In particular, we evaluated TCR ζ and ɛ chains, p56lck, Bcl-2 and Bax expression, FasL and Fas expression on the surface of TIL from surgically obtained tumour samples, and reassessed the same parameters, with the addition of perforin, after TIL were coincubated with IL-2. The gene discussed is BCL2; the disease is neoplasm.