Cyclin-dependent kinase inhibitor 2B gene is associated with the sensitivity of hepatoma cells to Sorafenib

Purpose: The sensitivity of advanced hepatocellular carcinoma (HCC) to Sorafenib is low. The purpose of this study was to investigate the effects of cyclin-dependent kinase inhibitor 2B (CDKN2B) gene on the prognosis of HCC and the sensitivity of HCC cells to Sorafenib. Patients and methods: Streptavidin-perosidase (SP) staining was performed to determine the expression of CDKN2B in HCC tissues and adjacent tissues. The cell counting kit-8 (CCK-8) assay was carried out to determine cell viability. CDKN2B mRNA and protein were tested by real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot, respectively. CDKN2B gene was silenced or over-expressed in the cells by plasmid transfection technique. Flow cytometry was carried out to detect cell cycle and apoptosis. Results: SP staining results showed that CDKN2B was positive in adjacent tissues and in HCC tissues from partial response (PR) patients, CDKN2B was slightly positive in stable disease (SD) patients, but negative in progression disease (PD) patients. The survival rate of patients with low expression of CDKN2B was low. Up-regulation of CDKN2B expression could promote the pro-apoptotic effect of Sorafenib and cell arrest in G1 phase. When the CDKN2B gene expression was down-regulated, the cell apoptosis rate and the proportion of cells treated with Sorafenib in G1 phase decreased. Silencing CDKN2B reversed CDKN2B overexpression caused by Sorafenib. Conclusion: CDKN2B genes were lowly expressed in tumor tissues from HCC patients who were treated with Sorafenib and had a poor prognosis. Up-regulation of CDKN2B promoted sensitivity of HCC to Sorafenib, and similarly down-regulation of CDKN2B reduced the sensitivity.