Development Of Ovarian Cancer Research Articles

Construction and analysis of competitive endogenous RNA networks and prognostic models associated with ovarian cancer based on the exoRBase database.

To construct a competitive endogenous RNA (ceRNA) regulatory network in blood exosomes of patients with ovarian cancer (OC) using bioinformatics and explore its pathogenesis. The exoRbase2.0 database was used to download blood exosome gene sequencing data from patients OC and normal controls and the expression profiles of exosomal mRNA, long non-coding RNA (lncRNA), and circular RNA (circRNA) were detected independently using R language for differential expression analysis. TargetScan and miRanda databases were combined for the prediction and differential expression of mRNA-binding microRNAs (miRNA). The miRcode and starBase databases were used to predict miRNAs that bind to differentially expressed lncRNAs and circRNAs repectively. The relevant mRNA, circRNA, lncRNA and their corresponding miRNA prediction data were imported into Cytoscape software for visualization of the ceRNA network. The R language and KEGG Orthology-based Annotation System (KOBAS) were used to execute and illustrate the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Hub genes were identified using The CytoHubba plugin. Thirty-one differentially expressed mRNAs, 17 differentially expressed lncRNAs, and 24 differentially expressed circRNAs were screened. Cytoscape software was used to construct the ceRNA network with nine mRNA nodes, two lncRNA nodes, eight circRNA nodes, and 51 miRNA nodes. Both GO and KEGG were focused on the Spliceosome pathway, indicating that spliceosomes are closely linked with the development of OC, while heterogenous nuclear ribonucleoprotein K and RNA binding motif protein X-linked genes were the top 10 score Hub genes screened by Cytoscape software, including two lncRNAs, four mRNAs, and four circRNAs. In patients with OC, the expression of eukaryotic translation initiation factor 4 gamma 2 (EIF4G2), SERPINE 1 mRNA binding protein 1 (SERBP1), ribosomal protein L15 (RPL15) and human leukocyte antigen complex P5 (HCP5) was significantly higher whereas that of testis expressed transcript, Y-linked 15 and DEAD-box helicase 3 Y-linked genes was lower compared to normal controls Immunocorrelation scores revealed that SERBP1 was significantly and negatively correlated with endothelial cells and CD4+ T cells and positively correlated with natural killer (NK) cells and macrophages, respectively; RPL15 was significantly positively correlated with macrophages and endothelial cells and negatively correlated with CD8+ T cells and uncharacterized cells, respectively. EIF4G2 was significantly and negatively correlated with endothelial cells and CD4+ T cells, and positively correlated with uncharacterized cells, respectively. Based on the survival data and the significant correlation characteristics derived from the multifactorial Cox analysis (P < 0.05), the survival prediction curves demonstrated that the prognostic factors associated with 3-year survival in patients with OC were The prognostic factors associated with survival were Macrophage, RPL15. This study successfully constructs a ceRNA regulatory network in blood exosomes of OV patients, which provides the specific targets for diagnosis and treatment of OC.

Abstract LB318: Exploring early precursor lesions of ovarian cancer: Insights from an in vitro model

Abstract Ovarian cancer ranks as the fifth leading cause of cancer-related deaths in women, surpassing other cancers of the female reproductive system. Recent epidemiological and molecular studies highlight the significance of high-grade serous carcinoma (HGSC), the most aggressive subtype of ovarian cancer, constituting nearly 96% of cases with mutations in p53. HGSC originates from fallopian tube secretory epithelial (FTSEC) cells through a progression of precursor lesions, ranging from p53 signatures to serous tubal intraepithelial carcinoma (STIC). The p53 signature involves a linear expansion of over 12 TP53 mutant FTSECs, morphologically normal and displaying no increase in proliferative activity. In this study, we established a model system for P53 signature by either overexpressing p53 mutations (R175H and R273H) or knocking down P53 expression in normal FTSECs maintained as 2D, 3D, or organoid cultures. We have characterized the cells using RNA seq, mass spectroscopy and functional assays. Functional assays revealed increased migration and proliferation, along with decreased apoptosis in response to the cytotoxic stimulus (cisplatin). Despite the inability of p53 signature cells to proliferate or migrate in vivo, our hypothesis posited that clonal expansion of progenitor cell with a p53 mutation maintains plasticity by preserving the stemness of one or more cells capable of responding to cues from the microenvironment. Our experiments revealed heterogeneity in the model system, reflecting the composition of p53 signature in vivo. We also observed that stem-like cells tend to organize into clusters. Notably, stem-like cluster cells bearing a p53 signature exhibit migratory behavior, whereas clusters lacking p53 do not demonstrate such mobility. Given that most high-grade serous carcinoma (HGSC) cases occur in postmenopausal women, we demonstrated induction of proliferation and migration of p53 mutant stem cells in response to stimuli from aging stromal cells (fibroblasts and autologous immune cells) and to changes in hormonal background in our model. Conclusion: This study illuminates a novel aspect of ovarian cancer development, underscoring the role of a distinct population of fallopian tube epithelial cells with stem-like properties within p53 signatures. Further investigations into the tumorigenicity of these cells hold promise for providing valuable insights into future therapeutic strategies. Citation Format: Yan E. Wang, Vera Levina, Deborah L. Galson, Anna E. Lokshin. Exploring early precursor lesions of ovarian cancer: Insights from an in vitro model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB318.

