Lapatinib works in conjunction with Th1 cytokines to suppress metabolic activity of breast cancer cell lines.

Cultured SK-BR-3, BT-474 and MDA-MB-468 cells were treated either with Th1 cytokines (TNF-α plus IFN-γ; 20 and 12.5ng/ml respectively), Lapatinib (200nM), Lapatinib plus Th1 cytokines or left untreated (control). After 72 hours incubation, resazurin sodium salt was added to each well and further incubated until color change was noted, and optical densities of supernatants read spectrophotometrically at 630nM. Shown are composite data from at least three trials per cell line expressed as mean optical density +/- SEM. Statistical significance was determined by one-way ANOVA followed by the Holm-Sidak multiple comparison test.