Under in vitro or immunodeficient in vivo conditions, ANO1 knockdown evidently suppressed GC's proliferation/migration/invasion and peritoneal/liver/lung metastasis, suggesting ANO1 itself plays a cancer promotive role independent of the immune system, which might be due to ANO1's function in activating PI3K‐Akt signaling and inhibiting ferroptosis in cancer cells. Here, ANO1 is linked to cancer.