Inflammation Is Key to Breast Cancer Growth
What makes breast cancer develop and grow? Inflammation, say investigators at Kimmel Cancer Center at Thomas Jefferson University. Although inflammation has long been suspected as a culprit in the growth of breast cancer, scientists say this new study proves it.
Selectively stopping inflammation can stop breast cancer
After more than a decade of highly focused research, scientists have proven that an inflammatory process within breast tissue promotes the growth of cancer stem cells that result in tumors. Perhaps even more important is they have shown that when they selectively inactivate the inflammation, they can stop breast cancer from developing.
Scientists have long believed that NFKB (nuclear factor kappa-light-chain-enhancer of activated B cells), which turns on the inflammatory process, is key to the development of breast cancer, but they could not prove it definitively because the mouse models available died when they tried to test their theory.
The development of a new mouse model that allows researchers to regulate the inflammatory system within the adult animal’s normal breast tissue made the necessary research possible. Specifically, the researchers found that when they selectively blocked inflammation just in the breast tissue of the new mouse model, tumors did not develop and the number of cancer stem cells also declined.
According to Richard G. Pestell, MD, PhD, director, Kimmel Cancer Center and Chairman of Cancer Biology, “these studies show for the first time that inactivating the NFKB inflammatory pathway in the breast epithelium blocks the onset and progression of breast cancer in living animals.”
“This finding has clinical implications,” says co-author Michael Lisanti, Leader of the Program in Molecular Biology and Genetics of Cancer at Jefferson. That is good news for women. According to the American Cancer Society, about 1 in 8 women in the United States will develop invasive breast cancer over their lifetime.
In 2010, the Society estimates than 207,090 new cases of invasive breast cancer will be diagnosed in the United States, along with 54,010 new cases of non-invasive breast cancer. Men are included as well, with nearly 2,000 new cases expected to be diagnosed in 2010.
Although the good news is that breast cancer incidence rates in the United States declined by about 2 percent per year from 1999 to 2006, nearly 40,000 women in the United States are expected to die of the disease in 2010. About 28 percent of cancers in women are breast cancer.
The finding that inflammation is the key to breast cancer growth is a significant breakthrough. Lisanti notes that while suppressing the inflammatory process in the whole body can cause side effects, “these studies provide the rationale for more selective anti-inflammatory therapy directed just to the breast.”
American Cancer Society
Liu M et al. Cancer Research 2010 Dec 15; 70:10464