Sorafenib promotes hepatocellular carcinoma invasion via interleukin-6/HIF-1α/PFKFB3

Background: Although sorafenib is adopted as the first-line treatment for unresectable liver cancer, the antitumor efficacy is severely limited by the pro-invasive side effect. Methods: To explore the underlying mechanisms, various-dosage sorafenib was applied to survey its effect on cell invasion in HCCLM3 and PLC cell models. Results: Our results revealed that high-dosage sorafenib inhibited liver cancer cell invasion. By contrast, sorafenib with low and median dosages promoted the invasion. In vivo studies showed that sorafenib with a median dosage increased the intrahepatic metastasis (IHM) and lung metastasis (LM) of liver cancer cells, while sorafenib with a high dosage inhibited IHM and LM. Then, bioinformatics analysis indicated that HIF-1α, IL-6, and PFKFB3 were associated with the sorafenib resistance. In vitro models showed that the pro-invasive effect was mediated by IL-6/HIF-1α/PFKFB3 regulation in dosage- and time-dependent manners. PFKFB3 knockdown confirmed that PFKFB3 promoted HCCLM3 cell migration via modulating EMT-related markers. Furthermore, we found that sorafenib upregulated PFKFB3 by IL-6/HIF-1α in a time-dependent manner, without direct effect on PFKFB3 expression. Conclusions: In summary, these results demonstrated that sorafenib could dose-dependently promote cell invasion, intrahepatic and lung metastasis in hepatocellular carcinoma through IL-6/HIF-1α mediated PFKFB3 activation, providing novel insights to improve the therapeutic efficacy of sorafenib.