Modulates the activity of cell cycle-specific kinases. Enhances CDK1 activity. May contribute to the regulation of the cell cycle. May inhibit growth of glioma cells by promoting arrest of mitotic progression at the G2/M transition. Fibrogenic factor contributing to the pathogenesis of renal fibrosis through fibroblast activation. {ECO:0000269|PubMed:11687586, ECO:0000269|PubMed:17146433, ECO:0000269|PubMed:19158077, ECO:0000269|PubMed:22163048}. This is the function of Ensembl gene identifier ENSG00000102760 (RGCC, regulator of cell cycle).