Analysis of CFTR gene expression as an immunological and prognostic biomarker in pan-cancers.

Cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-activated chloride channel that regulates fluid homeostasis via ATP binding and uses energy to transport relevant substrates across cytomembranes. It has been reported that CFTR plays a crucial role in the incidence and development of various types of cancers by regulating proliferation, metastasis, invasion and apoptosis. However, aberrant CFTR gene expression across different cancers makes it difficult to propose CFTR as a possible pan-cancer biomarker. Here, multiple databases (ONCOMINE, PrognoScan, Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA)), were accessed to investigate the relationship between CFTR gene expression with the immunological and prognostic roles in pan-cancers. The results showed higher CFTR gene expression in tumor tissues compared to normal tissues for most cancers except for CHOL, ESCA, KICH, LAML, SKCM and STAD. Higher expression of the CFTR gene directly correlated with better prognosis for BRCA, GBM, COAD, KIRP, LAML, LUAD, PRAD, SARC and STAD, and CFTR gene expression was higher in stage Ⅰ_Ⅱ compared to stage Ⅲ_ Ⅳ. Furthermore, CFTR gene expression levels were significantly associated with immune infiltrates and immunocytes, in particular, immune checkpoints, in COAD, LIHC, LUAD and LUSC. In conclusion, CFTR can be used as a prognostic marker for nine types of cancers examined in this study where CFTR expression levels play a vital role in forecasting the clinical efficacy of immune checkpoint suppression therapy.