoadjuvant therapy resistance and potential targets to sensitize sensitivity., Methods: The Cancer Genome Atlas database, Gene Expression Omnibus and membrane protein database were used to identify the key regulator of THP neoadjuvant resistance. The biological functions and mechanisms of delta-like 4 proteins (DLL4) in THP therapy resistance were investigated in vitro and in vivo using the bioinformatic analysis, multiplex immunofluorescence, flow cytometry, sphere formation assays and chromatin immunoprecipitation, etc. Furthermore, DLL4-targeted chimeric antigen receptor (CAR)-T cells were established to sensitize THP therapy., Results: DLL4 was identified as a key target in THP neoadjuvant therapy resistance for HER2 + BC. Mechanistically, DLL4 + tumor cells exhibited enhanced stemness and resistance to the THP neoadjuvant chemotherapy. Additionally, soluble DLL4 can split away from tumor cells and diffuse into the stroma, where it can activate the Notch signaling pathway in neutrophils, inducing the formation and release of neutrophil extracellular traps (NETs) by regulating the transcription of MPO, PDIA4 and ELANE. This led to the exclusion of lymphocyte infiltration, thereby enhancing therapy resistance. What is more, we designed a DLL4-targeted CAR-T to eliminate DLL4 + tumor cells and reverse the resistant status., Conclusions: Our study revealed novel functions of DLL4 in cell stemness and immune infiltration, including NET formation and T cell exclusion, which collectively contributed to THP neoadjuvant therapy resistance in HER2 + BC. Furthermore, we provided a CAR-T-based therapy to sensitize the THP neoadjuvant therapy., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Pseudomyxoma peritonei (PMP) is a rare malignant peritoneal tumor that readily recurs and metastasizes. Studies have shown that cancer stem cells (CSCs) play an important role in tumor recurrence, metastasis, and prognosis., Objective: In this study, our aim was to isolate CSCs from various tissues of PMP patients and compare their proliferation, migration, and anti-inflammatory abilities., Methods: We identified CSCs subsets with markers CD133 + , CD166 + , and CD133 + /CD166 + at the gene level using single-cell mRNA sequencing (scRNA-seq). Appendiceal CSCs (AC), peritoneal CSCs (PC), and mucous CSCs (MC) were obtained using MACSQuant Tyto sorting technology and FlowSight imaging flow cytometry. The cells were cultured and markers were identified. Finally, the functional phenotypes of the three cell types were compared., Results: CSCs content was highest in the appendiceal tumor tissue and lowest in the mucous tissue. The cell viability rate of the sorted CSCs was above 98%, and the positive rate of CD133 + and CD166 + was 70-80%, and CD133 + /CD166 + was about 30%. Among the three types of CSCs, MC had the highest proliferation ability, and TNF-α has the greatest inhibitory effect on AC migration., Conclusion: AC in patients was more inert and anti-inflammatory, whereas abdominal cavity MC and PC were more active. This study revealed the biological characteristics of CSCs in different tumor tissues of patients with PMP, providing a reference for future targeted CSCs therapy., Competing Interests: Declarations Ethics approval and consent to participate All human tissues were handled in accordance with protocols approved by the hospital’s Ethics Committee (Application No. 2024-024). The patients or their guardians/legally authorized representatives/next of kin provided written informed consent for the use of samples. Consent for publication Not applicable. Competing interests The authors have no conflicts of interest to declare., (© 2024. The Author(s).)

Background: Laryngeal cancer (LCA) is one of the most common head and neck squamous cell carcinoma with poor outcome. LCA stem cells are the main reason for LCA therapy resistance and relapse. Understanding the molecular mechanisms of the self-renew of LCA stem cells is critical to develop now targets and strategies for LCA therapy., Methods: Q-PCR and western blotting assays were used to determine NID1 level in LCA tissues and normal laryngeal tissues. MTT, colony formation assay, apoptosis assay and animal model were used to investigate the effect of NID1 on radiotherapy resistance. Side population assay and sphere formation assay were used to determine the role of LCA in the self-renew of LCA stem cells., Results: NID1 was upregulated in LCA tissues, particularly in LCA tissues derived from relapsed patients, and associated with had poor outcome. NID1 knockdown suppressed radiotherapy resistance and the self-renew of LCA stem cells, while NID1 overexpression promoted radiotherapy resistance and the self-renew of LCA stem cells. Further analysis showed that NID1 promotes radiotherapy resistance and the self-renew of LCA stem cells via activating WNT pathway. Moreover, NID1 level was positively correlated with nuclear β-Catenin level in LCA tissues., Conclusion: Our results show that NID1 promotes radiotherapy resistance and the self-renew of LCA stem cells via activating WNT pathway, providing a novel potential target for LCA treatment., Competing Interests: Declarations Ethical approval All experimental procedures in studies involving animals were in accordance with the ethical standards of the Institutions at which the studies were conducted and were approved by Institutional Animal Care and Use Committee of Guangdong Provincial People’s Hospital.Prior patient consent and approval from the Institutional Research Ethics Committee of Guangdong Provincial People’s Hospital were obtained for the use of these clinical materials for research purposes. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Brain tumor stem cells (BTSCs) are a population of self-renewing malignant stem cells that play an important role in glioblastoma tumor hierarchy and contribute to tumor growth, therapeutic resistance, and tumor relapse. Thus, targeting of BTSCs within the bulk of tumors represents a crucial therapeutic strategy. Here, we report that edaravone is a potent drug that impairs BTSCs in glioblastoma. We show that edaravone inhibits the self-renewal and growth of BTSCs harboring a diverse range of oncogenic mutations without affecting non-oncogenic neural stem cells. Global gene expression analysis revealed that edaravone significantly alters BTSC transcriptome and attenuates the expression of a large panel of genes involved in cell cycle progression, stemness, and DNA repair mechanisms. Mechanistically, we discovered that edaravone directly targets Notchless homolog 1 (NLE1) and impairs Notch signaling pathway, alters the expression of stem cell markers, and sensitizes BTSC response to ionizing radiation (IR)-induced cell death. Importantly, we show that edaravone treatment in preclinical models delays glioblastoma tumorigenesis, sensitizes their response to IR, and prolongs the lifespan of animals. Our data suggest that repurposing of edaravone is a promising therapeutic strategy for patients with glioblastoma., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Neuroblastoma is the most common extra-cranial solid tumor diagnosed mostly in children below the age of five years and comprises of about 15 % of all paediatric cancer deaths. Tumor initiating cancer stem cells (CSCs) can be targeted for better treatment approaches. BASP1-AS1 is a long non coding (Lnc) RNA that is a divergent LncRNA for its coding gene brain abundant membrane attached signal protein 1 (BASP1). We had earlier demonstrated it to be expressed in foetus derived human neural progenitor cells (hNPCs), where it was a positive regulator of BASP1 and was critical for neural differentiation. In this study, we have investigated the role of BASP1-AS1 in CSCs derived from the human neuroblastoma cell line SH-SY5Y. We cultured SH-SY5Y cells on Poly-d-Lysine coated flasks in serum free media supplemented with growth factors, which led to the enrichment of CSCs as determined by marker expression. When grown on ultra-low attachment flasks, these cells formed CSCs enriched neurospheres. We examined the effects of BASP1-AS1 siRNA mediated knockdown on CSCs enriched SH-SY5Y cells and SH-SY5Y derived neurospheres. BASP1-AS1 knockdown decreased the levels of the corresponding gene BASP1 and the rate of cell proliferation of CSCs enriched cells along with low expression of Ki67. It also reduced the mRNA levels of stem cell and pluripotency gene markers (CD133, CD44, c-KIT, SOX2, OCT4 and NANOG), as also Wnt 2 and the Wnt pathway effector β catenin. It also abrogated the formation of neurospheres in ultra-low attachment flasks. A similar effect on proliferation and stemness related properties was seen on BASP1 knockdown. BASP1-AS1 and its related pathways may provide a point of intervention for the CSCs population in neuroblastoma., 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 paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Embryonal carcinoma (EC), characterized by a high degree of stemness similar to that of embryonic stem cells, is the most malignant subtype within non-seminomatous testicular germ cell tumors (TGCTs). However, the mechanisms underlying its malignancy remain unknown. In this study, we employed single-cell RNA sequencing to analyze four non-seminoma samples. Our differential expression analysis revealed high expression of SERPINB9 in metastatic EC cells. We conducted in vitro experiments to further investigate SERPINB9's role in the progression of EC. Functionally, the knockdown of SERPINB9 in NCCIT and NTERA-2 leads to a diminished migratory capability and decreased cis-platin resistance, as demonstrated by Transwell migration assay and drug sensitivity assay. Moreover, embryoid bodies showed reduced size and lower OCT4 expression, alongside heightened expression of differentiation markers AFP, ACTA2, and CD57 in shSERPINB9 cells. In vivo, the role of SERPINB9 in maintaining cancer stemness was validated by the limiting dilution assay. Mechanistically, Bulk RNA-seq further showed downregulation of ERK1/2 signaling and WNT signaling pathways with concomitant upregulation of differentiation pathways subsequent to SERPINB9 knockdown. Additionally, the analysis indicated increased levels of cytokines linked to tertiary lymphoid structures (TLS), such as IL6, IL11, IL15, CCL2, CCL5, and CXCL13 in shSERPINB9 cells, which were further validated by ELISA. Our research indicates that SERPINB9 plays a key role in driving tumor progression by enhancing tumor stemness and suppressing TLS. This study stands as the first to elucidate the molecular signature of non-seminomas at a single-cell level, presenting a wealth of promising targets with substantial potential for informing the development of future therapeutic interventions., Competing Interests: Competing interests The authors declare no competing interests. Ethics approval and consent to participate The study was conducted in accordance with the Declaration of Helsinki. Ethics approval for human participants was provided by the Ethics Committee of Shanghai Ninth People’s Hospital affiliated with Shanghai Jiao Tong University School of Medicine (approval number: SH9H-2019-T279-3) and the Research Ethics Committee of Shanghai Cancer Center, Fudan University (approval number: 050432-4-2108*). All animal experimental procedures were conducted in accordance with protocols approved by the Animal Care and Use Committee of Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine (approval number: SH9H-2019-A727-1). Informed consent was obtained from all subjects involved in the study. All methods were performed in accordance with the relevant guidelines and regulations., (© 2024. The Author(s).)

