miRNA expression profiling of the A375 melanoma cell line and its dabrafenib-resistant A375R sub-line.

Altered expression of miRNAs has been demonstrated in tumor tissue and plasma/serum of cancer patients. miRNAs have been shown to have both diagnostic and prognostic significance and to potentially constitute novel targets and therapeutic agents for cancer treatment. Experimental evidences also support a role of miRNAs in tumor cell response to therapy, including resistance to BRAF inhibitors (BRAFi) in melanoma. In this study, miRNA expression pattern was determined in a BRAFV600E melanoma cell line sensitive to the BRAFi dabrafenib (i.e A375) and in its drug-resistant counterpart (i.e. A375R), derived in vitro by culturing the sensitive cell line with progressively increasing concentrations of dabrafenib (from 8 nM to 1.5 mM). Total RNA was extracted from the melanoma cell line A375 and its dabrafenib-resistant sub-line A375R, and miRNA expression pattern was determined using Affymetrix GeneChip® miRNA 3.1 microarrays.