CD8A and colon carcinoma: Qin and Blankenstein (2000) and Qin et al (2003) showed that rejection of different tumours by CD8+ T cells was always preceded by inhibition of tumour-induced angiogenesis. Moreover, in some murine models, the antiangiogenic activity mediated by IL-12 and IL-18 was shown to be IFN-γ mediated (Voest et al, 1995; Cao et al, 1999), and inhibition of angiogenesis by IFN-γ was found to occur in colon carcinoma through transcriptional silencing of perlecan gene expression (Sharma and Iozzo, 1998).