High expression of uridine diphosphate-galactose: Lc3Cer beta 1-3 galactosyltransferase in human uterine endometrial cancer-derived cells as measured by enzyme-linked immunosorbent assay and thin-layer chromatography-immunostaining.

We have developed a new procedure for the selective determination of beta 1-3 and beta 1-4 galactosyltransferases with Lc3Cer as the substrate and the microsomes of fetal and adult porcine livers as the enzyme sources. This method was based on the detection of such products as Lc4Cer for beta 1-3 galactosyltransferase (beta 1-3GT) and nLc4Cer for beta 1-4 galactosyltransferase (beta 1-4GT), with monoclonal anti-Lc4Cer and anti-nLc4Cer antibodies, respectively. This method thus enabled us to differentiate the activity of beta 1-3GT from that of beta 1-4GT with a high degree of sensitivity. The method was then used to determine the activities of both enzymes in human gynecological carcinoma-derived cells. Four of the five cell lines derived from uterine endometrial cancer expressed significantly high levels of specific activity of beta 1-3GT among the cell lines examined, while their beta 1-4GT activities were less than 20% of that for beta 1-3GT in the endometrial carcinoma-derived cells. On the other hand, a higher specific activity of beta 1-4GT than that of beta 1-3GT was detected in the cell lines derived from uterine cervical and ovarian cancers. These findings were thus found to correlate closely with the rate of expression of Lc4Cer- and nLc4Cer-based carbohydrate chains in the cell lines based on the results of immunohistochemical staining.