In hepatocellular carcinoma (HCC) cells, post-translational activation of cystathionine -synthase (CBS) under TNF-induced oxidative stress increases TSS activity through a proteolytically cleaved and highly active form of CBS, increasing cystathionine and GSH production (102), which in turn promotes tumor progression and inhibits ferroptosis. The gene discussed is CBS; the disease is hepatocellular carcinoma.