(NaturalNews) Natural chemicals found in the spices turmeric and black pepper appear to stop the growth of breast tumors, according to a study conducted by researchers from the University of Michigan Comprehensive Cancer Center and published in the journal Breast Cancer Research and Treatment.
Researchers applied a solution containing both curcumin, found in turmeric, and piperine, which makes black pepper spicy, to breast cancer cells in a laboratory, using concentrations 20 times higher than those found in the human diet. They found that the solution hampered the ability of stem cells to propagate but did not affect the differentiation of normal breast cells.
"This shows that these compounds are not toxic to normal breast tissue," lead author Madhuri Kakarala said.
Cancer stem cells are the cells in tumors that allow it to keep growing without limit. Current chemotherapy treatments are unable to affect stem cells, which is part of the reason that cancers can spread and recur even in those undergoing treatment.
"If we can limit the number of stem cells, we can limit the number of cells with potential to form tumors," Kakarala said.
The researchers found that the piperine appeared to make the curcumin more effective. They also found that the solution affected cancer stem cells regardless of whether the tumors were estrogen-sensitive or not. This is an especially significant finding because the cancer-preventive drugs tamoxifen or raloxifene, which can have highly toxic side effects, do not affect estrogen-independent tumors.
"The concept that dietary compounds can help is attractive, and curcumin and piperine appear to have very low toxicity," Karkala said.
Previous studies have linked a diet high in turmeric to a lower risk of breast, colon, prostate and lung cancers. Black pepper and piperine have both also been shown to suppress the development of colon and lung tumors in animal tests.
Sources for this story include: health.usnews.com; timesofindia.indiatimes.com.