Elevated CTSL2 expression is associated with an adverse prognosis in hepatocellular carcinoma

Cathepsin V, also known as CTSL2, plays an important role in tumor development and progression. This study was designed to investigate the clinical significance of CTSL2 expression in hepatocellular carcinoma (HCC) and the relationship between CTSL2 expression and prognosis.

Quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry (IHC) were performed to determine the levels of CTSL2 mRNA and protein, respectively, in tumor tissue and matched non-tumor (NT) tissue. Moreover, the relationship between CTSL2 expression and hepatocellular carcinoma's clinicopathological features and survival was evaluated in HCC tissue.

The levels of CTSL2 mRNA and protein were increased in HCC tissue. Moreover, for HCC patients, a high level of CTSL2 protein was significantly correlated with tumor number (P = 0.008), pathological grade (P = 0.001), vascular invasion (P = 0.001), T (P = 0.001), and TNM stage (P = 0.006). A Kaplan-Meier analysis showed that elevated CTSL2 expression was correlated with shorter disease-free survival (DFS) (P < 0.001) and overall survival (OS) (P < 0.001). Furthermore, a multivariate analysis showed that CTSL2 expression was an independent prognostic factor for DFS (P = 0.032) and OS (P = 0.025).

This study showed that abnormal CTSL2 expression may contribute to HCC progression and that elevated CTSL2 expression is associated with an adverse prognosis in HCC.