In order to verify our hypothesis and predictive results of bioinformatics, we performed IHC analysis of KCC2 (SLC12A5) and NKCC1 (SLC12A2) to reveal the staining distribution in tumor and adjacent normal tissues of glioma (from AHYMUN cohort), renal cell carcinoma (from FUSCC cohort), and liver and breast cancer (from PHZU cohort). Here, SLC12A5 is linked to renal cell carcinoma.