Abstract LB311: Multimodal spatial profiling reveals the emergence of an immune suppressive microenvironment at the initial stages of high-grade serous ovarian cancer development

Abstract Introduction: Despite the clear genetic evidence linking serous tubal intraepithelial carcinoma (STIC) and high-grade serous ovarian carcinoma (HGSOC), the specific conditions and events that promote the progression of STIC lesions into invasive disease remain poorly understood. Method: As a critical initial step, we have assembled a cohort of incidental p53 signatures, STIC lesions, and STIC with concurrent HGSOC. We have performed extensive multi-modal analysis using multiplexed tissue imaging and spatial transcriptomics that identify features of the immune system that play a vital role in the early steps of HGSOC development. We have processed 43 specimens using highly multiplexed tissue imaging at single-cell resolution (cyclic immunofluorescence, CyCIF), and 35 specimens for micro-regional spatial transcriptomics using the GeoMx (Whole Transcriptome, Nanostring) on over 450 pathologist-annotated regions of interest. Results: Our data suggests an immune-cold environment and T-cell dysfunction in STIC lesions, including incidental STIC. One of the significant immune populations identified was CD103+ tissue-resident memory T cells (TRM). In incidental p53 signatures, activation of TRM was rare, similar to FT, which may indicate the absence of sensing “tumor antigen” by these TRM. CyCIF analysis also revealed that most incidental STIC lesions (7/9 cases) overexpress major histocompatibility complex (MHC) class I compared to the normal epithelium, especially both HLA complex, HLA-A and HLA-E. Most STICs showed extensive intra-lesion heterogeneity, with some STICs remaining HLA-A and HLA-E negative. Incidental p53 signatures, on the other hand, were mostly HLA-A and HLA-E negative and, when positive, had only a few cells expressing HLA. We hypothesized that there might be a natural selection of HLA-E-positive clones as STICs progress to HGSOC. Consistent with this, HGSOC showed further overexpression of HLA-E. However, HLA-E heterogeneity was still observed in the invasive tumor, with both positive and negative clones co-existing. Geomx data suggested that the interferon signaling pathway is upregulated in the epithelial of HLA-E positive STIC and cancer clones compared to HLA-E negative clones. In turn, both HLA-A and HLA-E might be overexpressed in the epithelial of HLA-E-positive STICs. Overall, we showed that the response in interferon (IFN) α and γ, NF-KB, and IL-6-induced STAT-3 pathways were upregulated in both STIC lesions and carcinoma. The role of these pathways, especially STAT-3 pathway, has been shown in other aneuploid cancers in promoting immune escape, cell proliferation and migration, chemoresistance and inhibiting apoptosis. We have shown the co-localization of cGAS and BAF, a marker for micronuclei rupture, by super-resolution 3D imaging to confirm one of the mechanisms of IFN activation. Conclusion: Taken together, these data may indicate chromosomal instability is one of the mechanisms that is driving the IFN-signaling pathway and, hence, a potential selective advantage for HLA-E-positive clones in tumorigenesis, leading to inhibiting NK cell surveillance followed by reducing T cell infiltration. Citation Format: Tanjina Kader, Jia-Ren Lin, Shannon Coy, Clemens Hug, Yu-An Chen, Roxanne J. Pelletier, Mariana Leon, John Lee, Yi-Lin Xu, Clarence Yapp, Natalie Shih, Gabriel Mingo, Euihye Jung, Srishti Rathore, Judith Agudo, Charles Drescher, Peter K. Sorger, Ronny Drapkin, Sandro Santagata. Multimodal spatial profiling reveals the emergence of an immune suppressive microenvironment at the initial stages of high-grade serous ovarian cancer development [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB311.

MATN2 overexpression suppresses tumor growth in ovarian cancer via PTEN/PI3K/AKT pathway.

The incidence rate of developing ovarian cancer decreases over the years; however, mortality ranks top among malignancies of women, mainly metastasis through local invasion. Matrilin-2 (MATN2) is a member of the matrilin family that plays an important role in many cancers. However, its relationship with ovarian cancer remains unknown. Our study aimed to explore the function and possible mechanism of MATN2 in ovarian cancer. Human ovarian cancer tissue microarrays were used to detect the MATN2 expression in different types of ovarian cancer using immunohistochemistry (IHC). CCK-8, wound scratch healing assay, transwell assay, and flow cytometry were used to detect cell mobility. Gene and protein expression were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. MATN2 interacts with phosphatase, and the tensin homolog (PTEN) deleted on chromosome 10 was analyzed using TCGA database and co-immunoprecipitation (Co-IP). In vivo experiments were conducted using BALB/c nude mice, and tumor volume and weight were recorded. Tumor growth was determined using hematoxylin and eosin (H&E) and IHC staining. MATN2 was significantly downregulated in ovarian cancer cells. The SKOV3 and A2780 cell mobility was significantly inhibited by MATN2 overexpression, while the cell apoptosis rate was significantly increased. MATN2 overexpression decreased transplanted tumor size in vivo. These results were reversed by inhibiting MATN2. Furthermore, we found that PTEN closely interacted with MATN2 using bioinformatics and Co-IP. MATN2 overexpression significantly inhibited the PI3K/AKT pathway, however, PTEN suppression reversed this effect of MATN2 overexpression. These results indicated that MATN2 may play a critical role in ovarian cancer development by inhibiting cells proliferation and migration. The mechanism was related to interacting with PTEN, thus inhibiting downstream effectors in the PI3K/AKT pathway, which may be a novel target for treating ovarian cancer.

