KCNH2 and colorectal carcinoma: Accordingly, σ1R molecular silencing reduces current density in colorectal cancer (CRC) and leukemia cell lines, demonstrating that, in the absence of any ligand, σ1R stimulates hERG function (Crottès et al., 2011, 2013, 2016), a result which is in contrast with those obtained with Kv1.5 channels in Xenopus oocytes where σ1R behaves as a negative modulator (Aydar et al., 2002; Crottès et al., 2013).