TERT and cancer: Interestingly, in many cancers, activation of TERT was reported to be frequently due to TERT promoter mutations; subsequently noted to overlap with the TERT promoter G4-forming stretch (Akincilar et al., 2016b; Sharma and Chowdhury, 2022; Palumbo et al., 2009; Lim et al., 2010; Huang et al., 2013; Horn et al., 2013; Killela et al., 2013; Li et al., 2016; Akincilar et al., 2016a).