Background: MicroRNAs (miRNAs) are critical regulators of cancer progression, prompting our investigation into the specific function of miR-630 in pancreatic cancer stem cells (PCSCs). Analysis of miRNA and mRNA expression data in PCSCs revealed downregulation of miR-630 and upregulation of PRKCI, implying a potential role for miR-630 in PCSC function and tumorigenicity., Results: Functional assays confirmed that miR-630 directly targets PRKCI, leading to the suppression of the Hedgehog signaling pathway and consequent inhibition of PCSC self-renewal and tumorigenicity in murine models. This study unveiled the modulation of the PRKCI-Hedgehog signaling axis by miR-630, highlighting its promising therapeutic potential for pancreatic cancer (PC) treatment., Conclusions: MiR-630 emerges as a pivotal regulator in PCSC biology, opening up new avenues for targeted interventions in PC. The inhibitory effect of miR-630 on PCSC behavior underscores its potential as a valuable therapeutic target, offering insights into innovative treatment strategies for this challenging disease., Competing Interests: Declarations Ethics approval and consent to participate The study protocol was approved by the ethics committee of Jiangxi Cancer Hospital. The written informed consents were provided from all the patients. Mice were treated humanely, and all experiment procedures were permitted by the Institutional Animal Care and Use Committee of Jiangxi Cancer Hospital (Approval no. 2024ky110). Efforts have made to minimize the mice suffering. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Background: NAD(P)-dependent steroid dehydrogenase-like protein (NSDHL), which is involved in breast tumor growth and metastasis, has been implicated in the maintenance of cancer stem cells. However, its role in regulating breast cancer stem-like cells (BCSCs) remains unclear. We have previously reported the clinical significance of NSDHL in patients with estrogen receptor-positive (ER +) breast cancer. This study aimed to elucidate the molecular mechanisms by which NSDHL regulates the capacity of BCSCs in the ER + human breast cancer cell line, MCF-7., Methods: NSDHL knockdown suppressed tumor spheroid formation in MCF-7 human breast cancer cells grown on ultralow-attachment plates. RNA sequencing revealed that NSDHL knockdown induced widespread transcriptional changes in the MCF-7 spheroids. TGF-β signaling pathway was the most significantly enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway (fold change ≥ 2, P ≤ 0.05) identified in NSDHL-knockdown MCF-7 spheroids compared with the control. In orthotopic tumor models injected with NSDHL-knockdown MCF-7 spheroids, tumor initiation and growth were strongly suppressed compared with those in the control., Results: BCSC populations with CD44+/CD24- and CD49f+/EpCAM + phenotypes and high ALDH activity were decreased in NSDHL-knockdown MCF-7 spheroids and xenograft tumors relative to controls, along with decreased secretion of TGF-β1 and 3, phosphorylation of Smad2/3, and expression of SOX2. In RNA-sequencing data from The (TCGA) database, a positive correlation between the expression of NSDHL and SOX2 was found in luminal-type breast cancer specimens (n = 998). Our findings revealed that NSDHL plays an important role in maintaining the BCSC population and tumor-initiating capacity of ER-positive MCF-7 spheroids, suggesting that NSDHL is an attractive therapeutic target for eliminating BCSCs, thus preventing breast cancer initiation and progression., Conclusions: Our findings suggest that NSDHL regulates the BCSC/tumor-initiating cell population in MCF-7 spheroids and xenograft tumors., (© 2024. The Author(s).)

