KISS1 is a potential immunological and prognostic biomarker for cancer metastasis in pan-cancer and affects breast cancer in a different way

Metastasis to other organs accounts for the majority of death in cancer patients. Metastatic capacity enables tumor cells resist to chemotherapy. KISS1 had been found to suppress metastasis in cancers like melanoma, but improve the metastatic phenotype of breast cancers, which means its role in tumor metastasis is tissue context-dependent. This character suggests the KISS1 might have promising potential to interpret tumor metastasis in a pan-cancer perspective. Here, we analyzed the potential functions of KISS1 in pan-cancer, especially in breast cancer, by the datasets of TCGA and GTEx. KISS1 exhibited a different expression status between mRNA level and protein level in pan-cancers, with a significant association between KISS1 expression and prognosis of cancer patients. Besides, the correlation between KISS1 expression and immune cell infiltration, immunosuppressive cells, immune checkpoint genes, TMB, MSI, tumor purity and HRD indicates the potential role in regulating immunotherapy. Thereafter, we further clarified the role of KISS1 in promoting metastasis in breast cancer. Furthermore, we found that the post-translational modification may explains the KISS1 protein stability in breast cancers. In summary, our first pan-cancer study offers new insights and relatively comprehensive understandings of the oncogenic roles of KISS1 across various cancers.