KRAS and progeroid syndrome: While normal aging (Figure 2D,E, Supplementary Materials Figures S3 and S4) appears to affect the cell cycle G2/M checkpoint (G2M checkpoint), E2F targets, and the mitotic spindle assembly (hallmark MITOTIC_SPINDLE), progeria is only associated with KRAS signaling up, the genes upregulated by KRAS (Kristen rat sarcoma virus) activation (Figure 1D,E, Supplementary Materials Figures S1 and S2).