Ouabain suppressed the CoCl2-induced expression of HIF-1α in human skeletal muscle cells in a time- and concentration-dependent manner (Figure 7), consistent with suppressive effect of ouabain and other CTS on the HIF-1α abundance in cancer (Zhang et al., 2008) and smooth muscle cells (Koltsova et al., 2014). This evidence concerns the gene HIF1A and cancer.