Genomic tests for better cancer treatment

According to the U.S. researchers, 80% accuracy in prediction of the most effective drug against a specific type of cancer is achieved by a new test that examines the genetic material of a patient’s tumour.

A group of researchers at Duke University in North Carolina report that this genomic test is useful in predicting the efficacy of not only a single drug against a particular cancer but also a combination of drugs.

The researchers reported in the journal Nature Medicine that they made use of a gene chip manufactured by Affymetrix, in their test on tumour samples from various patients with different cancers like leukemia, ovarian, breast and lung cancers. The first clinical trial on 120 breast cancer patients is planned for next year.

"With the new test, we think that physicians will be able to personalize chemotherapy in a way that should improve outcomes," said Dr. Anil Potti, an assistant professor of medicine in the Duke Institute for Genome Sciences & Policy who led the study.

"Over 400,000 patients in the United States are treated with chemotherapy each year, without a firm basis for which drug they receive," said genetics professor Joseph Nevins. "We believe these genomic tests have the potential to revolutionize cancer care by identifying the right drug for each individual patient," Nevins said in a statement.

"Importantly, we believe this research can improve the efficiency of chemotherapy without changing the drugs currently used in standard practice. Rather, the tests simply provide an approach to better selection within a repertoire of available drugs."

The messenger RNA is picked up from thousands of genes in the tumour with the help of the gene chip. A gene’s DNA code is translated into proteins by the messenger RNA. These proteins carry out the activities of the cell, thus signifying the activity of a particular gene within a cell.

This kind of testing is carried out to a certain extent to detect if the patient can go for so-called targeted therapies like Tarceva, Herceptin and other drugs. This study was carried out on old and less-specific cancer drugs like paclitaxel, topotecan and 5-fluorouracil.

The assay results of the study were compared with the actual results that the patient had with chemotherapy. 80% accuracy was obtained in the prediction of a specific drug or a combination of drugs against a tumour.

Josephine Querido of Cancer Research UK said: "Being able to predict who will respond to a chemotherapy drug and who will not is a hot topic for cancer researchers worldwide - it would allow doctors to identify which patients will benefit most from the treatment.

"The results presented in this study are very encouraging, and we hope approaches like these will soon be available in the clinic so that more patients will receive treatments that are right for them."

Source-Medindia
GYT