Fig. 1.
Pharmacological blockade of FAS activity down-regulates expression and activity of p185HER2 oncoprotein. (A) SK-Br3 cells were cultured in the presence of cerulenin for 48 h. Twenty micrograms of protein was subjected to Western blot analyses with the p185HER2 Ab-3. Activation status of HER2 was analyzed by assessing tyrosine phosphorylation of p185HER2 using the anti-phosphotyrosine Ab 4G10. (B) HER2 concentration in cell lysates from cerulenin-treated SK-Br3 cells was quantified by using the Human neu Quantitative ELISA System per the manufacturer's instructions. Data are presented are means ± SD (bars) (n = 3, in duplicate). (C) SK-Ov3 cells was cultured in the presence of C75 for 48 h. Twenty micrograms of protein was subjected to Western blot analyses for HER2 expression as described in A. (D) BT-474, MDA-MB-453, and T47-D breast cancer cells were cultured in the presence of 10 μg/ml cerulenin for 48 h. Twenty micrograms of protein was subjected to Western blot analyses for HER2 expression as described in A.