More and more evidences show that the downregulation of FAT4 may be related to the pathogenesis of several malignancies, and FAT4 has been identified as a tumor suppressor in various cancers, including gastric, breast and colorectal cancer (2–4), which contributes to the inhibition of cell proliferation and invasiveness, and thus suppresses metastasis. The gene discussed is FAT4; the disease is cancer.