Alpha Folate Receptor Mediated GARFTase Inhibitors as Selective Antitumor Agents

Summary

Principal Investigator: A Gangjee
Abstract: DESCRIPTION (provided by applicant): One of the major hurdles in cancer chemotherapy is the inability of the agent to selectively target tumor cells. The over expression of the FR-alpha on the surface of a number of tumors including ovarian, endometrial, kidney, lung, mesothelioma, breast and brain and FR-beta on the surface of myeloid leukemia has prompted the development of folic acid and the pteroyl moiety as selective targeting agents to FR-alpha expressing tumors. Thus, conjugates of folic acid and pteroates have been used to selectively deliver toxins, liposomes, imaging and cytotoxic agents to FR-alpha expressing tumors with a high degree of success. The process of utilizing a cytotoxic conjugate with the folic acid or pteroyl moiety as an antitumor agent requires the additional step of cleavage of the conjugate. This cleavage needs to occur selectively inside the tumor cell to release the cytotoxic agent. Premature release of the cytotoxic agent abrogates selectivity and leads to toxicity. The design of a cytotoxic agent that itself selectively targets the FR-alpha and is not appreciably taken up by the RFC would afford highly selective agents against FR-alpha expressing tumors without serious toxicity. We have recently discovered two compounds, AAG366 and AAG344 that are unique and are inhibitors of glycinamide ribonucleotide formyltransferase (GARFTase), are poorly taken up by the RFC and potently inhibits the growth of FR-alpha expressing KB tumor cells with IC50 values of 2.5 and 2.9 nM respectively. AAG366 and AAG344 are remarkable 100-345-fold more inhibitory to tumor cells expressing the FR-a compared to cells that do not express the FR-alpha. The Specific Aims of this proposal are: 1) to synthesize analogs of AAG366 and AAG344 to provide a structure-activity relationship (SAR) study to optimize the antitumor activity and the inhibitory activity against GARFTase as well as the high affinity binding and uptake by FR-alpha;2) to test the analogs for cytotoxicity in isogenic (CHO, KB, SKOV3, OVAR3, CCRF-CEM) cell line models with established differences in FR-alpha, RFC and folylpolyglutamate synthetase, to identify the molecular targets by nucleoside and aminoimidazole carboxamide protection from cytotoxicity by in situ metabolic labeling with radiolabeled (glycine, formate) biosynthetic precursors to determine affinities for FR binding, and to determine the inhibition of target enzyme GARFTase and other folate metabolizing enzymes by studies with isolated enzymes;3) to evaluate the in vivo antitumor activity of AAG366, AAG344 and selected analogs against FR-alpha expressing tumors. This study will provide a comprehensive SAR and should afford optimized analogs with increased antitumor activity against FR-alpha expressing tumors in vitro and in vivo. This study will also further define the mechanism(s) of action of these novel analogs and could provide agents to be used as monotherapy or in combination for clinical use with a different spectrum of antitumor activity and reduced toxicity than those currently in use.
Funding Period: ----------------2006 - ---------------2011-
more information: NIH RePORT

Top Publications

  1. pmc Role of lysine 411 in substrate carboxyl group binding to the human reduced folate carrier, as determined by site-directed mutagenesis and affinity inhibition
    Yijun Deng
    Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E Warren Avenue, Detroit, MI 48201, USA
    Mol Pharmacol 73:1274-81. 2008
  2. pmc Synthesis and discovery of high affinity folate receptor-specific glycinamide ribonucleotide formyltransferase inhibitors with antitumor activity
    Yijun Deng
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
    J Med Chem 51:5052-63. 2008
  3. pmc Functional loss of the reduced folate carrier enhances the antitumor activities of novel antifolates with selective uptake by the proton-coupled folate transporter
    Sita Kugel Desmoulin
    Graduate Program in Cancer Biology and Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan, USA
    Mol Pharmacol 82:591-600. 2012
  4. pmc The human proton-coupled folate transporter: Biology and therapeutic applications to cancer
    Sita Kugel Desmoulin
    Cancer Biology Graduate Program in Cancer Biology, Department of Oncology, Wayne State University School of Medicine Detroit, MI USA
    Cancer Biol Ther 13:1355-73. 2012
  5. pmc Therapeutic targeting malignant mesothelioma with a novel 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate via its selective uptake by the proton-coupled folate transporter
    Christina Cherian
    Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201, USA
    Cancer Chemother Pharmacol 71:999-1011. 2013
  6. pmc Synthesis and biological activity of a novel series of 6-substituted thieno[2,3-d]pyrimidine antifolate inhibitors of purine biosynthesis with selectivity for high affinity folate receptors over the reduced folate carrier and proton-coupled folate transpo
    Yijun Deng
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
    J Med Chem 52:2940-51. 2009
  7. pmc Synthesis and antitumor activity of a novel series of 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate inhibitors of purine biosynthesis with selectivity for high affinity folate receptors and the proton-coupled folate transporter over the reduc
    Lei Wang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA
    J Med Chem 53:1306-18. 2010
  8. pmc Targeting the proton-coupled folate transporter for selective delivery of 6-substituted pyrrolo[2,3-d]pyrimidine antifolate inhibitors of de novo purine biosynthesis in the chemotherapy of solid tumors
    Sita Kugel Desmoulin
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
    Mol Pharmacol 78:577-87. 2010
  9. pmc Design, synthesis, biological evaluation and X-ray crystal structure of novel classical 6,5,6-tricyclic benzo[4,5]thieno[2,3-d]pyrimidines as dual thymidylate synthase and dihydrofolate reductase inhibitors
    Xin Zhang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
    Bioorg Med Chem 19:3585-94. 2011
  10. pmc Synthesis, biological, and antitumor activity of a highly potent 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate inhibitor with proton-coupled folate transporter and folate receptor selectivity over the reduced folate carrier that inhibits β-gl
    Lei Wang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh 15219, Pennsylvania 15282, United States
    J Med Chem 54:7150-64. 2011

