Communications Biology

Single-cell transcriptomics reveals cellular heterogeneity and molecular stratification of cervical cancer

AbstractCervical cancer (CC) is the most common gynecological malignancy, whose cellular heterogeneity has not been fully understood. Here, we performed single-cell RNA sequencing (scRNA-seq) to survey the transcriptomes of 57,669 cells derived from three CC tumors with paired normal adjacent non-tumor (NAT) samples. Single-cell transcriptomics analysis revealed extensive heterogeneity in malignant cells of human CCs, wherein epithelial subpopulation exhibited different genomic and transcriptomic signatures. We also identified cancer-associated fibroblasts (CAFs) that may promote tumor progression of CC, and further distinguished inflammatory CAF (iCAF) and myofibroblastic CAF (myCAF). CD8+ T cell diversity revealed both proliferative (MKI67+) and non-cycling exhausted (PDCD1+) subpopulations at the end of the trajectory path. We used the epithelial signature genes derived from scRNA-seq to deconvolute bulk RNA-seq data of CC, identifying four different CC subtypes, namely hypoxia (S-H subtype), proliferation (S-P subtype), differentiation (S-D subtype), and immunoactive (S-I subtype) subtype. The S-H subtype showed the worst prognosis, while CC patients of the S-I subtype had the longest overall survival time. Our results lay the foundation for precision prognostic and therapeutic stratification of CC.

Characterizing somatic mutations in ovarian cancer germline risk regions

Abstract Epithelial ovarian cancer (EOC) genetics research has been focused on germline or somatic mutations independently. Emerging evidence suggests that the somatic mutational landscape can be shaped by the germline genetic background. In this study, we aim to unravel the role of somatic alterations within EOC germline susceptibility regions by incorporating functional annotations. We investigate somatic events, including mutational signatures, point mutations, copy number alterations, and transcription factor binding disruptions, within 33 EOC germline susceptibility regions. Our analysis identifies significant associations between candidate germline susceptibility genes and somatic mutational signatures known to be key risk factors for EOC, such as mismatch repair deficiency, age-related mutagenesis, and homologous recombination deficiency. In addition, we find somatic point mutations and copy number alterations are significantly enriched in histotype-specific active enhancers and promoters within EOC risk loci. Furthermore, we examine the impact of germline variants and somatic mutations on transcription factor binding sites, identifying cancer developmental transcription factor motifs frequently affected by both types of mutations. Overall, our study highlights the importance of integrating germline and somatic mutations with regulatory and epigenomic data to gain insights into the genetic basis of EOC.

IGF2BP3 recruits NUDT21 to regulate SPTBN1 alternative polyadenylation and drive ovarian cancer progression

Ovarian cancer (OC) is one of the deadliest gynecological malignancies. As the prevalent post-transcriptional regulation, alternative polyadenylation (APA) plays a crucial role in various tumors. Here we identify that the APA regulator NUDT21 is upregulated in OC and promotes malignant progression. We further demonstrate that IGF2BP3 interacts with NUDT21, which suggests m6A modification could regulate APA processing. Mechanistically, IGF2BP3, recognizing the m6A-modified site in intron 32 of SPTBN1, recruits NUDT21 to promote the usage of the SPTBN1 proximal polyadenylation site (PAS), thus increasing the generation of short transcripts in OC cells. Intriguingly, the SPTBN1 long variant demonstrates tumor-suppressive properties, whereas the short variant enhances oncogenic activity in OC. Subsequently, we illustrate that the long isoform inhibits tumor growth and metastasis by binding to CDK1 and blocking the G2/M phase of the cell cycle. In conclusion, this study uncovers a previously unrecognized regulatory mechanism in OC, which could provide potential therapeutic strategies for OC.

Long non-coding RNAs as a biomarker for homologous recombination deficiency and parp inhibitor sensitivity in high-grade serous ovarian cancers

Abstract Homologous recombination deficiency (HRD) and sensitivity to PARP inhibitors are key determinants of therapeutic response in high-grade serous ovarian cancer (HGSC), yet predictive biomarkers beyond BRCA1/2 mutations or genomic HRD scores remain inadequate. Here, we investigate the potential of long non-coding RNAs (lncRNAs) as predictive markers of HRD and PARP inhibitor response. We identify a panel of lncRNAs that stratifies HGSC tumors by HRD status and drug sensitivity. Among these, ENSG00000272172.1 is significantly upregulated in HRD-positive tumors and is detectable in both formalin-fixed tissue and plasma, supporting its use as a minimally invasive biomarker. Functional analyses reveal that this lncRNA contributes to genome stability by modulating replication dynamics. These findings highlight a previously unrecognized role for lncRNAs in the HRD phenotype and suggest translational potential for ENSG00000272172.1 in guiding clinical decision-making.

HKDC1 promotes ovarian cancer progression through boosting lipid metabolism and immune escape by stabilizing G6PC/G6PC2

Ovarian cancer (OC) is a significant health challenge, yet the mechanisms driving its progression remain unclear. This study explored the role of hexokinase domain-containing protein 1 (HKDC1) in OC, focusing on tumor growth, lipid metabolism, and immune evasion. Human OC cell lines (SKOV3 and HEY) and the murine OC cell line (ID8) were used to knock down and overexpress HKDC1. An ID8-based epithelial OC mouse model was established to validate the in vitro findings. Our results demonstrated that HKDC1 was upregulated in OC and promoted cell proliferation, migration, and invasion. HKDC1 enhanced lipid accumulation by elevating levels of free fatty acids (FFA), triglycerides, phospholipids, cholesterol, and neutral lipid, while upregulating key enzymes (ACC1, FASN, SCD1, HMGCS1, and HMGCR). It promoted immune escape through PD-L1 upregulation, inhibiting T cell proliferation and reducing IFN-γ, granzyme B, and perforin levels while increasing PD-1 levels. HKDC1 knockdown reversed these effects, which were restored by adding FFA. Mechanistically, HKDC1 interacted with and stabilized glucose-6-phosphatase catalytic subunits (G6PC/G6PC2), supporting its tumor-promoting functions. These findings were confirmed in an OC mouse model, highlighting HKDC1 as a key driver of OC progression through lipid biosynthesis and immune suppression, offering potential therapeutic targets.

