Figure 1. A cancer network commonly described as the Rb-E2F network.

This is a network of oncogenes (red boxes) and tumor suppressor genes (white boxes) involved in the regulation of the Restriction Point¹⁰,⁴⁴,⁴⁵,⁴⁶. The dashed arrow lines indicate transcriptional activation while solid hammer lines indicate inhibition. pRB, retinoblastoma protein; E2F, family of transcription factors consisting of E2F1, E2F2 and E2F3; p16, cyclin-dependent kinase inhibitor 2A; p27, cyclin-dependent kinase inhibitor 1B; cyclin D/Cdk4, 6: complex formed by cyclin D, Cdk4 and Cdk6; Cdk2/Cyclin E: complex formed by cyclin E and Cdk2; CdC25A, cell division cycle 25 homolog A.