Exploring the Relationship between Ovarian Cancer and Genital Microbiota: A Systematic Review and Meta-Analysis

Ovarian cancer (OC) remains a significant health challenge globally, with high mortality rates despite advancements in treatment. Emerging research suggests a potential link between OC development and genital dysbiosis, implicating alterations in the microbiome composition as a contributing factor. To investigate this correlation, a meta-analysis was conducted following PRISMA and MOOSE guidelines, involving eight studies encompassing 3504 patients. Studies investigating the role of upper and inferior genital tract dysbiosis were included, with particular reference to HPV infection and/or history of pelvic inflammatory disease. The analysis revealed no significant difference in genital dysbiosis prevalence between OC patients and healthy controls. Although previous literature suggests associations between dysbiosis and gynecologic cancers, such as cervical and endometrial cancers, the findings regarding OC are inconclusive. Methodological variations and environmental factors may contribute to these discrepancies, underscoring the need for standardized methodologies and larger-scale studies. Despite the limitations, understanding the microbiome’s role in OC development holds promise for informing preventive and therapeutic strategies. A holistic approach to patient care, incorporating microbiome monitoring and personalized interventions, may offer insights into mitigating OC risk and improving treatment outcomes. Further research with robust methodologies is warranted to elucidate the complex interplay between dysbiosis and OC, potentially paving the way for novel preventive and therapeutic approaches.

Abstract 3040: Tumor-specific super-enhancer drives overexpression of EVI1 in ovarian cancer

Abstract Epithelial ovarian cancer (OC) is typically diagnosed at a late stage and, despite treatment with cytoreductive surgery and chemotherapy, 70-80% of patients relapse and eventually die due to the disease. Major challenges to improve patient outcomes are to overcome therapy resistance and to individually tailor therapy. Uncovering the molecular drivers of OC, especially in the most common subgroup high-grade serous (HGS), will help develop novel therapeutic strategies to meet these challenges. Using the Cancer Genome Atlas (TCGA) data, we observed that a locus in 3q26.2, near the EVI1 oncogene, was the most significantly amplified region in HGS OC, occurring in more than 80% of those tumors. We validated these findings in an OC dataset from the Hartwig Medical Foundation and in OC cell lines from the DepMap database. Furthermore, HGS OC had the highest mean copy number of the 3q26.2 locus co-occurring with high mean EVI1 expression among all tumor entities in the pan-cancer TCGA dataset. These EVI1 expression levels are significantly higher than in normal fallopian tube, from which HGS OC most likely arises. EVI1 overexpression promotes leukemogenesis in 3q26-rearranged acute myeloid leukemia (AML), as a result of chromosomal translocations that enable hijacking of hyperactive enhancers. Here, we hypothesize that EVI1 also plays a crucial role in OC development, but that its aberrant expression in this disease is driven by the amplification of yet undiscovered regulatory elements near EVI1. We showed that EVI1-positive OC cell lines, of which the majority are HGS, are EVI1-dependent and harbor a ~200 kb amplified region near EVI1. This region interacts with the EVI1 promoter (4C-Seq), is characterized by open chromatin (ATAC-Seq), and shows high levels of H3K27 acetylation (H3K27ac ChIP-Seq), suggesting the presence of an active enhancer. Furthermore, based upon H3K27ac signal, we identified within this region a super-enhancer of approximately 65 kb. In OC cell lines without detectable EVI1 levels or cell lines from other cancer subtypes, such as breast and colon cancer, this location had no active enhancer and did not loop to the EVI1 promoter. Altogether, these data point to the generation of a hyperactive super-enhancer driving EVI1 overexpression in OC. These findings emphasize the importance of epigenetic control in the regulation of EVI1 expression, as previously shown in 3q26-rearranged AML. Since OC tumor cell lines are strongly dependent on EVI1, interference with this super-enhancer, leading to loss of EVI1 expression, could be exploited to inhibit tumor growth. For this purpose, we generated GFP-tagged EVI1 cell line models (e.g. SKOV3), which will be used to discover small molecules to target the activity of this super-enhancer. In conclusion, we discovered a new mechanism of enhancer-mediated overexpression of the EVI1 oncogene as a molecular driver in ovarian cancer, with possible implications for therapy. Citation Format: Leonie Smeenk, Sabrina Kruse, Roger Mulet-Lazaro, Ingrid Boere, John Martens, Stefan Gröschel, Claudia Scholl, Stefan Fröhling, Ruud Delwel. Tumor-specific super-enhancer drives overexpression of EVI1 in ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3040.

Abstract 5909: Sulindac exhibits anti-proliferative effects in pre-clinical models of ovarian cancer