STUB1 suppresses paclitaxel resistance in ovarian cancer through mediating HOXB3 ubiquitination to inhibit PARK7 expression

Paclitaxel (PTX) is a first-line drug for ovarian cancer (OC) treatment. However, the regulatory mechanism of STUB1 on ferroptosis and PTX resistance in OC remains unclear. Genes and proteins levels were evaluated by RT-qPCR, western blot and IHC. Cell viability and proliferation were measured by CCK-8 and clone formation. The changes of mitochondrial morphology were observed under a transmission electron microscope (TEM). Reactive oxygen species (ROS), iron, malondialdehyde (MDA) and glutathione (GSH) were measured using suitable kits. The interactions among STUB1, HOXB3 and PARK7 were validated using Co-IP, and dual luciferase reporter assay. Our study found that STUB1 was decreased and PARK7 was increased in tumor tissue, especially from chemotherapy resistant ovarian cancer tissue and resistant OC cells. STUB1 overexpression or PARK7 silencing suppressed cell growth and promoted ferroptosis in PTX-resistant OC cells, which was reversed by HOXB3 overexpression. Mechanistically, STUB1 mediated ubiquitination of HOXB3 to inhibit HOXB3 expression, and HOXB3 promoted the transcription of PARK7 by binding to the promoter region of PARK7. Furthermore, STUB1 overexpression or PARK7 silencing suppressed tumor formation in nude mice. In short, STUB1 promoted ferroptosis through regulating HOXB3/PARK7 axis, thereby suppressing chemotherapy resistance in OC.

Evaluating feature extraction in ovarian cancer cell line co-cultures using deep neural networks

Abstract Single-cell image analysis is crucial for studying drug effects on cellular morphology and phenotypic changes. Most studies focus on single cell types, overlooking the complexity of cellular interactions. Here, we establish an analysis pipeline to extract phenotypic features of cancer cells cultured with fibroblasts. Using high-content imaging, we analyze an oncology drug library across five cancer and fibroblast cell line co-culture combinations, generating 61,440 images and ∼170 million single-cell objects. Traditional phenotyping with CellProfiler achieves an average enrichment score of 62.6% for mechanisms of action, while pre-trained neural networks (EfficientNetB0 and MobileNetV2) reach 61.0% and 62.0%, respectively. Variability in enrichment scores may reflect the use of multiple drug concentrations since not all induce significant morphological changes, as well as the cellular and genetic context of the treatment. Our study highlights nuanced drug-induced phenotypic variations and underscores the morphological heterogeneity of ovarian cancer cell lines and their response to complex co-culture environments.

CPT1A-mediated MFF succinylation promotes stemness maintenance in ovarian cancer stem cells

Cancer stem cells (CSCs) play crucial roles in cancer progression, immune evasion, drug resistance, and recurrence. Understanding the mechanisms behind CSCs generation and stemness maintenance is vital for early cancer diagnosis and treatment. Here, we unveil that carnitine palmitoyltransferase 1A (CPT1A) is highly expressed in ovarian cancer stem cells (OCSCs) and is essential for maintaining stemness by regulating lipid desaturation. Studies confirmed that CPT1A enhances SREBP1 activation, upregulating SCD1 expression, and promoting lipid desaturation in OCSCs. Mechanistic studies reveal that CPT1A promotes succinylation of mitochondrial fission factor (MFF) through its lysine succinyltransferase (LSTase) activity, crucial for mitochondria-associated membranes formation and SREBP1 activation. Inhibiting CPT1A's LSTase activity with Glyburide reduces OCSCs' stemness and enhances cisplatin's anti-tumor effects against ovarian cancer in vitro and in vivo. Together, our studies highlight the significance of CPT1A's LSTase activity in maintaining OCSCs' stemness, offering potential targets and therapeutic strategies for ovarian cancer treatment.

Single-cell analysis reveals the stromal dynamics and tumor-specific characteristics in the microenvironment of ovarian cancer

Abstract High-grade serous ovarian carcinoma (HGSOC) is a heterogeneous disease, and a highstromal/desmoplastic tumor microenvironment (TME) is associated with a poor outcome. Stromal cell subtypes, including fibroblasts, myofibroblasts, and cancer-associated mesenchymal stem cells, establish a complex network of paracrine signaling pathways with tumor-infiltrating immune cells that drive effector cell tumor immune exclusion and inhibit the antitumor immune response. In this work, we integrate single-cell transcriptomics of the HGSOC TME from public and in-house datasets ( n  = 20) and stratify tumors based upon high vs. low stromal cell content. Although our cohort size is small, our analyses suggest a distinct transcriptomic landscape for immune and non-immune cells in high-stromal vs. low-stromal tumors. High-stromal tumors have a lower fraction of certain T cells, natural killer (NK) cells, and macrophages, and increased expression of CXCL12 in epithelial cancer cells and cancer-associated mesenchymal stem cells (CA-MSCs). Analysis of cell-cell communication indicate that epithelial cancer cells and CA-MSCs secrete CXCL12 that interacte with the CXCR4 receptor, which is overexpressed on NK and CD8+ T cells. Dual IHC staining show that tumor infiltrating CD8 T cells localize in proximity of CXCL12+ tumor area. Moreover, CXCL12 and/or CXCR4 antibodies confirm the immunosuppressive role of CXCL12-CXCR4 in high-stromal tumors.

The effect of inhibition of receptor tyrosine kinase AXL on DNA damage response in ovarian cancer

Abstract AXL is a receptor tyrosine kinase that is often overexpressed in cancers. It contributes to pathophysiology in cancer progression and therapeutic resistance, making it an emerging therapeutic target. The first-in-class AXL inhibitor bemcentinib (R428/BGB324) has been granted fast track designation by the U.S. Food and Drug Administration (FDA) in STK11-mutated advanced metastatic non-small cell lung cancer and was also reported to show selective sensitivity towards ovarian cancers (OC) with a Mesenchymal molecular subtype. In this study, we further explored AXL’s role in mediating DNA damage responses by using OC as a disease model. AXL inhibition using R428 resulted in the increase of DNA damage with the concurrent upregulation of DNA damage response signalling molecules. Furthermore, AXL inhibition rendered cells more sensitive to the inhibition of ATR, a crucial mediator for replication stress. Combinatory use of AXL and ATR inhibitors showed additive effects in OC. Through SILAC co-immunoprecipitation mass spectrometry, we identified a novel binding partner of AXL, SAM68, whose loss in OC cells harboured phenotypes in DNA damage responses similar to AXL inhibition. In addition, AXL- and SAM68-deficiency or R428 treatment induced elevated levels of cholesterol and upregulated genes in the cholesterol biosynthesis pathway. There might be a protective role of cholesterol in shielding cancer cells against DNA damage induced by AXL inhibition or SMA68 deficiency.

