Prolyl-4-Hydroxylase α Subunit 2 as a Novel Potential Biomarker for Predicting the Prognosis of Epithelial Ovarian Carcinoma

OBJECTIVE: Epithelial ovarian cancer (EOC) is one of the leading causes of death worldwide. The aim of this study was to explore the prognostic significance of prolyl-4-hydroxylase α subunit 2 (P4HA2) in patients with EOC. PATIENTS AND METHODS: A total of 217 clinical samples (EOC tissues, 167 cases; normal ovarian, 50 cases) were collected and pathologically confirmed using hematoxylin and eosin (H&E) staining. P4HA2 expression in clinical samples was stained by immunohistochemistry (IHC). Relationship between P4HA2 expression and clinicopathological characteristics of EOC patients were analyzed using chi-square test. The differential expression of targets was analyzed in Oncomine database. The prognostic value of P4HA2 was investigated in clinical EOC patients and Kaplan–Meier (KM) Plotter database. RESULTS: IHC staining showed that P4HA2 was significantly up-regulated in EOC tissues, compared to the normal tissues. Two databases retrieved from Oncomine database further confirmed the up-regulation P4HA2 in EOC. Chi-square test demonstrated that P4HA2 expression was associated with clinical stage (p=0.036), tumor grade (p<0.001), and residual disease (p=0.022). Both in clinical samples and KM Plotter database, high P4HA2 expression was significantly associated with worse progression-free survival (PFS) and overall survival (OS). Cox’s proportional hazards regression analysis suggested that high P4HA2 expression were independent risk factors for the survival of EOC patients. Besides, we confirmed the positive correlation between P4HA2 and COL1A1 expression. Moreover, COL1A1 was found to be up-regulated in EOC and also associated with short PFS and OS. CONCLUSION: The present study preliminarily proved that P4HA2 expression was associated with clinical outcome in EOC patients. P4HA2 might be a prognostic factor for EOC progression, and has the potential to be a valuable therapeutic target for EOC.