UPCI Researchers Present Early Findings of Cancer Studies at AACR 101st Annual Meeting
WASHINGTON, D.C., April 21, 2010 – The potential of DNA repair proteins as biomarkers to predict the success of certain treatments against head and neck cancers, the use of anti-estrogen drugs against lung cancer, and many other studies conducted by researchers at the University of Pittsburgh Cancer Institute (UPCI) will be highlighted during the American Association for Cancer Research 101st Annual Meeting, April 17 to 21, in Washington, D.C.
DNA Repair Proteins and Cancer Treatment
Laura Niedernhofer, M.D., Ph.D., associate professor of microbiology and molecular genetics, University of Pittsburgh School of Medicine, will present her efforts to use proteins in the DNA repair pathways as markers to predict the effectiveness of certain cancer drugs.
“The non-surgical treatment of head and neck cancers uses drugs and radiation therapy that work by causing DNA damage,” she explained. “But about half of these patients have tumors that are resistant to these therapies. That could be because some people have more repair proteins that act quickly to fix what’s broken by the treatments, allowing the cancer cells to survive.”
Dr. Niedernhofer’s team analyzed tumor samples from patients with head and neck cancers and found that those who had lower levels of a protein called XPF, which is an essential component of DNA repair pathways, tended to have better clinical outcomes than those whose XPF levels were high. The research is supported by a Specialized Program of Research Excellence (SPORE) grant in head and neck cancer from the National Cancer Institute and the National Institute of Environmental Health Sciences.
Anti-Estrogen Drugs and Lung Cancer
Jill M. Siegfried, Ph.D., professor of pharmacology, University of Pittsburgh School of Medicine, and co-director of the lung and thoracic malignancies program, UPCI, will present findings from a study that showed when compared to placebo, the aromatase inhibitor anastrazole, or Arimidex, reduced the number and size of lung tumors in mice bred to develop the cancer after exposure to a tobacco carcinogen. When fulvestrant, an anti-estrogen drug, was used in combination with anastrazole, tumor number decreased even more.
“Anti-estrogen drugs have been shown to be effective in preventing and treating breast tumors that carry estrogen receptors and the enzyme aromatase, which synthesizes estrogen,” Dr. Siegfried said. “We wanted to see if that held true for lung tumors with estrogen receptors and aromatase expression. Our results suggest that modifying estrogen signaling could be a beneficial approach for lung cancer treatment and prevention, as well.”
The study is supported by a SPORE grant in lung cancer, for which Dr. Siegfried is the principal investigator.
Dr. Siegfried and her UPCI colleagues will have posters at the meeting that share preliminary findings from other ongoing projects, including therapeutic drug targets to slow the progression of lung tumors (Abstract 4123); and the first study to evaluate whether variants in the DNA repair gene PARP1 are associated with the risk of developing smoking-related non-small cell lung cancer (Abstract LB-414).
Novel Drug Improves Bone Healing After Radiation Exposure, Inhibits Tumor Growth
Mice treated with the experimental drug JP4-039 before they were exposed to radiation healed better after bone injury than untreated animals. The drug also inhibited tumor growth, suggesting a potential role in cancer therapy. Abstract 1404
Poxvirus, Immune Suppressing Drugs Work to Kill Tumor Cells
A cocktail of drugs most often used to suppress the immune system in transplant patients significantly improves the delivery of the cancer-killing poxvirus to tumor cells despite pre-existing immunity to the virus. According to researchers, the drugs commonly given to liver transplant recipients suppress the immune system to stop it from eliminating poxvirus carried within cancer cells, allowing it to infect and kill other diseased cells in a mouse model. Abstract 1498
Stress Hormones Promote Resistance to Certain Type of Chemotherapy
Triple negative breast cancer (TNBC) is an aggressive form of breast cancer often associated with poorer overall patient prognosis. Typically, half of patients with TNBC do not respond to treatment because they become resistant. For the first time, UPCI researchers examined the role of stress hormones and paclitaxel, a chemotherapy often used to treat TNBC. Results showed that stress hormones promoted resistance to paclitaxel through modulation of several markers of TNBC drug resistance. Abstract 2579
Urine Screening May Lead to Earlier Cancer Detection
Screening urine instead of blood for certain cancer markers may lead to earlier detection of the disease. Researchers analyzed several sets of cancer markers present in the urine and blood of patients diagnosed with ovarian, pancreatic and breast cancers. Analyses showed that nearly all of the cancer indicators were detectable in urine. Additionally, differences in many of the protein marker levels between cancer patients and healthy controls were more apparent by urine screening than with the more traditional blood screening. Abstract 4567
Human Herpesvirus 8 Infection, Inflammation and IL-6 Polymorphism All Contribute to Increased Prostate Cancer Risk for Men of African Descent
In men of African descent, human herpesvirus 8 establishes a chronic infection, which causes chronic inflammation. The virus and inflammation, along with a variant or polymorphism in the IL-6 signaling receptor, may result in the increased prostate cancer risk for this population. Abstract 5726
About University of Pittsburgh Cancer Institute (UPCI)
As the only NCI-designated comprehensive cancer center in western Pennsylvania, UPCI is a recognized leader in providing innovative cancer prevention, detection, diagnosis, and treatment; bio-medical research; compassionate patient care and support; and community-based outreach services. UPCI investigators are world-renowned for their work in clinical and basic cancer research.