Abstract Objectives: Given the intricate relationship between inflammation and ovarian cancer (OC) development and progression, anti-inflammatory drugs may have potential in the prevention and treatment of OC. Sulindac exhibits potent anti-inflammatory effects through inhibition of COX1/COX2 pathways and promising anti-tumor activity in pre-clinical models of colorectal and endometrial cancer. Thus, we investigated the efficacy of sulindac as an anti-tumorigenic agent in OC pre-clinical cell and mouse models. Methods: The human OC cell lines, MES and OVCAR5, and the K18-gT121+/-;p53fl/fl;Brca1fl/fl (KpB) mouse model of high-grade serous OC were used. Cellular proliferation was assessed by MTT and colony count assays. Apoptosis was assessed using cleaved caspase 3, 8, and 9 assays. To measure cellular stress, production of reactive oxygen species was measured by DCFH-DA assay, and the JC1 assay was used to assess changes in mitochondrial membrane potential. Cellular adhesion was evaluated by laminin assay, and cellular migration was determined by wound healing assay. Western immunoblotting was used to assess the effects of sulindac on downstream targets related to cellular stress, apoptosis, cellular invasion potential, cell cycle control, and inflammation. The KpB mice were treated with sulindac (7.5 mg/kg, oral gavage, daily) or placebo for four weeks. Results: Sulindac inhibited cellular proliferation in a dose-dependent manner in the MES and OVCAR5 cells, with IC50s of 75.3 and 75.69 μM, respectively. Sulindac (100 μM) reduced colony formation by 81% in the MES cells and by 49% in the OVCAR5 cells (p&amp;lt;0.01). Treatment of MES and OVCAR5 cells with sulindac increased ROS production and decreased mitochondrial membrane potential, in a dose-dependent manner (p&amp;lt;0.01). Sulindac induced activity of cleaved caspase 3, 8, and 9, in MES and OVCAR5 cells (p&amp;lt;0.01). In addition, sulindac (100 μM) effectively decreased cellular adhesion by 31% in MES cells and by 23% in OVCAR5 cells (p&amp;lt;0.01). These results were confirmed by Western immunoblotting demonstrating that sulindac downregulated the anti-apoptotic proteins Bcl-xl and Mcl-1 and upregulated the pro-apoptotic proteins Bax and cellular stress proteins Bip, ATF-4, and PDI, in both cell lines. Sulindac downregulated expression of several epithelial-mesenchymal transition proteins in both cell lines, including beta-catenin, snail, and slug. Sulindac also downregulated expression of cell cycle proteins CDK4, CDK5, and Cyclin D1 and inflammatory protein COX-2 in both cell lines. After 4 wks of treatment, sulindac significantly inhibited tumor growth by 71% (1.89 g vs 0.54 g, p&amp;lt;0.01) in KpB mice. Conclusions: Our results find that sulindac exhibited anti-tumorigenic effects in OC cell lines and the KpB OC mouse model. Given these promising pre-clinical results, further studies on the repurposing of sulindac for the prevention and treatment of OC is warranted. Citation Format: Nikita Sinha, Shuning Chen, Jennifer Haag, Xiaochang Shen, Boer Deng, Ziyi Zhao, Chunxiao Zhou, Victoria Bae-Jump. Sulindac exhibits anti-proliferative effects in pre-clinical models of ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5909.

Abstract 6279: Estrogen signaling in low-grade serous ovarian carcinoma

Abstract High level of estrogen in the blood of women has been linked to the progression and possibly development of ovarian cancer. Almost all low-grade serous ovarian cancer (LGSOC) expresses estrogen receptor alpha (ERα protein encoded by the gene ESR1) and develops during reproductive age of women. However, recent studies suggested that a higher expression of ERα correlates with better survival. In a phase II clinical trial, hormonal therapies have been shown to be associated with a clinical benefit rate of 61% for recurrent ER-positive LGSOC patients. The study also indicated that women with recurrent LGSOC who received hormonal therapies had a significantly longer progression-free survival but not overall survival. Endocrine therapies have proven to be effective in treating breast cancer. Unfortunately, in ovarian cancer clinical trials (GOG0281 and PARAGON), these treatments have not achieved comparable results, with an objective response rate of only approximately 14%. To understand the ESR1 regulation in LGSOC, we have performed RNAseq and ChIPseq analyses of LGSOC tumor tissues. We also forced over-expression of ESR1 in LGSOC cell lines. Using RNAseq data, we aligned the sequencing reads to all the known ESR1 transcript variants. We found that ESR1 transcript variant 1, 2, 3 and X11 were the major transcripts expressed. Variants 1, 2 and 3 encode the regular 66 kDa ESR1 protein, while the X11 variant encodes a 52 kDa ESR1 protein. Both 66 kDa and 52 kDa ESR1 proteins were also detected in LGSOC tumor tissues by western blots. To further explore the function of ESR1 66kDa in LGSOC, we over-expressed ESR1 variant 1 in two LGSOC cell lines (HOC-7 and HCC5075) by transfecting with an expression plasmid. Total proteins were extracted from the mock control and transfected cells for functional proteomic analysis by reverse phase protein arrays (RPPA). From the RPPA data, overexpressing ESR1 in LGSOC cell lines suppressed DNA repair pathways but activated cell cycle and mitosis pathways. To further delineate the ESR1 DNA binding sites in LGSOC, we performed ChIPseq analysis of these tumor samples as well as two ovarian cancer cell lines that express ESR1 protein. Our results demonstrated that ESR1 regulated “cistromes” in ER positive ovarian carcinoma is very different from that in ER positive breast cancer as much less ESR1 binding sites were found in LGSOC. There are ESR1 binding sites common to both types of cancers, but we found quite a few unique ESR1 binding sites. We are trying to integrate the ChIPseq and RNAseq data and hopefully identify, for the first time, an ovarian cancer specific ERα cistrome. ER expression may not always correlate with activation of ESR1 signaling pathways, which may be one of the reasons underlying endocrine therapy resistance in ovarian cancer. The results of an integrated analyses will also give us insight on the management of ER positive LGSOC by identifying new genetic targets that may be used in combination with endocrine therapy. Citation Format: Yvonne TM Tsang, Chun Wai Oscar Ng, David Gershenson, K-Kwok wong. Estrogen signaling in low-grade serous ovarian carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6279.

Portulaca oleracea L. polysaccharide inhibits ovarian cancer via inducing ACSL4-dependent ferroptosis.

