Relation between prediagnostic serum 25-hydroxyvitamin D level and incidence of breast, colorectal, and other cancers

Circulating vitamin D levels and colorectal cancer risk: A meta-analysis and systematic review of case-control and prospective cohort studies

The associations between circulating vitamin D concentrations and total and site-specific colorectal cancer (CRC) incidence have been examined in several epidemiological studies with overall inconclusive findings. The aim of this systematic review and meta-analysis of both case-control and prospective cohort studies was to evaluate the association between CRC and circulating levels of vitamin D. The main exposure and outcome were circulating total 25(OH)D and CRC, respectively, in the overall population (i.e., all subjects). Two reviewers, working independently, screened all the literature available to identify studies that met the inclusion criteria (e.g., case-control or prospective cohort studies, published in English, and excluding non-original papers). Data were pooled by the generic inverse variance method using a random or fixed effect model, as approriate. Heterogeneity was identified using the Cochran's Q-test and quantified by the I² statistic. Results were stratified by study design, sex, and metabolite of vitamin D. Sensitivity and subgroup analyses were also performed. A total of 28 original studies were included for the quantitative meta-analysis. Meta-analyses comparing the highest vs lowest categories, showed a 39% lower risk between levels of total 25(OH)D and CRC risk (OR (95% CI): 0.61 (0.52; 0.71); 11 studies) in case-control studies; whereas a 20% reduced CRC risk in prospective cohort studies (HR (95% CI): 0.80 (0.66; 0.97); 6 studies). Results in women mirrored main results, whereas results in men were non-significant in both analyses. Our findings support an inverse association between circulating vitamin D levels and CRC risk.

The African Female Breast Cancer Epidemiology Study Protocol

Breast cancer is now the commonest cancer in most sub-Saharan African countries. Few studies of the epidemiology and genomics of breast cancer and its molecular subtypes in these countries have been done. The African Female Breast Cancer Epidemiology (AFBRECANE) study, a part of the Human Heredity and Health in Africa (H3Africa) initiative, is designed to study the genomics and epidemiology of breast cancer and its molecular subtypes in Nigerian women. We link recruitment of breast cancer cases at study sites with population-based cancer registries activities to enable ascertainment of the incidence of breast cancer and its molecular subtypes. We use centralized laboratory processing to characterize the histopathological and molecular diagnosis of breast cancer and its subtypes using multiple technologies. By combining genome-wide association study (GWAS) data from this study with that generated from 12,000 women participating in our prospective cohort study of cervical cancer, we conduct GWAS of breast cancer in an entirely indigenous African population. We test associations between dietary intakes and breast cancer and focus on vitamin D which we measure using dietary intakes, serum vitamin D, and Mendelian randomization. This paper describes the AFBRECANE project, its design, objectives and anticipated contributions to knowledge and understanding of breast cancer.

Evaluation of the potential anticancer activity of different vitamin D metabolites on colorectal and breast cancer cell lines

OBJECTIVES

Vitamin D is very important for calcium and mineral metabolism, and many hypotheses appear to link sunlight exposure with cancer risk and prognosis. As many studies supported the antitumor effect of vitamin D we wanted to investigate the potential effect of multiple vitamin D metabolites.

METHODS

This study compared the anticancer effect of three inactive forms of vitamin D₃ which are; cholecalciferol, alfacalcidol, and calcifediol on two human cancer cell lines colorectal cancer (CaCo II) and breast cancer (MCF-7). All were examined after 24, 48, and 72 h continuous exposure using a colorimetric assay (MTT) seeded in 96-multiwell plates. Doxorubicin anticancer used as a standard agent for comparison, while normal skin fibroblast cells (HDFa) was used as our negative control. IC₅₀ values were calculated as indication of antitumor effect.

RESULTS

Broad-spectrum of cytotoxicity with IC₅₀ values ranging from 4 to 200 μM were found. Alfacalcidol was the most potent cytotoxic agents on colorectal cancer (CaCo II) and breast cancer (MCF-7) compared to cholecalciferol, and calcifediol. Both, alfacalcidol and calcifediol were more cytotoxic than cholecalciferol on the tested cell lines as they are partially active metabolites. Breast cancer (MCF-7) was the most sensitive to all metabolites at all-time intervals with the best IC₅₀ values of 4.35 μM ± 1.06 after 72 h continuous exposure of alfacalcidol.

