To evaluate the in vitro effect of rhIL‐12 on CEA‐CAR‐T cell activation, four experimental conditions were set in which cancer cells are incubated with control‐T cells, control‐T cells and rhIL‐12, CEA‐CAR‐T cells, and CEA‐CAR‐T cells and rhIL‐12, respectively. The gene discussed is CEACAM5; the disease is cancer.