Ontology highlight
ABSTRACT: Purpose
The onset of drug resistance is a major cause of treatment failure in multiple myeloma. Although increasing evidence is defining the role of miRNAs in mediating drug resistance, their potential activity as drug-sensitizing agents has not yet been investigated in multiple myeloma.Experimental design
Here we studied the potential utility of miR-221/222 inhibition in sensitizing refractory multiple myeloma cells to melphalan.Results
miR-221/222 expression inversely correlated with melphalan sensitivity of multiple myeloma cells. Inhibition of miR-221/222 overcame melphalan resistance and triggered apoptosis of multiple myeloma cells in vitro, in the presence or absence of human bone marrow (BM) stromal cells. Decreased multiple myeloma cell growth induced by inhibition of miR-221/222 plus melphalan was associated with a marked upregulation of pro-apoptotic BBC3/PUMA protein, a miR-221/222 target, as well as with modulation of drug influx-efflux transporters SLC7A5/LAT1 and the ABC transporter ABCC1/MRP1. Finally, in vivo treatment of SCID/NOD mice bearing human melphalan-refractory multiple myeloma xenografts with systemic locked nucleic acid (LNA) inhibitors of miR-221 (LNA-i-miR-221) plus melphalan overcame drug resistance, evidenced by growth inhibition with significant antitumor effects together with modulation of PUMA and ABCC1 in tumors retrieved from treated mice.Conclusions
Taken together, our findings provide the proof of concept that LNA-i-miR-221 can reverse melphalan resistance in preclinical models of multiple myeloma, providing the framework for clinical trials to overcome drug resistance, and improve patient outcome in multiple myeloma.
SUBMITTER: Gulla A
PROVIDER: S-EPMC4775414 | biostudies-literature | 2016 Mar
REPOSITORIES: biostudies-literature
Gullà Annamaria A Di Martino Maria Teresa MT Gallo Cantafio Maria Eugenia ME Morelli Eugenio E Amodio Nicola N Botta Cirino C Pitari Maria Rita MR Lio Santo Giovanni SG Britti Domenico D Stamato Maria Angelica MA Hideshima Teru T Munshi Nikhil C NC Anderson Kenneth C KC Tagliaferri Pierosandro P Tassone Pierfrancesco P
Clinical cancer research : an official journal of the American Association for Cancer Research 20151102 5
<h4>Purpose</h4>The onset of drug resistance is a major cause of treatment failure in multiple myeloma. Although increasing evidence is defining the role of miRNAs in mediating drug resistance, their potential activity as drug-sensitizing agents has not yet been investigated in multiple myeloma.<h4>Experimental design</h4>Here we studied the potential utility of miR-221/222 inhibition in sensitizing refractory multiple myeloma cells to melphalan.<h4>Results</h4>miR-221/222 expression inversely c ...[more]