Abstract
Four distinct types of human alkaline phosphatase (AP) have been identified in healthy individuals. These APs are of liver/bone/kidney, adult intestine, placenta and germ cell. An AP was found in sera, ascitic fluid or cancer tissues of patients with hepato-cellular carcinoma which had a different electrophoretic mobility from those of normal enzymes on 5% PAGE. This enzyme initially regarded as a variant of placental AP in view of its enzymatic and immunological properties. Afterwards, on the basis of the identity of this enzyme with one of the two AP isoenzymes produced in FL-amnion cells, this enzyme was designated as the Kasahara isoenzyme (K. I.) after the first patient. Gene analysis of K. I. revealed that the amino acid sequence of K. I. is identical with that of adult intestinal AP, suggesting that the different electrophoretic mobility of K. I. may be due to the aberrant glycosylation of adult intestinal AP. Clinicopathological findings are also reported.
