Abstract: Expression of hClock and hBmal1 in TumorsXiangqun DENG1, Pengfei ZHANG2, Yinni HE3Correspondence to: Xiangqun DENG, E-mail: dengxiangqun01@163.com1Department of Histology and Embryology, Shaoyang Medical College, Shaoyang 422000, China2Intensive Laboratory of Tumor Proteomics, Xiangya Hospital, Central South University, Changsha 410008, China3Department of Phylaxiology, Shaoyang Medical College, Shaoyang 422000, ChinaAbstract Objective: To study the human circadian clock genes hClock and hBmal1, as well as their significance in the develop-ment and progression of tumors. Methods: Immunohistochemical detection of colorectal tumors and adjacent tissues, as well as expres-sion of the lung cancer tissue hClock gene protein product ( CLOCK protein ) was conducted. In situ hybridization detection of sampleshBmal1 and hClock gene mRNA expressions was carried out. Results: In lung cancer, moderately and strongly positive CLOCK pro-tein expression is positively correlated with the degree of differentiation. In benign colorectal tumors, CLOCK protein has a moderatelyto strongly positive expression of 25.0% ( 2/8 ). In malignant tumors, it has moderately and strongly positive expression rate of 86.5% (32/37). In colorectal malignant tumors, hClock mRNA has a moderately and strongly positive expression rate of 75.7% ( 28/37 ). Themoderately and strongly positive hClock mRNA expression is positively correlated with Dukes stage. Up to 37 cases of moderatecolorectal malignant tumors were positive for hBmal1 mRNA, with a strongly positive rate of 43.2% ( 16/37 ). The hBmal1 mRNA ex-pression is positively correlated with Dukes stage. Conclusion: The hClock and hBmal1 genes are correlated with the occurrence of tu-mors, development and invasion, and metastasis.Keywords hClock gene; hBmal1 gene; Tumor