Skip to main content
. 2021 May 13;11(5):407. doi: 10.3390/jpm11050407

Figure 1.

Figure 1

Regulation of the cell cycle in HR+/HER2- mBC patients. The regulation of the cell cycle is mediated by the CCND1–CDK4/6-RB axis. The CCND1–CDK4/6 complex phosphorylates the RB protein, which releases E2F transcription factors. The latter lead to the G1/S transition of the cell cycle. The cyclin–CDK complexes are, in turn, regulated by other cyclins or intrinsic CDK inhibitors (INK4 and CIP/KIP family members) (in red). The current treatments in HR + mBC are endocrine therapy (in purple) and CDK inhibitors (in green). (HR: hormone receptor, HER2: human epithelial growth factor receptor 2, CCND1: cyclin D1, CDK4/6: cyclin-dependent kinase 4/6, RB: retinoblastoma, E2F: E2F transcription factor, CDK inhibitors: cyclin-dependent kinase inhibitors, INK4: inhibitors of CDK4, CIP/KIP: CDK interacting protein/kinase inhibitory protein).