Whereas in normal macrophages and neoplastic myeloid and NK cells, IFNγ prevents apoptosis (Lotem and Sachs, 1996; Mizuno et al, 1999; Xaus et al, 1999), it enhances apoptosis of tumour cells in malignancies such as pancreatic carcinoma, colon carcinoma and ovarian carcinoma (Adachi et al, 1999; Burke et al, 1999; Detjen et al, 2001). The gene discussed is IFNG; the disease is colon carcinoma.