Comprehensive pan-cancer analysis of KRT6A as a prognostic and immune biomarker.

Keratin 6 A (KRT6A) is a member of the keratin family and can participate in the occurrence and development of some tumors. However, there is still a lack of pan-cancer analysis of KRT6A in humans. We studied the pan-cancer role of KRT6A with the help of a variety of external public databases (mainly including TCGA, GTEx, HPA, TIMER2.0, UALCAN, TISIDB, GEPIA2, Kaplan-Meier Plotter, cBioPortal and TISCH2, etc.). We performed immunohistochemistry detection of KRT6A protein expression in lung adenocarcinoma (LUAD) and its adjacent normal tissues. The results showed that KRT6A mRNA and protein were differentially expressed in most tumors, and its expression and function may be regulated by DNA methylation, RNA methylation and protein phosphorylation, and were related to the prognosis and clinical subtypes of patients with different tumors. KRT6A has multiple genetic and epigenetic characteristics in different cancers, and the main type of its genetic variation is mutation. At the same time, KRT6A is closely related to tumor mutation burden (TMB), microsatellite instability (MSI), tumor stemness score (TSC), immune checkpoints, immunomodulatory genes, and tumor immune microenvironment (TIME) in different human tumors. Secondly, the expression level of KRT6A is associated with immunotherapy and drug sensitivity. In addition, bioinformatics analysis and immunohistochemistry experiments verified that KRT6A mRNA and protein were up-regulated in LUAD, and could promote the development process of LUAD by promoting processes such as epidermis development, intermediate filament cytoskeleton and cornified envelope. This is the first pan-cancer analysis of KRT6A, which provides a comprehensive and systematic understanding of its role in various human tumors, and also reveals that KRT6A is expected to become a potential prognostic biomarker and a new target for cancer immunotherapy.