Differential signaling pathway activation in resistant and sensitive breast cancer cells upon treatment with 17AAG. Transfections were carried out in the sensitive (MCF-7 and Hs578T) and resistant (MDA MB 231 and T47D), cells with the reporter constructs for the typical cancer biology pathways: NOTCH, WNT, TGFβ, P53, cell cycle, MYC/MAX, NF-κB, MAPK/ERK, MAPK/JNK and HIF, followed by 17AAG or DMSO treatment. Dual-luciferase assay was performed, and promoter activity values are expressed as arbitrary units using a Renilla reporter for internal normalization. The experiment performed itself in triplicates was repeated at least twice of each cell line studied. The error bars represent standard deviation. Pathways significantly (p-value < 0.05) repressed or activated are marked with a star.