Breast Cancer: Prevention is better than Cure – Dr Jayanti Thumsi, Oncologist, Crest Foundation- Bangalore
WASHINGTON: It seems like, there’s more to soy than meets the eye as a new research has suggested that it may have the ability to suppress breast cancer tumour growth.
A University of Arizona Cancer Center research team is engaged in a series of studies to investigate how genistein, a component of soy foods, might suppress the development of breast cancer.
The team’s most recent study suggested that genistein can protect BRCA1, a gene that plays a pivotal role in thwarting tumor development in breast tissue. The team is led by Donato F. Romagnolo and Ornella I. Selmin.
A normally functioning breast cell has estrogen receptors, into which the body’s natural estrogens fit like a key into a lock, regulating cell growth. Doctors can exploit these receptors by using drugs that attach to them, delivering chemotherapy to cancerous cells with drugs like tamoxifen. In many breast tumors, however, this receptor is missing, rendering tamoxifen ineffective
One receptor, the aromatic hydrocarbon receptor (AhR), activated by environmental carcinogens like dioxins, tobacco smoke, products of UV light exposure and some fatty acid metabolites, is of particular interest to the UA Cancer Center team. AhR silences BRCA1, triggering a cascade of undesirable effects. When BRCA1 is unable to carry out its duties as a tumor suppressor, cancerous cells can proliferate.
“Lifetime intake of soy in Asian women has been linked to reduced risk of breast cancer,” said Romagnolo. Genistein is the predominant isoflavone found in soy and it may actually block DNA methylation, the silencing of the BRCA1 gene.
The experiments used cells from human breast tumors, including one cell line that originally was derived from a UA Cancer Center patient. With successful cell experiments behind them, the team is immersed in studies using mice specialized for breast cancer research. If their next wave of experiments supports their hypothesis, the team could move on to clinical studies in humans