Stigmast-4-en-6-ol-3-one decreases viability and induces apoptosis and ferroptosis in liver cancer cells by reducing E2F1

Hepatocellular carcinoma (HCC) is a frequently occurring malignant gastrointestinal cancer. The 5-year survival rate of HCC is still below 8%, and thus, identifying more effective therapeutic methods is needed. Here, we evaluated the effects of Stigmast-4-en-6 beta-ol-3-one (S463) on the viability and colony formation of liver cancer cells. S463 treatment decreased the viability and induced apoptosis and ferroptosis in liver cancer cells, and also increased cellular malondialdehyde (MDA) and lipid peroxidation levels. In S463 treated cells, the expression level of Bax was increased, and the expression level of GPX4 was reduced, and the cleavage of PARP was improved. We also found that S463 treatment downregulated E2F1 and upregulated p53 at both the mRNA and protein levels. Importantly, rescue experiments revealed that overexpression of E2F1 partially restored S463-induced Bax and p53 upregulation and GPX4 downregulation and counteracted the S463-induced decrease in cell viability and colony formation and the S463-induced increase in MDA and lipid peroxidation levels. Our findings suggest that S463 significantly inhibits viability and colony formation and induces apoptosis and ferroptosis in liver cancer cells via E2F1.