Androgen-responsive FOXP4 is a target for endometrial carcinoma

AbstractAlthough low estrogen is considered to suppress uterine endometrial carcinoma, the most cases occur in the postmenopausal stage. After menopause, the production of androgen level also declines. Therefore, to resolve the above enigma, we hypothesize that the postmenopausal decline of androgen is a trigger of its progression. In the present study, to validate this hypothesis, we examine the pathological roles of androgen/AR by analyzing clinical data, culturing endometrioid cancer cell lines, and using murine models. Clinical data show that androgen receptor (AR) expression and serum dihydrotestosterone (DHT) are associated with lower disease-free survival (DFS). DHT suppresses malignant behaviors in AR-transfected human endometrial cancer cells (ECC). In ovariectomized Ptenff/PRcre/+ mice, DHT decreases the proliferation of spontaneously developed murine ECC. In AR-transfected human ECC and Ptenff/PRcre/+ mice, DHT suppresses FOXP4 expression. FOXP4-overexpressed human ECC increases, while FOXP4-knocked-down ECC shows decreased malignant behaviors. DHT/AR-mediated ECC suppression is restored by FOXP4 overexpression. The high FOXP4 expression is significantly correlated with low postoperative DFS. These findings indicate that the androgen/AR system suppresses the malignant activity of endometrial carcinoma and that downstream FOXP4 is another target molecule. These findings will also impact developments in clinical approaches to elderly health.

NHE7 drives endometrial cancer progression by delaying senescence through cAMP/CREB/GRIN2B axis-mediated Ca²⁺ influx

Endometrial cancer (EC) remains a lethal gynecological malignancy with limited therapeutic options owing to unresolved pathogenesis. Cellular senescence acts as a key barrier against tumorigenesis in cancer cells, thus investigating its role in EC progression represents a pivotal research avenue to address these challenges. This study reveals the critical role of cellular senescence in EC progression through multi-omics profiling and functional validation. The integrative analysis of RNA-seq and clinical datasets identified Na

The role of IGF2BP3/SPOP/c-Myc loop in paclitaxel resistance of endometrial cancer

Paclitaxel combination therapy is the main chemotherapy regimen for endometrial cancer (EC); however, subsequent drug resistance is a bottleneck limiting its widespread clinical application. We found that human insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) was abnormally elevated in paclitaxel-resistant EC cells and confirmed that the reduction of IGF2BP3 can effectively improve the sensitivity of EC cells to paclitaxel in vitro and in vivo. Mechanistically, elevated IGF2BP3 promotes the half-life of c-Myc by competitively inhibiting Speckle-type POZ protein (SPOP)-mediated ubiquitination and degradation of c-Myc. As a transcription factor, c-Myc can bind to the promoter of IGF2BP3, thus contributing to the increased transcription of IGF2BP3 via positive feedback and forming a signaling loop that ultimately causes the accumulation of c-Myc-induced paclitaxel resistance. Based on these findings, the application of c-Myc inhibitors (10058-F4) combined with paclitaxel helped paclitaxel-resistant EC cells regain paclitaxel sensitivity in vitro and in vivo. Together, we reveal the underlying mechanism of paclitaxel resistance in endometrial cancer cells and provide insights into treatment strategies for paclitaxel-resistant EC patients.

L1CAM is required for early dissemination of fallopian tube carcinoma precursors to the ovary

AbstractMost ovarian high-grade serous carcinomas (HGSC) arise from Serous Tubal Intraepithelial Carcinoma (STIC) lesions in the distal end of the fallopian tube (FT). Formation of STIC lesions from FT secretory cells leads to seeding of the ovarian surface, with rapid tumor dissemination to other abdominal structures thereafter. It remains unclear how nascent malignant cells leave the FT to colonize the ovary. This report provides evidence that the L1 cell adhesion molecule (L1CAM) contributes to the ability of transformed FT secretory cells (FTSEC) to detach from the tube, survive under anchorage-independent conditions, and seed the ovarian surface. L1CAM was highly expressed on the apical cells of STIC lesions and contributed to ovarian colonization by upregulating integrins and fibronectin in malignant cells and activating the AKT and ERK pathways. These changes increased cell survival under ultra-low attachment conditions that mimic transit from the FT to the ovary. To study dissemination to the ovary, we developed a tumor-ovary co-culture model. We showed that L1CAM expression was important for FT cells to invade the ovary as a cohesive group. Our results indicate that in the early stages of HGSC development, transformed FTSECs disseminate from the FT to the ovary in a L1CAM-dependent manner.

IL-21 promotes the anti-tumor effect of anti-CD47 chimeric antigen receptor macrophages in ovarian cancer

Macrophages play a key role in immunity against solid tumors. However, their development and clinical applications are limited by their difficult-to-transfect nature, low proliferative capacity, and easily changing polarization states. The combination of chimeric antigen receptor (CAR) technology with macrophages to form chimeric antigen receptor macrophages (CAR-Ms) is an emerging strategy for adoptive cell therapy. In our previous study, we confirmed that anti-CD47 CAR-Ms have potential for ovarian cancer treatment. Here, we demonstrated that the introduction of IL-21 significantly increases the tumor-suppressive effect of anti-CD47 CAR-Ms against ovarian cancer. Specifically, IL-21-modified CAR-Ms with second-generation CARs targeting CD47 showed potent tumor cell-killing activity, both in vitro and in vivo, through direct and indirect pathways (direct phagocytosis and activation of cytotoxic T lymphocytes). In addition, an IL-21 modification significantly enhanced the tumor microenvironmental regulation of immunosuppression mediated by anti-CD47 CAR-Ms in vivo, thereby improving their therapeutic efficacy in a mouse model of ovarian cancer, without any obvious adverse effects. Taken together, these results suggest that anti-CD47 CAR-Ms combined with IL-21 is a promising treatment strategy for ovarian cancer.

