Fig 2: (A) The expression levels of PER1 in breast cancer cells were increased by trichostatin A (TSA) and MA2 treatment. (B) Immunofluorescence staining showed that TSA treatment markedly enhanced fluorescence intensity of PER1 expression in both MDA-MB-231 and BT-549 cells. (C) The expression of PER1 protein induced by TSA was further elevated by proteasome inhibitor MG132.

Fig 3: Angptl8 knockdown dampens the liver clock reset by food. Mice were transduced with AAVs carrying either Angptl8 shRNA or scramble shRNA for 45 days. a Serum Angptl8 levels in mice subjected to 12-h food deprivation (ZT13-1) or 12-h food deprivation followed by 20 min refeeding. n = 5, **P < 0.01 Refed vs. Fasted mice, ##P < 0.01 AAV-Angpptl8 shRNA vs. AAV-scramble shRNA, one-way ANOVA followed by Bonferroni’s post hoc test. b, c qPCR analyses of Per1 and Per2 mRNA expression in the liver of mice from a. n = 5, **P < 0.01 Refed vs. Fasted mice. ##P < 0.01 AAV-Angpptl8 shRNA vs. AAV-scramble shRNA, one-way ANOVA followed by Bonferroni’s post hoc test. d A schematic diagram illustrating the time design of DD and a fasting/refeeding cycle for liver-specific Angptl8 knockdown mice. e, f Time-course mRNA and serum levels of Angptl8 in mice subjected to 7-day DD and fasted for 12 h at CT13 or12-h food deprivation followed by refeeding for 21 h. g qPCR analyses of clock genes. h Serum levels of certain metabolites. For e–h n = 3, *P < 0.05 and **P < 0.01 refed vs. fasted mice. #P < 0.05 and ##P < 0.01 AAV-Angpptl8 shRNA vs. AAV-scramble shRNA, two-way ANOVA followed by Bonferroni’s post hoc test. All data are presented as the means ± SD. Source data are provided as a Source Data file

Fig 4: (A) The alteration of PER1 mRNA expression in various human cancers was analyzed using the Oncomine database. (B) The expression level of PER1 was downregulated in most of human cancers. (C) The expression of PER1 mRNA was significantly lower in breast cancer tissues than in adjacent non-cancer tissues. (D) The expression of PER1 was decreased in paired breast cancer samples. *P<0.05, **P<0.01, and ***P<0.001.

Fig 5: (A) Kaplan–Meier curves showed that high expression of PER1 was significantly correlated to better overall survival (OS) and recurrence-free survival (RFS). (B) The multivariate Cox regression analysis revealed that low expression of PER1 was an independent predictor of poor survival for breast cancer patients.