The antitumor effect of Portulaca oleracea L. polysaccharide (POL) has been demonstrated, but whether it curbs the development of ovarian cancer has not been reported. Here, we treated ovarian cancer cells with different concentrations of POL, detected cell activity by CCK-8 assay, and apoptosis rate by flow cytometry. The results showed that SKOV3 and Hey cell survival decreased with increasing POL concentration in a dose-dependent manner. POL significantly inhibited ovarian cancer cell migration and increased cell death compared with the control group. Ferroptosis inhibitors, but not apoptosis, necrosis, and autophagy inhibitors, reversed POL-induced cell death. Further studies revealed that POL promoted the accumulation of lipid reactive oxygen species (ROS), Fe2+, malondialdehyde (MDA), and decreased glutathione (GSH) production. Moreover, POL significantly increased the mortality of ovarian cancer cells. In vivo studies confirmed that POL reduced the volume and weight of tumors and increased the levels of Fe2+ and MDA in mice in vivo. Western blot assay revealed that POL increased the expression of ACSL4 in ovarian cancer cells as well as in tumors in mice in vivo. More importantly, the POL-mediated increase in lipid ROS, Fe2+, MDA, and decrease in GSH were significantly reversed after knocking down ACSL4 in ovarian cancer cells. Thus, POL can effectively inhibit ovarian cancer development, which may be achieved by increasing ACSL4-mediated ferroptosis. These results suggest that POL has the potential to be a potential drug for targeted treatment of ovarian cancer.

Cancer-associated fibroblast-secreted FGF7 as an ovarian cancer progression promoter.

Ovarian cancer (OC) is distinguished by its aggressive nature and the limited efficacy of current treatment strategies. Recent studies have emphasized the significant role of cancer-associated fibroblasts (CAFs) in OC development and progression. Employing sophisticated machine learning techniques on bulk transcriptomic datasets, we identified fibroblast growth factor 7 (FGF7), derived from CAFs, as a potential oncogenic factor. We investigated the relationship between FGF7 expression and various clinical parameters. A series of in vitro experiments were undertaken to evaluate the effect of CAFs-derived FGF7 on OC cell activities, such as proliferation, migration, and invasion. Single-cell transcriptomic analysis was also conducted to elucidate the interaction between FGF7 and its receptor. Detailed mechanistic investigations sought to clarify the pathways through which FGF7 fosters OC progression. Our findings indicate that higher FGF7 levels correlate with advanced tumor stages, increased vascular invasion, and poorer prognosis. CAFs-derived FGF7 significantly enhanced OC cell proliferation, migration, and invasion. Single-cell analysis and in vitro studies revealed that CAFs-derived FGF7 inhibits the ubiquitination and degradation of hypoxia-inducible factor 1 alpha (HIF-1α) via FGFR2 interaction. Activation of the FGF7/HIF-1α pathway resulted in the upregulation of mesenchymal markers and downregulation of epithelial markers. Importantly, in vivo treatment with neutralizing antibodies targeting CAFs-derived FGF7 substantially reduced tumor growth. Neutralizing FGF7 in the medium or inhibiting HIF-1α signaling reversed the effects of FGF7-mediated EMT, emphasizing the dependence of FGF7-mediated EMT on HIF-1α activation. These findings suggest that targeting the FGF7/HIF-1α/EMT axis may offer new therapeutic opportunities to intervene in OC progression.

Kynurenine in IDO1high cancer cell-derived extracellular vesicles promotes angiogenesis by inducing endothelial mitophagy in ovarian cancer

BackgroundMitophagy, a prominent cellular homeostasis process, has been implicated in modulating endothelial cell function. Emerging evidence suggests that extracellular vesicles (EVs) participate in intercellular communication, which could modulate tumor angiogenesis, a hallmark of ovarian cancer (OC) progression. However, the underlying mechanisms through how EVs regulate endothelial mitophagy associated with tumor angiogenesis during OC development remain obscure.MethodsThe effect of cancer cell-derived EVs on endothelial mitophagy and its correlation with tumor angiogenesis and OC development were explored by in vitro and in vivo experiments. Multi-omics integration analysis was employed to identify potential regulatory mechanisms of cancer cell-derived EVs on endothelial mitophagy, which is involved in tumor angiogenesis associated with OC development. These insights were then further corroborated through additional experiments. An orthotopic OC mouse model was constructed to assess the antiangiogenic and therapeutic potential of the Indoleamine 2,3 dioxygenase-1 (IDO1) inhibitor.ResultsCancer cell-derived EVs promoted tumor angiogenesis via the activation of endothelial mitophagy, contributing to the growth and metastasis of OC. The aberrantly high expression of IDO1 mediated abnormal tryptophan metabolism in cancer cells and promoted the secretion of l-kynurenine (L-kyn)-enriched EVs, with associated high levels of L-kyn in EVs isolated from both the tumor tissues and patient plasma in OC. EVs derived from IDO1high ovarian cancer cells elevated nicotinamide adenine dinucleotide (NAD +) levels in endothelial cells via delivering L-kyn. Besides, IDO1high ovarian cancer cell-derived EVs upregulated sirt3 expression in endothelial cells by increasing acetylation modification. These findings are crucial for promoting endothelial mitophagy correlated with tumor angiogenesis. Notably, both endothelial mitophagy and tumor angiogenesis could be suppressed by the IDO1 inhibitor in the orthotopic OC mouse model.ConclusionsTogether, our findings unveil a mechanism of mitophagy in OC angiogenesis and indicate the clinical relevance of EV enriched L-kyn as a potential biomarker for tumorigenesis and progression. Additionally, IDO1 inhibitors might become an alternative option for OC adjuvant therapy.Graphical

Tissue Inhibitor of Metalloproteinase 3: Unravelling Its Biological Function and Significance in Oncology.

