PER2 and cancer: We further found that additional core clock genes that are part of the repressive arm were increased in WT KPC but not FoxP1SkmKO KPC mice, including Per2, Per3, Nr1d2, and Bhlhe41. The identification of FOXP1 as a modulator of these core clock genes in response to cancer is of potential significance, as disruptions to the clock may perturb normal time-of-day-dependent oscillations in rhythmically expressed genes that are critical for muscle homeostasis.