Transient receptor potential canonical 3 is required for HPV-induced malignant transformation of cervical epithelial cells

Human Papillomavirus (HPV) types 16 and 18 are well-established causative agents in cervical cancer. However, the mechanism of malignant transformation remains unclear. Although epithelial-mesenchymal transition (EMT) is regulated by Ca

The chromatin landscape of high-grade serous ovarian cancer metastasis identifies regulatory drivers in post-chemotherapy residual tumour cells

AbstractDisease recurrence following chemotherapy is a major clinical challenge in ovarian cancer (OC), but little is known regarding how the tumour epigenome regulates transcriptional programs underpinning chemoresistance. We determine the single cell chromatin accessibility landscape of omental OC metastasis from treatment-naïve and neoadjuvant chemotherapy-treated patients and define the chromatin accessibility profiles of epithelial, fibroblast, myeloid and lymphoid cells. Epithelial tumour cells display open chromatin regions enriched with motifs for the oncogenic transcription factors MEIS and PBX. Post chemotherapy microenvironments show profound tumour heterogeneity and selection for cells with accessible chromatin enriched for TP53, TP63, TWIST1 and resistance-pathway-activating transcription factor binding motifs. An OC chemoresistant tumour subpopulation known to be present prior to treatment, and characterised by stress-associated gene expression, is enriched post chemotherapy. Nuclear receptors RORa, NR2F6 and HNF4G are uncovered as candidate transcriptional drivers of these cells whilst closure of binding sites for E2F2 and E2F4 indicate post-treated tumour having low proliferative capacity. Delineation of the gene regulatory landscape of ovarian cancer cells surviving chemotherapy treatment therefore reveals potential core transcriptional regulators of chemoresistance, suggesting novel therapeutic targets for improving clinical outcome.

A longitudinal pilot study in pre-menopausal women links cervicovaginal microbiome to CIN3 progression and recovery

Abstract Increasing evidence suggests vaginal dysbiosis is associated with persistent high-risk human papillomavirus (hrHPV) infection and cervical intraepithelial neoplasia (CIN) development. In this pilot longitudinal study, we investigate the potential of vaginal microbiome biomarkers to predict CIN3 development in hrHPV-positive (hrHPV+) women of reproductive age and assess loop electrosurgical excision procedure (LEEP) outcomes. Fifty-nine non-menopausal women 20–53 years old, with normal cytology, were selected from the ARTISTIC trial and followed up twice over six years. Vaginal microbiome was analysed by 16S rRNA sequencing. HrHPV+ women with CIN3 showed a significant overrepresentation of Sneathia amnii, Megasphaera genomosp., Peptostreptococcus anaerobius and Achromobacter spanius (p < 0.05). Successfully LEEP-treated hrHPV-negative women exhibited increased Lactobacillus species, especially Lactobacillus gasseri. Additionally, Lactobacillus helveticus, suntoryeus and vaginalis showed a potential protective role against CIN3 development. These unique microbial biomarkers associated with CIN3 development and recovery following LEEP treatment bring new insights into the vaginal microbiome’s role on disease progression.

Single-cell RNA sequencing reveals tumor heterogeneity in small cell neuroendocrine cervical carcinoma

Small cell neuroendocrine cervical carcinoma (SCNECC) is an aggressive gynecological malignancy with poor prognosis. The precision therapeutic strategies for SCNECC are severely limited by the complex tumor microenvironment. Here, we mapped the single-cell landscape of a total of six samples from matched SCNECC cancerous foci and normal adjacent cervical tissues. Through analysis of 68,455 high-quality cells, malignant epithelial cells were identified with increased neuroendocrine differentiation and reduced keratinization. Within four epithelial cell clusters, the key transcription factors ASCL1, NEUROD1, POU2F3, and YAP1 defined molecular subtypes. Transitional trajectory among subtypes characterized two distinct carcinogenesis pathways in SCNECC. The P-type SCNECC showed potentially enhanced immune infiltration over other subtypes. Intercellular communication analysis identified several immune checkpoints and differentially expressed signaling pathways among subtypes. Through western blotting, the TC-YIK cell line was identified as an N-type SCNECC cell with high expression of SLFN11 and mTOR. Based on immunohistochemical staining of malignant subtyping markers, a cohort of 66 SCNECC patients from our hospital were divided into five subtypes. We further combined YAP1 expression with other clinicopathological factors (Cox p < 0.05) to establish a prognostic nomogram. Overall, these findings provide clues for tumorigenesis, precision treatments and prognostic prediction in SCNECC.

SH3RF2 contributes to cisplatin resistance in ovarian cancer cells by promoting RBPMS degradation

AbstractPlatinum-based chemotherapy remains one of the major choices for treatment of ovarian cancer (OC). However, primary or acquired drug resistance severely impairs their efficiency, thereby causing chemotherapy failure and poor prognosis. SH3 domain containing ring finger 2 (SH3RF2) has been linked to the development of cancer. Here we find higher levels of SH3RF2 in the tumor tissues from cisplatin-resistant OC patients when compared to those from cisplatin-sensitive patients. Similarly, cisplatin-resistant OC cells also express higher levels of SH3RF2 than normal OC cells. Through in vitro and in vivo loss-of-function experiments, SH3RF2 is identified as a driver of cisplatin resistance, as evidenced by increases in cisplatin-induced cell apoptosis and DNA damage and decreases in cell proliferation induced by SH3RF2 depletion. Mechanistically, SH3RF2 can directly bind to the RNA-binding protein mRNA processing factor (RBPMS). RBPMS has been reported as an inhibitor of cisplatin resistance in OC. As a E3 ligase, SH3RF2 promotes the K48-linked ubiquitination of RBPMS to increase its proteasomal degradation and activator protein 1 (AP-1) transactivation. Impairments in RBPMS function reverse the inhibitory effect of SH3RF2 depletion on cisplatin resistance. Collectively, the SH3RF2-RBPMS-AP-1 axis is an important regulator in cisplatin resistance and inhibition of SH3RF2 may be a potential target in preventing cisplatin resistance.

Single-cell and spatial transcriptomic profiling reveals distinct tumor microenvironment dynamics in cervical adenocarcinoma and squamous cell carcinoma

Cervical cancer (CC), a leading cause of cancer-related deaths among women worldwide, is primarily driven by high-risk human papillomavirus (HPV) infections and comprises two major histological subtypes: adenocarcinoma (AC) and squamous cell carcinoma (SCC). Despite advances in prevention and treatment, the molecular and cellular heterogeneity of these subtypes poses significant challenges to achieving optimal clinical outcomes. Here, we integrate single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics (ST) to dissect the cellular and spatial heterogeneity of AC and SCC, uncovering distinct tumor microenvironment (TME) dynamics that underlie their divergent clinical behaviors. Our scRNA-seq analysis reveals that AC is enriched in epithelial cells, while SCC exhibits a more immunogenic TME with elevated plasma cells and NK/T cells. Spatial transcriptomics further highlights robust interactions between CD8 + T cells and epithelial subtypes in SCC, contrasting with the stromal-rich, immune-cold phenotype of AC. We identify subtype-specific immune and stromal features, including ICOS+ Tregs, IDO1+ cancer-associated fibroblasts (CAFs), and PLVAP+ endothelial cells, which may drive immune evasion, angiogenesis, and metastasis. These findings provide a comprehensive framework for understanding CC heterogeneity and offer actionable insights for developing subtype-specific therapeutic strategies, such as combining immune checkpoint inhibitors with stromal-targeting agents. This study underscores the potential of spatial multi-omics technologies to advance precision oncology and improve outcomes for cervical cancer patients.