CONCLUSIONS

Vitamin D metabolites are a potential option for cancer treatment along with or an alternative to chemo-therapeutics although extensive preclinical studies are required to prove this effect.

Clinical significance of serum 25 hydroxyvitamin D in breast cancer: An Indian scenario

Recent evidences suggest a protective mechanism of vitamin D signaling against breast cancer by the autocrine/paracrine manner and may modestly reduce the risk of breast cancer. Despite lots of sunshine, vitamin D deficiency is widespread in India. Moreover, there are limited studies from Indian population regarding circulatory 25(OH) D and breast cancer risk. Thus, the aim of the present study is to investigate circulatory 25(OH) D in relation to breast cancer risk and its association with various clinico-pathological parameters from Indian population. Total 297 subjects, comprising of 157 controls and 140 breast cancer patients were enrolled for the study. Circulatory 25(OH) D was analyzed by HPLC. Statistical analysis was carried out by SPSS software version 15. Further, subjects were categorized into severe, moderate, mild vitamin D deficiency and sufficiency. The prevalence of severe and moderate 25(OH) D deficiency was higher in breast cancer patients as compared to controls. Mean values of 25(OH) D were lower in breast cancer patients as compared to controls in mild, moderate and severe deficient groups (p = 0.07, p = 0.003 and p = 0.001). Moreover, 25(OH) D was significantly lower in postmenopausal breast cancer patients as compared to premenopausal breast cancer patients, particularly in severe deficient group. The levels of 25(OH) D were lower in ER and PR negative receptor status as compared to the positive receptor in severe deficient category (p = 0.06 and p = 0.09 respectively). Whereas, the mean values of 25(OH) D were lower in HER 2 negative receptor status as compared to positive receptor status in the moderate deficient category (p = 0.09). Further, severe deficient group showed significantly lower levels of 25(OH) Din TNBC as compared to luminal A subtype (p = 0.01). Thus, Results indicate that 25(OH) D deficiency might be associated with increased risk of breast cancer. Moreover, severe 25(OH) D deficiency is associated with aggressive behavior of breast cancer.

Reduced survival after autologous stem cell transplantation in myeloma and lymphoma patients with low vitamin D serum levels

High-dose chemotherapy (HDCT) with autologous stem cell transplantation (ASCT) is applied for consolidation in myeloma and relapsing lymphoma patients. Vitamin D (VitD) exerts effects during hematopoietic stem cell proliferation, differentiation and interactions with the immune system. VitD deficiency is frequent in patients with hematological malignancies, but its prognostic relevance after ASCT remains unclear. We investigated the effect of VitD serum levels in patients with lymphomas and myeloma at ASCT on progression-free (PFS) and overall survival (OS). The cohort (n = 183) was divided into two groups: 81 (44%) had VitD levels >52 nmol/L and 102 (56%) ≤52 nmol/L at ASCT. VitD levels >52 nmol/L were associated with better PFS (P = 0.0194) and OS (P = 0.011). Similarly, when evaluating myeloma patients alone, patients with lower VitD levels (≤52 nmol/L) had inferior PFS (P = 0.0412) and OS (P = 0.049). Finally, the multivariate analysis was consistent that varying VitD levels were significantly associated with OS (P = 0.0167), also when stratifying patients in groups with VitD levels > versus ≤52 nmol/L (P = 0.0421). Our data suggest that reduced serum VitD levels in myeloma and lymphoma patients undergoing HDCT/ASCT are associated with inferior outcome. Optimizing VitD levels before ASCT may be warranted.

Vitamin D and the skin: what should a dermatologist know?

Although first discovered in 1931, vitamin D has seen an increased interest in the scientific community over the past decades, including the dermatology field. Vitamin D promotes calcium and phosphorus absorption; however, the actions of vitamin D are not confined to bone. Indeed, there is now overwhelming and compelling scientific data that vitamin D plays a crucial role in a plethora of cellular function and in extra-skeletal health. Except for fatty fish livers, very few foods naturally contain vitamin D; and the major source of vitamin D comes from skin exposure to sunlight via ultraviolet B. Keratinocytes are unique in the body as not only do they provide the primary source of vitamin D for the body, but they also possess both the enzymatic machinery to metabolize the vitamin D produced to active metabolites. This has been referred to as the photoendocrine vitamin D system. Vitamin D regulates keratinocytes proliferation and differentiation; and plays a role in the defense against opportunistic infections. Multiple factors are linked to vitamin D status; and a growing number of dermatologic diseases has been linked to vitamin D status such as atopic dermatitis, psoriasis, vitiligo, and cutaneous cancers. In this article, we reviewed the potential determinants of vitamin D status, as its implications in dermatologic diseases.

