PER2 and cancer: In Per2–/– livers, however, we observed upregulation of genes involved in autophagy (Ulk1, Plk3, Sesn2), circadian regulation (Ngfr, Klf10, Atf5), and inhibition of cell proliferation (Ngfr, Hes1, Tob1) following cancer cell injection (Figure 4C and cluster 1 and Supplementary Table 2).