CG&gt;TG mutation frequency as negative predictor of homologous recombination deficiency in ovarian and breast cancer

Abstract Homologous recombination deficiency (HRD) is a predictive biomarker for PARP inhibition and platinum-based chemotherapy. While copy number alteration-based scores such as HRDsum = LST + TAI + LOH are included in therapy approvals, single base substitutions (SBS) are underinvestigated as predictors of HRD. WES data of the TCGA pan-cancer cohort and an in-house ovarian cancer cohort were annotated by alterations in BRCA1/2 and additional genes causative of HRD. Using this reference, the new biomarker fdeam defined as frequency of C &gt; T transitions at CpG sites in relation to all SBS and HRDsum were compared for the detection of HRD. In the TCGA ovarian cancer, the in-house, and the TCGA breast cancer cohorts, fdeam performed non-inferior to HRDsum (AUC = 0.84, AUC = 0.85, and AUC = 0.88). The cutpoint fdeam = 13.1% maximized the balanced accuracy in the TCGA ovarian cancer cohort and resulted in sensitivity = 89% and specificity = 77% in the in-house cohort. In a simulation study, fdeam retained high sensitivity for HRD detection and outperformed HRDsum in tumors of purity 40%, 20%, and 10%. Overcoming the limited robustness against low tumor purity, the new biomarker can contribute to a more sensitive detection of HRD in clinical samples. Further studies are warranted to confirm its clinical validity and utility and explore its potential for liquid biopsies.

M2 macrophage-derived exosomal circTMCO3 acts through miR-515-5p and ITGA8 to enhance malignancy in ovarian cancer

AbstractTumor-associated macrophages of the M2 phenotype promote cancer initiation and progression. Importantly, M2 macrophage-derived exosomes play key roles in the malignancy of cancer cells. Here, we report that circTMCO3 is upregulated in ovarian cancer patients, and its high expression indicates poor survival. M2-derived exosomes promote proliferation, migration, and invasion in ovarian cancer, but these effects are abolished by knockdown of circTMCO3. Furthermore, circTMCO3 functions as a competing endogenous RNA for miR-515-5p to reduce its abundance, thus upregulating ITGA8 in ovarian cancer. miR-515-5p inhibits ovarian cancer malignancy via directly downregulating ITGA8. The decreased oncogenic activity of circTMCO3-silencing exosomes is reversed by miR-515-5p knockdown or ITGA8 overexpression. Exosomal circTMCO3 promotes ovarian cancer progression in nude mice. Thus, M2 macrophage-derived exosomes promote malignancy by delivering circTMCO3 and targeting the miR-515-5p/ITGA8 axis in ovarian cancer. Our findings not only provide mechanistic insights into ovarian cancer progression, but also suggest potential therapeutic targets.

CAF-derived GLUT1 and its role in modulating ovarian cancer progression: a multi-dimensional analysis of the tumor microenvironment

Deciphering the reprogramming of glucose metabolism in cancer-associated fibroblasts (CAFs) within the ovarian cancer (OC) microenvironment is essential for understanding tumor progression. While CAFs are known to influence tumor metabolism, the specific mechanisms underlying their role in metabolic adaptation remain unclear. Here, we show that GLUT1 is highly expressed in CAFs and promotes glucose uptake, glycolysis, and lactate production, which in turn drives OC cell proliferation and migration via the TGF-β1/p38/MMP2/MMP9 pathway. Single-cell RNA sequencing and bioinformatics analyses identify GLUT1 as a key metabolic regulator in CAFs, and 3D bioprinting models further confirm its role in shaping the tumor microenvironment. These findings highlight GLUT1 as a potential therapeutic target for OC and provide new insights into tumor metabolism and metastasis.

TTK activates ATR through RPA2 phosphorylation to promote olaparib resistance in ovarian cancer

Resistance to poly(ADP‒ribose) polymerase inhibitors (PARPis) remains a significant challenge in ovarian cancer (OC) treatment. TTK protein kinase (TTK) has been implicated in cisplatin resistance in OC, but its role in PARPi resistance remains unclear. In this research, we found that TTK inhibition overcome olaparib resistance in HR-proficient OC cells, whereas TTK promotes olaparib resistance in HR-deficient OC cells. Mechanistically, TTK directly interacts with RPA2, facilitating phosphorylation of its S33 residue to activate the ATR signaling pathway. Knocking down RPA2 increased olaparib sensitivity in OC cells. Additionally, TTK-mediated resistance to olaparib through the RPA2/ATR signaling pathway was confirmed via both in vitro and in vivo models. In conclusion, TTK inhibition overcomes olaparib resistance in HR-proficient OC cells, in part by suppressing RPA2-S33 phosphorylation and attenuating ATR signaling. TTK inhibitors offer a promising strategy to increase the therapeutic efficacy of PARPis in OC patients.

Druggable genome CRISPR screening identifies the KEAP1/NRF2 axis as a mediator of PD-L1 expression

Cancer cells rapidly induce PD-L1 expression in response to inflammatory cytokines such as IFNγ from cytotoxic T cells. Increased surface PD-L1 is a primary mechanism of cancer cells evading cytotoxic T-cell-mediated immune clearance. Identifying how cancer cells increase PD-L1 expression may yield clinically relevant immune checkpoint regulators. However, the key regulators and molecular mechanisms mediating rapid PD-L1 induction are yet to be understood entirely. To identify targetable mechanisms controlling cytokine-induced PD-L1 expression, we performed functional CRISPR gene KO screening with a custom-designed sgRNA library that targets "druggable" genes. We performed the screening in 6 different cancer lines: 3 ovarian (OVCAR4, CaOV3, and SKOV3) and three pancreatic cancer (MiaPaca2, ASPC1 and KP4) cell lines. The screening recovered the known regulators of PD-L1 expression and uncovered several novel regulators of PD-L1 that control its expression in all cell lines or in a cancer-type-specific fashion. For example, while genetic or pharmacological depletion of CSNK1A1 results in reduced PD-L1 expression in ovarian cancer cells, CDK1 depletion modulates PD-L1 in pancreatic cancer cell lines. Significantly, we discovered that KEAP1 depletion or pharmacological inhibition diminishes PD-L1 in all cell lines tested (n = 6). Mechanistically, KEAP1 depletion-mediated reduced PD-L1 is due to transcriptional repression of the PD-L1 gene by NRF2 activation. As such, depletion of NRF2 restores PD-L1 expression, while its overexpression leads to diminished PD-L1 expression. Supporting this, pharmacological NRF2 activation resulted in significant antitumor immunity with increased cytotoxic effector T cell infiltration and reduced exhausted T cells, resulting in smaller xenografted tumors. These findings establish the KEAP1/NRF2 axis as a novel and potentially druggable mechanism of IFNγ-meditated PD-L1 expression in cancer cells.

