miR-367 enhances the proliferation and invasion of cutaneous malignant melanoma by regulating phosphatase and tensin homolog expression

Melanoma presents a serious threat to human health but the underlying mechanisms have not been fully identified. Increasing evidence indicates that microRNAs exert a significant influence on the tumorigenesis and metastasis of different types of cancer. The present study aimed to identify the role of microRNA (miR)-367 in the initiation and progression of melanoma and investigate its potential target. A total of 50 melanoma samples and 25 benign nevi tissues were used in the present study. Reverse transcription-quantitative polymerase chain reaction and western blot analysis were performed to determine the expression of mRNA and protein, respectively. Cell proliferation and invasion were assessed by CCK-8, wound healing and Transwell assays. A proposed target mRNA of miR-367 was determined using a luciferase reporter assay and an in vivo xenograft model was used to evaluate the function of miR-367 in the progression of melanoma. It was revealed that miR-367 was overexpressed in melanoma tissues and cell lines. The miR-367 level in tumor tissues was positively correlated with tumor thickness, tumor stage, lymph node involvement, distant metastasis and the patient survival rate. A high miR-367 level was observed to enhance the growth, migration and invasion of melanoma cells. Conversely, low miR-367 levels suppressed the proliferation and invasion of melanoma cells. Furthermore, miR-367 was revealed to bind directly to phosphatase and tensin homolog (PTEN) mRNA and regulate the expression of the PTEN protein. miR-367 markedly increased the growth and invasion of melanoma cells, whereas the cotransfection of PTEN vectors limited the promoting function of miR-367 in the proliferation and invasion of A375 cells. The upregulation of miR-367 promoted tumor growth in vivo. In conclusion, the results revealed that miR-367 serves a positive role in the development of melanoma and may be an important target for the treatment of cutaneous melanoma.