Assessing the Effect of Vitamin D Replacement on Basal Cell Carcinoma Occurrence and Recurrence Rates in Patients with Vitamin D Deficiency

The study aimed to determine whether 25-OH vitamin D₃ deficiency is present in patients with diagnosed BCC, and the effect of vitamin D replacement on the rates of BCC recurrence in patients with 25-OH vitamin D₃ deficiency. In this prospective study, between 2012 and 2017, in the first stage, 25-OH vitamin D₃ levels of all patients diagnosed with BCC between 2012 and 2013 were evaluated. In the second stage between 2014 and 2015, we evaluated the 25-OH vitamin D₃ level of patients who had 25-OH vitamin D₃ level < 25 ng/mL. All the patients included in the second stage had BCC recurrence. In the third stage, the patients who were diagnosed 25-OH vitamin D₃ deficiency with BCC, between 2015 and 2017, were studied. The mean 25-OH vitamin D₃ level of the patients in the second stage was 10.12 ng/mL. Recurrence was observed in 9.64% of the patients in the second stage. The mean level of serum 25-OH vitamin D₃ in the third stage was 40.1 ng/mL, and 3.49% of these patients presented with recurrence. In all the patients as the initial diagnosis and following the 25-OH vitamin D₃ level in all the patients with BCC recurrence, maintaining 25-OH vitamin D₃ levels above 25 ng/mL can significantly reduce the recurrence rate.

Risk tradeoffs associated with traditional food advisories for Labrador Inuit

The traditional Inuit diet includes wild birds, fish and marine mammals, which can contain high concentrations of the neurotoxicant methylmercury (MeHg). Hydroelectric development may increase MeHg concentrations in traditional foods. Consumption advisories are often used to mitigate such risks and can result in reduced intake of traditional foods. Data from a dietary survey, MeHg exposure assessment and risk analysis for individuals in three Inuit communities in Labrador, Canada (n = 1145) in 2014 indicate reducing traditional food intake is likely to exacerbate deficiencies in n-3 polyunsaturated fatty acids and vitamins B12 and B2. Traditional foods accounted for < 5% of per-capita calories but up to 70% of nutrients consumed. Although consumption advisories could lower neurodevelopmental risks associated with an increase in MeHg exposure (90th-percentile ∆IQ = - 0.12 vs. - 0.34), they may lead to greater risks of cardiovascular mortality (90th-percentile increase: + 58% to + 116% vs. + 25%) and cancer mortality (90th-percentile increase + 2% to + 4% vs. no increase). Conversely, greater consumption of locally caught salmon mostly unaffected by hydroelectric flooding would lower all these risks (90th-percentile ∆IQ = + 0.4; cardiovascular risk: - 45%; cancer risk: - 1.4%). We thus conclude that continued consumption of traditional foods is essential for Inuit health in these communities.

Non-musculoskeletal benefits of vitamin D

The aim of this study is to determine and critically evaluate the plausible relationships of vitamin D with extra-skeletal tissues in humans. Severe vitamin D deficiency results in rickets in children and osteomalacia in adults; these beneficial effects in the musculoskeletal system and certain physiological functions are well understood. Nevertheless, mounting reports support additional beneficial effects of vitamin D, outside the musculoskeletal system. This review explores the recent advances in knowledge about the non-skeletal effects of vitamin D. Peer-reviewed papers were extracted from research databases using key words, to assess correlations between vitamin D and extra-skeletal diseases and conditions. As per the guidelines of the Preferred Reporting Items for Systematic Reviews (PRISMA); general interpretations of results are included; taking into consideration the broader evidence and implications. This review summarizes current knowledge of the effects of vitamin D status on extra-skeletal tissues with special attention given to relationships between vitamin D status and various diseases commonly affecting adults; the effects of intervention with vitamin D and exposure to sunlight. Evidence suggests that vitamin D facilitates the regulation of blood pressure; and cardiac; endothelial; and smooth muscle cell functions; playing an important role in cardiovascular protection. In addition; 1,25(OH)₂D improves immunity; subdues inflammation; and reduces the incidence and severity of common cancers; autoimmune diseases and infectious diseases. Almost all adequately powered; epidemiological and biological studies that use; adequate doses of vitamin D supplementation in D-deficient populations have reported favorable outcomes. These studies have concluded that optimizing 25(OH)D status improves the functionality of bodily systems; reduces comorbidities; improves the quality of life; and increases survival. Although accumulating evidence supports biological associations of vitamin D sufficiency with improved physical and mental functions; no definitive evidence exists from well-designed; statistically powered; randomized controlled clinical trials. Nevertheless, most studies point to significant protective effects of vitamin D in humans when the minimum 25(OH)D serum level exceeds 30ng/mL and is maintained throughout the year.

