Pan-cancer analyses reveal the immunotherapeutic value of klotho.

Klotho (KL) was initially thought to be a typical "ageing suppressor" gene, but recent studies have suggested that KL is involved in the progression of several types of human cancer. This study aims to analyse whether the expression level of KL could impact patient prognosis, clinical parameters, and tumour immunity in different tumour patients. KL activity was utilized to determine differences between the KL transcript and KL protein. Expression levels were detected by single-sample gene enrichment analysis (GSEA). To explore the inherent mechanisms of KL in tumour immunotherapy, we investigated the possible impact of KL on the tumour microenvironment, immune processes and immune components. GO and KEGG analysis showed that KL was significantly involved in immune response, Inflammation, and calcium signaling pathway. We also found that KL was significantly correlated with multiple immunotherapeutic biomarkers (TMB, MSI, CD274, PDCD1, CTLA4 and TIGIT) in a variety of tumours. Furthermore, increased KL expression was closely associated with the non-response of anti-PD-1 immunotherapy, indicating that KL might affect the response sensitivity of tumour patients to anti-PD-1 immunotherapy. This study will provide a basis for further research on how KL regulates tumour immune cells and may lead to the development of more effective target tumour immunotherapy.