Compared to NT T cells, 5T4 CAR‐T cells produced significantly higher levels of IL‐2 (1500‐2000 pg/mL), IFN‐γ (about 2000 pg/mL) and GM‐CSF (1600‐2300 pg/mL), a little bit higher levels of TNF‐α (about 100 pg/mL) and IL‐6 (40‐300 pg/mL) when cocultured with 5T4+ ovarian cancer cells at the E/T ratio of 10:1 (Figure 4B). Here, IL2 is linked to ovarian cancer.