title: Discovery of 5-substituted pyrrolo[2,3-d]pyrimidine antifolates as dual-acting inhibitors of glycinamide ribonucleotide formyltransferase and 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase in de novo purine nucleotide biosynthesis: implications of inhibiting 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase to ampk activation and antitumor activity.
abstract: We synthesized 5-substituted pyrrolo[2,3-d]pyrimidine antifolates (compounds 5-10) with one-to-six bridge carbons and a benozyl ring in the side chain as antitumor agents. Compound 8 with a 4-carbon bridge was the most active analogue and potently inhibited proliferation of folate receptor (FR) α-expressing Chinese hamster ovary and KB human tumor cells. Growth inhibition was reversed completely or in part by excess folic acid, indicating that FRα is involved in cellular uptake, and resulted in S-phase accumulation and apoptosis. Antiproliferative effects of compound 8 toward KB cells were protected by excess adenosine but not thymidine, establishing de novo purine nucleotide biosynthesis as the targeted pathway. However, 5-aminoimidazole-4-carboxamide (AICA) protection was incomplete, suggesting inhibition of both AICA ribonucleotide formyltransferase (AICARFTase) and glycinamide ribonucleotide formyltransferase (GARFTase). Inhibition of GARFTase and AICARFTase by compound 8 was confirmed by cellular metabolic assays and resulted in ATP pool depletion. To our knowledge, this is the first example of an antifolate that acts as a dual inhibitor of GARFTase and AICARFTase as its principal mechanism of action.
authors.affiliation: Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Shermaine
authors.initials: S
authors.lastname: Mitchell-Ryan
authors.affiliation: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282.
authors.forename: Yiqiang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282.
authors.forename: Sudhir
authors.initials: S
authors.lastname: Raghavan
authors.affiliation: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282.
authors.forename: Manasa Punaha
authors.initials: MP
authors.lastname: Ravindra
authors.affiliation: Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Ave, Detroit, MI 48201.|Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Eric
authors.initials: E
authors.lastname: Hales
authors.affiliation: Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Ave, Detroit, MI 48201.|Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Steven
authors.initials: S
authors.lastname: Orr
authors.affiliation: Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Ave, Detroit, MI 48201.|Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Christina
authors.initials: C
authors.lastname: Cherian
authors.affiliation: Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Ave, Detroit, MI 48201.|Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.|Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Zhanjun
authors.initials: Z
authors.lastname: Hou
authors.affiliation: Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 East Warren Ave, Detroit, MI 48201.|Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201.|Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201.
authors.forename: Larry H
authors.initials: LH
authors.lastname: Matherly
authors.affiliation: Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, PA 15282.
authors.forename: Aleem
authors.initials: A
authors.lastname: Gangjee
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D000818:Animals; D000970:Antineoplastic Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D016466:CHO Cells; D049109:Cell Proliferation / Q000187:drug effects; D003412:Cricetulus; D004305:Dose-Response Relationship, Drug; D055808:Drug Discovery; D004354:Drug Screening Assays, Antitumor; D004791:Enzyme Inhibitors / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D005493:Folic Acid Antagonists / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D019877:Hydroxymethyl and Formyl Transferases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007624:KB Cells; D008958:Models, Molecular; D015394:Molecular Structure; D011685:Purine Nucleotides / Q000096:biosynthesis*; D011743:Pyrimidines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D011758:Pyrroles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D013329:Structure-Activity Relationship
chemical_list: D000970:Antineoplastic Agents; D004791:Enzyme Inhibitors; D005493:Folic Acid Antagonists; D011685:Purine Nucleotides; D011743:Pyrimidines; D011758:Pyrroles; C450639:Pyrrolo(2,3-d)pyrimidine; D019877:Hydroxymethyl and Formyl Transferases; D055372:AMP-Activated Protein Kinases