FUS-dependent loading of SUV39H1 to OCT4 pseudogene-lncRNA programs a silencing complex with OCT4 promoter specificity

AbstractThe resurrection of pseudogenes during evolution produced lncRNAs with new biological function. Here we show that pseudogene-evolution created an Oct4 pseudogene lncRNA that is able to direct epigenetic silencing of the parental Oct4 gene via a 2-step, lncRNA dependent mechanism. The murine Oct4 pseudogene 4 (mOct4P4) lncRNA recruits the RNA binding protein FUS to allow the binding of the SUV39H1 HMTase to a defined mOct4P4 lncRNA sequence element. The mOct4P4-FUS-SUV39H1 silencing complex holds target site specificity for the parental Oct4 promoter and interference with individual components results in loss of Oct4 silencing. SUV39H1 and FUS do not bind parental Oct4 mRNA, confirming the acquisition of a new biological function by the mOct4P4 lncRNA. Importantly, all features of mOct4P4 function are recapitulated by the human hOCT4P3 pseudogene lncRNA, indicating evolutionary conservation. Our data highlight the biological relevance of rapidly evolving lncRNAs that infiltrate into central epigenetic regulatory circuits in vertebrate cells.

Omental macrophages secrete chemokine ligands that promote ovarian cancer colonization of the omentum via CCR1

AbstractThe omentum is the most common site of ovarian cancer metastasis. Immune cell clusters called milky spots are found throughout the omentum. It is however unknown if these immune cells contribute to ovarian cancer metastasis. Here we report that omental macrophages promote the migration and colonization of ovarian cancer cells to the omentum through the secretion of chemokine ligands that interact with chemokine receptor 1 (CCR1). We found that depletion of macrophages reduces ovarian cancer colonization of the omentum. RNA-sequencing of macrophages isolated from mouse omentum and mesenteric adipose tissue revealed a specific enrichment of chemokine ligand CCL6 in omental macrophages. CCL6 and the human homolog CCL23 were both necessary and sufficient to promote ovarian cancer migration by activating ERK1/2 and PI3K pathways. Importantly, inhibition of CCR1 reduced ovarian cancer colonization. These findings demonstrate a critical mechanism of omental macrophage induced colonization by ovarian cancer cells via CCR1 signaling.

RAS/PI3K pathway mutations sensitise epithelial ovarian cancer cells to a PARP/NAMPT inhibitor combination

Abstract The combination of PARP and NAMPT inhibitors (PARPi/NAMPTi) has been explored for the treatment of triple-negative breast cancer, Ewing sarcoma and high-grade serous carcinoma (HGSC). However, dose limiting toxicity has hampered NAMPTi in clinical trials. To maximise the therapeutic window, we set out to identify predictive genomic biomarkers. Bioinformatic analysis and screening of a panel of epithelial ovarian cancer (EOC) cell lines revealed that cells with RAS/PI3K pathway mutations are sensitive to the NAMPTi FK866. Combined exposure to olaparib and FK866 is associated with a reduction in nicotinamide mononucleotide (NMN) and the PARP substrate nicotinamide adenine dinucleotide (NAD + ), with coincident increases in ROS production, DNA damage and apoptosis induction. Caspase 3/7 activity is upregulated to a greater extent in RAS/PI3K mutant cell lines. Finally, the combination significantly reduces omental tumour weight and increases overall survival in mice injected with ID8 Trp53 -/- ;Pten -/- cells. This study highlights the potential of the PARPi/NAMPTi combination in RAS/PI3K pathway mutant EOC.

Overcoming platinum-resistant ovarian cancer targeting the activated JAK-STAT pathways via extracellular vesicles

Abstract Platinum-resistant ovarian cancer (PROC) is a clinically severe unresolved issue, and it remains unclearly defined by molecular biology. Extracellular vesicles (EVs) play an essential role in cell-to-cell communication in the tumor microenvironment. This study aimed to investigate the molecular mechanisms of PROC, focusing on the unique ascites environment of ovarian cancer. Multi-transcriptome analyses using clinical samples revealed that PROC exhibited an activated Janus kinase (JAK)/signal transducer and activator of transcription pathway with high JAK1 expression in cancer cells. Immunohistochemistry for patient tissues confirmed the negative association between JAK1 expression and platinum response. JAK inhibitors were effective in PROC cell lines and cell- and patient-derived xenograft models, as well as synergistic with platinum. Furthermore, small RNA sequencing indicated that activated peritoneal mesothelial cell-derived EVs enriched in miR135a-5p increased JAK expression and platinum resistance in cancer cells. Collectively, EVs in ascites regulated platinum sensitivity in ovarian cancer cells, and JAK targeting therapeutic strategy overcomes PROC.

Dicalcin suppresses invasion and metastasis of mammalian ovarian cancer cells by regulating the ganglioside-Erk1/2 axis

AbstractMetastasis, a multistep process including cancer cell migration and invasion, is the major cause of mortality in patients with cancer. Here, we investigated the effect of dicalcin, a Ca2+-binding protein, on the invasion and metastasis of ovarian cancer (OC) cells. Extracellularly administered dicalcin bound to the membrane of OV2944 cells, mouse OC cells, and suppressed their migration in vitro; however, cell viability or proliferation were unaffected. Repeated intraperitoneal injection of a partial peptide of dicalcin (P6) prolonged the survival, and reduced the number of microcolonies in the livers of cancer-bearing mice. P6 bound to the ganglioside GM1b in a solid-phase assay; treatment with P6 inhibited the constitutive activation of Erk1/2 in OC cells, whereas excess administration of GM1b augmented Erk activity and cancer cell migration in vitro. Thus, dicalcin, a novel suppressor of invasion and metastasis of OC cells, acts via the GM1b-Erk1/2 axis to regulate their migration.

