[Clinical significance of RYBP expression in primary hepatocellular carcinoma]

To explore the clinical significance of the altered expression of polycomb group (PcG)-associated protein RYBP in hepatocellular carcinoma (HCC) specimens. Methods: The expression levels of RYBP in tumor tissues and adjacent normal tissues in 77 HCC cases were detected by immunohistochemistry (IHC), and the relationships between RYBP expression levels and HCC clinicopathological characteristics, five-year survival rates or prognosis of HCC patients were analyzed. Results: RYBP expression level was significantly decreased in HCC tumor tissues than that in the adjacent normal tissues (P<0.05). The expression levels of RYBP in HCC specimens were highly correlated with HBsAg, ALT, GGT, Type III procollagen, tumor size, distant metastasis, and tumor differentiation (P<0.05). The RFS and OS for patients with RYBP-low expression were markedly lower than those with RYPB-high expression (P<0.05). Both age and RYBP expression level were protective factors for RFS, while GGT, lymph node metastasis, TNM stage, tumor differentiation and tumor size were risk factors for RFS (P<0.05). As to OS, RYBP expression level was a protective factor, while tumor number, ALT, GGT, AFP, pCEA, lymph node metastasis, TNM stage, tumor differentiation and tumor size were risk factors (P<0.05). The age, GGT, lymph node metastasis and TNM stage were independent prognostic factors for RFS (P<0.05), and both lymph node metastasis and TNM stage were independent risk factors for OS (P<0.05). Comparing to serum alpha fetoprotein (AFP) level, RYBP expression level in tumor tissues was applied to predict the prognosis of HCC patients more accurately. Conclusion: PcG associated protein RYBP displays a reduced expression in HCC tissues, which is related to poor prognosis of HCC patients. It might be a promising therapeutic target for HCC treatment.