Study shows EZH2 Boosts Creation of Ovarian Cancer Blood Vessels
Scientists at MD Anderson are conducting a study using siRNA-loaded nanoparticles to stifle EZH2, a member of a group of proteins known to repress gene expression associated with poor survival rates in cancer patients.
The protein also has been associated with the progression and spread of ovarian cancer as well as numerous other cancers, including bladder, breast, prostate, gastric and one type of cancer of the pharynx.
“We've discovered that EZH2 promotes tumor growth by shutting down genes that block formation of new blood vessels,” says study senior author Anil Sood, M.D., professor of gynecologic oncology and cancer biology and director of the Blanton-Davis Ovarian Cancer Research Program at MD Anderson. “Tumors treated with current anti-angiogenesis drugs eventually progress. This study presents a new mechanism for angiogenesis that opens the door for development of new treatment approaches.”
The study was funded by grants from the National Cancer Institute, the Ovarian Cancer Research Fund Inc., the U.S. Department of Defense, the Zarrow Foundation, the Marcus Foundation, the Betty Anne Asche Murray Distinguished Professorship, the Gynecologic Cancer Foundation/OCRF Ann Schreiber Ovarian Cancer Research grant, the Meyer and Ida Gordon Foundation, the National Institute of Child Health and Development, the GCF-Molly Cade Ovarian Cancer Research Grant and the Taiwan National Science Council.
New Breast Cancer Guidelines Needed for Mexican-origin Women
Specific prevention and education strategies are needed to address breast cancer in Mexican-origin women in this country, according to an MD Anderson study published online in the journal Cancer.
Among the Mexican-origin women with breast cancer surveyed, half were diagnosed before age 50, years earlier than the national average for non-Hispanic white women. This puts them outside U.S. Preventive Task Force guidelines that recommend screening begin at 50 for the general population. MD Anderson recommends screening beginning at age 40.
“Under the revised Task Force guidelines, up to half of Mexican-origin women with breast cancer may be undiagnosed or diagnosed in late stages,” says Patricia Miranda, Ph.D., a Kellogg Health Scholar post-doctoral fellow in the Center for Research on Minority Health in the Department of Health Disparities Research at MD Anderson and the study’s lead author.
The research was supported in part by the Kellogg Health Scholars Program, the National Cancer Institute, the Caroline W. Law Fund for Cancer Prevention and Risk Assessment, the National Center on Minority Health and Health Disparities, and funds collected in the Comprehensive Tobacco Settlement of 1998 and appropriated by the 76th legislature to MD Anderson.
SUMO Works With Replication Protein A Complex to Repair DNA
Investigators led by an MD Anderson physician-scientist have shown for the first time that the protein SUMO can team up with RPA70, a component of the replication protein A (RPA) complex, to facilitate DNA repair.
The chemotherapy drug camptothecin and ionizing radiation both attack cancer cells by causing double-strand DNA breaks. Cells respond by activating homologous recombination to repair the damage. The newly discovered connection offers a potential target for short-circuiting repair.
“If a mutant protein that cannot be modified by SUMO is substituted for RPA70, the cells are much more sensitive to chemotherapy and ionized radiation,” says corresponding author Edward T.H. Yeh, M.D., professor and chair of MD Anderson’s Department of Cardiology.
Funding for this research was provided by the National Institutes of Health.
Study Ties Abnormal Cells in Blood to Lung Cancer
A research team led by MD Anderson scientists has discovered a novel way to detect genetically abnormal cells in the blood of non-small cell lung cancer patients that match abnormalities found in tumor cells and increase in number with severity of the disease.
Investigators have conducted what they believe to be the first study to use a technique called fluorescence in situ hybridization (FISH) to detect abnormal circulating cells that have aberrations found in non-small cell lung cancer.
FISH detects and quantifies abnormal cells by using dye-labeled DNA probes of cell chromosomes that cause cells with the targeted genetic abnormalities to light up.
“We suspect additional research will show that these circulating abnormal cells are circulating non-small cell lung cancer cells,” says study corresponding author Ruth Katz, M.D., professor in MD Anderson’s Department of Pathology. “Blood tests for these circulating tumor cells could be used to diagnose lung cancer earlier, monitor response to therapy and detect residual disease in patients after treatment.”
This research was funded by grants and a fellowship from the National Cancer Institute (NCI), by MD Anderson’s NCI Lung Cancer SPORE (Specialized Programs of Research Excellence) grant and by a grant from AstraZeneca.