Identification of hub anoikis-associated genes and risk signature in cutaneous melanoma.

Abstract

As one of the most lethal and aggressive cutaneous malignancies, cutaneous melanoma (CM) greatly threatens human health and has long challenged clinicians because of its poor therapeutic response. Anoikis is a newly discovered form of apoptosis that was originally identified in the extracellular matrix (ECM). Recent studies have reported that anoikis is central to cancer metastasis. The aim of this study is to explore the role of anoikis-associated genes in CM. We identified hub anoikis-associated genes in CM and constructed a risk signature for patients with CM. Gene expression from The Cancer Genome Atlas (TCGA) database was used to screen hub anoikis-associated genes connected with CM, and the Gene Expression Omnibus (GEO) dataset was applied to externally validate the identified genes. Weighted gene co-expression network analysis (WGCNA), differential expression, univariate Cox regression, and least absolute shrinkage and selection operator (LASSO) analyses were used to identify hub genes. Immune cell infiltration in CM was also evaluated to explore the association between hub genes and immune heterogeneity. Finally, an anoikis-associated prognostic model was constructed. Following complex analysis, FASLG, SOD2, BST2, PIK3R2, IKZF3, CDK2, and RAC3 were identified as hub anoikis-associated genes. Indeed, Kaplan-Meier and receiver operating characteristic analyses suggested that the expression patterns of hub genes can be used as prognostic factors for CM survival. The expression and survival trends of hub genes were verified in the validation cohort. Immune cell infiltration analysis showed that the number of immune cells varied among patients with CM and identified seven genes. Furthermore, functional analyses indicated that the constructed risk signature was significantly associated with patient survival, age, and tumor growth and could also serve as an independent prognostic factor for patients with CM. We suggest that the hub genes FASLG, SOD2, BST2, PIK3R2, IKZF3, CDK2, and RAC3 are involved in the anoikis-associated signature. The pattern of hub anoikis-associated genes may have a prognostic potential for CM progression and overall patient survival.