By Julie Mitchell
Results from the most comprehensive study of breast cancer to date show that one of the most lethal subtypes of the disease share many genetic traits with a high-grade serious ovarian cancer that is extremely difficult to treat. The findings suggest that the two cancers have similar genetic roots that may lead to new treatment plans for both.
The study, funded by theU.S. National Institutes of Health (NIH) , is called theCancer Genome Atlas and also revealed more information on the molecular structure of the four main types of breast cancer. The study was published online on September 23rd and will appear in October 4 print edition of the journal, Nature .
A collaborative effort between the National Cancer Institute (NCI) and theNational Human Genome Research Institute (NHGRI) , the research showed that basal-like breast tumors and some ovarian tumors might both be susceptible to agents that inhibit blood vessel growth and might be treated by cutting off blood supply to the tumor and medications that inhibit DNA repair. The basal-like subgroup of cancers has been called the Triple Negative Threat Breast Cancer because many of these types of tumors are negative when tested for three common receptors. The frequencies of genetic mutations were very much the same in both basal-like subtype breast cancer and serious ovarian cancer.
A national consortium of researchers analyzed tumors from 825 women with breast
cancer and used six different technologies to analyze nearly 350 tumors. The study confirmed that there are four key subtypes of breast cancer: HER2-enriched (HER2E), luminal A, luminal B, and basal-like. According to theWorld Health Organization , breast cancer is the most common cancer in women worldwide, comprising 16% of all female cancers. The majority of cases are sporadic, meaning that there is no family history of breast cancer.
In a news release from the National Human Genome Research Institute, part of the NIH, Harold Varmus, MD and NCI director, said, “The molecular similarity of one of the principal subtypes of breast cancer to that found in ovarian cancer gives us additional leverage to compare treatments and outcomes across those two cancers. This treasure trove of genetic information will need to be examined in great detail to identify how we can used it functionally and clinically.”
The study’s authors, Matthew J. Ellis, MD, PhD, the Anheuser-Busch Chair in Medical Oncology at Washington University School of Medicine in St. Louis, and Charles M. Perou, PhD, at the University of North Carolina , hope that the discovery of how cancer genome’s mutations are essential for cancer progression will be a critical step toward improving breast cancer therapies.
