Figure 8.

Western blot analysis of total and phosphorylated ErbB receptor levels treated with γ-tocotrienol (γT³), erlotinib (E) or gefitinib (G) either alone or in combination. +SA mammary tumor cells were plated at a density of 1 × 10⁶ cells/100-mm culture dish and treated with control or treatment serum-free defined media containing EGF as mitogen. After a 4-day incubation period, whole cell lysates were subjected to PAGE followed by Western blot analysis for total and phosphorylated (active) ErbB receptor levels. Each Western blot is a representative example of data obtained for experiments that were repeated at least three times.