Vitamin D status in recurrent aphthous stomatitis

Introduction

Recurrent aphthous stomatitis (RAS) is a common chronic inflammatory oral mucosa disease with an unknown cause. However, dysregulation of the immune response seems to play an important role in this disease.

Aim

To evaluate the vitamin D status in RAS patients and its effects on RAS severity, given the likely immunomodulatory function of vitamin D in the human organism.

Material and methods

Sixty-six patients with RAS and 66 controls were examined. Immunomodulatory or immunosuppressive treatment and other ulcerative oral diseases were used as exclusion criteria. The severity of RAS was assessed according to the clinical classification of the disease, the number of lesions per flare-up and the length of intervals between the attacks. The serum vitamin D level was established in each participant.

Results

The mean serum vitamin D (25(OH)D) levels were found to be 16.81 ng/ml in the study group and 19.22 ng/ml in the control group, with no statistically significant difference between the two groups. In the study group, 5 (7.6%) participants were diagnosed with the “normal” vitamin D levels, while 16 (24.2%) had “insufficient” levels and 45 (68.2%) had “deficient” levels. The corresponding distribution in the control group was 8 (12.1%), 18 (27.3%) and 40 (60.6%), respectively. There was no statistical significance in the difference of vitamin D deficits between the study and the control groups. No correlation was detected between the severity of RAS and the serum vitamin D level.

Conclusions

Vitamin D does not seem to be a trigger factor for RAS occurrence and does not appear to influence the severity of the disease in the studied group.

Determination of Vitamin D Status in a Population of Ecuadorian Subjects

INTRODUCTION

Vitamin D is a preprohormone known to play a key role in phosphocalcic metabolism; its main source comes from the synthesis at the skin level by ultraviolet (UV) radiation.

OBJECTIVE

The purpose of this study was to determine the levels of vitamin D in an Ecuadorian population.

MATERIALS AND METHODS

Retrospective study of Ecuadorian subjects from the city of Guayaquil, who had an initial study of 25 (OH)-D serum, as the indicator of Vitamin D status, in the period of 2015-2016.

RESULTS

A total of 269 Ecuadorian subjects were analyzed, with a mean age of 54.73 ± 16.58; 85% (229) were females and 15% (41) males; mean vitamin D was 27.29 ± 10.12 ng/dl [6.41-88.74]; 70% of the population showed levels below 30 ng/dL of vitamin D, whereas only 30% (81) had normal values. 69% (185) had levels between 29 and 10 ng/dl and 1% (3) levels below 10 ng/dl. High levels of vitamin D were evidenced in the summer months in relation to the winter months.

CONCLUSION

It is evident that, despite the location of Ecuador and the intensity of UV rays it receives throughout the year, Ecuadorian subjects have insufficient levels of vitamin D.

25-Hydroxyvitamin D Status and Risk for Colorectal Cancer and Type 2 Diabetes Mellitus: A Systematic Review and Meta-Analysis of Epidemiological Studies

Epidemiological evidence suggests an association between low vitamin D status and risk for various outcomes including cardiovascular diseases, cancer, and type 2 diabetes mellitus (T2DM). Analyzing serum 25-hydroxyvitamin D [25(OH)D] is the most established means to evaluate an individual's vitamin D status. However, cutoff values for 25(OH)D insufficiency as well as for optimal 25(OH)D levels are controversial. This systematic review critically summarizes the epidemiological evidence regarding 25(OH)D levels and the risk for colorectal cancer and T2DM. The meta-analytical calculation revealed a pooled relative risk (RR) of 0.62 (CI 0.56-0.70; I² = 14.7%) for colorectal cancer and an RR of 0.66 (CI 0.61-0.73; I² = 38.6%) for T2DM when comparing individuals with the highest category of 25(OH)D with those in the lowest. A dose-response analysis showed an inverse association between 25(OH)D levels and RR for both outcomes up to concentrations of about 55 ng/mL for colorectal cancer and about 65 ng/mL for T2DM. At still higher 25(OH)D levels the RR increases slightly, consistent with a U-shaped association. In conclusion, a higher 25(OH)D status is associated with a lower risk for colorectal cancer and T2DM; however, this advantage is gradually lost as levels increase beyond 50-60 ng/mL.

