Role of DNA-repair protein suggests strategy to knock out cancer

Repair proteins (bright green areas) are inhibited from gathering at sites of DNA damage.To remain healthy, all cells must quickly mend any breaks that arise in their DNA strands. But cancer cells are particularly dependent on a process called homologous recombination to repair DNA and stay alive. Now researchers at Washington University School of Medicine in St. Louis have identified a protein with a role in homologous recombination, and the discovery could be exploited as part of a two-pronged treatment strategy to kill cancer cells by eliminating their ability to repair DNA.

Profile of tumor genes shows need for individualized chemotherapy

Genes respond to chemo drugOncologists aren’t sure exactly why patients with the same cancer often respond very differently to the same treatment, but a growing body of evidence suggests the answer lies somewhere in the genes. Now researchers at the School of Medicine have become the first to profile the activity of whole sets of genes involved in processing chemotherapeutic drugs.

Profile of tumor genes shows need for individualized chemotherapy

A look at the activity of 24 genes in 52 patients as those genes respond to the chemotherapy drug 5-fluorourancilOncologists aren’t sure exactly why patients with the same cancer often respond very differently to the same treatment, but a growing body of evidence suggests the answer lies somewhere in the genes. Now researchers at Washington University School of Medicine in St. Louis have become the first to profile the activity of whole sets of genes involved in processing chemotherapeutic drugs.

Avoiding esophagitis

Lung cancer tumor to be treated with radiation.More than half of the lung cancer patients who receive radiation treatment for their illness develop a painful swelling and inflammation in the esophagus known as esophagitis. Although treating the lung cancer is the top priority for doctors, researchers at Washington University School of Medicine in St. Louis hope to lower the risk of this unpleasant side effect. They have quantified risk factors for esophagitis, linking it to the amount of radiation a patient’s esophagus receives and to simultaneous chemotherapy. The findings mean it may be possible to predict and potentially avoid esophagitis, according to Jeffrey D. Bradley, M.D., assistant professor of radiation oncology and lead author of a paper published recently in the International Journal of Radiation Oncology, Biology, Physics.

Bioluminescent agent reveals drug-resistant cancer in animal models

A protein known as Pgp has pumped an imaging agent that glows away from a tumor on the lower right of this mouse.Oncologists dread the appearance of MDR1 P-glycoprotein (Pgp), a protein found on the surface of drug-resistant cancers that pumps away chemotherapy treatments. Now researchers have discovered Pgp also rids cells of a bioluminescent agent used in imaging research. According to David Piwnica-Worms, M.D., Ph.D., professor of molecular biology and pharmacology and of radiology and director of Washington University’s Molecular Imaging Center, the finding means scientists now have a direct, real-time method for assessing treatments designed to block drug resistance in animal models of cancer because if Pgp is present, the imaging agent is expelled from cells, it’s also likely that those cells will be resistant to chemotherapy. On the other hand, the discovery also means basic researchers, who make frequent use of the luminescent imaging agent (derived from a sea pansy or soft coral), have to make sure that what they are seeing isn’t being affected by interactions with Pgp.