October 23, 2012
By David Martin
|Sushanta Banerjee, Ph.D., (left) and Snigdha Banerjee, Ph.D.|
A compound found in green tea may lead to better treatment of breast and pancreatic cancers, according to research by two University of Kansas Medical Center faculty members.
Sushanta K. Banerjee, Ph.D., and Snigdha Banerjee, Ph.D., discovered a gene that acts as a marker for non-invasive breast cancer tumors. Their study determined that when the gene is activated, breast cancer cells – and possibly pancreatic cancer cells – are prevented or delayed from spreading to other parts of the body.
It turns that a compound found in green tea seems to activate this particular gene. Sushanta Banerjee says he is "optimistic that this chemical may eventually help in preventing the progression of the disease from a non-aggressive to aggressive cancer."
Genes in the CCN family play a role in everything from pregnancy to wound healing. The Banerjees, who are married, have studied one particular member of the family, CCN5, for several years. Their most recent paper, published in the Journal of Cell Communication and Signaling, describes CCN5 as a "micromanager" of breast cancer.
CCN5, the authors believe, tells breast cancer cells how to behave. Specifically, the gene appears regulates the cells' ability to gain "stemness," or become more aggressive.
To conduct the research, the Banerjees studied tissue samples from The University of Kansas Hospital and other sources. They looked at two types of breast cancer cells – those that had invaded other parts of the body and those that had not.
The microscope revealed a difference in the cells. CCN5 proteins were present in the cancer cells that remained localized. But in the cancer cells that had invaded other organs, the proteins were absent.
The results suggest that activating the CCN5 gene – alone or in combination with current therapies – could provide a new strategy for oncologists and their breast cancer patients. "Our hypothesis is that if we keep the CCN5 gene ‘on' in human patients, the disease will not progress," Shusanta Banerjee says.
The finding may be relevant for the treatment of pancreatic cancer, as well. According to the authors, it is likely that CCN5 also plays a preventive role in the progression of pancreatic cancer. What's the connection with breast cancer? Duct cells. Breasts have milk ducts. The pancreas secretes digestive juices through a duct.
A proper method for reactivating the CCN5 gene in aggressive breast cancer or pancreatic cancer cells has not been established. At present, no such therapeutic options exist. However, the KU study suggests that the major catechin in found in green tea – epigallocatechin gallate, or ECGC – can turn on the gene in breast cancer cells in lab tissue. What's unknown is the proper amount. "We don't know how much EGCG you need in a patient to keep it on," Sushanta Banerjee says.
Green tea is not the first substance from the natural world that Banerjee has studied. In 2006, his group published a study describing the anticancer properties of crocetin, a compound found in saffron.
Research at the VA
The Banerjees work in a lab at the Veterans Affairs Medical Center in Kansas City, Mo. Sushanta Banerjee, a professor of medicine in the division of hematology and oncology, is the research director of the cancer research unit at the Kansas City VA. (Banerjee holds a secondary faculty appointment as an associate professor of anatomy and cell biology.) Snigdha Banerjee, a research associate professor of medicine in the division of hematology and oncology, is also a VA-funded investigator.
While patient care may be the most obvious function of the VA's medical program, research is also a priority. The VA will spend $580 million this year to encourage the pursuit of new knowledge and the application of these discoveries to veterans' health care.
The VA supports many researchers who, like the Banerjees, work to better understand the molecular basis of breast cancer and other diseases. Joel Kupersmith, M.D., the VA's chief research and development officer, has called genomics "the direction for research in the 21st century."
One in eight women will develop breast cancer in her lifetime. Given that women are now the fastest growing subgroup of U.S. veterans, the breast cancer research in the Banerjee lab seems right at home at a VA medical center.
Early detection and other factors have reduced the death rate from breast cancer. But as the Banerjees note on their most recent study, the options for treating advanced stages of breast cancer are still fairly limited. More knowledge of the disease's molecular origins and its progression should lead to better therapies – and longer living veterans.