HES1 shRNA efficiently knocked down HES1 expression at the transcript levels, as shown by qPCR, in the HTMCs under normal and oxidative stress conditions (A). Western blots (B) and their quantification (C) showed the down-regulation of HES1 protein expression by HES1 shRNA in the HTMCs under both norm and oxidative stress. Western blots (D) revealed that the up-regulation of ECM proteins under oxidative stress was subdued (for Fibronectin), reversed (for Laminin), or abolished (for Collagen I and α-SMA) by HES1 shRNA (E). Immunofluorescence confirmed the trends of ECM protein expression changes under both normal and oxidative conditions in the HES1 shRNA-transduced HTMCs (F-U). The data were presented as mean ± SEM (n = 3 per group for each experiment, each experiment was repeated 3 times, ** p < 0.01, *** p < 0.001).