Detail Information

Publications12

  1. pmc Role of lysine 411 in substrate carboxyl group binding to the human reduced folate carrier, as determined by site-directed mutagenesis and affinity inhibition
    Yijun Deng
    Developmental Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E Warren Avenue, Detroit, MI 48201, USA
    Mol Pharmacol 73:1274-81. 2008
    ..An unmodified alpha-carboxylate is required for high-affinity substrate binding to RFC, whereas the gamma-carboxyl is not essential...
  2. pmc Synthesis and discovery of high affinity folate receptor-specific glycinamide ribonucleotide formyltransferase inhibitors with antitumor activity
    Yijun Deng
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
    J Med Chem 51:5052-63. 2008
    ..The combined properties of selective FR targeting, lack of RFC transport, and GARFTase inhibition resulting in potent antitumor activity are unprecedented and warrant development of these analogues as antitumor agents...
  3. pmc Functional loss of the reduced folate carrier enhances the antitumor activities of novel antifolates with selective uptake by the proton-coupled folate transporter
    Sita Kugel Desmoulin
    Graduate Program in Cancer Biology and Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan, USA
    Mol Pharmacol 82:591-600. 2012
    ..Thus, solid tumor-targeted antifolates with PCFT-selective cellular uptake should have enhanced activities toward tumors lacking RFC function, reflecting contraction of THF cofactor pools...
  4. pmc The human proton-coupled folate transporter: Biology and therapeutic applications to cancer
    Sita Kugel Desmoulin
    Cancer Biology Graduate Program in Cancer Biology, Department of Oncology, Wayne State University School of Medicine Detroit, MI USA
    Cancer Biol Ther 13:1355-73. 2012
    ....
  5. pmc Therapeutic targeting malignant mesothelioma with a novel 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate via its selective uptake by the proton-coupled folate transporter
    Christina Cherian
    Department of Oncology, Wayne State University School of Medicine, Detroit, MI 48201, USA
    Cancer Chemother Pharmacol 71:999-1011. 2013
    ....
  6. pmc Synthesis and biological activity of a novel series of 6-substituted thieno[2,3-d]pyrimidine antifolate inhibitors of purine biosynthesis with selectivity for high affinity folate receptors over the reduced folate carrier and proton-coupled folate transpo
    Yijun Deng
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan 48201, USA
    J Med Chem 52:2940-51. 2009
    ....
  7. pmc Synthesis and antitumor activity of a novel series of 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate inhibitors of purine biosynthesis with selectivity for high affinity folate receptors and the proton-coupled folate transporter over the reduc
    Lei Wang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, USA
    J Med Chem 53:1306-18. 2010
    ..5 log kill, 1/5 cures) and advanced (3.7 log kill, 4/5 complete remissions) stage tumors. Our results demonstrate potent in vitro and in vivo antitumor activity for 1 due to selective transport by FRs and PCFT over RFC...
  8. pmc Targeting the proton-coupled folate transporter for selective delivery of 6-substituted pyrrolo[2,3-d]pyrimidine antifolate inhibitors of de novo purine biosynthesis in the chemotherapy of solid tumors
    Sita Kugel Desmoulin
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
    Mol Pharmacol 78:577-87. 2010
    ..Furthermore, they establish the feasibility of selective chemotherapy drug delivery via PCFT over RFC, a process that takes advantage of a unique biological feature of solid tumors...
  9. pmc Design, synthesis, biological evaluation and X-ray crystal structure of novel classical 6,5,6-tricyclic benzo[4,5]thieno[2,3-d]pyrimidines as dual thymidylate synthase and dihydrofolate reductase inhibitors
    Xin Zhang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, Pittsburgh, PA 15282, USA
    Bioorg Med Chem 19:3585-94. 2011
    ....
  10. pmc Synthesis, biological, and antitumor activity of a highly potent 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolate inhibitor with proton-coupled folate transporter and folate receptor selectivity over the reduced folate carrier that inhibits β-gl
    Lei Wang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh 15219, Pennsylvania 15282, United States
    J Med Chem 54:7150-64. 2011
    ....
  11. pmc Therapeutic targeting of a novel 6-substituted pyrrolo [2,3-d]pyrimidine thienoyl antifolate to human solid tumors based on selective uptake by the proton-coupled folate transporter
    Sita Kugel Desmoulin
    Graduate Program in Cancer Biology, Wayne State University School of Medicine, Detroit, Michigan, USA
    Mol Pharmacol 80:1096-107. 2011
    ..Our findings suggest exciting new therapeutic possibilities to selectively deliver novel antifolate drugs via transport by PCFT over RFC by exploiting the acidic tumor microenvironment...
  12. pmc Synthesis and biological activity of 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl regioisomers as inhibitors of de novo purine biosynthesis with selectivity for cellular uptake by high affinity folate receptors and the proton-coupled folate transporter
    Lei Wang
    Division of Medicinal Chemistry, Graduate School of Pharmaceutical Sciences, Duquesne University, 600 Forbes Avenue, Pittsburgh, Pennsylvania 15282, United States
    J Med Chem 55:1758-70. 2012
    ..Compounds 7 and 8 were potent nanomolar inhibitors of KB and IGROV1 human tumor cells with complete selectivity for FRα and PCFT over RFC...