ADP-ribosylation factor-like 4C predicts worse prognosis in endometriosis-associated ovarian cancers

BACKGROUND: Endometrioid ovarian carcinoma and clear cell ovarian carcinoma are both classified as endometriosis-associated ovarian cancer (EAOC). Despite the high rates of recurrence and mortality of EAOC, no prognostic biomarkers have been determined. ADP-ribosylation factor-like protein 4C (ARL4C) has been reported to be involved in various tumor progression processes, but its clinical significance for predicting prognosis in EAOC cases has never been studied. OBJECTIVE: The present study aimed to determine the clinical significance of ARL4C expression in EAOC prognosis. METHODS: ARL4C expression was semi-quantitatively evaluated via immunohistochemistry in 61 EAOC patients, and the correlations between ARL4C expression and clinicopathological data and survival were statistically analyzed. RESULTS: Thirty-six (59%) cases had high levels of ARL4C, which was related to worse 5-year overall survival (OS) (log-rank test, p = 0.036). In multivariate Cox proportional hazard model, high ARL4C expression was a significantly independent predictive factor for worse 5-year OS (hazard ratio = 12.048, p = 0.0201) and 5-year PFS (hazard ratio = 8.130, p = 0.0036). CONCLUSIONS: ARL4C is a biomarker for worse prognosis and a novel therapeutic target in EAOC.