To investigate the differences in miRNA expression levels between giant congenital melanocytic nevi, medium-sized congenital melanocytic nevi and normal skin.

The experiment was divided into three groups: giant congenital melanocytic nevi group, medium-sized congenital melanocytic nevi group and normal skin group, with ten samples in each group. Firstly, 3 samples of each group were detected by Agilent miRN Amicroarray to screen the different miRNAs between different groups. 5 differential miRNAs related to MAPK, Wnt, NF-kB signaling pathways were selected for further verification: miR-146a-5p, miR-140-5p, miR-106b-5p, miR-17-5p, and miR-483-5p. miRNA expression levels were measured using real-time quantitative PCR (Taqman) in ten clinical samples from each group. .Experimental data were analyzed using SPSS 22.0.

A total of 23 differential miRNAs between congenital melanocytic nevi and normal skin were found by miRNA microarray detection. The results of real-time PCR showed that miR-146a-5p expression was significantly different between the three groups: giant congenital melanocytic nevi VS medium-sized congenital melanocytic nevi (P=0.003); giant congenital melanocytic nevi VS normal skin (P=0.000); medium-sized congenital melanocytic nevi VS normal skin (P=0.013). There was no statistically significant difference in the expression of the other four miRNAs between the 3 groups.

The expression of miR-146a-5p is increased in congenital melanocytic nevi, especially in giant congenital melanocytic nevi, which may be related to the proliferation and senescence of melanocytes in different tissues.

Nevus pigmented; Melanocyte; microRNAs