Carnitine palmitoyltransferase 1A promotes mitochondrial fission by enhancing MFF succinylation in ovarian cancer

Abstract Mitochondria are dynamic organelles that are important for cell growth and proliferation. Dysregulated mitochondrial dynamics are highly associated with the initiation and progression of various cancers, including ovarian cancer. However, the regulatory mechanism underlying mitochondrial dynamics is still not fully understood. Previously, our study showed that carnitine palmitoyltransferase 1A (CPT1A) is highly expressed in ovarian cancer cells and promotes the development of ovarian cancer. Here, we find that CPT1A regulates mitochondrial dynamics and promotes mitochondrial fission in ovarian cancer cells. Our study futher shows that CPT1A regulates mitochondrial fission and function through mitochondrial fission factor (MFF) to promote the growth and proliferation of ovarian cancer cells. Mechanistically, we show that CPT1A promotes succinylation of MFF at lysine 302 (K302), which protects against Parkin-mediated ubiquitin-proteasomal degradation of MFF. Finally, the study shows that MFF is highly expressed in ovarian cancer cells and that high MFF expression is associated with poor prognosis in patients with ovarian cancer. MFF inhibition significantly inhibits the progression of ovarian cancer in vivo. Overall, CPT1A regulates mitochondrial dynamics through MFF succinylation to promote the development of ovarian cancer. Moreover, our findings suggest that MFF is a potential therapeutic target for ovarian cancer.

TriFusion enables accurate prediction of miRNA-disease association by a tri-channel fusion neural network

The identification of miRNA-disease associations is crucial for early disease prevention and treatment. However, it is still a computational challenge to accurately predict such associations due to improper information encoding. Previous methods characterize miRNA-disease associations only from single levels, causing the loss of multi-level association information. In this study, we propose TriFusion, a powerful and interpretable deep learning framework for miRNA-disease association prediction. It develops a tri-channel architecture to encode the association features of miRNAs and diseases from different levels and designs a feature fusion encoder to smoothly fuse these features. After training and testing, TriFusion outperforms other leading methods and offers strong interpretability through its learned representations. Furthermore, TriFusion is applied to three high-risk sexually associated cancers (ovarian, breast, and prostate cancers) and exhibits remarkable ability in the identification of miRNAs associated with the three diseases.

Comparative analysis of syngeneic mouse models of high-grade serous ovarian cancer

Abstract Ovarian cancers exhibit high rates of recurrence and poor treatment response. Preclinical models that recapitulate human disease are critical to develop new therapeutic approaches. Syngeneic mouse models allow for the generation of tumours comprising the full repertoire of non-malignant cell types but have expanded in number, varying in the cell type of origin, method for transformation, and ultimately, the properties of the tumours they produce. Here we have performed a comparative analysis of high-grade serous ovarian cancer models based on transcriptomic profiling of 22 cell line models, and intrabursal and intraperitoneal tumours from 12. Among cell lines, we identify distinct signalling activity, such as elevated inflammatory signalling in STOSE and OVE16 models, and MAPK/ERK signalling in ID8 and OVE4 models; metabolic differences, such as reduced glycolysis-associated expression in several engineered ID8 subclones; and relevant functional properties, including differences in EMT activation, PD-L1 and MHC class I expression, and predicted chemosensitivity. Among tumour samples, we observe increased variability and stromal content among intrabursal tumours. Finally, we predict differences in the microenvironment of ID8 models engineered with clinically relevant mutations. We anticipate that this work will serve as a valuable resource, providing new insight to help select models for specific experimental objectives.

A magnetic antibody-conjugated nano-system for selective delivery of Ca(OH)2 and taxotere in ovarian cancer cells

AbstractAn efficient strategy for cancer therapy is presented, in which a tumor mass is initially pretreated with calcium hydroxide, then treated with Taxotere (TXT). In this regard, an advanced delivery system based on iron oxide nanoparticles has been designed. The surface of nanoparticles was functionalized with sortilin (SORT-1, a human IgG1 monoclonal antibody) that specifically encodes caov-4 ovarian cancerous cells. Plasmonic heating of the incorporated gold nanoparticles in polyvinyl alcohol (PVA) has been exploited to control the release process of TXT. The in vitro, ex vivo and in vivo experiments have exhibited high efficacy of a seven-day pretreatment by Ca(OH)2 plus 14 days treatment program by Ca(OH)2@Fe3O4/PVA/Au-SORT nano-therapeutics, where more penetration ratio resulted in tumor growth inhibition by ca. 78.3%. As a result, due to showing high values of the anti-tumor properties and biosafety, the presented pretreatment strategy is suggested for more effective treatment on the aged tumors.

Pigment epithelium-derived factor promotes peritoneal dissemination of ovarian cancer through induction of immunosuppressive macrophages

AbstractPeritoneal dissemination of ovarian cancer (OC) correlates with poor prognosis, but the mechanisms underlying the escape of OC cells from the intraperitoneal immune system have remained unknown. We here identify pigment epithelium–derived factor (PEDF) as a promoting factor of OC dissemination, which functions through induction of CD206+ Interleukin-10 (IL-10)–producing macrophages. High PEDF gene expression in tumors is associated with poor prognosis in OC patients. Concentrations of PEDF in ascites and serum are significantly higher in OC patients than those with more benign tumors and correlated with early recurrence of OC patients, suggesting that PEDF might serve as a prognostic biomarker. Bromodomain and extraterminal (BET) inhibitors reduce PEDF expression and limit both OC cell survival and CD206+ macrophage induction in the peritoneal cavity. Our results thus implicate PEDF as a driver of OC dissemination and identify a BET protein–PEDF–IL-10 axis as a promising therapeutic target for OC.

OTUD6A promotes prostate tumorigenesis via deubiquitinating Brg1 and AR

AbstractOvarian tumor (OTU) subfamily deubiquitinases are involved in various cellular processes, such as inflammation, ferroptosis and tumorigenesis; however, their pathological roles in prostate cancer (PCa) remain largely unexplored. In this study, we observed that several OTU members displayed genomic amplification in PCa, among which ovarian tumor deubiquitinase 6A (OTUD6A) amplified in the top around 15–20%. Further clinical investigation showed that the OTUD6A protein was highly expressed in prostate tumors, and increased OTUD6A expression correlated with a higher biochemical recurrence risk after prostatectomy. Biologically, wild-type but not a catalytically inactive mutant form of OTUD6A was required for PCa cell progression. In vivo experiments demonstrated that OTUD6A oligonucleotides markedly suppressed prostate tumorigenesis in PtenPC−/− mice and patient-derived xenograft (PDX) models. Mechanistically, the SWI/SNF ATPase subunit Brg1 and the nuclear receptor AR (androgen receptor) were identified as essential substrates for OTUD6A in PCa cells by a mass spectrometry (MS) screening approach. Furthermore, OTUD6A stabilized these two proteins by erasing the K27-linked polyubiquitination of Brg1 and K11-linked polyubiquitination of AR. OTUD6A amplification exhibited strong mutual exclusivity with mutations in the tumor suppressors FBXW7 and SPOP. Collectively, our results indicate the therapeutic potential of targeting OTUD6A as a deubiquitinase of Brg1 and AR for PCa treatment.

