ST6GALNAC1 and breast cancer: Similarly, previous studies showed that most breast cancer cell lines, such as MCF-7, MDA-MB-231 and T47D (Julien et al., 2001, 2006; Sewell et al., 2006), and lung cancer cell line, including A549 (Lakshmanan et al., 2021), do not express hST6GalNAc I mRNA transcript or sTn antigen.