Fig. 6
TME conditions decrease proliferation and increase apoptosis signaling, while hypoxia alone has no effect. HUVECs or Ea.hy926 were exposed to normoxic control (Ctrl), TME (1% O2, 1% FBS, 2.5 mM glucose, 7.5 mM lactate and pH 6.5) or hypoxic (Hyp; 1% O2) conditions as indicated, for 24 or 48 h followed by lysis and western blotting. NHE1 was inhibited by cariporide (10 μM) or knocked down by siRNA-treatment where indicated. GAPDH is shown as loading control. a, b, c Representative western blots of p-Ser807/811-pRb and quantifications of the p-pRb protein levels relative to the untreated control condition for 24/48 h for HUVEC (a, b) and 24 h for Ea.hy926 (c). Two-way ANOVA revealed a significant difference in p-pRb levels between conditions (Ctrl, TME, Hyp) with p < 0.05 for HUVEC and p < 0.01 for Ea.hy926, respectively. d Representative western blots showing PARP protein levels and quantification of cleaved PARP relative to the untreated control for 24 h in HUVEC. Data are presented as means with SEM error bars, with n = 3–5