Studies From New Field of Pharmacogenomics Point Toward Future of “Individualized” Cancer Treatment

Last Updated: Aug. 1, 2003

At the 94th Annual Meeting of the American Association for Cancer Research in July 2003, cancer researchers discussed the emerging uses of genes in anti-cancer drug development. Two sub studies of genomics (the study of genes that led to the mapping of the human genome) were highlighted: proteomics and pharmacogenomics.

Advances in clinical proteomics
Proteomics is the study of protein profiles, which include their location, structure and function, and abundance. Human genes are responsible for the production of proteins, which are crucial to normal cell function. Because of gene mutations in cancer cells, the protein profile may become abnormal. Dr. Lance Liotta, of the National Cancer Institute in Bethesda, Maryland, reviewed how advances in proteomics may revolutionize the detection and treatment of cancer. Laboratory studies are ongoing to identify the protein profiles that indicate the presence of cancer. Moreover, clinical trials are under way to test the effectiveness of proteomics at predicting therapeutic outcomes.

Pharmacogenomics in anti-cancer drug development
Pharmacogenomics is the study of how an individual’s genetic inheritance affects the body’s response to drugs. Though other factors, such as diet, age, lifestyle and health status, can influence response to medications, understanding an individual’s genetic makeup may hold the key to individualizing therapy for the best effect.

Dr. Paul Workman of the Institute of Cancer Research in Sutton, United Kingdom, stressed that pharmacogenomics may speed up movement toward genetically-based individualized cancer treatment. He pointed out several applications of pharmacogenomics and gene expression profiling in cancer research. A cancer’s behavior is determined by the expression of thousands of genes, and gene expression profiling could potentially allow a cancer’s behavior and the clinical consequences to be predicted.

Dr. Eileen Dolan, of the University of Chicago in Illinois, reviewed how pharmacogenetics will play an important role in anti-cancer drug development. Pharmacogenetics is the study of inherited differences in how a drug is broken down in the body and how the body responds to the drug. Finding gene variations that affect drug response is very complex and involves analysis of millions of variations in DNA, which makes up genes.

Dr. Howard McLeod, of the Washington University School of Medicine in St. Louis, Missouri, explained how pharmacogenomics will affect the future design of clinical trials. He pointed out two ways that pharmacogenomics could be used to design these trials: (1) to avoid side effects of treatment by identifying patients with a particular genetic make-up who are likely to have side effects, and (2) to identify target populations (groups of patients) for therapy development. These target populations include either patients whose genetic profile shows either (1) they will have minimal benefit from standard anti-cancer treatment or (2) they may have a chance of better outcome with a certain treatment. For example, results of a clinical trial in a small number of patients with colorectal cancer showed that some people responded better than others based on the patient’s genetic profile.

We Have Answers Do you have medical questions or need help finding a doctor? The experts at Columbia St. Mary's and Advanced Healthcare can help. Click here.