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 with different chemical structure on IP3 (inositol-1,4,5-trisphosphate) formation and intracellular Ca++ concentration was studied in human mammary epithelial cells before and after transfection with v-erb B oncogene DNA. Transformed cells showed an increased IP3 formation compared with normal cells. In the presence of ALP (alkyllysophospholipid) analogs IP3 formation in inhibited more strongly in transformed cells than in normal cells, dependent on the structure of ALP analogs. Furthermore, these compounds increased [Ca++](i) (intracellular Ca++ concentration) in transformed cells much more strongly than in normal cells. From these results, obtained in pursuit of an oncogene-related cancer treatment, it follows that ALP analogs may inhibit processes in signal transduction in cells more strongly after transfection with a defined oncogene than before.