TUMOR-CELL GROWTH-INHIBITION BY SEVERAL ANNONACEOUS ACETOGENINS IN ANIN-VITRO DISK DIFFUSION ASSAY

The cell inhibition activities of several Annonaceous acetogenins, cov ering the three major structural classes of bisadjacent, bis-non-adjac ent, and single tetrahydrofuran (THF) ring compounds and their respect ive ketolactone rearrangement products, were tested in an in vitro dis k diffusion assay against three murine (P388, PO3, and M17/Adr) and tw o human (H8 and H125) cancerous cell lines as well as a non-cancerous immortalized rat GI epithelial cell line (118). The results demonstrat e a dose-dependent inhibition of cancerous cell growth, while non-canc erous cell growth is not inhibited by the same dosages. All of the ace togenins, irrespective of their various structural types, inhibit the growth of adriamycin resistant tumor cells and non-resistant tumor cel ls at the same levels of potency. These results show that the Annonace ous acetogenins are an extremely potent class of compounds, and their inhibition of cell growth can be selective for cancerous cells and als o effective for drug resistant cancer cells, while exhibiting only min imal toxicity to 'normal' non-cancerous cells.