Vitamin D Intake and Risk of Skin Cancer in US Women and Men

Previous studies suggested a protective effect of vitamin D against skin cancer development. However, epidemiologic studies on orally taken vitamin D and risk of skin cancer (basal cell carcinoma [BCC], squamous cell carcinoma [SCC], and melanoma) are few. We prospectively evaluated whether total, dietary and supplemental vitamin D intake were associated with skin cancer risk based on 63,760 women in the Nurses' Health Study (1984–2010) and 41,530 men in the Health Professionals Follow-up Study (1986–2010). Dietary information on vitamin D intake was assessed every 2 to 4 years during the follow-up and cumulative averaged intake was used. We used Cox proportional hazard models to compute the hazard ratios (HR) and 95% confidence intervals (CI). Pooled HR of cohort-specific results were calculated using a random-effects model. During the follow-up, we documented 20,840 BCC, 2,329 SCC and 1,320 melanoma cases. Vitamin D consumption was not associated with the risk of SCC or melanoma but was modestly positively associated with BCC; the pooled HRs of BCC for extreme quintiles of vitamin D intake were 1.10 (95%CI = 1.05–1.15; P_trend = 0.05) for total vitamin D and 1.13 (95% CI = 1.07 to 1.20; P_trend <0.01) for dietary vitamin D. Stratified analysis according to sun exposure related factors showed similar results. In conclusion, vitamin D intake was positively associated with risk of BCC, while null associations were found with SCC and melanoma. Our data do not support a beneficial role of orally taken vitamin D on skin cancer carcinogenesis.

Vitamin D derivatives enhance cytotoxic effects of H2O2 or cisplatin on human keratinocytes

Although the skin production of vitamin D is initiated by ultraviolet radiation type B (UVB), the role vitamin D plays in antioxidative or pro-oxidative responses remains to be elucidated. We have used immortalized human HaCaT keratinocytes as a model of proliferating epidermal cells to test the influence of vitamin D on cellular response to H2O2 or the anti-cancer drug, cisplatin. Incubation of keratinocytes with 1,25(OH)2D3 or its low calcemic analogues, 20(OH)D3, 21(OH)pD or calcipotriol, sensitized cells to ROS resulting in more potent inhibition of keratinocyte proliferation by H2O2 in the presence of vitamin D compounds. These results were supported by cell cycle and apoptosis analyses, and measurement of the mitochondrial transmembrane potentials (MMP), however some unique properties of individual secosteroids were observed. Furthermore, in HaCaT keratinocytes treated with H2O2, 1,25(OH)2D3, 21(OH)pD and calcipotriol stimulated the expression of SOD1 and CAT genes, but not SOD2, indicating a possible role of mitochondria in ROS-modulated cell death. 1,25(OH)2D3 also showed a short-term, protective effect on HaCaT keratinocytes, as exemplified by the inhibition of apoptosis and the maintenance of MMP. However, with prolonged incubation with H2O2 or cisplatin, 1,25(OH)2D3 caused an acceleration in the death of the keratinocytes. Therefore, we propose that lead vitamin D derivatives can protect the epidermis against neoplastic transformation secondary to oxidative or UV-induced stress through activation of vitamin D-signaling. Furthermore, our data suggest that treatment with low calcemic vitamin D analogues or the maintenance of optimal level of vitamin D by proper supplementation, can enhance the anticancer efficacy of cisplatin.

Relationship of low vitamin D status with positive, negative and cognitive symptom domains in people with first-episode schizophrenia

AIM

Deficient vitamin D levels are very common among Americans of all ages and ethnicities, but little is known about its prevalence or associated problems among those with schizophrenia.

