Research Briefs — September 2009

Apoptosis, the process by which cells die in an orderly, programmed fashion, is central to the health of organisms. When it malfunctions, however, the process can be a major cause of disease.

Enzymes called caspases are vital to apoptosis, but they are controlled by a large number of factors that activate and inhibit them. Identifying and characterizing all the players poses a complex puzzle for researchers.

Dr. John Abrams, professor of cell biology, uses RNA interference a technique that employs tiny segments of genetic material to systematically “knock down,” or silence, genes throughout the entire genome of the fruit fly Drosophila. In a recent study published in Nature, his research group used this technique to identify 13 genes necessary for apoptosis.

The scientists focused on one gene, dubbed Tango7, because its action was particularly robust, and it acted on a second gene that has a counterpart in human apoptosis.

Other UT Southwestern researchers from cell biology involved in the study were Dr. Po Chen, assistant professor, and graduate student Nichole Link.

— Aline McKenzie

A new treatment for removing the damaged lining in Barret’s esophagus works better than the typical therapy and reduces the rate of disease progression to cancer,
UT Southwestern researchers and their colleagues at 18 other institutions have found in a national study.

Among the treatments for dysplasia in Barrett’s esophagus a condition in which the reflux of gastric juice damages the lining of the esophagus are invasive procedures such as esophagectomy.

Dr. Stuart Spechler, professor of internal medicine, is an author of the work that appeared in The New England Journal of Medicine. He and his colleagues found that radiofrequency ablation eradicated the damaged esophagus lining in 77 percent of patients, compared with only 2 percent of patients who received a sham treatment. For patients with high-grade dysplasia in Barrett’s esophagus, a condition that frequently progresses to cancer, the researchers found that radiofrequency ablation eradicated the dysplasia in 81 percent, compared with 19 percent in the sham treatment group.

Other UT Southwestern researchers involved in the study included Dr. Ali Siddiqui, assistant professor of internal medicine, and Dr. Rhonda Souza, associate professor of internal medicine.

— LaKisha Ladson