Figure 1: Notch3 is aberrantly expressed in tumour endothelial cells.

(a) Notch3 immunohistochemistry on peritumoral and tumour part of three sections from non-small cell lung cancers patients. (b) Quantitative RT-PCR was performed to measure Notch3 mRNA expression in endothelial cell enriched fraction (EC, CD31-expressing purified cell population) or non endothelial cell (NEC) purified from lung dissected from wild-type mice, the healthy part of tumour-bearing lung dissected from Kras mice or from the nodules dissected from the lung of Kras mice (n=6 WT lungs, n=5 Kras lungs, mean±s.e.m., ordinary one-way ANOVA, multiple comparisons). (c,d) β-galactosidase staining was performed on lungs or LLC1 tumour whole mount from Kras^G12D/+ (c) or WT mice (d) mice before inclusion in paraffin and immunohistochemistry staining for ERG, CD31, SMA, NG2 as indicated. (e) Quantitative RT–PCR was performed to measure Notch3 mRNA expression in endothelial cell FACS-sorted from lung or tumour dissected from Cdh5:Cre^ERT2xTomato (Ve-Cad Tomato) mice (n=3 tumours, mean±s.e.m., unpaired t-test). (f) HUVEC cells were co-cultured for 48 h with LLC1 cells stably expressing GFP before being FACS sorted. DAPI (alive cells) GFP negative (HUVEC) cells were used to prepare mRNA and Notch3 expression was measured by quantitative RT–PCR (n=3 independent experiments, paired ratio t-test).