METHODS

Stored plasma from 20 recent onset schizophrenia subjects and 20 matched healthy comparison subjects were analysed for 25 OH vitamin D, and related to measures of symptom severity and neurocognition.

RESULTS

There was no significant difference in mean 25 OH vitamin D between the schizophrenia and the healthy comparison subjects (28.2 standard deviation (SD) 12.6 ng mL(-1) vs. 29.9 SD 14.3 ng mL(-1) ), and about half the subjects in each group had insufficient levels (<30 ng mL(-1) ). Among psychosis subjects, greater severity of negative symptoms was correlated with lower vitamin D status (r = -0.55, P = 0.012); the correlations of overall symptom severity and positive symptom severity with 25 OH vitamin D levels approached significance (r = -0.42, P = 0.07 and r = -0.36, P = 0.12, respectively). There was no relationship of vitamin D with depressive symptoms. Among the schizophrenia subjects, lower 25 OH vitamin D levels were associated with more severe overall cognitive deficits (r = 0.56, P = 0.019).

CONCLUSION

This study found that lower vitamin D levels in schizophrenia subjects were associated with more severe negative symptoms and overall cognitive deficits. However, the cross-sectional design precludes any conclusions about whether low vitamin D status in fact causes more severe negative symptoms and cognitive impairments. No relationship was found between lower vitamin D levels and depressive symptoms.

Circulating 25-hydroxyvitamin D and risk of lung cancer: a dose-response meta-analysis

BACKGROUND

Mounting experimental evidence supports a protective effect of high 25-hydroxyvitamin D (25[OH]D), a good indicator of vitamin D status, on risk of various cancers including lung cancer. However, prospective observational studies examining the 25(OH)D-lung cancer association reported inconsistent findings. A dose-response meta-analysis was carried out to elucidate the subject.

METHODS

Potentially eligible studies were identified by searching PubMed and EMBASE databases, and by carefully reviewing the bibliographies of retrieved publications. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated using the random-effects model.

RESULTS

Thirteen reports from ten prospective studies were included, totaling 2,227 lung cancer events. Results of the meta-analysis showed a significant 5% (RR 0.95, 95% CI 0.91-0.99) reduction in the risk of lung cancer for each 10 nmol/L increment in 25(OH)D concentrations. This inverse association was not significantly modified by area, study duration, sex, methods for 25(OH)D measurement, baseline 25(OH)D levels, or quality score of included studies. There was evidence of a nonlinear relationship between 25(OH)D and risk of lung cancer (p-nonlinearity = 0.02), with the greatest reductions in risk observed at 25(OH)D of nearly 53 nmol/L, and remained protective until approximately 90 nmol/L. Further increases showed no significant association with cancer risk, but scanty data were included in the analyses of high-level 25(OH)D. There was no evidence of publication bias.

CONCLUSION

This dose-response meta-analysis of prospective studies suggests that 25(OH)D may be associated with reduced risk of lung cancer, in particular among subjects with vitamin D deficiencies.

Emphasizing the health benefits of vitamin D for those with neurodevelopmental disorders and intellectual disabilities

People with neurodevelopmental disorders and intellectual disabilities have much greater health care needs. Mainly staying indoors, such people generally have low 25-hydroxyvitamin D (25(OH)D) concentrations. The Vitamin D Task Force of the American Academy of Developmental Medicine and Dentistry (AADMD) reviewed the evidence of 25(OH)D concentrations that benefit the health of persons with developmental disabilities. Maintaining recommended optimal serum 25(OH)D concentrations year long will benefit skeletal development in infants, children, and adolescents, and benefit musculoskeletal health and neuromuscular coordination in adult patients, and decrease risk of falls. Maintaining optimal concentrations decreases risks and severities of autoimmune diseases, cardiovascular disease, many types of cancer, dementia, types 1 and 2 diabetes mellitus, and respiratory tract infections. Other benefits include improved dental and oral health and improved physical performance. The Task Force recommends that 25(OH)D concentrations for optimal health to be in the range of 75 to 125 nmol/L, which can be achieved using between 800 and 4000 IU/day vitamin D3 and sensible exposure to solar UVB radiation. The paper also discusses the potential risks of higher 25(OH)D concentrations, the evidence from and limitations of randomized controlled trials, and the recommendations by various groups and agencies.

