C1GALT1 and neoplasm: Reports of tumor-associated O-linked glycosylation includes Core 1 β1-3 galactosyltransferase (C1GALT1), C1GALT1-specific chaperone (COSMC), Core 2 β1,6-N-acetylglucosaminyltransferase-1 (C2GNT1), Core 2 β1,6-N-acetylglucosaminyltransferase-2 (C2GNT2), and Core 3 β1,3-N-acetylglucosaminyltransferase 6 (B3GNT6) (Curigliano et al., 2020; Martinez-Saez, Peregrina & Corzana, 2017; Miyamoto et al., 2013; Okamoto et al., 2013; Schachter & Brockhausen, 1989; Sindrewicz, Lian & Yu, 2016).