An Examination of The Specific Functions of Three Cancer Drugs (Methotrexate, Fluorouracil, And Taxol) and Their Expected Effects on Gene Expression

An Examination of The Specific Functions of Three Cancer Drugs (Methotrexate, Fluorouracil, And Taxol) and Their Expected Effects on Gene Expression

Cancer is a term used to define many diseases in which a group of cells exhibit uncontrolled growth, invasion, and sometimes metastasis. In this literature review project, the mechanisms of action for three drugs used to treat cancer by inhibiting cell division: Ledertrexate (methotrexate), Fluorouracil (adrucil), and Paclitaxel (taxol) are examined. Methotrexate inhibits an enzyme called dihydrofolate reductase (DHFR) that catalyses the conversion of dihydrofolate to folic acid, needed for the synthesis of the nucleoside thymidine, and also purines which are required for DNA synthesis. Fluorouracil functions as a thymidylate synthase inhibitor by stopping the synthesis of the pyrimidine, thymidine, a nucleotide needed for DNA replication. Fluorouracil competes with pyrimidines by entering the cell, forcing the cell cycle to stop and initiatingapoptosis by inhibiting the cell‘s ability to synthesize DNA. Taxol interferes with the normal function of microtubule breakdown by binding to the β (beta) subunit of tubulin.When taxol binds to microtubules, they become locked in place, inhibiting their ability to disassemble. This affects cell function because the shortening and lengthening of microtubules is required for the transportation of cellular components and movement of chromosomes during mitosis. Taxol also induces apoptosis in cancer cells by binding to an apoptosis stopping protein, Bcl-2. This literature review is designed to provide the background for a potential honors research thesis proposal to examine changes in gene expression of yeast cells (as a model eukaryotic organism) exposed to these three drugs.