Aberrant microRNA-182 expression is associated with glucocorticoid resistance in lymphoblastic malignancies

Abstract

Glucocorticoid (GC) resistance in lymphoblastic malignancies is related to treatment failure and is a marker of poor prognosis. Previous studies have suggested that microRNA-182 (miR-182) functions as an oncogene and plays a role in tumorigenesis, through regulation of FOXO3A. FOXO3A has been implicated in tumor suppression and GC-induced apoptosis, suggesting that FOXO3A has potential as a therapeutic target. Herein we investigated the role of miR-182 in GC sensitivity in lymphoblastic malignancies. Expression of miR-182 was consistently higher in human and mouse GC-resistant cell lines than in GC-sensitive cell lines. Furthermore, increased expression of miR-182 reduced total FOXO3A expression but had no significant effect on phospho-FOXO3A. Additionally Bim, as a downstream target of FOXO3A, was reduced by overexpression of miR-182, and increased by down-regulation of miR-182. These results demonstrate that miR-182 is involved in glucocorticoid resistance, via targeting of FOXO3A, and that restoration of miR-182 is a potentially promising therapeutic strategy in lymphoblastic malignancies.

Keywords::

• Lymphoblastic malignancies
• glucocorticoid resistance
• MIR182
• FOXO3A
• BIM

Acknowledgements

We thank J.M., W.Q., Y.S. and B.Z. for their technical assistance.

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.