Roya Aliasgari - MSc of genetics, Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran,
somayeh Reiisi - Assistance professor, Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Irans,

Background and Aim: miRNAs are small noncoding RNA with ۲۰-۲۵nt in length that known to be aberrantly expressed in various diseases, including cancer. MiR-۴۵۱۶ dysregulation was observed in various cancers; its overexpression has been reported in papillary thyroid and prostate cancer. In addition, reduced miR-۴۵۱۶ expression inhibits tumor growth and induces apoptosis in glioblastoma. Unlike the other cancers, still there is no information available on mir-۴۵۱۶ in breast cancer. Therefore, in this study we evaluated miR-۴۵۱۶ expression and association with clinopathological factors in breast cancer.Methods: in this study ۳۵ paraffin-embedded breast cancer tumor tissues with adjacent healthy tissue were enrolled. The total RNA was extracted with MN kit (NucleoSpin® totalRNA FFPE- Germany). The miRNA cDNA was synthesized in polyadenylation method. Real-Time PCR was used to investigate miR-۴۵۱۶ expression. U۶ was selected as internal reference gene for normalization of real-time RT-PCR. Relative gene expression was analyzed by the ۲−ΔΔCt method. Eventually we analyzed data using statistical methods including t-test and one-way ANOVA.Results: According to the analysis, miR-۴۵۱۶ expression was significantly downregulated in tumor tissues compared to adjacent nontumor tissues (P = ۰.۰۰۱). In addition significant decrease in expression of miR-۴۵۱۶ was observed in grade ۲ tumors (P = ۰.۰۰۳).Conclusion: Taken together, these findings indicate that miR-۴۵۱۶ may act as tumor suppressor in breast cancer. In addition, miR-۴۵۱۶ expression is associated with high grade of breast cancer.

miR-۴۵۱۶, breast cancer, expression, high grade