miR-22 negatively regulating NOD-like receptor protein 3 gene in the proliferation, invasion, and migration of malignant melanoma cells

Malignant melanoma (MM) is a highly aggressive skin tumour. To investigate whether miR-22 is involved in the proliferation, invasion, and migration of melanoma cells (MCs) by negatively regulating NOD-like receptor protein 3 (NLRP3) gene. Human MCs (WM239a) and human epidermal melanocytes (HEM) were used as study material. The expression levels of miR-22 and NLRP3 were detected by qRT-PCR. The expression of NLRP3 protein was determined by Western blot (WB) analysis. The effects of miR-22 and NLRP3 on the proliferation, invasion, and migration of MCs were evaluated by cell counting kit-8 (CCK-8), Transwell cell invasion assay, and scratch assay. The expression of miR-22 was clearly lower in WM239a than in HEM. Up-regulation of miR-22 expression in WM239a clearly raised the expression of miR-22, Caspase-1, and E-cadherin and the apoptotic rate of WM239a; however, the levels of interleukin-1β (IL-1β) and NLRP3, cell proliferation activity, invasion and migration ability were clearly decreased. The negative regulation of NLRP3 by miR-22 may play a major role in activities of MM. Further studies will help to reveal the molecular details of this regulatory mechanism and provide new therapeutic strategies.