American Institute for Cancer Research
Newsletter 88, Summer 2005
Research suggests that diet can affect a man's risk of prostate cancer. Mounting evidence indicates that certain foods may aid in preventing this cancer if they are part of a mostly plant-based diet.
Overall, scientists believe that cancer risk can be lowered 30-40 percent by eating a diet that contains mainly plant-based foods, like vegetables, fruits, whole grains and beans, along with getting regular exercise and maintaining a healthy weight. Studies show these healthy habits can also help prevent prostate cancer.
Now researchers are beginning to get a clearer picture of how particular foods may lower prostate cancer risk. Among them are tomatoes and cruciferous vegetables, such as broccoli. Other foods that may fight prostate cancer include soy, garlic, green tea and flaxseed. Minerals such as zinc and selenium, as well as vitamin E, are also under investigation.
A Menu for Prevention
Cruciferous vegetables: With funding from AICR, researchers are investigating how the compound indole-3-carbinol (I3C) may inhibit the growth of prostate cancer cells in cultures and help to eliminate tumor cells in the body. A new study will compare the effects of consuming cruciferous vegetables to taking I3C supplements on lowering PSA (prostate-specific antigen) levels in patients that have had prostate surgery. Researchers are also looking at whether isothiocyanates, found in cruciferous vegetables, can help prevent prostate cancer.
Scientists also have found evidence that eating cancer-fighting foods together, like tomatoes with broccoli, may maximize the cancer-preventive effect of these foods.
Selenium: Selenium is found in fish, poultry,eggs, grains, mushrooms and other foods. With a grant from AICR, Arthur Sytkowski, M.D., of Beth Israel Deaconess Medical Center in Boston, has been investigating how selenium may suppress prostate cancer.
"In laboratory and animal studies on prostate cancer cells, when the gene for this protein (which scientists call hSP56) was turned on, prostate cancer slowed. But when the gene was turned off, the cancer grew and spread more rapidly," says Dr. Sytkowski. Selenium binds to the protein and appears to regulate its action, which may help explain selenium's role in cancer prevention.
To find out whether selenium and vitamin E supplements can lower prostate cancer risk, more than 35,000 men have enrolled in the Selenium and Vitamin E Cancer Prevention Trial. Results are expected in 2013.
Soy: Laboratory and animal studies show that genistein, a phytochemical in soybeans, may inhibit prostate cancer cell growth and tumor development. In an AICR-supported study of early stage prostate cancer patients, Nagi Kumar, Ph.D., of the University of South Florida, found that PSA levels in the blood and other indicators of prostate cancer risk were moderately reduced in patients taking an isoflavone-rich supplement compared to those not taking the supplement. (The PSA test is controversial; however it may be a valuable screening when repeated with the same patient.)
"Although long-term trials are needed, it is reasonable for men concerned about their prostate health to incorporate soy foods into their diets 2-3 times per week," says Dr. Kumar.
With funding from AICR, Gilda Hillman, Ph.D., of the Karmanos Cancer Institute at Wayne State University in Michigan, has been studying how soy may potentially increase the effect of radiation therapy for prostate cancer.
"In cell cultures, genistein increased the destruction of prostate tumor cells when given with radiation," says Dr. Hillman. "We also found that prolonged feeding of genistein to mice, combined with tumor irradiation, caused a significant reduction of cancer growth in the prostate and controlled the spread of cancer to the lymph nodes."
On the horizon: Garlic, green tea, flaxseed and zinc are also being investigated through AICR-sponsored research. For example, in laboratory and animal studies, epigalocatechin-3-gallate (EGCG), a polyphenol in green tea, stopped the development and growth of prostate cancer cells. A new clinical study of prostate cancer patients will examine to what degree drinking green tea can lower PSA levels and kill cancer cells. The effects of a flaxseed-supplemented diet on prostate cell growth and PSA levels are also being studied. Flaxseed is rich in lignans, a type of fiber, and in omega-3 fatty acids, which may slow tumor growth.
