Indolocarbazole poisons of human topoisomerase I: regioisomeric analogs of ED-110
4区 · 医学
作者: Zembower, David E. ; Zhang, Heping ; Lineswala, Jayana P. ; Kuffel, Mary J. ; Aytes, Shelley A. ; Ames, Matthew M.
All four "symmetrical" regioisomers of ED-110, an indolocarbazole derivative having potent activity against human topoisomerase I (Topo I) were synthesized. The isomer containing hydroxyl groups in the 3- and 9-positions was approximately ten-fold more active against Topo I, and 5- to 35-fold more active against human solid tumor cell lines in vitro, relative to ED-110.
1993-05-01·Japanese Journal of Cancer Research
ED-110, a novel indolocarbazole, prevents the growth of experimental tumors in mice
A new indolocarbazole compound, ED-110, which was obtained by glucosylating a microbial product (BE-13793C) and is a potent topoisomerase I inhibitor, showed characteristic inhibitory effects on the growth of 12 human tumor cell lines tested. The IC50 values of ED-110 against 9 of the 12 lines ranged from 11.5 micrograms/ml to 0.07 microgram/ml, while the remaining 3 lines were quite resistant (IC50, > 100 micrograms/ml). In in vivo experiments, i.p. treatment with ED-110 increased the survival period by more than two-fold in mice implanted i.p. with P388, L1210, L5178Y or EL4 murine leukemic cells. The minimum effective dose increasing the life-span of mice bearing P388 leukemia by 25% was < 2.5 mg/kg/day x 10 and the maximum tolerated dose was > 160 mg/kg/day x 10. ED-110 was also effective against the spontaneous metastasis of mouse Meth A fibrosarcoma cells and the growth of xenografted MKN-45 human stomach cancer cells as well as s.c. implanted mouse colon 26 and IMC carcinoma cells. These results indicated that ED-110 may have potential as a new antineoplastic agent with a large chemotherapeutic index and a wide range of effective doses.
1993-02-01·Cancer Research1区 · 医学
Induction of topoisomerase I-mediated DNA cleavage by a new indolocarbazole, ED-110
ED-110 is a new semisynthetic antitumor agent derived from a novel indolocarbazole antibiotic, BE-13793C, produced by an actinomycete. ED-110 induced topoisomerase I-mediated DNA cleavage in vitro as strongly as camptothecin, whereas topoisomerase II-mediated DNA cleavage was not induced by this agent. Exposure of P388 cells to ED-110 caused a typical topoisomerase toxicity, i.e.: formation of cleavable complexes; inhibition of nucleotide synthesis rather than protein synthesis; and cell cycle arrest in G2. ED-110 inhibited the growth of P388 cells, with a 50% growth-inhibitory concentration of 44 nM. ED-110 is distinguished from camptothecin by its very different structure and its ability to intercalate into double-stranded DNA. These results suggest that ED-110 has potential as a novel antitumor agent targeting topoisomerase I.