End-stage liver disease is marked by portal hypertension, systemic elevations in ammonia, and development of hepatocellular carcinoma (HCC). While these clinical consequences of cirrhosis are well described, it remains poorly understood whether hepatic insufficiency and the accompanying elevations in ammonia contribute to HCC carcinogenesis. Using preclinical models, we discovered that ammonia entered the cell through the transporter SLC4A11 and served as a nitrogen source for amino acid and nucleotide biosynthesis. Elevated ammonia promoted cancer stem cell properties in vitro and tumor initiation in vivo. Enhancing ammonia clearance reduced HCC stemness and tumor growth. In patients, elevations in serum ammonia were associated with an increased incidence of HCC. Taken together, this study forms the foundation for clinical investigations using ammonia-lowering agents as potential therapies to mitigate HCC incidence and aggressiveness.

Colorectal cancer (CRC) is a major global concern. Mesenchymal stem cell-derived exosomes (MSC-EXOs) have demonstrated efficacy as a therapeutic approach for colorectal cancer. However, the precise mechanism by which MSC-EXOs treat colorectal cancer remains unclear. Human umbilical cord (hUC)-MSC-EXOs were isolated and identified. Cell Counting Kit-8 (CCK-8), Transwell, and colony formation assays were used to assess the activity of CRC cells. Glucose consumption, lactic acid production, and extracellular acidification rate (ECAR) were measured to assess glycolytic activity. Cell stemness was assessed using a sphere-formation assay. Furthermore, MSC-exosomal microRNAs (miRNAs) in CRC tissues were analyzed using the EVmiRNA database, and aberrantly expressed miRNAs in CRC cells were obtained from the Gene Expression Omnibus (GEO) database. The binding relationship between miR-486-5p and the never in mitosis gene A-related kinase 2 (NEK2) was predicted using the Starbase database and validated through RNA binding protein immunoprecipitation (RIP) and dual luciferase assays. These results showed that hUC-MSC-EXOs inhibited the proliferation and metastasis of CRC cells. Moreover, glycolysis and stemness abilities of CRC cells also decreased after treatment with hUC-MSC-EXOs. miR-486-5p was found to be enriched in hUC-MSC-EXOs and significantly downregulated in CRC cells. miR-486-5p directly bound to NEK2. Overexpression of NEK2 reversed the inhibitory effect of miR-486-5p on CRC cell glycolysis and stemness. Our study highlights that hUC-MSC-EXO miR-486-5p inhibits glycolysis and cell stemness in CRC by targeting NEK2. This finding offers compelling evidence supporting the potential application of hUC-MSC-EXOs in the treatment of CRC., (© 2024. The Author(s).)

The advent of tyrosine kinase inhibitors (TKIs) as treatment of chronic myeloid leukemia (CML) is a paradigm in molecularly targeted cancer therapy. Nonetheless, TKI-insensitive leukemia stem cells (LSCs) persist in most patients even after years of treatment and are imperative for disease progression as well as recurrence during treatment-free remission (TFR). Here, we have generated high-resolution single-cell multiomics maps from CML patients at diagnosis, retrospectively stratified by BCR::ABL1 IS (%) following 12 months of TKI therapy. Simultaneous measurement of global gene expression profiles together with >40 surface markers from the same cells revealed that each patient harbored a unique composition of stem and progenitor cells at diagnosis. The patients with treatment failure after 12 months of therapy had a markedly higher abundance of molecularly defined primitive cells at diagnosis compared to the optimal responders. The multiomic feature landscape enabled visualization of the primitive fraction as a mixture of molecularly distinct BCR::ABL1 + LSCs and BCR::ABL1 - hematopoietic stem cells (HSCs) in variable ratio across patients, and guided their prospective isolation by a combination of CD26 and CD35 cell surface markers. We for the first time show that BCR::ABL1 + LSCs and BCR::ABL1 - HSCs can be distinctly separated as CD26 + CD35 - and CD26 - CD35 + , respectively. In addition, we found the ratio of LSC/HSC to be higher in patients with prospective treatment failure compared to optimal responders, at diagnosis as well as following 3 months of TKI therapy. Collectively, this data builds a framework for understanding therapy response and adapting treatment by devising strategies to extinguish or suppress TKI-insensitive LSCs., Competing Interests: RW, LG, FS, MS, SS, RT No competing interests declared, PD, GK Is a board member and has equity in Nygen Analytics AB, HH Received honoraria from Pfizer, Novartis, BMS, and Incyte, SM Received honoraria and research funding from BMS, research funding from Novartis, Janpix, and honoraria from Dren Bio, JR Received honoraria and research funding from Novartis and Bristol-Myers Squibb (BMS) and honoraria from Ariad, (© 2023, Warfvinge et al.)

Glioma stem cells have been recognized as key players in glioma recurrence and therapeutic resistance, presenting a promising target for novel treatments. However, the limited understanding of the role glioma stem cells play in the glioma hierarchy has drawn controversy and hindered research translation into therapies. Despite significant advances in our understanding of gene regulatory networks, the dynamics of these networks and their implications for glioma remain elusive. This study employs a systemic theoretical perspective to integrate experimental knowledge into a core endogenous network model for glioma, thereby elucidating its energy landscape through network dynamics computation. The model identifies two stable states corresponding to astrocytic-like and oligodendrocytic-like tumor cells, connected by a transition state with the feature of high stemness, which serves as one of the energy barriers between astrocytic-like and oligodendrocytic-like states, indicating the instability of glioma stem cells in vivo. We also obtained various stable states further supporting glioma's multicellular origins and uncovered a group of transition states that could potentially induce tumor heterogeneity and therapeutic resistance. This research proposes that the transition states linking both glioma stable states are central to glioma heterogeneity and therapy resistance. Our approach may contribute to the advancement of glioma therapy by offering a novel perspective on the complex landscape of glioma biology., (© 2024. The Author(s).)

Tumors reprogram their metabolism to generate complex neoplastic ecosystems. Here, we demonstrate that glioblastoma (GBM) stem cells (GSCs) display elevated activity of the malate-aspartate shuttle (MAS) and expression of malate dehydrogenase 2 (MDH2). Genetic and pharmacologic targeting of MDH2 attenuated GSC proliferation, self-renewal, and in vivo tumor growth, partially rescued by aspartate. Targeting MDH2 induced accumulation of alpha-ketoglutarate (αKG), a critical co-factor for dioxygenases, including the N6-methyladenosine (m6A) RNA demethylase AlkB homolog 5, RNA demethylase (ALKBH5). Forced expression of MDH2 increased m6A levels and inhibited ALKBH5 activity, both rescued by αKG supplementation. Reciprocally, targeting MDH2 reduced global m6A levels with platelet-derived growth factor receptor-β (PDGFRβ) as a regulated transcript. Pharmacological inhibition of MDH2 in GSCs augmented efficacy of dasatinib, an orally bioavailable multi-kinase inhibitor, including PDGFRβ. Collectively, stem-like tumor cells reprogram their metabolism to induce changes in their epitranscriptomes and reveal possible therapeutic paradigms., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Acquisition of prostate cancer stem cells (PCSCs) manifested during androgen ablation therapy (ABT) contributes to castration-resistant prostate cancer (CRPC). However, little is known about the specific metabolites critically orchestrating this process. Here, we show that IMPA1-derived inositol enriched in PCSCs is a key metabolite crucially maintaining PCSCs for CRPC progression and ABT resistance. Notably, conditional Impa1 knockout in the prostate abrogates the pool and properties of PCSCs to orchestrate CRPC progression and prolong the survival of TRAMP mice. IMPA1-derived inositol serves as a cofactor that directly binds to and activates IMPDH2, which synthesizes guanylate nucleotides for maintaining PCSCs with ARlow/- features leading to CRPC progression and ABT resistance. IMPA1/inositol/IMPDH2 axis is upregulated in human prostate cancer, and its overexpression predicts poor survival outcomes. Genetically and pharmacologically targeting the IMPA1/inositol/IMPDH2 axis abrogates CRPC and overcomes ABT resistance in various CRPC xenografts, patient-derived xenograft (PDX) tumor models, and TRAMP mouse models. Our study identifies IMPDH2 as an inositol sensor whose activation by inositol represents a key mechanism for maintaining PCSCs for CRPC and ABT resistance., (© 2024 Hsu et al.)

