April 12, 2007
Scientists Discover Chemotherapy Sensitive Genes
Scientists have identified a set of genes that appear more sensitive to chemotherapy drugs and it is believed the discovery could lead the way to less toxic cancer therapies.
Researchers at UT Southwestern Medical Center used a quick-screen technology to isolate 87 genes that seem to affect how sensitive human cancer cells are to certain chemotherapy drugs. The finding may allow a lower dose of chemotherapy drugs without compromising effectiveness.
When the researchers blocked the action of the 87 genes inside isolated lung-cancer cells, they found that those cells were up to 10,000 times more sensitive to the chemotherapy drug paclitaxel, also known as Taxol.
The researchers used small molecules, called small interfering RNAs, to block the activity of individual genes. The researchers examined the survival of the lung cancer cells in order to determine which genes were involved in affecting the cells' sensitivity to the drug. Over 20,000 genes in human lung-cancer cells were tested in this way.
The advantage of this technique is that it is very fast and genes can be tested in a short time period.
The researchers re-tested six genes that showed the most dramatic effect with Taxol and tried the same test using the chemotherapy drugs Navelbine and Gemzar, but the results were not as dramatic as those seen for Taxol.
The scientists said the current study tested only isolated cancer cells, so further studies will be needed to determine whether blocking the genes in living animals has the same effect.