Abstract :
Period1 (PER1) is an important core clock gene, which regulates normal cell proliferations and physiological rhythms of human beings. Recent studies have showed aberrant expressions and altered rhythms of PER1 were highly correlated to the carcinogenesis and development of malignant tumors. However, there is no study on the correlation of aberrant expressions and altered rhythms of PER1 with the growth, proliferation and metastasis of buccal squamous cell carcinoma (BSCC). In this study, PER1 and MMP-2 expression in the cancerous and adjacent noncancerous tissues of 38 patients with BSCC and its correlations with patients' clinical pathologic characteristics were investigated. A mouse model of BSCC was also established and mice were sacrificed at 4 different time points in a period of 24 hours. Xenografted tumor weight, proliferation index (PI), and mitotic index (MI) of tumors in the 4 time groups were detected. Results showed that PER1 expression was significantly down-regulated in cancerous tissues of patients with BSCC (P