Molecular pathways involved in microRNA-mediated regulation of multidrug resistance.

Multidrug resistance (MDR) is still a major reason for therapeutic failure in cancers. The mechanisms underlying MDR are multifactorial and are not fully understood. miRNAs are evolutionarily conserved non-coding RNAs that function as key post-transcriptional regulators of gene expression. Emerging evidence indicates a vital role of miRNAs in the resistance to cancer treatments and suggests their potential for cancer therapy, as they can modulate multiple mechanisms link to the development of MDR. This review summarizes the recent findings on the role of miRNAs in MDR, and highlights the molecular targets and mechanisms of miRNA regulated pathways in MDR. Finally, the challenges and prospects of miRNA-targeted therapies for reversing drug resistance are reviewed.