The molecular perspective: l-asparaginase.

The Oncologist 2005;10:238–239 www.TheOncologist.com Correspondence: David S. Goodsell, Ph.D., Associate Professor, The Scripps Research Institute, Department of Molecular Biology, 10550 North Torrey Pines Road, La Jolla, California 92037, USA. Telephone: 858-784-2839; Fax: 858-784-2860; e-mail: [email protected] Website: http://www.scripps.edu/pub/goodsell Received January 5, 2005; accepted for publication January 5, 2005. ©AlphaMed Press 1083-7159/2005/$12.00/0 With chemotherapy, we search for weaknesses in cancer cells and attack them where they are most vulnerable. Since cancer cells are dividing at an abnormally fast rate, many drugs target the processes of cell division. Cancer cells often communicate (or do not communicate) in odd ways, which provides other sensitive spots for treatment. The best drugs are those that attack features that are unique to cancer cells. We rarely reach this ideal, but with L-asparaginase, we get close. Our cells require a steady supply of the amino acid asparagine to build proteins. Most cells use the enzyme asparagine synthetase (Fig. 1, top) to make their own asparagine. The enzyme takes aspartate and adds an amine, forming the characteristic amide group of asparagine. Thus, most cells can make their own supplies of asparagine and do not need to obtain it in their diet. Some blood cells, however, rely instead on the blood for their supply of asparagine, Fundamentals of Cancer Medicine The Oncologist