Progression of squamous cell carcinoma is regulated by miR-139-5p/CXCR4.

miR-139-5p has a tumor suppressor effect in some cancers and negatively regulates CXCR4. To this end, we examined the expression and mechanism of of action of miR-139-5p and CXCR4 in oral squamous cell carcinoma (OSCC). miRNA-139-5p was down-regulated whereas CXCR4 was increased in tissues and cells of OSCC. Moreover, low expression of miR-139-5p was associated with a low survival. Overexpression of miR-139-5p in OSCC inhibited in vitro and in vivo cell proliferation and in vitro mobility of OSCC and inhibited the expression of WNT responsive c-myc, cyclinD1, and Bcl-2, and such effects were all reversible by an inhibitor of miR-139-5p or over-expression of CXCR4. The inverse relation between expression of miR-139-5p and CXCR4 might be related to the fact that miR-139-5p negatively regulates CXCR4 expression by virtue of direct binding. These findings underscore the importance of miR-139-5p and CXCR4 in regulation of OSCC.