Cancer Biomarkers Could Help Guide Treatment

New blood or biopsy tests predict patients' response to therapy, experts say.

Wednesday, April 18, 2007; 12:00 AM

Copyright © 2007 ScoutNews, LLC. All rights reserved.

WEDNESDAY, April 18 (HealthDay News) -- New biomarkers could help doctors predict how individual cancer patients will respond to drug or radiation therapy, new research suggests,

The findings were detailed in a number of studies presented Wednesday at the annual meeting of the American Association for Cancer Research in Los Angeles.

Being able to determine how a patient will respond to specific cancer therapies should boost cancer treatment, experts said.

In one study, researchers at Lawrence Berkeley National Laboratory identified gene expression signatures that could serve as biomarkers to predict how a woman will respond to the breast cancer drugs lapatinib and CI-1040.

"Individuals respond differently to different therapeutics because there are substantial differences in the spectrum of genetic, biological and epigenetic (non-inherited) characteristics between breast cancers," Joe W. Gray, director of the Life Sciences Division at Lawrence Berkeley National Laboratory, explained in a prepared statement.

"We need better ways to identify how we can best tailor existing therapies to individuals and how to target experimental agents," Gray said.

In another study, French researchers said they found that mutations in the KRAS oncogene could predict a lack of response to the drug cetuximab in colorectal cancer patients. For people with this mutation, the drug is likely to be ineffective and could even harm them.

"Because of variety of different effective agents may now be available for any given type of cancer, deciding which treatment regimen is likely to be the most effective and the least toxic is more complicated than ever," Dr. Pierre Laurent-Puig, a professor of oncology at the University of Paris-Descartes, said in a prepared statement.

"Characterizing the factors that are predictive of toxicity and efficacy could lead to significant improvement in both the quality of treatment and outcomes," he said.

A third study by Vanderbilt University researchers identified 44 peptides (protein fragments) that can be used to determine response to tyrosine kinase inhibitor drug therapy -- combined with radiation therapy -- in patients battling lung or brain cancer.