Finding ways to kill cancer stem cells has been one of the holy grails in cancer research. While this is a target of biotechnology companies working on cancer treatment, scientists have already discovered dietary factors (cancer stem cell-killing foods) that have the ability to kill cancer stem cells, at least in some forms of cancer.
Cancer stem cells are responsible for initiating many cancers, as well as igniting the recurrence of cancers after treatment. Here are the top cancer stem cell-killing foods…
Green Tea and Matcha Tea
Green tea has many useful functions, including the ability to kill cancer stem cells. Scientists at Nanjing Medical University and Sun Yat-Sen University Cancer Center in China studied the effect of the green tea polyphenol, epigallocatechin-3-gallate (EGCG), in the lab and found that it could reduce the growth of colon cancer stem cells by 50 percent.
In addition, EGCG forced the cancer stem cells to commit cell suicide through the process of apoptosis. Another study from the University of Salford in England showed that matcha green tea, a form of powderized tea leaf, can interrupt the metabolic pathway of breast cancer stem cells, depriving them of energy and causing them to die. The effect of the EGCG in green tea on targeting cancer stem cells may help explain the protective effects of tea against colon and other cancers.
Originating from Peru, purple potatoes were prized by the ancient Inca for their nutritive benefits. They contain the bioactive anthocyanin, a blue-purple pigment that also gives many dark berries their hue. Scientists at Penn State University explored the effect of purple potatoes on cancer stem cells. In the lab, they fed mice that are at high risk for developing colon cancer the dietary equivalent of one purple potato (Purple Majesty variety) each day for a week.
They compared the effects of the potato with that of an anti-inflammatory drug called Sulindac, which is known to suppress colon polyps and colon cancer development. After one week, the colons of the mice were examined. The mice fed purple potatoes had 50 percent fewer tumors. When the colon tissues were more closely examined under the microscope, there was a 40 percent increase in the killing of colon cancer stem cells compared to the group that did not eat purple potatoes. They found that the cancer stem cells in mice fed purple potatoes were deprived of key survival factors.
When the scientists removed the cancer stem cells from the mice and exposed them to a purple potato extract, they found the extract caused a twenty-two-fold reduction of aggressiveness in the behavior of the cancer stem cells.
The scientists prepared the purple potato in different ways, including baking, dicing, and freeze-drying, yet the bioactive cancer stem cell-fighting components appear to be stable even under different conditions and preparation techniques. Given their effects, purple potatoes may have in addition to their marvelous color features unique cancer-fighting properties that traditional white potatoes do not.
Walnuts are popular tree nuts that are eaten raw, roasted, candied, or even pickled. They are nutrient dense and contain bioactives like gallic acid, chlorogenic acid, and ellagic acid. As described earlier, eating walnuts is associated with a reduced risk for developing colon cancer and also improves survival in patients who have colon cancer. Scientists from Ewha Womans University, Seoul National University, and Sungkyunkan University in South Korea studied a walnut extract for its ability to kill cancer stem cells.
In the lab, they grew colon cancer stem cells isolated from a patient, and exposed the cells to a walnut extract. After two days of exposure, the number of cancer stem cells treated with walnut extract declined by 34 percent. By six days, there was a stunning 86 percent suppression of cancer stem cell growth. The potent effect of walnuts on cancer stem cells might help explain the results of the study of 826 patients with stage 3 colon cancer who had a 57 percent lower chance of death, and a 42 percent lower chance of cancer recurrence associated with eating nuts. If you have colon cancer, eating walnuts may literally save your life.