CA9 and cancer: The expression of CA-IX is up-regulated in hypoxia by the transcription factor hypoxia inducible factor-1 (HIF1α) and is associated with the Warburg effect in cancer pathology (Ivanov et al., 2001; Supuran, 2008; Pastorek and Pastorekova, 2015; Shabana and Ilies, 2019).