Expression and kinetic changes of alkaline phosphatase and its isoenzymes in experimental rat hepatoma.

AIM:To explore the expression and changes of hepatoma specific alkaline phospatase (ALP) in rats during canceration.METHODS:The ALPs and isoenzymes of rat livers and sera were investigated in SD hepatomas induced with 0.05% 2-fluoenylacetamide (2-FAA).RESULTS: By pathological examination and biochemical analysis. ALPs were overexpressed in rat livers during canceration and then were secreted into blood. Serum total ALP activities, liver ALP specific activities (U/g) including soluble and membrane-combined ALP activities of each group were all significantly higher (P < 0.01)than those of control group. The average ratios of soluble ALP to membrane-combined ALP were increased significantly after 6 weeks. ALP isoenzymes of rat sera and livers showed 5 bands on PAGE:ALP-I and ALP-II were specific for normal liver and rat hepatoma tissues, the ALP-II appeared in rat liver after 6 weeks and in sera after 8 weeks.CONCLUSION:ALP with carcino-embryonic protein was overexpressed in hepatoma tissues; the abnormal ALP-II of ALP isoenzymes in sera and liver of rats can be used as a tumor marker for early diagnosis of rat hepatoma.