ABCC8 is correlated with immune cell infiltration and overall survival in lower grade glioma

Abstract

ATP binding cassette subfamily C member 8 (ABCC8) encodes a protein regulating the ATP-sensitive potassium channel. Whether the level of ABCC8 mRNA in lower grade glioma (LGG) correlates with immune cell infiltration and patient outcomes has not been evaluated until now. Comparisons of ABCC8 expression between different tumors and normal tissues were evaluated by exploring publicly available datasets. The association between ABCC8 and tumor immune cell infiltration, diverse gene mutation characteristics, tumor mutation burden (TMB), and survival in LGG was also investigated in several independent datasets. Pathway enrichment analysis was conducted to search for ABCC8-associated signaling pathways. Through an online database, we found that ABCC8 expression in LGG was lower than in normal tissues. Then, the association of ABCC8 expression and immune cell infiltration in LGG was discussed. As we expected, the ABCC8 mRNA levels were negatively associated with non-T immune cell infiltration levels in all datasets. Consistently, TCGA_LGG RNA-seq data revealed that ABCC8 downregulated several non-T immune cell-associated signaling pathways in gene set enrichment analysis. Different ABCC8 expression groups showed diverse gene mutation characteristics and TMB. The high expression of ABCC8 was linked to improved survival of LGG patients. A pathway enrichment analysis of ABCC8-associated genes indicated that the GABAergic synapse signaling pathway might be involved in regulating immunity in LGG. Our findings show that ABCC8 reflects LGG tumor immunity and is an ideal prognostic biomarker for LGG.