SPINT2 and breast carcinoma: Furthermore, the high levels of 25-kDa HAI-2 and the relatively constant ratio of the 25-kDa form relative to the 30- and 40-kDa HAI-2 forms in a variety of cell lines supports the idea that 25-kDa HAI-2 might in fact be an independent entity rather than a precursor and/or intermediate of N-glycan branching in HAI-2-expressing cells not limited to breast cancer cells.