OSR1 downregulation indicates an unfavorable prognosis and activates the NF-κB pathway in ovarian cancer.

BACKGROUND

Odd-skipped related 1 (OSR1) has been reported as a tumor suppressor gene in various malignant tumors. The mechanism through which OSR1 regulates ovarian cancer (OC) progression remains unclear.

MATERIALS AND METHODS

Immunohistochemistry was utilized to evaluate OSR1 expression in patients with ovarian cancer. We investigated the association between clinicopathological parameters and OSR1 expression in OC patients and the influence of OSR1 expression on patient survival and prognosis. OC cells with OSR1 overexpression or knockdown were established and validated using Western blot and Quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The influence of OSR1 on the NF-κB pathway was examined by analyzing the p-IκBα, IκBα, p65, and p-p65 protein expression. In vitro assays, such as cell cycle assay, Cell Counting Kit-8 (CCK-8), transwell invasion assay, wound healing migration assay, enzyme-linked immunoassay (ELISA), and Annexin V/PI flow cytometry apoptosis assay, were conducted to explore the effect of OSR1 knockdown or dual inhibition of OSR1 and the NF-κB pathway on OC malignant biological behavior.

RESULTS

OSR1 expression was downregulated in OC tissues, with significant associations observed between its expression and The International Federation of Gynecology and Obstetrics (FIGO) stage and tissue differentiation. Low OSR1 expression in OC patients correlated with reduced overall survival (OS) rates and poor prognosis. In vitro, experiments confirmed a negative correlation between OSR1 expression and NF-κB pathway activity. OSR1 knockdown facilitated OC cell malignant biological behavior, while the NF-κB pathway inhibitor (Bay 11-0782) reversed the impacts of OSR1 knockdown on cell proliferation, migration, invasion, and apoptosis.

CONCLUSION

Our findings indicate that OSR1 is downregulated and associated with OC prognosis. OSR1 suppresses NF-κB pathway activity and inhibits OC progression by targeting the NF-κB pathway.