Lin28, a major translation reprogramming factor, gains access to YB-1-packaged mRNA through its cold-shock domain

AbstractThe RNA-binding protein Lin28 (Lin28a) is an important pluripotency factor that reprograms translation and promotes cancer progression. Although Lin28 blocks let-7 microRNA maturation, Lin28 also binds to a large set of cytoplasmic mRNAs directly. However, how Lin28 regulates the processing of many mRNAs to reprogram global translation remains unknown. We show here, using a structural and cellular approach, a mixing of Lin28 with YB-1 (YBX1) in the presence of mRNA owing to their cold-shock domain, a conserved β-barrel structure that binds to ssRNA cooperatively. In contrast, the other RNA binding-proteins without cold-shock domains tested, HuR, G3BP-1, FUS and LARP-6, did not mix with YB-1. Given that YB-1 is the core component of dormant mRNPs, a model in which Lin28 gains access to mRNPs through its co-association with YB-1 to mRNA may provide a means for Lin28 to reprogram translation. We anticipate that the translational plasticity provided by mRNPs may contribute to Lin28 functions in development and adaptation of cancer cells to an adverse environment.

Gut microbiome diversity is an independent predictor of survival in cervical cancer patients receiving chemoradiation

AbstractDiversity of the gut microbiome is associated with higher response rates for cancer patients receiving immunotherapy but has not been investigated in patients receiving radiation therapy. Additionally, current studies investigating the gut microbiome and outcomes in cancer patients may not have adjusted for established risk factors. Here, we sought to determine if diversity and composition of the gut microbiome was independently associated with survival in cervical cancer patients receiving chemoradiation. Our study demonstrates that the diversity of gut microbiota is associated with a favorable response to chemoradiation. Additionally, compositional variation among patients correlated with short term and long-term survival. Short term survivor fecal samples were significantly enriched in Porphyromonas, Porphyromonadaceae, and Dialister, whereas long term survivor samples were significantly enriched in Escherichia Shigella, Enterobacteriaceae, and Enterobacteriales. Moreover, analysis of immune cells from cervical tumor brush samples by flow cytometry revealed that patients with a high microbiome diversity had increased tumor infiltration of CD4+ lymphocytes as well as activated subsets of CD4 cells expressing ki67+ and CD69+ over the course of radiation therapy. Modulation of the gut microbiota before chemoradiation might provide an alternative way to enhance treatment efficacy and improve treatment outcomes in cervical cancer patients.

Biocompatible nucleus-targeted graphene quantum dots for selective killing of cancer cells via DNA damage

AbstractGraphene quantum dots (GQDs) are nano-sized graphene slices. With their small size, lamellar and aromatic-ring structure, GQDs tend to enter into the cell nucleus and interfere with DNA activity. Thus, GQD alone is expected to be an anticancer reagent. Herein, we developed GQDs that suppress the growth of tumor by selectively damaging the DNA of cancer cells. The amine-functionalized GQDs were modified with nucleus targeting TAT peptides (TAT-NGs) and further grafted with cancer-cell-targeting folic acid (FA) modified PEG via disulfide linkage (FAPEG-TNGs). The resulting FAPEG-TNGs exhibited good biocompatibility, nucleus uptake, and cancer cell targeting. They adsorb on DNA via the π–π and electrostatic interactions, which induce the DNA damage, the upregulation of the cell apoptosis related proteins, and the suppression of cancer cell growth, ultimately. This work presents a rational design of GQDs that induce the DNA damage to realize high therapeutic performance, leading to a distinct chemotherapy strategy for targeted tumor therapy.

Immunometabolic and potential tumor-promoting changes in 3D cervical cell models infected with bacterial vaginosis-associated bacteria

AbstractSpecific bacteria of the human microbiome influence carcinogenesis at diverse anatomical sites. Bacterial vaginosis (BV) is the most common vaginal disorder in premenopausal women that is associated with gynecologic sequelae, including cervical cancer. BV-associated microorganisms, such as Fusobacterium, Lancefieldella, Peptoniphilus, and Porphyromonas have been associated with gynecologic and other cancers, though the pro-oncogenic mechanisms employed by these bacteria are poorly understood. Here, we integrated a multi-omics approach with our three-dimensional (3-D) cervical epithelial cell culture model to investigate how understudied BV-associated bacteria linked to gynecologic neoplasia influence hallmarks of cancer in vitro. Lancefieldella parvulum and Peptoniphilus lacrimalis elicited robust proinflammatory responses in 3-D cervical cells. Fusobacterium nucleatum and Fusobacterium gonidiaformans modulated metabolic hallmarks of cancer corresponding to accumulation of 2-hydroxyglutarate, pro-inflammatory lipids, and signs of oxidative stress and genotoxic hydrogen sulfide. This study provides mechanistic insights into how gynecologic cancer-associated bacteria might facilitate a tumor-promoting microenvironment in the human cervix.

EPI-SauriCas9-based mouse ovarian cancer models recapitulating pten deletion in patients

Abstract Ovarian cancer remains a deadly gynecological malignancy, with PTEN loss and TP53 mutations frequently implicated in its progression. However, suitable models for studying ovarian cancers with PTEN and TP53 deletions are rare. Here we develop and validate the mouse ovarian epithelium with Pten and Trp53 deletions (MEPP) model using the EPI-SauriCas9 system. We demonstrate the role of Pten loss in promoting tumorigenicity and metastasis. Single-cell RNA sequencing reveals distinct epithelial subpopulations with varying metastatic potential. MEPP also recapitulates key features of human ovarian cancer, including its immune landscape and therapeutic responses. High-throughput drug screening identifies FK228 and thioguanine as promising therapeutic candidates, both of which show in vivo efficacy and are validated in PTEN -deleted organoids. Together, these results establish MEPP as a platform for studying PTEN- deleted ovarian cancer and provide a strategy for generating clinically relevant tumor models through targeted gene editing.