Fig. 7: CD31 signaling promotes β-catenin nuclear translocation and upregulates cMyc expression.

WT and cd31^−/− EC monolayers were stimulated by MHC antibody-ligation or treated with an Isotype-matched control and secondary antibodies (2 h). Some cd31^−/− ECs were also treated with an Akt activator (500 nM, 3 h) prior to antibody stimulation. Vehicle was added in the untreated cultures (IsC and MHC ligation). a β-catenin and cMyc expression were determined by immunofluorescent antibody staining and wide-field microscopy. The nucleus was stained with DAPI. The mean fluorescence intensity of cMyc and β-catenin measured in 500 cells in three independent experiments is shown in (b, c), respectively. Scale bar = 40 μm. Data are mean ± SD. one-way Anova with Tuckey post-hoc test. b WT IsC vs WT MHC; c WT IsC vs WT MHC ***p = 0.0008, cd31^−/− IsC + C991 vs cd31^−/− MHC + C991 ***p = 0.0002. d, e: cMyc (d) and aldolase (e) gene transcription by WT (upper panels) and cd31^−/− (lower panels) EC at the indicated time points. n = 3 biologically independent samples, N = 2 independent experiments. Error bars represent SD. One-way Anova with Tuckey post-hoc test or T-test (d, e). d WT IsC 30′ vs WT MHC 30′ **p = 0.003, WT IsC 120′ vs WT MHC 120′ ****p < 0.0001; e WT IsC 30′ vs WT MHC 30′ ***p = 0.0008, WT IsC 120′ vs WT MHC 120′ ****p < 0.0001, WT IsC 240′ vs WT MHC 240′ ****p < 0.0001.