Associated analysis of PER1/TUBB2B with endometrial cancer development caused by circadian rhythm disorders

Endometrial cancer (EC) is one of the most common gynecologic malignancies, and the incidence rate of night shift among women workers is higher than that in the general population. Circadian rhythm disorder, mainly rhythm gene, is related to various tumor onset, including EC. This study described the sleep/night-shift features of EC patients, explored the mechanism of the circadian clock gene PER and investigated prognostic and functional values of Per1 caused by night shift. A total of 619 subjects were enrolled and divided into two groups according to night-shift duties (rhythm group and control group), analyzed for clinical risk factors and night shift features of endometrial carcinoma. Then samples were randomly selected for sequencing and western blot were performed, and the function of overexpressed PER1 in ishikawa cells was explored. We noticed that severer EC patients experienced night-shift more frequently and with longer durations. A total of 58,174 differentially expressed genes were discovered, mainly rhythm genes and related to up and downstream regulatory genes. Western blot showed that the rhythm group had elevated protein expression of BCAS4, TUBB2B and RSPO4, and decreased expression of PER1 and PER2 in night-shift. In TCGA-EC datasets, PER1 was decreased in the EC patients with a significantly positive correlation with PER2, and higher PER1 expression indicated longer survival, opposite to TUBB2B. The research of overexpressing PER1 gene in EC ishikawa cells found that PER1 can promote apoptosis, expression of TNF-a, IL-6 and PD-1/PD-L1, inhibit the tumor invasion and expression of TUBB2B gene. Together, EC severity was associated with night-shift and rhythm disorders. The rhythm relating factors PER1, TUBB2B and tumor immune factors may regulate the mechanisms of EC onset and progression.