title: Single agents with designed combination chemotherapy potential: synthesis and evaluation of substituted pyrimido[4,5-b]indoles as receptor tyrosine kinase and thymidylate synthase inhibitors and as antitumor agents.
abstract: Combinations of antiangiogenic agents (AAs) with cytotoxic agents have shown significant promise in cancer treatment, and several such clinical trials are currently underway. We have designed, synthesized, and evaluated two compounds that each inhibit vascular endothelial growth factor receptor-2 (VEGFR-2) and platelet-derived growth factor receptor-beta (PDGFR-beta) for antiangiogenic effects and also inhibit human thymidylate synthase (hTS) for cytotoxic effects in single agents. The synthesis of these compounds involved the nucleophilic displacement of the common intermediate 5-chloro-9H-pyrimido[4,5-b]indole-2,4-diamine with appropriate benzenethiols. The inhibitory potency of both these single agents against VEGFR-2, PDGFR-beta, and hTS is better than or close to standards. In a COLO-205 xenograft mouse model, one of the analogs significantly decreased tumor growth (tumor growth inhibition (TGI) = 76% at 35 mg/kg), liver metastases, and tumor blood vessels compared with a standard drug and with control and thus demonstrated potent tumor growth inhibition, inhibition of metastasis, and antiangiogenic effects in vivo. These compounds afford combination chemotherapeutic potential in single agents.
authors.affiliation: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA. gangjee@duq.edu
authors.forename: Aleem
authors.initials: A
authors.lastname: Gangjee
authors.forename: Nilesh
authors.initials: N
authors.lastname: Zaware
authors.forename: Sudhir
authors.initials: S
authors.lastname: Raghavan
authors.forename: Michael
authors.initials: M
authors.lastname: Ihnat
authors.forename: Satyendra
authors.initials: S
authors.lastname: Shenoy
authors.forename: Roy L
authors.initials: RL
authors.lastname: Kisliuk
mesh_terms: D020533:Angiogenesis Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D002642:Chick Embryo; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008958:Models, Molecular; D009368:Neoplasm Transplantation; D011743:Pyrimidines / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D020797:Receptor, Platelet-Derived Growth Factor beta / Q000037:antagonists & inhibitors*; D013329:Structure-Activity Relationship; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D013940:Thymidylate Synthase / Q000037:antagonists & inhibitors*; D014183:Transplantation, Heterologous; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors*
chemical_list: D020533:Angiogenesis Inhibitors; D000970:Antineoplastic Agents; D007211:Indoles; D011743:Pyrimidines; D013438:Sulfhydryl Compounds; D013940:Thymidylate Synthase; D020797:Receptor, Platelet-Derived Growth Factor beta; D040301:Vascular Endothelial Growth Factor Receptor-2