Tissue inhibitor of metalloproteinases-3 (TIMP3) is vital in regulating several biological processes. TIMP3 exerts antitumour effects via matrix metalloproteinase (MMP)-dependent and MMP-independent pathways. Due to promoter methylation and miRNA binding, TIMP3 expression has been observed to decrease in various cancers. Consequently, the migration and invasion of cancer cells increases. Conflicting results have reported that expression levels of TIMP3 in primary and advanced cancers are higher than those in healthy tissues. Therefore, the role of TIMP3 in cancer biology and progression needs to be elucidated. This review provides an overview of TIMP3, from its biological function to its effects on various cancers. Moreover, gynaecological cancers are discussed in detail. TIMP3 has been associated with cervical adenocarcinoma as well as cancer development in serous ovarian cancer and breast cancer metastasis. However, the relationship between TIMP3 and endometrial cancers remains unclear. TIMP3 may be a useful biomarker for gynaecological cancers and is a potential target for future cancer therapy.

Constitutional BRCA1 and MGMT Methylation Are Significant Risk Factors for Triple-Negative Breast Cancer and High-Grade Serous Ovarian Cancer in Saudi Women.

Breast cancer (BC) and ovarian cancer (OC) are rapidly increasing in Saudi Arabia. BRCA1 and MGMT epimutations have been linked to a higher risk of these malignancies. The present research investigated the impact of these epimutations on the prevalence of BC and OC among Saudi women. DNA methylation was evaluated using methylation-specific PCR, whereas mRNA expression levels were assessed using qRT-PCR. We evaluated white blood cell (WBC)-BRCA1 methylation in 1958 Saudi women (908 BC patients, 223 OC patients, and 827 controls). MGMT methylation was determined in 1534 of the 1958 women (700 BC patients, 223 OC patients, and 611 controls). BRCA1 methylation was detected in 8.6% of the controls and 11% of the BC patients. This epimutation was linked to 13.8% of the early-onset BC patients (p = 0.003) and 20% of the triple-negative breast cancer (TNBC) patients (p = 0.0001). BRCA1 methylation was also detected in 14% of the OC patients (p = 0.011), 19.4% of patients aged <55 years (p = 0.0007), and 23.4% of high-grade serous ovarian cancer (HGSOC) patients. In contrast, the BRCA1 mutation was detected in 24% of the OC patients, 27.4% of patients aged ≥55 years, and 26.7% of the HGSOC patients. However, MGMT methylation was detected in 10% of the controls and 17.4% of the BC patients (p = 0.0003). This epimutation was linked to 26.4% of the late-onset BC patients (p = 0.0001) and 11% of the TNBC patients. MGMT methylation was also found in 15.2% of the OC patients (p = 0.034) and 19.1% of HGSOC patients (p = 0.054). Furthermore, 36% of the BRCA1-methylated patients and 34.5% of the MGMT-methylated patients had a family history of cancer, including breast and ovarian cancer. Notably, BRCA1 and MGMT mRNA levels were greater in the WBC RNA of the BC patients and cancer-free methylation carriers than in that of the OC patients. Our data indicate that BRCA1 and MGMT epimutations significantly contribute to the development of breast cancer and ovarian cancer in Saudi cancer patients. These blood-based biomarkers could help identify female patients at high risk of developing TNBC and HGSOC at an early age.

FoxO1 promotes ovarian cancer by increasing transcription and METTL14-mediated m6A modification of SMC4.

The transcription factor forkhead box protein O1 (FoxO1) is closely related to the occurrence and development of ovarian cancer (OC), however its role and molecular mechanisms remain unclear. Herein, we found that FoxO1 was highly expressed in clinical samples of OC patients and was significantly correlated with poor prognosis. FoxO1 knockdown inhibited the proliferation of OC cells invitro and invivo. ChIP-seq combined with GEPIA2 and Kaplan-Meier database analysis showed that structural maintenance of chromosome 4 (SMC4) is a downstream target of FoxO1, and FoxO1 promotes SMC4 transcription by binding to its -1400/-1390 bp promoter. The high expression of SMC4 significantly blocked the tumor inhibition effect of FoxO1 knockdown. Furtherly, FoxO1 increased SMC4 mRNA abundance by transcriptionally activating methyltransferase-like 14 (METTL14) and increasing SMC4 m6A methylation on its coding sequence region. The Cancer Genome Atlas dataset analysis confirmed a significant positive correlation between FoxO1, SMC4, and METTL14 expression in OC. In summary, this study revealed the molecular mechanisms of FoxO1 regulating SMC4 and established a clinical link between the expression of FoxO1/METTL14/SMC4 in the occurrence of OC, thus providing a potential diagnostic target and therapeutic strategy.

HIF-2α-dependent TGFBI promotes ovarian cancer chemoresistance by activating PI3K/Akt pathway to inhibit apoptosis and facilitate DNA repair process