The Hippo-YAP1 pathway is an evolutionally conserved signaling cascade that controls organ size and tissue regeneration. Dysregulation of Hippo-YAP1 signaling promotes initiation and progression of several types of cancer, including gastric cancer. As the Hippo-YAP1 pathway regulates expression of thousands of genes, it is important to establish which target genes contribute to the oncogenic program driven by YAP1 to identify strategies to circumvent it. In this study, we identified a vital role of forkhead box protein 4 (FOXP4) in YAP1-driven gastric carcinogenesis by maintaining stemness and promoting peritoneal metastasis. Loss of FOXP4 impaired gastric cancer spheroid formation and reduced stemness marker expression, whereas FOXP4 upregulation potentiated cancer cell stemness. RNA sequencing analysis revealed SOX12 as a downstream target of FOXP4, and functional studies established that SOX12 supports stemness in YAP1-induced carcinogenesis. A small-molecule screen identified 42-(2-tetrazolyl) rapamycin as a FOXP4 inhibitor, and targeting FOXP4 suppressed gastric cancer tumor growth and enhanced the efficacy of 5-fluorouracil chemotherapy in vivo. Collectively, these findings revealed that FOXP4 upregulation by YAP1 in gastric cancer regulates stemness and tumorigenesis by upregulating SOX12. Targeting the YAP1-FOXP4-SOX12 axis represents a potential therapeutic strategy for gastric cancer. Significance: Hippo-YAP1 signaling maintains stemness in gastric cancer by upregulating FOXP4, identifying FOXP4 as a stemness biomarker and therapeutic target that could help improve patient outcomes., (©2024 The Authors; Published by the American Association for Cancer Research.)

The persistence of cancer stem cells (CSC) is believed to contribute to resistance to platinum-based chemotherapy and disease relapse in ovarian cancer, the fifth leading cause of cancer-related death among US women. HOXC transcript antisense RNA (HOTAIR) is a long, noncoding RNA (lncRNA) overexpressed in high-grade serous ovarian cancer and linked to chemoresistance. However, HOTAIR impacts chromatin dynamics in ovarian CSCs. Oncogenic lncRNA's contributions to drug-resistant disease are incompletely understood. Here, we generated HOTAIR knockout (KO) high-grade serous ovarian cancer cell lines using paired CRISPR guide RNA design to investigate the function of HOTAIR. We show the loss of HOTAIR function resensitized ovarian cancer cells to platinum treatment and decreased the population of ovarian CSCs. Furthermore, HOTAIR KO inhibited the development of stemness-related phenotypes, including spheroid formation ability and expression of key stemness-associated genes ALDH1A1, NOTCH3, SOX9, and PROM1. HOTAIR KO altered the cellular transcriptome and chromatin accessibility landscape of multiple oncogenic-associated genes and pathways, including the NF-kB pathway. HOTAIR functions as an oncogene by recruiting enhancer of zeste homolog 2 (EZH2) to catalyze H3K27 trimethylation to suppress downstream tumor suppressor genes, and it was of interest to inhibit both HOTAIR and EZH2. In vivo, combining a HOTAIR inhibitor with an EZH2 inhibitor and platinum chemotherapy decreased tumor formation and increased survival. These results suggest a key role for HOTAIR in ovarian CSCs and malignant potential. Targeting HOTAIR in combination with epigenetic therapies may represent a therapeutic strategy to ameliorate ovarian cancer progression and resistance to platinum-based chemotherapy., (©2024 American Association for Cancer Research.)

Glioblastoma (GBM) is the most aggressive type of brain tumor, characterized by poor outcome and limited therapeutic options. During tumor progression, GBM may undergo the process of vasculogenic mimicry (VM), consisting of the formation of vascular-like structures which further promote tumor aggressiveness and malignancy. The resulting resistance to anti-angiogenetic therapies urges the identification of new compounds targeting VM. Extracts of natural plants may represent potential therapeutic tools. Among these, components of Ruta graveolens water extract (RGWE) display a wide range of biological activities. To test the effect of RGWE on human GBM and rat glioma cell line VM, tube formation on a gelled matrix was monitored. Quantitative assessment of VM formation shows the clear-cut inhibitory activity of RGWE. Unlike rutin, one of the most abundant extract components, the whole RGWE strongly reduced the migration and invasion of GBM tumor cells. Moreover, RGWE induced cell death of GBM patient-derived cancer stem cells and impaired VM at sub-lethal doses. Overall, our data reveal a marked RGWE-dependent inhibition of GBM cell survival, migration, invasion, and VM formation. Thus, the clear-cut ability of RGWE to counteract GBM malignancy deserves attention, holding the promise to bring natural products to clinical use, thus uncovering new therapeutic opportunities.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related mortality, with tumour heterogeneity, fueled by cancer stem cells (CSCs), intricately linked to treatment resistance. Therefore, it is imperative to advance therapeutic strategies targeting CSCs in NSCLC. In this study, we utilized RNA sequencing to investigate metabolic pathway alterations in NSCLC CSCs and identified a crucial role of nitric oxide (NO) metabolism in governing CSC stemness, primarily through modulation of the Notch1 protein. Mechanistically, NO-induced S-nitrosylation of Notch1 facilitated its interaction with the deubiquitylase UCHL1, leading to increased Notch1 protein stability and enhanced CSC stemness. By inhibiting NO synthesis and downregulating UCHL1 expression, we validated the impact of NO on the Notch signalling pathway and CSC stemness. Importantly, targeting NO effectively reduced CSC populations within patient-derived organoids (PDOs) during radiotherapy. This mechanism presents a promising therapeutic target to surmount radiotherapy resistance in NSCLC treatment., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Peroxisome proliferator-activated receptors (PPARs), including PPAR-α, PPAR-β/δ, and PPAR-γ, are involved in various cellular responses, including metabolism and cell proliferation. Increasing evidence suggests that PPARs are closely associated with tumorigenesis and metastasis. However, the exact role of PPARs in energy metabolism and cancer stem cell (CSC) proliferation remains unclear. This study investigated the role of PPARs in energy metabolism and tumorigenesis in ovarian CSCs. The expression of PPARs and fatty acid consumption as an energy source increased in spheroids derived from A2780 ovarian cancer cells (A2780-SP) compared with their parental cells. GW6471, a PPARα inhibitor, induced apoptosis in A2780-SP. PPARα silencing mediated by small hairpin RNA reduced A2780-SP cell proliferation. Treatment with GW6471 significantly inhibited the respiratory oxygen consumption of A2780-SP cells, with reduced dependency on fatty acids, glucose, and glutamine. In a xenograft tumor transplantation mouse model, intraperitoneal injection of GW6471 inhibited in vivo tumor growth of A2780-SP cells. These results suggest that PPARα plays a vital role in regulating the proliferation and energy metabolism of CSCs by altering mitochondrial activity and that it offers a promising therapeutic target to eradicate CSCs.

