Low Expression of Indicates Poor Prognosis in Melanoma.

BACKGROUND

Melanoma is a highly malignant skin tumor with a poor prognosis. Identification of novel biomarkers might potentially reveal the underlying mechanisms of melanoma progression.

METHODS

We demonstrated the relationship between pan-cancer expression and melanoma samples in The Cancer Genome Atlas (TCGA) database. Next, the Kaplan-Meier plot and Cox regression analysis determined the prognostic value of in melanoma. Biological pathway enrichment was screened by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA), enabling the correlation analysis between the immune infiltration level and expression in melanoma. Our final claim was validated using qPCR, immunohistochemistry, Western blot, cell colony formation assays, ethynyldeoxyuridine (Edu) analysis, and cell Invasion assays.

RESULTS

Our study revealed that the high expression correlates with poor overall survival of melanoma patients. Moreover, a low expression of was found in the A375 cell line. In addition, has significant prognostic value in melanoma diagnosis, with an AUC of 0.896. Prognostic analysis showed the low expression of to be independently associated with melanoma patients. Moreover, the expression of was significantly correlated with B cells, eosinophils, macrophages, neutrophils, NK cells, T helper cells, Tregs, Th1 cells, Th17 cells, and Th2 cells. PCR and immunohistochemistry indicated to be significantly downregulated in melanoma. The cell colony formation assay showed knockout increased the proliferation of A375 cells.

CONCLUSION

Our study established low levels of to be poor prognostic markers, enabling immunosuppressive cell infiltration in melanoma.