Hypoxia-mediated chemoresistance plays a crucial role in the development of ovarian cancer (OC). However, the roles of hypoxia-related genes (HRGs) in chemoresistance and prognosis prediction and theirs underlying mechanisms remain to be further elucidated. We intended to identify and validate classifiers of hub HRGs for chemoresistance, diagnosis, prognosis as well as immune microenvironment of OC, and to explore the function of the most crucial HRG in the development of the malignant phenotypes. The RNA expression and clinical data of HRGs were systematically evaluated in OC training group. Univariate and multivariate Cox regression analysis were applied to construct hub HRGs classifiers for prognosis and diagnosis assessment. The relationship between classifiers and chemotherapy response and underlying pathways were detected by GSEA, CellMiner and CIBERSORT algorithm, respectively. OC cells were cultured under hypoxia or transfected with HIF-1α or HIF-2α plasmids, and the transcription levels of TGFBI were assessed by quantitative PCR. TGFBI was knocked down by siRNAs in OC cells, CCK8 and in vitro migration and invasion assays were performed to examine the changes in cell proliferation, motility and metastasis. The difference in TGFBI expression was examined between cisplatin-sensitive and -resistant cells, and the effects of TGFBI interference on cell apoptosis, DNA repair and key signaling molecules of cisplatin-resistant OC cells were explored. A total of 179 candidate HRGs were extracted and enrolled into univariate and multivariate Cox regression analysis. Six hub genes (TGFBI, CDKN1B, AKAP12, GPC1, TGM2 and ANGPTL4) were selected to create a HRGs prognosis classifier and four genes (TGFBI, AKAP12, GPC1 and TGM2) were selected to construct diagnosis classifiers. The HRGs prognosis classifier could precisely distinguish OC patients into high-risk and low-risk groups and estimate their clinical outcomes. Furthermore, the high-risk group had higher percentage of Macrophages M2 and exhibited higher expression of immunecheckpoints such as PD-L2. Additionally, the diagnosis classifiers could accurately distinguish OC from normal samples. TGFBI was further verified as a specific key target and demonstrated that its high expression was closely correlated with poor prognosis and chemoresistance of OC. Hypoxia upregulated the expression level of TGFBI. The hypoxia-induced factor HIF-2α but not HIF-1α could directly bind to the promoter region of TGFBI, and facilitate its transcription level. TGFBI was upregulated in cisplatin-sensitive and resistant ovarian cancer cells in a cisplatin time-dependent manner. TGFBI interference downregulated DNA repair-related markers (p-p95/NBS1, RAD51, p-DNA-PKcs, DNA Ligase IV and Artemis), apoptosis-related marker (BCL2) and PI3K/Akt pathway-related markers (PI3K-p110 and p-Akt) in cisplatin-resistant OC cells. In summary, the HRGs prognosis risk classifier could be served as a predictor for OC prognosis and efficacy evaluation. TGFBI, upregulated by HIF-2α as an HRG, promoted OC chemoresistance through activating PI3K/Akt pathway to reduce apoptosis and enhance DNA damage repair pathway.

Angio-Long Noncoding RNA MALAT1 (rs3200401) and MIAT (rs1061540) Gene Variants in Ovarian Cancer.

The genotyping of long non-coding RNA (lncRNA)-related single-nucleotide polymorphisms (SNPs) could be associated with cancer risk and/or progression. This study aimed to analyze the angiogenesis-related lncRNAs MALAT1 (rs3200401) and MIAT (rs1061540) variants in patients with ovarian cancer (OC) using "Real-Time allelic discrimination polymerase chain reaction" in 182 formalin-fixed paraffin-embedded (FFPE) samples of benign, borderline, and primary malignant ovarian tissues. Differences in the genotype frequencies between low-grade ovarian epithelial tumors (benign/borderline) and malignant tumors and between high-grade malignant epithelial tumors and malignant epithelial tumors other than high-grade serous carcinomas were compared. Odds ratios (ORs)/95% confidence intervals were calculated as measures of the association strength. Additionally, associations of the genotypes with the available pathological data were analyzed. The heterozygosity of MALAT1 rs3200401 was the most common genotype (47.8%), followed by C/C (36.3%). Comparing the study groups, no significant differences were observed regarding this variant. In contrast, the malignant epithelial tumors had a higher frequency of the MIAT rs1061540 C/C genotype compared to the low-grade epithelial tumor cohorts (56.7% vs. 37.6, p = 0.031). The same genotype was significantly higher in high-grade serous carcinoma than its counterparts (69.4% vs. 43.8%, p = 0.038). Multivariate Cox regression analysis showed that the age at diagnosis was significantly associated with the risk of OC development. In contrast, the MIAT T/T genotype was associated with a low risk of malignant epithelial tumors under the homozygote comparison model (OR = 0.37 (0.16-0.83), p = 0.017). Also, MIAT T allele carriers were less likely to develop high-grade serous carcinoma under heterozygote (CT vs. CC; OR = 0.33 (0.12-0.88), p = 0.027) and homozygote (TT vs. CC; OR = 0.26 (0.07-0.90), p = 0.034) comparison models. In conclusion, our data provide novel evidence for a potential association between the lncRNA MIAT rs1061540 and the malignant condition of ovarian cancer, suggesting the involvement of such lncRNAs in OC development.

LRP8 promotes tumorigenesis in ovarian cancer through inhibiting p53 signaling.

Ovarian cancer (OC) is the most lethal gynecological malignancy with a high mortality rate. Low-density lipoprotein (LDL) receptor-related protein 8 (LRP8) is a cell membrane receptor belonging LDL receptor family and is involved in several tumor progressions. However, there is limited understanding of how LRP8 mediates OC development. LRP8 expression level was identified in human OC tissues and cells using immunohistochemical staining and quantitative polymerase chain reaction assays, respectively. Functions of LRP8 in OC progression were evaluated by Celigo cell counting, wound healing, transwell and flow cytometry assays, and the xenograft models. The human phospho-kinase array analysis was used for screening potential signaling involved in OC development. We observed that LRP8 was overexpressed in OC tissues, and high expression of LRP8 was associated with poor prognosis of OC patients. Functionally, LRP8 knockdown remarkably reduced proliferation and migration of OC cells, and induced apoptosis and S phase cycle arrest. LRP8 deficiency attenuated in vivo tumor growth of OC cells. Moreover, the addition of p53 inhibitor partially reversed the effects of LRP8 knockdown on OC cell proliferation and apoptosis, indicating the involvement of p53 signaling in LRP8-mediated OC progression. This study confirmed that LRP8/p53 axis contributed to OC progression, which might serve as a novel potential therapeutic target for OC patients.

