Serum 25-hydroxyvitamin D and colon cancer: eight-year prospective study.
Garland CF, Comstock GW, Garland FC, Helsing KJ, Shaw EK, Gorham ED.
Lancet. 1989 Nov 18;2(8673):1176-8.
PMID: 2572900
Blood samples taken in 1974 in Washington County, Maryland, from 25 620 volunteers were used to investigate the relation of serum 25-hydroxyvitamin D (25-OHD) with subsequent risk of getting colon cancer. 34 cases of colon cancer diagnosed between August, 1975, and January, 1983, were matched to 67 controls by age, race, sex, and month blood was taken. Risk of colon cancer was reduced by 75% in the third quintile (27-32 ng/ml) and by 80% in the fourth quintile (33-41 ng/ml) of serum 25-OHD. Risk of getting colon cancer decreased three-fold in people with a serum 25-OHD concentration of 20 ng/ml or more. The results are consistent with a protective effect of serum 25-OHD on colon cancer.
The role of vitamin D in cancer prevention.
Garland CF, Garland FC, Gorham ED, Lipkin M, Newmark H, Mohr SB, Holick MF.
Am J Public Health. 2006 Feb;96(2):252-61. Epub 2005 Dec 27. Review.
PMID: 16380576
DOI: 10.2105/AJPH.2004.045260
Vitamin D status differs by latitude and race, with residents of the northeastern United States and individuals with more skin pigmentation being at increased risk of deficiency. A PubMed database search yielded 63 observational studies of vitamin D status in relation to cancer risk, including 30 of colon, 13 of breast, 26 of prostate, and 7 of ovarian cancer, and several that assessed the association of vitamin D receptor genotype with cancer risk.
The majority of studies found a protective relationship between sufficient vitamin D status and lower risk of cancer. The evidence suggests that efforts to improve vitamin D status, for example by vitamin D supplementation, could reduce cancer incidence and mortality at low cost, with few or no adverse effects
"A study conducted by Cedric Garland and other prominent vitamin D researchers determined that women with vitamin D levels above 52 ng/ml have half the risk of developing breast cancer as those with 13 ng/ml! Garland (et al) estimates that 58,000 new cases of breast cancer in the U.S. could be prevented per year by raising vitamin D levels to 52 ng/ml. Imagine what the global impact could be! "
Relationship between low ultraviolet B irradiance and higher breast cancer risk in 107 countries.
Mohr SB, Garland CF, Gorham ED, Grant WB, Garland FC.
Breast J. 2008 May-Jun;14(3):255-60. Epub 2008 Apr 17.
PMID: 18422861
DOI: 10.1111/j.1524-4741.2008.00571.x
There was a protective effect of UVB irradiance on risk of breast cancer that was independent of fertility rate, proportion of the population overweight, alcohol intake, animal energy intake, and other covariates.
Induction of ovarian cancer cell apoptosis by 1,25-dihydroxyvitamin D3 through the down-regulation of telomerase.
Jiang F, Bao J, Li P, Nicosia SV, Bai W.
J Biol Chem. 2004 Dec 17;279(51):53213-21. Epub 2004 Oct 12.
PMID: 15485861
doi: 10.1074/jbc.M410395200
Overall, the study suggests that the down-regulation of telomerase activity by 1,25(OH)2VD3 and the resulting cell death are important components of the response of OCa cells to 1,25(OH)2VD3-induced growth suppression.
Progressive shortening of telomere associated with cell divisions limits the life span of normal cells and eventually leads to senescence. To become immortal, human cancers including OCa are invariably associated with activation of mechanism that maintains telomere length. Approximately 85-90% of cancers show reactivation of telomerase. The present study shows that telomerase in OCa cells is down-regulated by 1,25(OH)2VD3. Down-regulation of telomerase is due to decreased stability of hTERT mRNA rather than VDRE-mediated transcriptional repression through the putative VDRE present in the regulatory region of the hTERT gene.
It is known that the inhibition of telomerase may lead to a phenotypic lag during which cells would continue to divide until the point at which the telomeres became critically short. This phenomenon may explain why the apoptotic induction by 1,25(OH)2VD3 needs the treatment for more than 6 days. As mentioned in the results, no detectable shortening of telomeric repeats was observed in parental OVCAR3 cells after 9 days of treatment with 1,25(OH)2VD3 (Fig. 4D). This is likely due to the fact that the short telomere (about 3 kb) in OVCAR3 cells is very close to the minimal length required for survival and that cells with detectably shorter telomere may have been selected against apoptosis. It has been shown that transformed human cells enter crisis once the terminal restriction fragment of the telomere reaches a length of about 4 kb. This is insufficient to protect chro
Tuohimaa P, Pukkala E, Scelo G, Olsen JH, Brewster DH, Hemminki K, Tracey E, Weiderpass E, Kliewer EV, Pompe-Kirn V, McBride ML, Martos C, Chia KS, Tonita JM, Jonasson JG, Boffetta P, Brennan P.
Does solar exposure, as indicated by the non-melanoma skin