5X less risk of Kidney cancer if good ratio of Vitamin D binding protein to circulating vitamin D – Nov 2013

Vitamin D binding protein, circulating vitamin D, and risk of renal cell carcinoma

International Journal of Cancer, DOI: 10.1002/ijc.28596
Alison M. Mondul 1, mondulam@mail.nih.gov
Stephanie J. Weinstein 1,
Kristin A. Moy 1,
Satu Männistö 2,
Demetrius Albanes 1
1 Nutritional Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Rockville, MD
2 Department of Chronic Disease Prevention, National Institute for Health and Welfare, Helsinki, Finland

Cell culture experiments suggest that vitamin D may inhibit renal carcinogenesis, but human studies of circulating 25-hydroxyvitamin D (25(OH)D), the accepted measure of vitamin D status, and kidney cancer have been null. Limited research has examined the role of circulating vitamin D binding protein (DBP) in the association between 25(OH)D and disease risk, and it is unclear whether free 25(OH)D in circulation is a better measure of effective exposure, or if DBP may independently impact outcomes.

We conducted a nested case-control analysis within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study to examine whether circulating DBP concentration was prospectively associated with risk of renal cell carcinoma, and whether it modified the association with 25(OH)D.

Renal cell carcinoma cases (n=262) were matched 1:1 to controls on age (± 1 year) and date of blood collection (± 30 days). We estimated odds ratios and 95% confidence intervals of renal cell carcinoma risk by quartiles of 25(OH)D, DBP, and the molar ratio of 25(OH)D:DBP, a proxy for free circulating 25(OH)D.

Men with higher DBP concentrations were at significantly decreased risk of kidney cancer (Q4 vs. Q1: OR=0.17, 95% CI=0.08–0.33; p-trend<0.0001), a finding unchanged by adjustment for 25(OH)D.

Although we observed no association with total 25(OH)D, we found slightly increased risk with higher levels of estimated free 25(OH)D (Q4 vs. Q1 of the 25(OH)D:DBP ratio, OR=1.61, 95% CI=0.95–2.73; p-trend=0.09).

The strong protective association observed between higher circulating DBP concentration and kidney cancer risk requires replication but suggests a vitamin D-independent influence of DBP.

Conclusions (from PDF)
In this prospective analysis, men with higher serum concentrations of DBP experienced lower risk of renal cell carcinoma, whereas the 25(OH)D:DBP molar ratio, a proxy for free circulating 25(OH)D, showed a possible positive risk association. Combined, the two findings suggest that the DBP association may reflect a biological mechanism unrelated to vitamin D status. Our findings require confirmation in addi-tional studies, particularly in populations that include womenand nonsmokers. The relationship of circulating bound and free 25(OH)D and DBP with tissue-level availability of25(OH)D also warrants examination, and may help elucidate some of the conflicting results observed in epidemiologic studies of vitamin D and cancer.

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See also VitaminDWiki

• Search VitaminDWiki for "Kidney Cancer" 139 items as of Oct 2015
• All items in category DBP 99 items
• Hypothesis: Vitamin D Binding Protein limits vitamin D benefits outside of kidney too– Oct 2013

Overview Kidney and vitamin D contains the following summary

• FACT: The Kidneys are not the primary way to activate vitamin D; the tissues are
• FACT: When the Kidney has problems, there is less active vitamin D (Calcitriol) for the body
• FACT: When the Kidney has problems, there is increased death due to many factors - many of which are associated with lack of Calcitriol
• FACT: There are many ongoing intervention clinical trials trying to determine how much of what kind of vitamin D is needed to treat the problem
• FACT: One Randomized Controlled Trial has proven that Vitamin D treats CKD
• FACT: 38% of seniors have Chronic Kidney Disease and most are unaware of it CDC statistics 2020
• FACT: Taking extra Vitamin D, in various forms, does not cause health problems - even if poor kidney
• Suggestion: Increase vitamin D getting into body now - and increase co-factors so that the vitamin D can be better used
    Sun, UV lamp, Vitamin D supplement - probably > 5,000 IU,
  Nanoemulstion vitamin D (inside cheek, topically) gets activated Vitamin D to the cells without the need for healthy kidney, liver, or intestine
  Calcitriol - which bypasses the need for the kidney to activate vitamin D
    Problems with Calcitriol however: typically only lasts for a few hours, also, possible complications
      Update: Pre-cursor of active vitamin D made from plants is better than calcitriol – Sept 2012
• Category Kidney and Vitamin D contains 228 items