Background/aim: The membrane-bound protein lymphocyte antigen 6 family member D (LY6D), a marker of early B cell lineage is reportedly expressed in several human malignancies and has been implicated in cancer stemness. However, its expression and role in cancer stemness remain largely unexplored in pancreatic ductal adenocarcinoma (PDAC). The aim of this study was to clarify the role of LY6D in PDAC., Materials and Methods: We conducted functional analysis of LY6D to evaluate its impact on the malignant features of PDAC cells in vitro. Using our in-house developed stem cell separation technique, which isolates cells with low proteasome activity and CD44 v9 cell surface marker for cancer stem cells, we performed sphere formation and chemosensitivity tests and tumor formation assay in mice, through knockdown of LY6D expression. Immuno-histopathological analysis was also conducted to reveal the clinical significance of LY6D in PDAC., Results: In vitro functional assays demonstrated that LY6D was critically involved in promoting the cancer malignant phenotype, including increased invasive ability, drug resistance, migration capacity, and cancer stemness. Immunohistopathological analysis revealed that high LY6D expression levels were associated with high recurrence rates and poorer prognosis in PDAC., Conclusion: Our study showed that LY6D is a novel prognostic indicator and plays a key role in regulation of cancer stemness in PDAC., (Copyright © 2024 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Glioblastoma (GBM) is categorized by the World Health Organization (WHO) as a grade 4 glioma and is a uniformly fatal tumor of the central nervous system. With the discovery of specific gene anomalies, GBM classification has been modified several times to provide better diagnostic and prognostic accuracy. Survival outcomes remain dismal despite the current therapeutic modalities, which include a combination of surgical resection, adjuvant chemotherapy, and radiotherapies, providing brief control of tumor progression. GBM remains aggressive and reoccurs primarily due to the presence of a unique population of untreatable glioblastoma stem cells (GSC). The presence of high mutation rates and a dysregulated transcriptional landscape increase GSC resistance to conventional chemotherapy and radiation therapy, contributing to poor outcomes seen in GBM patients. Accordingly, GSCs have emerged as targets of interest in new GBM treatment paradigms. Consequently, it is important to understand their distinct properties, such as GSC interactions with the hypoxic microenvironment, enhancing their growth. The epigenomic regulators and fundamental molecular components of the signaling pathways represent potential targets for GBM therapies. In this review, we aimed to describe the evolution of GBM classification and highlight the current therapeutic modalities, including gene and immunotherapies, and mammalian target of rapamycin (mTOR) inhibitors to target GBM. Furthermore, we explored the molecular pathway of GSCs and the ongoing investigation of circulating tumor cells (CTC), along with precision therapeutics, which aim to provide novel discoveries and effective treatments for GBM with improved survival., (Copyright © 2024 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Gastric cancer (GC) a prevalent form of cancer globally. Previous research suggests that SHOX2 may have a role in promoting cancer progression. However, the role of SHOX2 in GC is not well understood. Based on data from TCGA_GC data set, SHXO2 levels were examined in normal and GC tissues. Patients in the TCGA_GC cohort were divided into high- and low-SHOX2 level groups for analysis of overall survival (OS), functional enrichment, and immune infiltration. Furthermore, experiments were conducted to investigate the impact of SHOX2 on GC cell function through gain- and loss-of-function experiments. Utilizing data from public databases, SHOX2 mRNA levels were found to be elevated in GC tissues compared to normal control, this finding was confirmed by RT-qPCR, western blot analysis, and immune-histochemical analyses. Elevated SHOX2 levels could serve as an independent indicator of poor prognosis in GC patients. Furthermore, SHOX2 levels had a negative correlation with CD8 T cells and CD4 memory activated T cells, and a positive correlation with of M0 macrophages in GC patients. Functional analyses revealed that SHOX2 deficiency notably suppressed GC cell proliferation, migration, and invasion. Additionally, SHOX2 deficiency was shown to suppress stemness in GC cells in vitro and in vivo via inactivating wnt/β-catenin signaling. Collectively, SHOX2 may serve as a prognostic marker for GC patients, and downregulation of SHOX2 could effectively impede GC cell growth and stemness by inactivating the wnt/β-catenin signaling pathway. These findings underscore the potential of SHOX2 as a promising therapeutic target for GC., (© 2024 Wiley Periodicals LLC.)

