Up-regulated expression of phospholipase C, β1 is associated with tumor cell proliferation and poor prognosis in hepatocellular carcinoma

Background: Phospholipase C, beta 1 (PLCB1) plays critical roles in intracellular transduction and regulating signal activation which are important to tumorigenesis. However, the mechanism of PLCB1 in hepatocellular carcinoma (HCC) is still unknown. This study aims to investigate whether its expression is associated with the clinicopathological parameters and prognosis of the patients with HCC. Methods: Immunohistochemistry on two tissue microarrays containing 141 cases of HCC tissues and adjacent non-tumorous tissues were performed to analyze the correlation between PLCB1 expression and clinicopathological features. Kaplan-Meier analysis and Cox multivariate analysis were performed to determine the PLCB1 expression in HCC prognosis. Furthermore, effects of PLCB1 on proliferation of HCC cells were explored using a colony formation assay and apoptosis assay. Results: We identified that PLCB1 expression was significantly higher in tumor tissues than that in adjacent non-tumorous tissues and associated with advanced tumor stage. Kaplan-Meier survival analysis showed that patients with PLCB1-positive tumors had poorer survival than the patients with PLCB1-negative tumors. In multivariate analyses, PLCB1 expression was an independent prognostic factor. Moreover, overexpression of PLCB1 in HCC cells promoted cell proliferation and inhibited apoptosis, while knocking down PLCB1 reduced cell viability in vitro. Further investigation found that activation of ERK signaling might involve in PLCB1-mediated cell growth. Conclusion: Our study suggests that PLCB1 promotes the progression of HCC and can be served as an independent prognostic factor and a promising therapeutic target in HCC.