In vitro and in vivo inhibition of glioblastoma and neuroblastoma with MDL101731, a novel ribonucleoside diphosphate reductase inhibitor.
We examined the effects of MDL101731, a novel ribonucleoside reductase inhibitor, against human glioblastomas and neuroblastoma, both in vitro and in xenograft models, to determine its activity against malignant brain tumors. MDL101731 produced a concentration-dependent inhibition of both glioblastoma cell lines (HS683 and J889H) and neuroblastoma (SK-N-MC) in nanomolar concentrations (IC50, 30-90 nM). s.c. xenografts of human glioblastoma (D54) in athymic mice increased to five times their initial volume at a median of 7.4 days in control animals, while tumor regression occurred in 12 of 12 animals treated with MDL101731 (100 mg/kg, i.p., two times/week) during 22 days of treatment (P < 0.0001). Intracerebral implants of D54 carried a median survival of 20 days in control animals, whereas animals receiving MDL101731 (100 mg/kg, i.p., two times/week, days 10-35) had a median survival of 46.5 days (P < 0.0001). Intracerebral xenografts of SK-N-MC in athymic mice resulted in a median survival of 23 days in control animals and 26 days in animals treated with carmustine (1,3-bis(2-chloroethyl)-1-nitrosourea 20 mg/kg/week, i.v. x 2; difference not significant). There was 90% survival in animals treated with MDL101731 (200 mg/kg, i.v., two times/week, days 7-35) up to 90 days after implant. These studies indicate that MDL101731 has potent antiproliferative activity against human malignant brain tumors.
Piepmeier
J M
JM
Department of Surgery/Neurosurgery, Yale University School of Medicine, New Haven, Connecticut 06520-8039, USA.
Rabidou
N
N
Schold
S C
SC
Bitonti
A J
AJ
Prakash
N J
NJ
Bush
T L
TL
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D001932:Brain Neoplasms / Q000188:drug therapy* / Q000201:enzymology; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005909:Glioblastoma / Q000188:drug therapy* / Q000201:enzymology; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D012262:Ribonucleoside Diphosphate Reductase / Q000037:antagonists & inhibitors*; D014183:Transplantation, Heterologous
D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D003841:Deoxycytidine; D012262:Ribonucleoside Diphosphate Reductase; C086432:tezacitabine