LAUSR

Breast cancer is the most deadly cancer among women and the second leading cause of cancer death worldwide. Treatment effectiveness is complicated with tumor invasiveness/drug resistance. To tailor treatments more effectively to individual patients, it is important to define tumor growth and metastasis at molecular levels. SDCBP is highly overexpressed and associated with a strikingly poor prognosis in breast cancer. However the post transcriptional regulation of SDCBP overexpression remains to be an unexplored area. Our study reveals that miR-216b directly regulates SDCBP expression by binding to its 3'UTR region. miR-216b is a tumor suppressive miRNA and it is underexpressed during metastatic breast cancer. Consequently, overexpression of miR-216b resulted in decreased proliferation, migration and invasion in BC cell lines by modulating the expression of SDCBP. Inhibition of miR-216b divergent the tumor suppressive role by inducing the growth proliferation, migration and invasion in vitro. There is therefore a negative correlation between the expression of miR-216b and its target gene SDCBP in the BC tissue samples as well as cell lines. Simultaneous expression of miR-216b and SDCBP rescued the growth, migration and invasion effect suggesting that tumor suppressive action of miR-216b may be directly mediated by SDCBP. In summary, the study identifies miR-216b as a regulator of SDCBP expression in breast cancer which can potentially be targeted for developing newer therapies for the effective treatment of this killer disease.