MicroRNA-139-5p modulates the growth and metastasis of malignant melanoma cells via the PI3K/AKT signaling pathway by binding to IGF1R.

The relation between microRNAs (miRNAs) and malignant melanoma has been demonstrated in previous studies, while there was little research about miR-139-5p and malignant melanoma. The aim of this study is to investigate the ability of miR-139-5p in malignant melanoma cells via the modulation of the PI3K/AKT signaling pathway by targeting IGF1R. MiR-139-5p expression in malignant melanoma tissues and 5 malignant melanoma cell lines was detected. The melanoma cells were transfected with miR-139-5p mimic negative control (NC) sequence, miR-139-5p mimic, IGF1R overexpressed recombinant plasmid NC or IGF1R overexpressed sequence. The expression of Akt signaling pathway-related protein was evaluated. The biological functions in malignant melanoma cells were evaluated by a string of experiments. MiR-139-5p expressed a poor level in tissues and cell lines of malignant melanoma. Overexpressed miR-139-5p suppressed the cell proliferation, migration, and invasion, and contributed to the promoted apoptosis of malignant melanoma cells by decreasing IGF1R. MiR-139-5p down-regulated the IGF1R expression, and IGF1R accelerated the activation of the PI3K/AKT signaling pathway. miR-139-5p reversed the promotive impacts of IGF1R on the PI3K/AKT signaling pathway. The study validates that miR-139-5p could suppress malignant melanoma progression through the repression of the PI3K/AKT signaling pathway by down-regulating IGF1R. Therefore, miR-139-5p could pave a new way for the treatment of malignant melanoma.