Fig. 3

Basal and treatment dependent variation in XBP1 levels were quantified using the XBP1 biochip. XBP1s and XBP1u levels in MCF7, SKBR3 and MDA-MB-231 cell lines were assessed by immunoblot (a) and XBP1 biochip (b). MCF10A (± 0.5 mM Tg) were included as negative and positive controls. * p < 0.05. MCF7 and MDA-MB-231 cells were treated with vehicle (DMSO) or IRE1α RNase inhibitors 4μ8C (32 μM) or MKC-8866 (20 μM) for 48 h and assessed by immunoblot (c) and XBP1 biochip (d). XBP1 biochip assessment of MDA-MB-231 cells following 48 h treatment with XBP1 splicing inducing chemotherapeutic Paclitaxel (10 nM) and IRE1α RNase inhibition (e)