Background: Cancer stem-like cells (CSLCs) drive tumour progression and chemoresistance. The concerted efforts of EXO1 and TLS polymerases safeguard DNA integrity against chemotherapeutic drugs. In absence of potential drug targets, non-small cell lung carcinoma (NSCLC) patients have few therapeutic options. In current scenario, microRNAs offer a potential avenue for eradicating CSLCs., Methods: EXO1 downregulation impact on CSLCs expansion was assessed via flow cytometry. Co-localisation of EXO1, Polη and Polι was validated through co-immunoprecipitation and confocal-imaging. The effects of co-downregulation of Polη and Polι on CSLC survival, repair synthesis, and mutagenesis were evaluated using flow cytometry and immunohistochemistry in cell lines and xenografts. MicroRNA targeting EXO1 was studied for its role in CSLCs regulation., Results: EXO1 downregulation in NSCLC CSLCs induces DNA lesions, triggering apoptosis and enhances cisplatin sensitivity. It collaborates with Polη and Polι in DNA repair, contributing to cisplatin resistance in CSLCs. Absence of Polη and Polι impairs repair and reduces cisplatin-induced mutagenesis. Co-downregulation of Polη and Polι in xenografts reduces tumour proliferation significantly. MiR-3163 overexpression sensitises CSLCs to cisplatin via targeting EXO1/Polη/Polι axis, as shown in mechanistic studies., Conclusion: This study unveils a novel regulatory pathway involving EXO1/Polη/Polι axis and miR-3163, providing insights into CSLCs regulation in NSCLC. EXO1/Polη/Polι axis targeted by miR-3163, resulting in the inhibition of cell growth and induction of apoptosis in NSCLC CSLCs., Competing Interests: Competing interests The authors declare no competing interests. Ethical approval All animal protocols were approved by the CSIR-IICB-Animal ethics committee (IICB/AEC/Meeting/July/2020/1). All methods are reported following the ARRIVE guidelines (https://arriveguidelines.org) for animal experiment reporting, with ethics approval., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Hepatocellular carcinoma (HCC) is a malignant tumor that arises from hepatocytes. Multiple signaling pathways play a regulatory role in the occurrence and development of HCC, with the Wnt signaling pathway being one of the primary regulatory pathways. In normal hepatocytes, the Wnt signaling pathway maintains cell regeneration and organ development. However, when aberrant activated, the Wnt pathway is closely associated with invasion, cancer stem cells(CSCs), drug resistance, and immune evasion in HCC. Among these factors, the development of drug resistance is one of the most important factors affecting the efficacy of HCC treatment. These mechanisms form the basis for tumor cell adaptation and evolution within the body, enabling continuous changes in tumor cells, resistance to drugs and immune system attacks, leading to metastasis and recurrence. In recent years, there have been numerous new discoveries regarding these mechanisms. An increasing number of drugs targeting the Wnt signaling pathway have been developed, with some already entering clinical trials. Therefore, this review encompasses the latest research on the role of the Wnt signaling pathway in the onset and progression of HCC, as well as advancements in its therapeutic strategies., 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 paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Colorectal cancer (CRC) is a common cancer worldwide with an increasing annual incidence. Cancer stem cells (CSCs) play important roles in the occurrence, development, recurrence, and metastasis of CRC. The molecular mechanism regulating the development of colorectal CSCs remains unclear. The discovery of human induced pluripotent stem cells (hiPSCs) through somatic cell reprogramming has revolutionized the fields of stem cell biology and translational medicine. In the present study, we converted hiPSCs into cancer stem-like cells by culture with conditioned medium (CM) from CRC cells. These transformed cells, termed hiPSC-CSCs, displayed cancer stem-like properties, including a spheroid morphology and the expression of both pluripotency and CSC markers. HiPSC-CSCs showed tumorigenic and metastatic abilities in mouse models. The epithelial-mesenchymal transition phenotype was observed in hiPSC-CSCs, which promoted their migration and angiogenesis. Interestingly, upregulation of C-MYC was observed during the differentiation of hiPSC-CSCs. Mechanistically, CREB binding protein (CBP) bound to the C-MYC promoter, while histone deacetylase 1 and 3 (HDAC1/3) dissociated from the promoter, ultimately leading to an increase in histone acetylation and C-MYC transcriptional activation during the differentiation of hiPSC-CSCs. Pharmacological treatment with a CBP inhibitor or abrogation of CBP expression with a CRISPR/Cas9-based strategy reduced the stemness of hiPSC-CSCs. This study demonstrates for the first time that colorectal CSCs can be generated from hiPSCs. The upregulation of C-MYC via histone acetylation plays a crucial role during the conversion process. Inhibition of CBP is a potential strategy for attenuating the stemness of colorectal CSCs., Competing Interests: Competing interests The authors declare no competing interests. Ethics approval and consent to participate The authors declare that all methods were performed in accordance with the relevant guidelines and regulations. The procedures for collecting human blood samples were approved by the Institutional Review Board of the National Taiwan University Hospital. Signed informed consent was obtained from all participants. Additionally, the authors have obtained written informed consent for publication of the images., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Platelet reactive protein 2 (PRP2) is closely related to the characteristics of tumor stem cells. Its role in cancer development and metastasis has received increasing attention, especially its interaction with the immune microenvironment. The study used cluster analysis to extract expression data of multiple cancer types from public databases, and combined with immune infiltration analysis, to evaluate the expression level of PRP2 and its correlation with different immune cell infiltration. Bioinformatics tools were used to analyze the correlation between PRP2 and tumor stem cell markers. The results show that PRP2 is significantly upregulated in a variety of cancers and is closely related to tumor stem cell characteristics. Immunoinfiltration analysis showed that the high expression of PRP2 was associated with a significant increase in immunosuppression-related cell infiltration. Through cluster analysis, we identified the expression pattern of PRP2 in different cancer types, indicating that it may be used as a biomarker for early diagnosis and prognosis assessment, and its expression is closely related to the immune microenvironment, indicating its important role in cancer biology and potential application value in the tumor immune microenvironment., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Prostate cancer stem cells (PCSCs) play crucial roles in therapy-resistance and metastasis in castration-resistant prostate cancer (CRPC). Certain functional link between cancer stemness and epithelial-mesenchymal transition (EMT) is involved in CRPC. However, up-stream regulators controlling these two processes in PCSCs are still poorly understood. Recently, we have shown that orphan nuclear receptor TLX can promote tumour initiation and progression in CRPC by repressing androgen receptor and oncogene-induced senescence., Methods: PCSCs were isolated from various prostate cancer cell lines and clinical tumour tissues using multiple methods for various in vitro and in vivo oncogenic growth analyses. Direct targets of TLX involved in stemness and EMT regulation were determined by specific reporter gene assays and ligand-driven modulation of TLX activity., Results: PCSCs isolated from various sources exhibited increased expression of TLX. Functional and molecular characterisation showed that TLX could function to promote cancer stemness and EMT in prostate cancer cells via its direct transactivation of CD44, SOX2, POU5F1 and NANOG, which share certain functional crosstalk in these two cellular processes., Conclusions: TLX could act as a key up-stream regulator in transcriptional control of stemness and EMT in PCSCs, which contribute to their tumorigenicity, castration-resistance and metastasis potentials in advanced prostate cancer., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Cancer stem cells (CSCs) are a major hindrance to clinical cancer treatment. Owing to their high tumorigenic and metastatic potential, CSCs are vital in malignant tumor initiation, growth, metastasis, and therapeutic resistance, leading to tumorigenesis and recurrence. Compared with normal tumor cells, CSCs express high levels of surface markers (CD44, CD90, CD133, etc.) and activate specific signaling pathways (Wnt/β-catenin, Notch, and Hedgehog). Although Current drug delivery systems (DDS) precisely target CSCs, the heterogeneity and multidrug resistance of CSCs impede CSC isolation and screening. Conversely, hydrogel DDSs exhibit good biocompatibility and high drug delivery efficiency. Hydrogels are three-dimensional (3D) spatial structures for drug encapsulation that facilitate the controlled release of bioactive molecules. Hence, hydrogels can be loaded with drugs to precisely target CSCs. Their 3D structure can also culture non-CSCs and facilitate their transformation into CSCs. for identification and isolation. Given that their elastic modulus and stiffness characteristics reflect those of the cellular microenvironment, hydrogels can simulate extracellular matrix pathways and markers to regulate CSCs, disrupting the equilibrium between CSC and non-CSC transformation. This article reviews the CSC microenvironment, metabolism, signaling pathway, and surface markers. Additionally, we summarize the existing CSC targeting strategies and explore the application of hydrogels for CSC screening and treatment. Finally, we discuss potential advances in CSC research that may lead to curative measures for tumors through targeted and precise attacks on CSCs., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Cancer stem cells (CSCs) are cancer cells that can self-renew and give rise to tumors. The multipotency of CSCs enables the generation of diverse cancer cell types and their potential for differentiation and resilience against chemotherapy and radiation. Additionally, specific biomarkers have been identified for them, such as CD24, CD34, CD44, CD47, CD90, and CD133. The CSC model suggests that a subset of CSCs within tumors is responsible for tumor growth. The tumor microenvironment (TME), including fibroblasts, immune cells, adipocytes, endothelial cells, neuroendocrine (NE) cells, extracellular matrix (ECM), and extracellular vesicles, has a part in shielding CSCs from the host immune response as well as protecting them against anticancer drugs. The regulation of cancer stem cell plasticity by cancer-associated fibroblasts (CAFs) occurs through specific signaling pathways that differ among various types of cancer, utilizing the IGF-II/IGF1R, FAK, and c-Met/FRA1/HEY1 signaling pathways. Due to the intricate dynamics of CSC proliferation, controlling their growth necessitates innovative approaches and much more research. Our current review speculates an outline of how the TME safeguards stem cells, their interaction with CSCs, and the involvement of the immune and inflammatory systems in CSC differentiation and maintenance. Several technologies have the ability to identify CSCs; however, each approach has limitations. We discuss how these methods can aid in recognizing CSCs in several cancer types, comprising brain, breast, liver, stomach, and colon cancer. Furthermore, we explore different immunotherapeutic strategies targeting CSCs, including stimulating cancer-specific T cells, modifying immunosuppressive TMEs, and antibody-mediated therapy targeting CSC markers.

