Downregulation of MED23 promoted the tumorigenecity of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is one of the most common tumors in the world. It is very urgent to develop new therapeutic strategies. MED23, a component of the mediator complex, is known as a hub to integrate various signaling pathways. However, the function of MED23 in ESCC remains unknown. Here, we found that the expression of MED23 was downregulated in the clinical ESCC samples and the expression of MED23 reversely correlated with tumor size and clinical stage. Moreover, overexpression of MED23 in ESCC cells inhibited cell growth dramatically, while downregulation of MED23 promoted the tumorigenecity of ESCC cells in vitro and in vivo. Mechanistically, knockdown the expression of MED23 inhibited cell apoptosis by downregulation of Bax, activated Caspase 3, activated Caspase 9 and upregulation of cyclinD1 and Bcl2. Taken together, our study revealed the suppressive role of MED23 in ESCC and MED23 might be an important therapeutic target in ESCC. © 2013 Wiley Periodicals, Inc.

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