A signalling pathway that influences how sensitive cancer cells are to the beneficial effects of dietary restriction is described in this week's Nature.
Dietary restriction - eating less calories while maintaining essential vitamins and minerals - can extend lifespan, and reduce cancer incidence and growth. But some types of cancer cell are more sensitive to the anti-growth effects of dietary restriction than others, Nada Kalaany and David Sabatini report. The effect hinges on the activity of the phosphatidylinositol-3-kinase (PI3K) pathway. If the pathway is active, dietary restriction has no effect on cancer cells. However, if the pathway is inactive, tumours are sensitive to dietary restriction.
Dietary vitamin D and cancers of the oral cavity and esophagus.
Lipworth L, Rossi M, McLaughlin JK, Negri E, Talamini R, Levi F, Franceschi S, La Vecchia C.
Ann Oncol. 2009 Sep;20(9):1576-81. Epub 2009 Jun 1.
PMID: 19487490
Conclusion: We observed inverse associations between dietary vitamin D intake and risk of SCCE and, perhaps, oral/pharyngeal cancer, which were most pronounced among heavy current smokers and heavy consumers of alcohol.
ScienceDaily (Feb. 25, 2009) - Researchers at Purdue University have precisely measured the impact of a high-fat diet on the spread of cancer, finding that excessive dietary fat caused a 300 percent increase in metastasizing tumor cells in laboratory animals.
Tumours with PI3K activation are resistant to dietary restriction.
Nada Y. Kalaany & David M. Sabatini
Nature. Published online 11 March 2009
doi:10.1038/nature07782
Dietary omega-3 polyunsaturated fatty acids plus vitamin E restore immunodeficiency and prolong survival for severely ill patients with generalized malignancy: a randomized control trial.
Gogos CA, Ginopoulos P, Salsa B, Apostolidou E, Zoumbos NC, Kalfarentzos F.
Cancer. 1998 Jan 15;82(2):395-402.
PMID: 9445198
The effect of dietary omega-3 polyunsaturated fatty acids on T-lymphocyte subsets of patients with solid tumors.
Gogos CA, Ginopoulos P, Zoumbos NC, Apostolidou E, Kalfarentzos F.
Cancer Detect Prev. 1995;19(5):415-7.
PMID: 7585727
Vitamin D from dietary intake and sunlight exposure and the risk of hormone-receptor-defined breast cancer.
Blackmore KM, Lesosky M, Barnett H, Raboud JM, Vieth R, Knight JA.
Am J Epidemiol. 2008 Oct 15;168(8):915-24. Epub 2008 Aug 27.
PMID: 18756015
doi:10.1093/aje/kwn198
This study suggests that vitamin D is associated with a reduced risk of breast cancer regardless of ER/PR status of the tumor. Future studies with a larger number of receptor-negative and mixed tumors are required.
Dietary intake of vitamin K and risk of prostate cancer in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg).\nNimptsch K, Rohrmann S, Linseisen J.\nAm J Clin Nutr. 2008 Apr;87(4):985-92.\nPMID: 18400723
LYSAKER, Norway, April 11, 2008-An increased intake of vitamin K2 may reduce the risk of prostate cancer by 35 per cent, suggest results from the European Prospective Investigation into Cancer and Nutrition (EPIC). The findings, based on dietary intake from 11,319 men taking part in the EPIC Heidelberg cohort, are published in this month's issue of the American Journal of Clinical Nutrition.
"HOUSTON - A diet that incorporates a daily dose of pistachios may help reduce the risk of lung and other cancers, according to data presented at the American Association for Cancer Research Frontiers in Cancer Prevention Research Conference, held Dec. 6-9.
"It is known that vitamin E provides a degree of protection against certain forms of cancer. Higher intakes of gamma-tocopherol, which is a form of vitamin E, may reduce the risk of lung cancer," said Ladia M. Hernandez, M.S., R.D., L.D., senior research dietitian in the Department of Epidemiology at the University of Texas M. D. Anderson Cancer Center, and doctoral candidate at Texas Woman's University - Houston Center.
"Pistachios are a good source of gamma-tocopherol. Eating them increases intake of gamma-tocopherol so pistachios may help to decrease lung cancer risk," she said.
Pistachios are known to provide a heart-healthy benefit by producing a cholesterol-lowering effect and providing the antioxidants that are typically found in food products of plant origin. Hernandez and colleagues conducted a six-week, controlled clinical trial to evaluate if the consumption of pistachios would increase dietary intake and serum levels of gamma-tocopherol. A pistachio-rich diet could potentially help reduce the risk of other cancers from developing as well, according to Hernandez.
