Alkaline phosphatase activity in cultured meningioma cells.
The specific activity of alkaline phosphatase in cultured human meningioma cells varies over a relatively wide range. There is no correlation between the levels of activity and the histological type of  meningioma from which the cultures were derived. The enzyme is heat-labile and is strongly inhibited by L-homoarginine, levamisole, and 1-bromotetramisole, but unaffected by L-phenylalanine and L-phenylalanyl-glycylglycine. These findings indicate that meningioma cells synthesize the liver/bone/kidney form of alkaline phosphatase. In contrast to cultures derived from pituitary adenomas, glioblastomas, and astrocytomas in which prednisolone and/or sodium butyrate elicit a manifold increase of alkaline phosphatase activity, with meningioma cells the hormone causes only a slight augmentation in specific activity, and the fatty acid is ineffective. As with other cells producing the liver/bone/kidney enzyme form, no increase in activity occurs in meningioma cells growing in hyperosmolar medium.
D000469:Alkaline Phosphatase / Q000032:analysis*; D002478:Cells, Cultured; D006801:Humans; D007527:Isoenzymes / Q000032:analysis; D008577:Meningeal Neoplasms / Q000201:enzymology*; D008579:Meningioma / Q000201:enzymology*; D009994:Osmolar Concentration
D007527:Isoenzymes; D000469:Alkaline Phosphatase