It was found that overproduction of prostaglandin-E2 (PGE2) by metastatic murine renal carcinoma (Renca) cells blocked the priming of tumour-special CTLs in vivo by abrogating IFNγ-dependent costimulatory signalling between ICAM-1 and the lymphocyte receptor LFA-1 (104). Here, IFNG is linked to neoplasm.