CCNG2 (cyclin G2) is a cell cycle regulatory protein that functions primarily as a negative regulator of cell cycle progression. It localizes predominantly to the cytoplasm 1 and acts as a cyclin-dependent kinase regulator, controlling G1/S transition of the mitotic cell cycle. Despite structural similarity to cyclin G1, CCNG2 performs distinct functions 1. Mechanistically, CCNG2 suppresses proliferation through G0/G1 phase arrest and inhibits CDK2 expression 2. Its expression is regulated by the AKT pathway; AKT inhibition increases CCNG2 expression, which subsequently promotes apoptosis and reduces proliferation 3. CCNG2 expression is also regulated post-transcriptionally by microRNAs including miR-1290, miR-1246, and miR-302b 456. Clinically, CCNG2 acts as a tumor suppressor across multiple cancers. Reduced CCNG2 expression correlates with higher pathological grade, poor prognosis, and increased metastatic potential in colorectal carcinoma, astrocytomas, oral squamous cell carcinoma, and pancreatic cancer 2345. In prostate cancer, CCNG2 mediates androgen-induced cellular senescence through the AR-BHLHE40-CCNG2 axis 7. Additionally, CCNG2 expression in visceral adipose tissue inversely associates with insulin resistance and glucose levels 8, suggesting metabolic regulatory roles beyond cancer.