RRM2 and cancer: CR-activated cell cycle periodic genes in our study are directly or indirectly involved in tumorigenesis pathways, drive cancer cell proliferation, and aggressiveness (RRM2, ACSL3, RBBP8, KMO, FKBP5), drug resistance (ABCC5), and modulate chemosensitivity (FKBP5) (references in Table S2A).