Increased expression of autophagy-related gene 5 indicates poor prognosis in patients with hepatocellular carcinoma.

ABSTRACT

OBJECTIVES: As a critical component of the autophagic machinery, autophagy-related gene 5 (ATG5) is essential for autophagosome formation. Autophagy participates in the transformation and progression of various malignant tumors, but the role of ATG5 in hepatocellular carcinoma (HCC) remains to be illustrated. In this study we aimed to investigate the prognostic significance of ATG5 in HCC. METHODS: ATG5 expression was evaluated in 89 pairs of HCC tissues and adjacent non-tumor tissues. The relationship between ATG5 expression and patients' clinicopathological characteristics and prognosis were evaluated. Moreover, subgroup analyses were performed regarding patients' age and number of tumors. Nomograms estimating overall survival (OS) and disease-free survival (DFS) were conducted. RESULTS: ATG5 expression was increased in HCC specimens rather than adjacent non-tumor tissues. The upregulated ATG5 expression was positively associated with serum α-fetoprotein (AFP) level. Moreover, cases with a strong ATG5 expression had a poorer disease-free survival (DFS) and overall survival (OS) than those with a weak ATG5 expression. Multivariate analysis showed that a strong expression of ATG5 was related to a poor OS and DFS in patients with HCC. Further analysis indicated that cases with a higher ATG5 expression had a poorer OS and DFS in the young patients (≤55 years) and those with solitary tumor. The nomogram suggested that there was a coherence between nomogram prediction and the actual situation of patient survival related to ATG5. CONCLUSION: ATG5 promotes tumor progression in HCC, making it a potential biomarker in the diagnosis and a therapeutic target of HCC.