Notably, cells with constitutively activated STAT3 display heightened levels of cyclin D1, a protein that drives cell cycle progression from G1 to S phase, contributing to uncontrolled cell proliferation in HCC.35,62 Moreover, STAT3 exerts pro-angiogenic effects in HCC by regulating the expression of various pro-angiogenic factors within the tumor microenvironment (TME). The gene discussed is CCND1; the disease is hepatocellular carcinoma.