CD4 and nonpapillary renal cell carcinoma: ssGSEA analysis iedentified multiple types of immune cell infiltration in TCGA ccRCC samples, among which central memory CD4+T, activated CD4+T and effector memory CD8+T cells found to be positively correlated with DDX39 expression, while immature dendritic, CD56+(bright) nature killer and type 17 T helper cells were found to be negatively correlated with DDX39 expression (Figure 8B, C).