Yindan Pinggan Capsule Suppresses Hepatocellular Carcinoma Proliferation via TGR5-mediated Dual Inhibition of YAP and Hedgehog Pathways

INTRODUCTION: Hepatocellular Carcinoma (HCC) remains a highly lethal malignancy with limited therapeutic options, particularly in advanced stages. Yindan Pinggan Capsule (YDPG), a Traditional Chinese Medicine (TCM) formulation with hepatoprotective properties, has shown potential in liver diseases; however, its anti-tumor effects against HCC and the underlying mechanisms remain unclear. This study aimed to evaluate the anti-tumor effects of YDPG against HCC, elucidate its molecular mechanisms, and investigate its potential synergistic effects with Sorafenib. METHODS: Network pharmacology was performed to predict potential targets and pathways of YDPG against HCC. Anti-tumor effects were evaluated in vitro using CCK-8, colony formation, and flow cytometry assays, and in vivo using subcutaneous allograft, orthotopic liver tumor, and Diethylnitrosamine (DEN)/ carbon tetrachloride (CCl4)-induced HCC mouse models. RNA sequencing, RT-qPCR, Western blot, immunofluorescence, mass spectrometry, and agonist treatment assays were conducted to elucidate the underlying mechanisms. RESULTS: Network pharmacology analysis identified cell cycle-related pathways and proliferation-associated genes, including Ccnd1 and Myc, as potential targets of YDPG. YDPG markedly inhibited HCC cell proliferation and induced G1/S phase arrest in vitro, and significantly suppressed tumor growth in mouse models in vivo. Mechanistically, YDPG activated G protein-coupled bile acid receptor 1 (TGR5), thereby inhibiting YAP nuclear translocation and suppressing Gli1 expression, ultimately downregulating the downstream oncogenic regulators c-Myc and Cyclin D1. Notably, YDPG exhibited synergistic anti-tumor effects with low-dose Sorafenib, achieving comparable efficacy to that of high-dose Sorafenib alone. DISCUSSION: By activating TGR5 and inhibiting YAP and Hedgehog pathways, YDPG functions as a multitargeting agent with a distinct mechanism from conventional HCC therapies. Its synergy with low-dose Sorafenib offers a potential strategy to reduce targeted therapy-related toxicity without compromising efficacy, supporting the integration of mechanistically characterized TCM into conventional HCC treatment. CONCLUSION: These findings demonstrate that YDPG suppresses HCC progression through activation of TGR5 and simultaneous inhibition of the YAP and Hedgehog signaling pathways. Moreover, YDPG enhances the anti-tumor efficacy of Sorafenib, highlighting its translational potential as an adjuvant therapeutic strategy for HCC.