Defense Date

11-19-2024

Graduation Date

Winter 12-20-2024

Availability

One-year Embargo

Submission Type

thesis

Degree Name

MS

Department

Medicinal Chemistry

School

School of Pharmacy

Committee Chair

Aleem Gangjee

Committee Member

Patrick T. Flaherty

Committee Member

Marc Harrold

Keywords

Antifolates, Pemetrexed, Methotrexate, Dose-limiting toxicity, chemotherapeutics agents

Abstract

In cancer chemotherapy, the currently marketed antifolates have two major disadvantages: dose-limiting toxicities to normal tissues and susceptibility to drug resistance. These are due to their major transport by the ubiquitously expressed transporter and mutagenesis in enzymes present in cancer cells. This thesis describes an introduction, background, and research progress in antimetabolites-antifolates designed to multi-target (a) one-carbon metabolism and de novo nucleotide synthesis pathway and (b) target overexpressed transporter in cancer cells for selective tumor-targeting.

Cancer cells transport folate through three transporters: ubiquitously expressed reduced folate carrier (RFC), limitedly expressed proton-coupled folate transporter (PCFT), and folate receptors (FRs). The research strategies that have developed drugs that target PCFT and/or FRs transporter, which could only minimize the dose-limiting toxicity issue through specificity for cancer cells. To address the mutagenesis/ drug resistance issue, one must target multiple enzymes such that the cancer cells can not simultaneously mutate multiple targets. Moreover, in cancer cells, one-carbon metabolism enzymes supported by folate metabolism are known to be upregulated and serve to activate multiple biosynthetic processes, including de novo purine and thymidine synthesis and homocysteine remethylation, required for their proliferation and survival. Thus, the next valid step is to design and synthesize compounds that can address mutagenesis/drug resistance and toxicity issues by targeting multiple one-carbon metabolism enzymes along with transport specificity in cancer cells.

Pemetrexed (PMX), initially named as a multitargeted antifol (MTA) and now with the trade name Alimta, was approved for several cancers, including non-small-cell lung cancer and mesothelioma, and has three disadvantages: (1) Its major transport is by the ubiquitously expressed RFC; (2) It is dependent on its polyglutamylation for potency, and (3) It has developed resistance due to mutagenesis in folypolygultamate synthase (FPGS), thymidylate synthase (TYMS) and dihydrofolate reductase (DHFR). The work in this thesis involves the design and the development of a part of a pipeline of pyrrolo-pyrimidine antifolates that are superior to PMX as they circumvent the disadvantages of PMX.

Language

English

Available for download on Saturday, January 31, 2026

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