Abstract
Sorafenib has been recommended as a new palliative therapy for advanced hepatocellular carcinoma (HCC). However, the sensitivity of HCC cells to sorafenib is declined along with the extension of medication time, and the clinical outcome varies with patients receiving sorafenib therapy. Therefore, in the present study, we attempted to investigate the effect and mechanisms of IL-6 on sensitivity of HCC cells to sorafenib regarding the cell proliferation and apoptosis. Tissues from patients with HCC and its paracarcinoma tissues were collected for IL-6 expression determination. SiRNA (si) IL-6 was transfected into SMMC-7721 cells to evaluate the effects of IL-6 on cell sensitivity to sorafenib by RT-PCR, western blot, CCK-8 and flow cytometry assay. Results indicated that IL-6 was significantly upregulated in tumor tissues than that of paracarcinoma tissues. Furthermore, sorafenib significantly inhibited cell proliferation, IL-6 level and activation of p-PI3K/AKT while promoted the cell apoptosis rate and Caspase3 level compared as the control group, which were further promoted by administration of si IL-6. Therefore, downregulating IL-6 could be a potential treatment to increase the cell sensitivity of HCC cells to sorafenib.