Low Expression of CyclinH and Cyclin-Dependent Kinase 7 Can Decrease the Proliferation of Human Esophageal Squamous Cell Carcinoma

Increased expression of cyclinH (CCNH) and cyclin-dependent kinase 7 (CDK7) has a relationship with poor prognosis in most human cancers. Investigate the expression of CCNH and CDK7 in human esophageal squamous cell carcinoma (ESCC) and the effect of chemotherapy on their expression. Western blotting and immunohistochemistry were used to measure the expression of CCNH and CDK7 proteins in ESCC and adjacent normal tissue in 98 patients. We use Cell Counting Kit-8 and cell flow to analyze the effects of cisplatin and interference of CCNH and CDK7 in cell cycle process. Immunohistochemical analysis showed that CCNH and CDK7 expression were significantly associated with unfavorable clinicopathologic variables. CCNH and CDK7 protein levels were elevated in ESCC tissues in comparison with adjacent normal tissues. Survival analysis revealed that CCNH and CDK7 overexpression were significantly associated with overall survival (P < 0.001). Cisplatin or interference of CCNH or CDK7 led cells to grow slowly. Overexpression of CCNH and CDK7 in TE1 cells can lead to resistance to cisplatin. We can conclude that CCNH and CDK7 may play an important role in the tumorigenesis and development of ESCC. CCNH and CDK7 expression affected the chemotherapy of tumor.