Exploring the causal role of multiple metabolites on ovarian cancer: a two sample Mendelian randomization study

BackgroundThe mechanisms and risk factors underlying ovarian cancer (OC) remain under investigation, making the identification of new prognostic biomarkers and improved predictive factors critically important. Recently, circulating metabolites have shown potential in predicting survival outcomes and may be associated with the pathogenesis of OC. However, research into their genetic determinants is limited, and there are some inadequacies in understanding the distinct subtypes of OC. In this context, we conducted a Mendelian randomization study aiming to provide evidence for the relationship between genetically determined metabolites (GDMs) and the risk of OC and its subtypes.MethodsIn this study, we consolidated genetic statistical data of GDMs with OC and its subtypes through a genome-wide association study (GWAS) and conducted a two-sample Mendelian randomization (MR) analysis. The inverse variance weighted (IVW) method served as the primary approach, with MR-Egger and weighted median methods employed for cross-validation to determine whether a causal relationship exists between the metabolites and OC risk. Moreover, a range of sensitivity analyses were conducted to validate the robustness of the results. MR-Egger intercept, and Cochran’s Q statistical analysis were used to evaluate possible heterogeneity and pleiotropy. False discovery rate (FDR) correction was applied to validate the findings. We also conducted a reverse MR analysis to validate whether the observed blood metabolite levels were influenced by OC risk. Additionally, metabolic pathway analysis was carried out using the MetaboAnalyst 5.0 software.ResultsIn MR analysis, we discovered 18 suggestive causal associations involving 14 known metabolites, 8 metabolites as potential risk factors, and 6 as potential cancer risk reducers. In addition, three significant pathways, "caffeine metabolism," "arginine biosynthesis," and "citrate cycle (TCA cycle)" were associated with the development of mucinous ovarian cancer (MOC). The pathways "caffeine metabolism" and "alpha-linolenic acid metabolism" were associated with the onset of endometrioid ovarian cancer (OCED).ConclusionsOur MR analysis revealed both protective and risk-associated metabolites, providing insights into the potential causal relationships between GDMs and the metabolic pathways related to OC and its subtypes. The metabolites that drive OC could be potential candidates for biomarkers.

Clinicopathological features and clinical outcomes in individuals with Krukenberg tumors of colorectal origin.

191 Background: Krukenberg tumors (KT) are metastases to the ovary generally originating from a gastrointestinal primary such as colorectal carcinoma. The prognosis is poor with KT, and clinicopathological features associated with clinical outcomes have not been extensively studied. The study aimed to investigate the associations of clinicopathological features with outcomes in patients with KT of colorectal carcinoma (CRC) origin. Methods: This retrospective study utilized medical records and patient registries to identify 160 patients with a confirmed histopathological diagnosis of KT at Stanford University Medical Center between 2000 and 2020. Data collection included demographics, historical, clinicopathological, treatment and outcome variables. The primary tumor type was (N, %): CRC (101, 63.1%); gastric (24, 15%), breast (13, 8.1%); small bowel (10, 6.2%), other (12, 7.5%). Statistical analysis was performed using Chi-squared, Mann-Whitney U, and log-rank Kaplan-Meier analysis. Results: Analysis of the CRC cohort subdivided by location of the primary, N: 45 vs. 56, right colon (R) vs. left colon (L) revealed no significant difference in median age at diagnosis of KT, race/ethnicity, oligometastatic disease, histopathological differentiation or ovarian tumor volume. Patients with R vs L sided CRC primaries had a higher proportion of synchronous presentation at the time of KT diagnosis (75.6% vs 41.1%, R vs L, p&lt;0.001). Time to progression was not different, but overall survival (OS) was shorter in R CRC (767 vs. 1246 days, R vs. L, p &lt;0.01). By Kaplan-Meier analysis, patients with R CRC had a shorter OS (log-rank p=0.016). In the subgroup with unilateral KT, R sided CRC primaries involved the R ovary (85%) whereas L-sided CRC primaries involved the L ovary (70%) ( χ2, p&lt;0.002). Patient with bilateral (B) versus unilateral (U) had a larger ovarian tumor volume (2,073cm3 vs. 307 cm3, p&lt;0.01) but no difference in oligometastatic disease, chronicity, time to progression or overall survival. There was no statistical difference (p=0.93) between the association of bilateral KT inter-ovarian tumor size and CRC Laterality within individual patients. Conclusions: In this study, KT tumors predominantly originate from CRC. The clinical features of R versus L CRC, such as chronicity and OS are conveyed prognostically in patients with KT. Individuals with L CRC exhibited a better overall prognosis compared to those with R CRC. In patients with unilateral KT metastasis to ipsilateral ovary is significantly associated with location of CRC and is suggestive of a retrograde lymphatic or transcoelomic route of metastatic spread. Further studies are needed to confirm these findings and to elucidate ovarian organ tropism mediators that facilitate development and growth in metastatic ovarian cancer.

Agricultural exposure and risk of ovarian cancer in the AGRIculture and CANcer (AGRICAN) cohort

BackgroundOvarian cancer is rare with a poor prognosis and few established risk factors. Hormones and reproductive factors significantly impact its development, suggesting a potential link with endocrine disrupters.MethodsIn the AGRICAN...