Silencing of mcl-1 and bcl-2 by mir-15 induces apoptosis and increases the chemosensitivity of the cll cells

Razie Amini,1,* Nooshin ashofteh,2 Hadi karami,3 Leila koushki,4

1. Department of Molecular Medicine and Biotechnology, Faculty of Medicine, Arak University of Medical Sciences
2. Department of Molecular Medicine and Biotechnology, Faculty of Medicine, Arak University of Medical Sciences
3. Department of Molecular Medicine and Biotechnology, Faculty of Medicine, Arak University of Medical Sciences
4. Department of Molecular Medicine and Biotechnology, Faculty of Medicine, Arak University of Medical Sciences

Abstract

Introduction

Despite advances in cancer therapy, drug resistance is a major problem in leukemia. overexpression of anti-apoptotic proteins, bcl-2 and mcl-1, is associated with drug resistance in numerous tumors including chronic lymphoid leukemia (cll). also, previous reports have demonstrated that mir-15 can directly target bcl-2 and mcl-1. in this study the effects of mir-15 on the sensitivity of the cll cells to fludarabine and abt-199 was explored.

Methods

The cytotoxic effects of fludarabine and abt-199, alone or in combination with mir-15, on cll-cii cell line were evaluated using mtt test. relative bcl-2 and mcl-1mrna expression levels were measured using qrt-pcr. elisa cell death assay was applied for measurement of apoptosis. trypan blue assay was used to assess cancer cell growth.

Results

Transfection of mirna-15 significantly reduced the mrna expression level of mcl-1 and bcl-2, leading to strong growth inhibition of cll cells. moreover, knocking down of mcl-1 and bcl-2 by mirna-15 increased apoptosis and enhanced the cytotoxic effects of fludarabine and abt-199.

Conclusion

Our result indicates that suppression of mcl-1 and bcl-2 by mirna-15 augments the sensitivity of the leukemia cell to fludarabine and abt-199.therefore; mirna-15 may be a potent adjuvant in cll therapy.

Keywords

Mir-15, fludarabine, abt-199, mcl-1, bcl2, cll