High Expression of Ubiquitin-Specific Protease 39 and Its Roles in Prognosis in Patients with Hepatocellular Carcinoma

BACKGROUND: Ubiquitin-specific protease 39 is mainly involved in mRNA splicing and multiple kinds of tumors. Accumulating evidence has shown that USP39 participated in the proliferation and metastasis of hepatocellular carcinoma (HCC). The present study aimed to demonstrate the association between USP39 expression and clinical features and the diagnostic value in HCC based on the Cancer Genome Atlas (TCGA). METHODS: A comprehensive analysis for expression of USP39 in HCC was conducted by using multiple databases. The mRNA level of USP39, clinical features, survival rate, and diagnostic value in HCC were analyzed using data from TCGA. The Gene Set Enrichment Analysis (GSEA) was conducted to analyze signaling pathways correlated with USP39 expression in HCC. RESULTS: The mRNA level of USP39 was significantly elevated in HCC. The expression of USP39 showed significant correlation with T stage, pathologic stage, tumor status, age, and histologic grade. Logistic analysis demonstrated that high expression of USP39 was significantly associated with older age, tumor status, advanced pathologic stage, T stage, and higher histologic grade. Univariate Cox regression analysis showed that high expression of USP39 was significantly associated with advanced T stage, pathological stage, and tumor status. Multivariate Cox analysis confirmed the result that USP39 expression was an independent prognostic factor for overall survival (OS) in HCC. Results of Kaplan–Meier curves showed that high expression of USP39 had a significant association with poor OS, disease-free survival (DSS), and progress-free interval (PFI) in HCC. ROC analysis indicated that USP39 could be regarded as a promising marker for distinguishing HCC from nontumor. CONCLUSION: The increased USP39 might play roles in the progression, diagnosis, and prognosis of HCC.