“…Amplification of the c-erbB-2 gene and overexpression of its product induce cell transformation (Di Fiore et al, 1987) and have been associated with poor prognosis in different tumours of epithelial origin (Rilke et al, 1991;Berchunck et al, 1990;Kern et al, 1990;Gullick, 1990;Slamon et al, 1989). Monoclonal antibodies (MAbs) directed to pl85HER2 (Hurwitz et al, 1995;Stancovski et al, 1991;Tagliabue et al, 1991;Hudziak et al, 1989;McKenzie et al, 1989), as well as different candidate ligands of the p185HER2 receptor (Samanta et al, 1994;Huang et al, 1992;Wen et al, 1992;Holmes et al, 1992;Peles et al, 1992;Dobashi et al, 1991, Tarakhovsky et al, 1991Lupu et al, 1990;Yarden et al, 1989) and oestrogen (Matsuda et al, 1993), have been shown either to stimulate or to inhibit cell growth. c-erbB-2 can also be activated by interaction with other activated members of the EGF receptor family.…”