Shugan Paidu Decoction promotes cuproptosis of hepatoma cells by downregulating STAT3 levels

Objective Shugan Paidu Decoction (SGPDT) is a traditional Chinese medicine (TCM) formula clinically used to treat Wilson's disease. Through network pharmacology analysis, we predicted that SGPDT might also be effective in treating liver cancer. However, the active compounds in SGPDT and their underlying mechanisms remain unknown. This study aimed to elucidate the molecular mechanisms by which SGPDT exerts the therapeutic effects on liver cancer. Methods The correlation between SGPDT and liver cancer was analyzed using network pharmacology based on publicly available databases. The inhibitory effects of SGPDT on in vitro cell proliferation and migration were validated using CCK-8, colony formation, wound healing, and transwell assays. Intracellular copper ion concentrations were measured, and the mRNA levels of cuproptosis-related genes (CRGs) were assessed by RT-qPCR. The roles of STAT3 in SGPDT-induced cuproptosis were further investigated by evaluating the effects of STAT3 depletion on copper ion concentrations, the levels of key cuproptosis-associated protein DLAT and the mRNA of CRGs. Results Network pharmacology analysis identified STAT3 as one of the top genes associated with SGPDT's anti-liver cancer effects. SGPDT inhibited the proliferation and migration of liver cancer cells but did not show a significant impact on normal liver cells. SGPDT induced liver cancer cell death by downregulating STAT3 levels. Furthermore, SGPDT decreased STAT3 levels and induced cuproptosis by elevating intracellular copper ion concentrations. Knockdown of STAT3 altered cellular copper metabolism and induced cuproptosis in liver cancer cells, while overexpression of STAT3 reduced drug sensitivity to SGPDT in hepatocellular carcinoma (HCC) cells. Conclusion SGPDT induces cuproptosis by downregulating STAT3 levels, highlighting its inhibitory effect on hepatocellular carcinoma cell proliferation and migration, as well as its potential therapeutic value for liver cancer.