title: Developmental phase-specific alkaline phosphatase isoenzymes of human placenta and their occurrence in human cancer.
abstract: Alkaline phosphatase electrophoretic patterns characteristic of three phases in early human trophoblast development are described in this preliminary communication. Phase 1 (6 to 10 weeks) consists entirely of two heat-sensitive, L-homoarginine-inhibited bands, the slower one of which possesses antigenic determinants of live-bone-type alkaline phosphatase, whereas the fast band lacks any of the known alkaline phosphatase antigenic determinants. Phase 2 pattern (11 to 13 weeks) is that of a mixture of Phase 1 and Phase 3 isozyme components, the latter exhibiting two isozyme bands with the characteristics of term placental alkaline phosphatases correspond in order to non-Regan isoenzyme, a mixture of Regan and non-Regan isoenzymes and Regan isoenzyme in a variety of human cancer tissues. The biochemical profile characteristic of trophoblast developmental Phase 1 alkaline phosphatase is expressed as 78.5% heat-sensitive inhibition (5 min at 65 degrees), 66.3% L-homoarginine inhibition, and 17.3% L-phenylalanine inhibition where n = 12. It is hypothesized that the alkaline phosphatase of human tumor tissues reflects the expression of placental genes corresponding to one or more phases of trophoblastic development.
mesh_terms: D000469:Alkaline Phosphatase / Q000276:immunology; D004588:Electrophoresis, Cellulose Acetate; D005260:Female; D006801:Humans; D007122:Immunoelectrophoresis; D007527:Isoenzymes / Q000276:immunology; D009369:Neoplasms / Q000201:enzymology*; D010920:Placenta / Q000201:enzymology*; D011247:Pregnancy; D011261:Pregnancy Trimester, First
chemical_list: D007527:Isoenzymes; D000469:Alkaline Phosphatase