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Newsletter 88, Summer 2005
Plant Foods May Protect Against Prostate Cancer
Overall, scientists believe that cancer risk can be lowered 30-40 percent by eating a diet that contains mainly plant-based foods, like vegetables, fruits, whole grains and beans, along with getting regular exercise and maintaining a healthy weight. Studies show these healthy habits can also help prevent prostate cancer.
Now researchers are beginning to get a clearer picture of how particular foods may lower prostate cancer risk. Among them are tomatoes and cruciferous vegetables, such as broccoli. Other foods that may fight prostate cancer include soy, garlic, green tea and flaxseed. Minerals such as zinc and selenium, as well as vitamin E, are also under investigation.
A Menu for Prevention
Cruciferous vegetables: With funding from AICR, researchers are investigating how the compound indole-3-carbinol (I3C) may inhibit the growth of prostate cancer cells in cultures and help to eliminate tumor cells in the body. A new study will compare the effects of consuming cruciferous vegetables to taking I3C supplements on lowering PSA (prostate-specific antigen) levels in patients that have had prostate surgery. Researchers are also looking at whether isothiocyanates, found in cruciferous vegetables, can help prevent prostate cancer.
Scientists also have found evidence that eating cancer-fighting foods together, like tomatoes with broccoli, may maximize the cancer-preventive effect of these foods.
Selenium: Selenium is found in fish, poultry,eggs, grains, mushrooms and other foods. With a grant from AICR, Arthur Sytkowski, M.D., of Beth Israel Deaconess Medical Center in Boston, has been investigating how selenium may suppress prostate cancer.
"In laboratory and animal studies on prostate cancer cells, when the gene for this protein (which scientists call hSP56) was turned on, prostate cancer slowed. But when the gene was turned off, the cancer grew and spread more rapidly," says Dr. Sytkowski. Selenium binds to the protein and appears to regulate its action, which may help explain selenium's role in cancer prevention.
To find out whether selenium and vitamin E supplements can lower prostate cancer risk, more than 35,000 men have enrolled in the Selenium and Vitamin E Cancer Prevention Trial. Results are expected in 2013.
Soy: Laboratory and animal studies show that genistein, a phytochemical in soybeans, may inhibit prostate cancer cell growth and tumor development. In an AICR-supported study of early stage prostate cancer patients, Nagi Kumar, Ph.D., of the University of South Florida, found that PSA levels in the blood and other indicators of prostate cancer risk were moderately reduced in patients taking an isoflavone-rich supplement compared to those not taking the supplement. (The PSA test is controversial; however it may be a valuable screening when repeated with the same patient.)
"Although long-term trials are needed, it is reasonable for men concerned about their prostate health to incorporate soy foods into their diets 2-3 times per week," says Dr. Kumar.
With funding from AICR, Gilda Hillman, Ph.D., of the Karmanos Cancer Institute at Wayne State University in Michigan, has been studying how soy may potentially increase the effect of radiation therapy for prostate cancer.
"In cell cultures, genistein increased the destruction of prostate tumor cells when given with radiation," says Dr. Hillman. "We also found that prolonged feeding of genistein to mice, combined with tumor irradiation, caused a significant reduction of cancer growth in the prostate and controlled the spread of cancer to the lymph nodes."
On the horizon: Garlic, green tea, flaxseed and zinc are also being investigated through AICR-sponsored research. For example, in laboratory and animal studies, epigalocatechin-3-gallate (EGCG), a polyphenol in green tea, stopped the development and growth of prostate cancer cells. A new clinical study of prostate cancer patients will examine to what degree drinking green tea can lower PSA levels and kill cancer cells. The effects of a flaxseed-supplemented diet on prostate cell growth and PSA levels are also being studied. Flaxseed is rich in lignans, a type of fiber, and in omega-3 fatty acids, which may slow tumor growth.
All active news articles