EFFECT OF ALP ANALOGS ON INOSITOL TRISPHOSPHATE FORMATION IN H183 MAMMARY EPITHELIAL-CELLS BEFORE AND AFTER TRANSFECTION WITH V-ERB-B ONCOGENE

The influence of cytostatically active alkyllysophospholipid analogs w ith different chemical structure on IP3 (inositol-1,4,5-trisphosphate) formation and intracellular Ca++ concentration was studied in human m ammary epithelial cells before and after transfection with v-erb B onc ogene DNA. Transformed cells showed an increased IP3 formation compare d with normal cells. In the presence of ALP (alkyllysophospholipid) an alogs IP3 formation in inhibited more strongly in transformed cells th an in normal cells, dependent on the structure of ALP analogs. Further more, these compounds increased [Ca++](i) (intracellular Ca++ concentr ation) in transformed cells much more strongly than in normal cells. F rom these results, obtained in pursuit of an oncogene-related cancer t reatment, it follows that ALP analogs may inhibit processes in signal transduction in cells more strongly after transfection with a defined oncogene than before.