Fig. 3: Epithelial:fibroblast crosstalk induces IFNβ1 expression in CAFs and IFN signalling in epithelial cells.

a MDA-MB-231-GFP/luc cells were cultured alone, breast CAFs were cultured alone, or co-cultures of MDA-MB-231-GFP/luc cells and CAFs were established (80% epithelial cells with 20% fibroblasts: “20%”). CAFs used were either immortalised, left, or primary, right. Cultures were treated with or without 10 nM epirubicin for 24 h. All cultures were processed for cell sorting, allowing separation of CAFs and MDA-MB-231-GFP/luc cells from the co-cultures on the basis of GFP fluorescence in the CAFs. RNA was extracted, and qPCR used to determine relative expression of IFNβ1. Data represent the mean of duplicate culture wells (±SD) for one biological experiment. ND not detected. b MDA-MB-231 cells were transfected with ISRE or GAS reporter plasmids driving firefly luciferase expression, and a control plasmid (pRL-TK; HSV thymidine kinase promoter driving renilla luciferase). Transfected MDA-MB-231 cells were then cultured on their own or with different proportions of immortalised NFs or CAFs for 24 h with 10 nM epirubicin. Dual luciferase assays were performed, with firefly readings normalised to renilla readings. Data represent means (±SD) for triplicate wells, for one biological experiment.