"Because epidemiologic studies suggest gamma-tocopherol is protective against prostate cancer, pistachio intake may help," she said. "Other food sources that are a rich source of gamma-tocopherol include nuts such as peanuts, pecans, walnuts, soybean and corn oils.""
Benefits of Vitamin D Supplementation
Joel M. Kauffman, Ph.D.
Journal of American Physicians and Surgeons
Volume 14 Number 2 - Summer 2009
Clinical trials show that vitamin D supplementation at higher
levels than previously recommended is beneficial for many
conditions. It decreases the frequency of falls and fractures, helps
prevent cardiovascular disease, and reduces symptoms of colds or
influenza. Benefits are also seen in diabetes mellitus, multiple
sclerosis, Crohn disease, pain, depression, and possibly autism.
Sunlight does not cause an overdose of vitamin D production,
and toxicity from supplementation is rare. Dose recommendations
are increasing, but appear to be lagging the favorable trial results. A
number of common drugs deplete vitamin D levels, and others may
limit its biosynthesis from sunlight.
People with adequate levels from sun exposure will not benefit
from supplementation. While dietary intake is helpful,
supplementation is better able to raise serum 25-hydroxyvitamin D ,
the major circulating metabolite, to the level now thought adequate,
30-50 ng/mL.
Where there is inadequate daily sun exposure, oral doses of
1,000-2,000 IU/d are now considered routine, with much higher
doses (up to 50,000 IU) for rapid repletion now considered safe.
Coriolus versicolor is a mushroom of the Basidiomycetes class. It was used initially in Traditional Chinese medicine as a tonic, but recent studies suggest that it has immunostimulant and anti-tumor properties. Polysaccharide-K (PSK), a proprietary product derived from Coriolus, was developed for cancer treatment in Japan. When used as an adjuvant, PSK appears to improve survival rates in patients with gastric (1) (2) and colorectal (3) (4) (5) cancers. Other Coriolus extracts, such as polysaccharide-peptide (PSP) and VPS, are available as dietary supplements. When used in conjunction with chemotherapy, PSP may benefit patients with advanced non-small cell lung cancer (7). Other clinical studies using Coriolus extract alone or in combination with other botanicals also suggest positive immunomodulatory effects (8) (9). However, studies on breast cancer (10), hepatocellular carcinoma (11), and leukemia (12) produced mixed results. A hot water extract of Coriolus, VPS, was found to enhance development of large intestinal tumors in mice (21). Coriolus extracts are generally well tolerated but minor adverse effects have been reported.
Many over-the-counter Coriolus products are not standardized, making it difficult to compare potency between brands. It is also unclear if PSK, PSP and other Coriolus extracts have comparable effects.
High prevalence of vitamin D deficiency despite supplementation in premenopausal women with breast cancer undergoing adjuvant chemotherapy.
Crew KD, Shane E, Cremers S, McMahon DJ, Irani D, Hershman DL.
J Clin Oncol. 2009 May 1;27(13):2151-6. Epub 2009 Apr 6.
PMID: 19349547
DOI: 10.1200/JCO.2008.19.6162
Conclusion Vitamin D deficiency is highly prevalent in women with breast cancer. The current recommended dietary allowance of vitamin D is too low to increase serum 25-OHD greater than 30 ng/mL. Optimal dosing for bone health and, possibly, improved survival has yet to be determined.
What is VITAL?
The VITamin D and OmegA-3 TriaL (VITAL) is a research study in 20,000 U.S. men and women investigating whether taking daily dietary supplements of vitamin D (about 2000 IU) or fish oil (about 1 gram of omega-3 fatty acids) reduces the risk of developing cancer, heart disease, and stroke in people who do not have a prior history of these illnesses. Recruitment for the study will begin in January 2010.
Derived from the cap and stem of the mushroom. The active constituent is thought to be a beta-glucan polysaccharide. The whole mushroom is used primarily as a dietary element, but extracts and supplements are sold as immune stimulants for patients with HIV or cancer. While no adverse effects have been reported, some studies reveal a hypoglycemic effect following administration of maitake extract (9) (12). Maitake was shown to enhance bone marrow colony formation, reduce doxorubicin toxicity in vitro (11), and to inhibit tumor metastasis
ScienceDaily (Mar. 24, 2009) - Individuals who took a dietary supplement called "factor D", which included selenium, vitamin E, and beta-carotene, continued to have lower gastric cancer and overall mortality 10 years after supplementation ceased compared with individuals who did not take the supplements, according to long-term follow-up data from the randomized, double-blind General Population Nutrition Intervention Trial in Linxian, China.