The statistically significant negative correlation (p < 0.05 and Rho < 0) was observed between the expression of SMYD2 and immune infiltration of CD8+ T cell in BRCA basal (Rho =  − 0.160, p = 0.034), CESC (Rho =  − 0.137, p = 0.023), COAD (Rho =  − 0.171, p = 0.004), ESCA (Rho =  − 0.287, p = 9.50E-05), HNSC (Rho =  − 0.220, p = 7.69E-07), and PAAD (Rho =  − 0.195, p = 0.010) cancers of TCGA based on most or at least one algorithm (Supplementary Table 2). This evidence concerns the gene CD8A and cancer.