The Efficacy of Combined Therapy of Regorafenib with Detoxicating and Stasis Softening Chinese Herbal Spleen Tonics in Mid-/Late-Stage Hepatocellular Carcinoma

OBJECTIVE: To explore the efficacy of combined therapy of Regorafenib with detoxicating and stasis softening Chinese herbal spleen tonics (DSS-splenic tonics) in mid-/late-stage hepatocellular carcinoma. METHODS: Retrospective observational data of 120 patients were obtained, 60 of which received combined therapy of DSS-splenic tonics and regorafenib. Adverse event, overall survival (OS), and time-to-progress (TTP) were analyzed. Synergistic effect of DSS-spleen tonics was found and validated in human hepatocellular carcinoma HCCLM3 cell line and xenograft mouse models. RESULTS: Combination of regorafenib and DSS-splenic tonics also slightly extended the TTP and OS compared with treatment of regorafenib alone, suggesting DSS-splenic tonics has synergistic effect with regorafenib. Both Regorafenib and DSS-spleen tonics exerted inhibitory effect on cell viability and invasion capability of HCCLM3 cells, and combining both could enhance the antitumor effect. At molecular level, we found that VEGF, HIF-1α, MVD, and VEGF2 were all suppressed by regorafenib and DSS-splenic tonics. These results suggest that DSS-spleen tonics function synergistically with regorafenib in HCC by enhancing the regulation of regorafenib on VEGF, MMP-2, HIF-1α, and MVD, and may diminish angiogenesis during HCC progression. CONCLUSION: DSS-spleen tonics could exert synergistic antitumor effect with regorafenib via targeting VEGF.