Systematic pan-cancer analysis identifies SLC31A1 as a biomarker in multiple tumor types

Solute Carrier Family 31 Member 1 (SLC31A1) has recently been identified as a cuproptosis-regulatory gene. Recent studies have indicated that SLC31A1 may play a role in colorectal and lung cancer tumorigenesis. However, the role of SLC31A1 and its cuproptosis-regulatory functions in multiple tumor types remains to be further elucidated. Online websites and datasets such as HPA, TIMER2, GEPIA, OncoVar, and cProSite were used to extract data on SLC31A1 in multiple cancers. DAVID and BioGRID were used to conduct functional analysis and construct the protein-protein interaction (PPI) network, respectively. The protein expression data of SLC31A1 was obtained from the cProSite database. The Cancer Genome Atlas (TCGA) datasets showed increased SLC31A1 expression in tumor tissues compared with non-tumor tissues in most tumor types. In patients with tumor types including adrenocortical carcinoma, low-grade glioma, or mesothelioma, higher SLC31A1 expression was associated with shorter overall survival and disease-free survival. S105Y was the most prevalent point mutation in SLC31A1 in TCGA pan-cancer datasets. Moreover, SLC31A1 expression was positively correlated with the infiltration of immune cells such as macrophages and neutrophils in tumor tissues in several tumor types. Functional enrichment analysis showed that SLC31A1 co-expressed genes were involved in protein binding, integral components of the membrane, metabolic pathways, protein processing, and endoplasmic reticulum. Copper Chaperone For Superoxide Dismutase, Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha and Solute Carrier Family 31 Member 2 were copper homeostasis-regulated genes shown in the PPI network, and their expression was positively correlated with SLC31A1. Analysis showed there was a correlation between SLC31A1 protein and mRNA in various tumors. These findings demonstrated that SLC31A1 is associated with multiple tumor types and disease prognosis. SLC31A1 may be a potential key biomarker and therapeutic target in cancers.