In tumour cell lines, the sensitivity to several chemotherapeutic agents (Kroning et al, 1995; Dixit et al, 1997; Nouri et al, 2000) and radiotherapy (Kwok and Sutherland, 1989; Bonner et al, 2002) was significantly modified by EGF or EGFR expression levels. The gene discussed is EGFR; the disease is neoplasm.