Enzyme Inhibitor That May Slow Cancer Growth

Enzyme Inhibitor That May Slow Cancer Growth Developed by U of I Scientist
This article talks about research on an enzyme inhibitor that affects an enzyme called betaine-homocysteine-S-methyltransferase (BHMT). BHMT catalyzes a reaction that results in the production of methionine from homocysteine. Methionine is an amino acid that is essential for many biological processes, and cancer cells require high levels of this amino acid. Tim Garrow, who researched this topic, says that the ability to lower methionine levels in the body could allow us to selectively inhibit cancer growth. Garrow first became interested in BHMT when he realized that high levels of homocysteine lead to several diseases, such as thrombosis. 


By studying BHMT's crystal structure, Garrow was able to design inhibitors for it. These inhibitors were injected into the abdomens of mice, and results showed that this caused them to have increased homocysteine levels. This shows that the inhibitors did prevent the enzyme from catalyzing the homocysteine to methionine reaction. Garrow also stated that using the BHMT inhibitor alongside another cancer drug could cause the other drug to have a greater impact, as the availability of methionine to the cancer cells is decreased.


However, elevated homocysteine levels can also have a negative impact on the body, such as leading to vascular diseases. Garrow claims that the BHMT inhibitor would most likely be used for short periods of time, while vascular diseases take a long time to develop. There is also another potential use for BHMT inhibitors. One of the substrates of BHMT is betaine, which donates a methyl group to homocysteine to form methionine. Betaine also functions in regulating cells' water content, so BHMT inhibitors might be useful in preventing unwanted water loss in the body. This article shows an interesting application of man-made enzyme inhibitors for the purpose of slowing cancer growth.