Abstract
The cellular localization and isoenzyme pattern of alkaline phosphatase in 5 cell lines derived from human bladder carcinomas (T24, RT4, RT112, J82, EJ) shown not to be HeLa cells was established. RT112 cells had a high level of alkaline phosphatase. RT4 had a moderate amount of alkaline phosphatase but in the other 3 lines, levels were extremely low. Prednisolone caused a small (2 to 3-fold) increase in total alkaline phosphatase in T24 and RT112 lines only. Electrophoretic separation of isoenzymes showed that RT112 and RT4 cells (derived from more highly differentiated tumor types) had 3 heat stable bands equivalent to placental alkaline phosphatase and 3 slower bands of a modified placental type. Prednisolone increased only the former. In T24 cells the enzyme resembled the liver-type alkaline phosphatase in electrophoretic mobility and sensitivity to heat denaturation. Cytochemical studies confirmed the presence of cell surface-associated extramembraneous placental type enzyme in RT112 cells. All 5 cell lines had small deposits of intramembraneous alkaline phosphatase in the plasma membrane and deposits associated with the mitochondrial membranes and the endoplasmic reticulum that were not completely inhibited by phenylalanine or Levamisole.
| Original language | English |
|---|---|
| Pages (from-to) | 266-274 |
| Number of pages | 9 |
| Journal | Journal of Histochemistry and Cytochemistry |
| Volume | 25 |
| Issue number | 4 |
| DOIs | |
| State | Published - 1977 |
| Externally published | Yes |