Project description:To identify highly expressed circular RNAs (circRNAs) in OCCC and elucidate their function, we performed a circRNA microarray analysis using two OCCC clinical samples and their corresponding normal ovarian tissues from the opposite side, screening 13,617 circRNAs.
Project description:To identify genes critical for the proliferation of ovarian clear cell carcinoma (OCCC), we performed CRISPR/CAS9 screens against the OCCC cell lines OVICE, ES2, TOV21G and JHOC5 using the TKOv3 sgRNA library.
Project description:Endometriosis, a benign inflammatory disease whereby endometrial-like tissue grows outside the uterus, is a risk factor for endometriosis-associated ovarian cancers. In particular, ovarian endometriomas, cystic lesions of deeply invasive endometriosis, are considered the precursor lesion for ovarian clear-cell carcinoma (OCCC). To explore the transcriptomic landscape, OCCC from women with pathology-proven concurrent endometriosis (n = 4) were compared to benign endometriomas (n = 4) by bulk RNA and small-RNA sequencing.
Project description:To investigate the microRNA profiles of ovarian clear cell carcinoma (OCCC), microRNA sequencing was performed using formalin-fixed, paraffin-embedded (FFPE) and fresh-frozen clinical samples. Moreover, patient-derived xenograft (PDX) tumors and cell lines were also investigated.
Project description:Ovarian clear cell carcinoma (OCCC) is an epithelial ovarian cancer (EOC) histology having distinct pathology, biology, and molecular footprints. OCCC is chemo-resistant and has the worst stage-adjusted prognosis amongst EOC. Yet, treatment for OCCC patients is no different than other EOC. As OCCC incidence rate has significantly increase in recent decades, it is critical to find OCCC-tailored therapeutic. However, majority of EOC gene expression molecular subtypes (GEMS) studies for personalized medicine focused on the high grade serous histology, and studies in OCCC GEMS were of small sample size. Using more than 200 OCCC gene expression profiles, we identified two OCCC subtypes: EpiCC—epithelial-like, early stage, good prognosis, relative higher rate of gene mutations in SWI/SNF complex; and MesCC—mesenchymal-like, late stage, and poor prognosis. The differential prognosis between EpiCC and MesCC could be observed as early as stage IC. Genetic, copy number and transcriptome profiling showed that both EpiCC and MesCC carried OCCC-associated aberrations. The EpiCC and MesCC are reproducible in validation cohorts and OCCC cell lines. Cell lines assays showed that MesCC is more proliferative and more anoikis resistant than EpiCC. Both EpiCC and MesCC are resistant to cisplatin. Applying the OCCC subtypes to TCGA 534 renal clear cell carcinoma indicated interoperability of the subtyping scheme, and revealed preferential response of EpiCC to sorafenib, and MesCC to bevacizumab. The EpiCC and MesCC classification shows promise in prognostication utility especially for stage IC OCCC patients, and warrants further investigation for subtype-tailored treatment regimen.
Project description:Ovarian clear cell carcinoma (OCCC) is a cancer of unmet need characterized by ARID1A mutation. Prior work identified an ARID1A/ATR synthetic lethality, information that led to phase II clinical trials. Using genome-wide CRISPR-Cas9 mutagenesis and interference screens, we identified protein phosphatase 2A (PP2A) subunits, including PPP2R1A, as determinants of ATRi sensitivity in ARID1A mutant OCCC. Analysis of an OCCCs cohort indicated that >1/3 possessed both PPP2R1A and ARID1A loss-of-function mutations. CRISPR-prime editing demonstrated that oncogenic PPP2R1A p.R183 missense mutations enhance in vitro and in vivo ATRi sensitivity in ARID1A mutant OCCC. OCCC patients with both ARID1A and PPP2R1A mutations also showed clinical responses to ATRi in a phase II trial. Mechanistically, this synthetic lethal effect is dependent upon WNK1 kinase, which opposes PP2A function. This data suggests that co-occurrence of PPP2R1A and ARID1A mutations in OCCC should be assessed as a biomarker of ATRi response in on-going clinical trials.
Project description:Ovarian cancer (OC) is a highly fatal and refractory malignancy affecting women, with platinum resistance remaining a major clinical dilemma. Ovarian clear cell carcinoma (OCCC) frequently exhibits increased platinum refractoriness than the other OC subtypes, accompanied by heightened glycogen that engenders clear-cell morphology and wild-type p53. However, their roles in platinum resistance are unclear. Here, we investigated whether glycogen promotes OCCC platinum resistance, and found that GYS1 as a rate-limiting enzyme in glycogen synthesis is clinically associated with poor prognosis and chemoresistance in OCCC. GYS1 is a rate-limiting enzyme in glycogen synthesis, which is clinically associated with poor prognosis and chemoresistance in OCCC. Mechanistically, p53 promotes GYS1 breakdown via upregulating RNF144a, while GYS1 enhances reversed ubiquitination and degradation toward p53 by competitively bound to the USP14, forming a positive feedback circuit. Under platinum stress the accumulated glycogen is mobilized by p53/GYS1 feedback circuit, which fueling energetic NADPH production, hence gaining disulfidptosis invulnerability and increased platinum resistance in OCCC. Collectively, our study identifies glycogen as a contributor to OCCC platinum resistance and elucidates the underlying mechanisms, highlighting a crucial p53/GYS1 positive feedback loop.
Project description:Ovarian clear cell carcinoma (OCCC) is the most lethal gynecological cancer. It is characterized by somatic inactivating mutations of ARID1A, a component of the SWI/SNF chromatin-remodeling complex, occurring in up to 70% of patients. Patients with these mutations in their tumors have considerably poorer outcomes compared to those without such mutations. ARID1A-deficient cells have been shown to have a higher dependence on mitochondrial respiration, suggesting that targeting mitochondrial respiration is a promising approach to eliminating ARID1A-deficient cancer cells. Here we generated and characterized OCCC-derived ARID1A wild type and knock-out cell lines. Our proteomic data provide evidence of the increased relative abundance of mETC proteins in the ARID1A knock-out OCCC cells. Taken together, our data provides a rationale for identifying therapeutic vulnerabilities within the mETC in the context of treating ARID1A-deficient OCCC.