TITLE:
Doxorubicin Induces Apoptosis through down Regulation of miR-21 Expression and Increases miR-21 Target Gene Expression in MCF-7 Breast Cancer Cells
AUTHORS:
Roghayeh Tofigh, Saeedeh Akhavan, Nastaran Tarban, Amin Ebrahimi Sadrabadi, Arsalan Jalili, Kaykhosro Moridi, Sara Tutunchi
KEYWORDS:
miR-21, mcf-7 Cells, Caspase 9, Cancer
JOURNAL NAME:
International Journal of Clinical Medicine,
Vol.8 No.6,
June
23,
2017
ABSTRACT: miRNAs play an important regulatory role in variety of cellular functions and several diseases, including cancer. MicroRNA-21 (miR-21) is overexpressed in almost all types of human cancers. Studies revealed that the knockdown of miR-21 results in reduced tumor cell growth, cell cycle arrest and cell apoptosis. In this study, we evaluated the effect of doxorubicin on miR-21 expression in mcf-7 breast cancer cells. miRNA was extracted from mcf-7 cells treated with doxorubicin and untreated cells using miRNeasy Kit (Qiagen) according to the manufacturer’s instructions. cDNA synthesis was performed using miScript II RT Kit (Qiagen) and Real Time-PCR was performed using Real Q Plus 2x Master Mix Green-(Ampliqon, Denmark). The relative expression of miR-16 and miR-21 was calculated using comparative Ct method. All tests were run in triplicate to minimize the experimental errors. Samples with a Ct > 37 were excluded from the analysis. Statistically, a significant decrease in cell proliferation of mcf-7 cells was found in doxorubicin group compared with control groups 24 hours after transfection, dose dependently (p value