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic and lethal disease. Gasdermins are primarily associated with necrosis via membrane permeabilization and pyroptosis, a lytic pro-inflammatory type of cell death. In this study, GSDMC upregulation during PDAC progression is reported. GSDMC directly induces genes related to stemness, EMT, and immune evasion. Targeting Gsdmc in murine PDAC models reprograms the immunosuppressive tumor microenvironment, rescuing the recruitment of anti-tumor immune cells through CXCL9. This not only results in diminished tumor initiation, growth and metastasis, but also enhances the response to KRAS G12D inhibition and PD-1 checkpoint blockade, respectively. Mechanistically, it is discovered that ADAM17 cleaves GSDMC, releasing nuclear fragments binding to promoter regions of stemness, metastasis, and immune evasion-related genes. Pharmacological inhibition of GSDMC cleavage or prevention of its nuclear translocation is equally effective in suppressing GSDMC's downstream targets and inhibiting PDAC progression. The findings establish GSDMC as a potential therapeutic target for enhancing treatment response in this deadly disease., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Metabolic remodeling is a pivotal feature of cancer, with cancer stem cells frequently showcasing distinctive metabolic behaviors. Nonetheless, understanding the metabolic intricacies of triple-negative breast cancer (TNBC) and breast cancer stem cells (BCSCs) has remained elusive. In this study, we meticulously characterized the metabolic profiles of TNBC and BCSCs and delved into their potential implications for TNBC treatment. Our findings illuminated the robust lipid metabolism activity within TNBC tumors, especially in BCSCs. Furthermore, we discovered that Fabp4, through its mediation of fatty acid uptake, plays a crucial role in regulating TNBC lipid metabolism. Knocking down Fabp4 or inhibiting its activity significantly suppressed TNBC tumor progression in both the MMTV-Wnt1 spontaneous TNBC model and the TNBC patient-derived xenograft model. Mechanistically, Fabp4's influence on TNBC tumor progression was linked to its regulation of mitochondrial stability, the CPT1-mediated fatty acid oxidation process, and ROS production. Notably, in a high-fat diet model, Fabp4 deficiency proved to be a substantial inhibitor of obesity-accelerated TNBC progression. Collectively, these findings shed light on the unique metabolic patterns of TNBC and BCSCs, underscore the biological significance of Fabp4-mediated fatty acid metabolism in governing TNBC progression, and offer a solid theoretical foundation for considering metabolic interventions in breast cancer treatment. SIGNIFICANCE: Triple-negative breast cancer progression and breast cancer stem cell activity can be restricted by targeting a critical regulator of lipid responses, FABP4., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Cheguo Cai reports financial support was provided by Foundation for Innovative Research Groups of the National Natural Science Foundation of China. Liya Yu reports financial support was provided by Ministry of Science and Technology of the People's Republic of China. Cheguo Cai reports financial support was provided by Fundamental Research Funds for the Central Universities. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Circadian rhythms are 24-h rhythms governing temporal organization of behavior and physiology generated by molecular clocks composed of autoregulatory transcription-translation feedback loops (TTFLs). Disruption of circadian rhythms leads to a spectrum of pathologies, including cancer by triggering or being involved in different hallmarks. Clock control of phenotypic plasticity involved in tumorigenesis operates in aberrant dedifferentiating to progenitor-like cell states, generation of cancer stem cells (CSCs) and epithelial-to-mesenchymal transition (EMT) events. Circadian rhythms might act as candidates for regulatory mechanisms of cellular senescent and functional determinants of senescence-associated secretory phenotype (SASP). Reciprocal control between clock and epigenetics sheds light on post-transcriptional regulation of circadian rhythms and opens avenues for novel anti-cancer strategies. Additionally, disrupting circadian rhythms influences microbiota communities that could be associated with altered homeostasis contributing to cancer development. Herein, we summarize recent advances in support of the nexus between disruptions of circadian rhythms and cancer hallmarks of new dimensions, thus providing novel perspectives on potentially effective treatment approaches for cancer management., Competing Interests: Declaration of competing interest We claim the following statements: No conflict of interest exists in the submission of this manuscript, and manuscript is approved by all authors for publication. I would like to declare on behalf of my co-authors that the work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part. All the authors listed have approved the manuscript that is enclosed., (Copyright © 2024 Elsevier B.V. All rights reserved.)

As the first discovered histone demethylase, LSD1 plays a vital role in maintaining pathological processes such as cancer, infection, and immune diseases. Based on previous researches, LSD1 is highly expressed in sorts of tumor cells such as acute myeloid leukemia, non-small cell lung cancer, prostate cancer, breast cancer and gastric cancer, etc. Therefore, targeting LSD1 is a prospective strategy for tumor treatment. Cancer stem cells could preserve self-renewal, cell proliferation, cell migration and malignant phenotype. So, the reduction of tumor cell stemness can effectively inhibit the growth of tumor cells, which may be a new strategy for the treatment of cancers. Up to now, there exist many researches confirming the significant role of LSD1 in regulating the stemness characteristics such as embryonic stem cells differentiation. Many reports show that inhibition of LSD1 effectively decreases the property of cancer cell stemness. However, there lacks a detailed review about the relationship between LSD1 and cancer cell stemness. Herein, in this review, we summarized the mechanisms how LSD1 regulates cell stemness comprehensively. In addition, some related inhibitors targeting LSD1 to reduce the proliferation characteristics of cancer stem cells are also described., 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 paper., (Copyright © 2024. Published by Elsevier Inc.)

