Prostate cancer is the most common male-specific form of cancer in the U.K. Current treatments for the aggressive disease by androgen-deprivation therapy gives a rapid initial response, but the disease ultimately progresses into an androgen-independent state for which there are no effective treatments. α-Methylacyl-CoA racemase (AMACR, P504S) is an enzyme which is involved in metabolism of branched-chain fatty acids and the pharmacological activation of some NSAID drugs, such as Ibuprofen and most other ‘profens’. AMACR is over-expressed in prostate cancer and some other cancers, including colon and breast cancers. Reduction of AMACR protein levels inhibits proliferation of prostate cancer cells and restores the requirement for androgens for growth. Although the exact role of AMACR in prostate cancer progression is currently unknown, several other experiments show that AMACR is functionally important for prostate cancer proliferation, validating it as a drug target.There is no convenient high-throughput assay for AMACR and as a result only a few inhibitors have been reported to date. This thesis reports a study on whether other reactions can be catalysed by AMACR. 2-Methyl-3-enoyl-CoA esters are good substrates of AMACR but do not undergo double bond migration, while 2-methyl-2-enoyl-CoA esters are not converted to products. Acyl-CoA esters that contain a fluorine atom at carbon-3 undergo a fluoride elimination reaction to give 2-methyl-2-enoyl-CoA esters. This elimination reaction was investigated for use in the development of a high-throughput assay. A fluorescent binding assay, which can be adapted for the screening of large libraries of compounds, was developed and several known and novel inhibitors were tested. Finally, metabolism of mandelic acid was investigated. It was shown that chiral inversion of mandelic acid in humans proceeds via a different pathway to Ibuprofen and related drugs, in contrast with previous reports.
|Date of Award
|25 Mar 2015
|Prostate Cancer UK
|Matthew Lloyd (Supervisor) & Tim Woodman (Supervisor)