In this study, by performing correlation and causal network analysis on the cancer transcriptome data, we isolated 40 chemotherapy associated immune feature genes of each cancer (BLCA, BRCA, COAD, SKCM, LUSC, UCEC and OV), and identified six co-owned immune feature genes: CD48, GPR65, C3AR1, CD2, CD3E and ARHGAP9. This evidence concerns the gene C3AR1 and cancer.