Background: Despite advances in diagnosis and treatment in lung cancer, therapies still fail to improve patient management due to resistance mechanisms and relapses. As Cancer stem cells (CSCs) directly contribute to tumor growth and therapeutic resistance, their clinical detection represents a major challenge. However specific and additional CSC markers lack. Thus, our aim was to achieve selective detection of CSCs with specific glycan patterns and assess the CSCs burden to predict the risk of relapse in NSCLC tumors., Methods: The lung CSCs detection and sorting with a lectin MIX were assessed and compared to CD133 in vitro. Then, its putative role as CSC biomarker was evaluated in vivo and its clinical significance on 221 NSCLC patients., Results: We showed a significant CSCs enrichment in the MIX+ sorted fraction compared to CD133+ cells and confirmed its high tumorigenic capacity. The MIX prognostic value on the overall survival from early stages patients was validated suggesting its potential for detecting CSCs directly linked to tumor aggressiveness., Conclusion: The MIX could be more relevant for detecting and sorting CSCs than CD133. Moreover, its prognosis value could enable clinicians to better classify early-stage patients at high risk of relapse in order to tailor therapeutic decisions., (© 2024. The Author(s).)

Introduction: Local exposure to ionizing radiation (IR) can induce changes in biological processes in distant tissues and organs. Exosomes are nanoscale vesicles that transport biomolecules, mediate communication between cells and tissues, and can affect the abscopal effects of radiotherapy., Methods: Mice were treated with 8.0 Gy doses of chest and abdomen IR, after which serum samples were taken 24 h after exposure. Their serum exosomes were then isolated via ultracentrifugation and the small RNA portions were extracted for sequencing and bioinformatic analysis. Exosomes were injected intravenously into the mice to assess their ability to cross the blood-brain barrier (BBB). Glioma cells and glioma stem cells (GSCs) were examined for malignant biological behaviors, stemness, and tumorigenic capacity after co-culturing with different groups of exosomes., Results: We found that serum exosomes crossed the BBB in mice after local IR exposure-which induced decreases in the expression of BBB tight-junction proteins and increased brain endothelial cell apoptosis. Exosomes from the exposed groups promoted malignant biological behaviors, stemness, and tumorigenic capacity in glioma cells and GSCs by upregulating the expression of SOS1. Phospho-MEK1/2 and Phospho-ERK1/2, of the MAPK signaling pathway, were found to be up-regulated in cells that were co-cultured with the exposing groups of the exosomes. Further analyses demonstrated that differentially expressed levels of miR-93-5p in mouse serum exosomes regulated the cellular expression of SOS1., Conclusion: Following local IR exposure, serum exosomes cross the BBB to promote the progression of distant gliomas. Exosomal microRNAs play an important role in this process., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Endometrial cancer (EC) is a common gynecological cancer worldwide, often associated with a poor prognosis after recurrence or metastasis. Ovatodiolide (OVA) is a macrocyclic diterpenoid derived from Anisomeles indica that shows anticancer effects in various malignancies. This study aimed to evaluate the cytotoxic effects of OVA on EC cell proliferation and cancer stem cell (CSC) activity and explore its underlying molecular mechanisms. OVA treatment dose-dependently reduced the viability and colony formation of three EC cell lines (AN3CA, HEC-1A, and EMC6). It induced G2/M phase cell cycle arrest, associated with decreased cell division cycle 25C (CDC25C) expression and reduced activation of cyclin-dependent kinases 1 (CDK1) and 2 (CDK2). OVA also increased reactive oxygen species (ROS) production and DNA damage, activating the DNA damage-sensitive cell cycle checkpoint kinases 1 (CHK1) and 2 (CHK2) and upregulating the DNA damage marker γ-H2A.X variant histone (H2AX). It also suppressed the activation of mechanistic target of rapamycin kinase (mTOR) and nuclear factor kappa B (NF-κB) and downregulated glutathione peroxidase 1 (GPX1), an antioxidant enzyme counteracting oxidative stress. Moreover, OVA reduced the self-renewal capacity of CSCs, reducing the expression of key stemness proteins Nanog homeobox (NANOG) and octamer-binding transcription factor 4 (OCT4). The ROS inhibitor N-acetylcysteine attenuated the anti-proliferative and anti-CSC effects of OVA. Our findings suggest that OVA acts via ROS generation, leading to oxidative stress and DNA damage, culminating in cell cycle arrest and the suppression of CSC activity in EC. Therefore, OVA is a promising therapeutic agent for EC, either as a standalone treatment or an adjunct to existing therapies., 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 paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Cancer stem cells (CSCs) are a poorly differentiated population of malignant cells that (at least in some neoplasms) is responsible for tumor progression, resistance to therapy, and disease relapse. According to a widely accepted model, all stages of cancer progression involve the ability of neoplastic cells to evade recognition or elimination by the host immune system. In line with this notion, CSCs are not only able to cope with environmental and therapy-elicited stress better than their more differentiated counterparts but also appear to better evade tumor-targeting immune responses. We summarize epigenetic modifications of DNA and histones through which CSCs evade immune recognition or elimination, and propose that such alterations constitute promising therapeutic targets to increase the sensitivity of some malignancies to immunotherapy., Competing Interests: Declaration of interests ME is/has been holding research contracts with Ferrer International and Incyte, and receives personal fees from Quimatryx (outside the scope of this work). LG is/has been holding research contracts with Lytix Biopharma, Promontory, and Onxeo, has received consulting/advisory honoraria from Boehringer Ingelheim, AstraZeneca, OmniSEQ, Onxeo, The Longevity Labs, Inzen, Imvax, Sotio, Promontory, Noxopharm, EduCom, and the Luke Heller TECPR2 Foundation, and holds Promontory stock options (outside the scope of this work). The other authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Human ALDH comprise 19 subfamilies in which ALDH1A1, ALDH1A3, ALDH3A1, ALDH5A1, ALDH7A1, and ALDH18A1 are implicated in CSC. Studies have shown that ALDH can also be involved in drug resistance and standard chemotherapy regimens are ineffective in treating patients at the stage of disease recurrence. Existing chemotherapeutic drugs eliminate the bulk of tumors but are usually not effective against CSC which express ALDH+ population. Henceforth, targeting ALDH is convincing to treat the patient's post-relapse. Combination therapies that interlink signaling mechanisms seem promising to increase the overall disease-free survival rate. Therefore, targeting ALDH through ALDH inhibitors along with immunotherapies may create a novel platform for translational research. This review aims to fill in the gap between ALDH1 family members in relation to its cell signaling mechanisms, highlighting their potential as molecular targets to sensitize recurrent tumors and bring forward the future development concerning the current progress and draw backs. This review summarizes the role of cancer stem cells and their upregulation by maintaining the tumor microenvironment in which ALDH is specifically highlighted. It discusses the regulation of ALDH family proteins and the crosstalk between ALDH and CSC in relation to cancer metabolism. Furthermore, it establishes the correlation between ALDH involved signaling mechanisms and their specific targeted inhibitors, as well as their functional modularity, bioavailability, and mechanistic role in various cancers., 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 paper., (Copyright © 2024. Published by Elsevier Inc.)