NT5E and cancer: Though hypoxia is a formidable inducer of CD73 in cancer, CD73 expression on various cell types can be induced by a number of factors, including interferon-β-1a (Bellingan et al., 2014), the zinc finger transcription factor growth factor independence 1 (GFI-1) (Chalmin et al., 2012) and cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) (Bao et al., 2016), as well as epigenetically (Wang et al., 2012), due to estrogen receptor expression (Spychala et al., 2004) or via Wnt signaling (Spychala and Kitajewski, 2004; Zhan et al., 2017).