Vitamin D and inflammation

Several studies found an inverse relationship between 25-hydroxyvitamin D [25(OH)D] and markers of inflammation. A controversy exists as to whether vitamin D lowers inflammation or whether inflammation lowers 25(OH)D concentrations. Certainly 25(OH)D concentrations fall after major surgery. However, is this due to inflammation lowering 25(OH)D or is 25(OH)D being metabolically cleared by the body to quell inflammation. We searched the literature and found 39 randomized controlled trials (RCT) of vitamin D and markers of inflammation. Seventeen found significantly reduced inflammatory markers, 19 did not, one was mixed and one showed adverse results. With few exceptions, studies in normal subjects, obesity, type 2 diabetics, and stable cardiovascular disease did not find significant beneficial effects. However, we found that 6 out of 7 RCTS of vitamin D3 in highly inflammatory conditions (acute infantile congestive heart failure, multiple sclerosis, inflammatory bowel disease, cystic fibrosis, SLE, active TB and evolving myocardial infarction) found significant reductions. We found baseline and final 25(OH)D predicted RCTs with significant reduction in inflammatory markers. Vitamin D tends to modestly lower markers of inflammation in highly inflammatory conditions, when baseline 25(OH)D levels were low and when achieved 25(OH)D levels were higher. Future inquiries should: recruit subjects with low baseline 25(OH)D levels, subjects with elevated markers of inflammation, subjects with inflammatory conditions, achieve adequate final 25(OH)D levels, and use physiological doses of vitamin D. We attempted to identify all extant randomized controlled trials (RCTs) of vitamin D that used inflammatory markers as primary or secondary endpoints.

Screening for vitamin D deficiency: a systematic review for the U.S. Preventive Services Task Force

BACKGROUND

Vitamin D deficiency has been associated with adverse health outcomes.

PURPOSE

To systematically review benefits and harms of vitamin D screening in asymptomatic adults.

DATA SOURCES

Ovid MEDLINE (through the third week of August 2014), Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews.

STUDY SELECTION

Randomized trials of screening for and treatment of vitamin D deficiency and case-control studies nested within the Women's Health Initiative.

DATA EXTRACTION

One investigator abstracted data, a second reviewed data for accuracy, and 2 investigators independently assessed study quality using predefined criteria.

DATA SYNTHESIS

No study examined the effects of vitamin D screening versus no screening on clinical outcomes. Vitamin D treatment was associated with decreased mortality versus placebo or no treatment (11 studies; risk ratio [RR], 0.83 [95% CI, 0.70 to 0.99]), although benefits were no longer seen after trials of institutionalized persons were excluded (8 studies; RR, 0.93 [CI, 0.73 to 1.18]). Vitamin D treatment was associated with possible decreased risk for having at least 1 fall (5 studies; RR, 0.84 [CI, 0.69 to 1.02]) and falls per person (5 studies; incidence rate ratio, 0.66 [CI, 0.50 to 0.88]) but not fractures (5 studies; RR, 0.98 [CI, 0.82 to 1.16]). Vitamin D treatment was not associated with a statistically significant increased risk for serious adverse events (RR, 1.17 [CI, 0.74 to 1.84]).

LIMITATION

Variability across studies in 25-hydroxyvitamin D assays and baseline levels, treatment doses, use of calcium, and duration of follow-up.

CONCLUSION

Treatment of vitamin D deficiency in asymptomatic persons might reduce mortality risk in institutionalized elderly persons and risk for falls but not fractures.

PRIMARY FUNDING SOURCE

Agency for Healthcare Research and Quality.

Vitamin D and skin cancer

Vitamin D signaling plays a key role in many important processes, including cellular proliferation, differentiation and apoptosis, immune regulation, hormone secretion and skeletal health. Furthermore, vitamin D production and supplementation have been shown to exert protective effects via an unknown signaling mechanism involving the vitamin D receptor (VDR) in several diseases and cancer types, including skin cancer. With over 3.5 million new diagnoses in 2 million patients annually, skin cancer is the most common cancer type in the United States. While ultraviolet B (UVB) radiation is the main etiologic factor for nonmelanoma skin cancer (NMSC), UVB also induces cutaneous vitamin D production. This paradox has been the subject of contradictory findings in the literature in regards to amount of sun exposure necessary for appropriate vitamin D production, as well as any beneficial or detrimental effects of vitamin D supplementation for disease prevention. Further clinical and epidemiological studies are necessary to elucidate the role of vitamin D in skin carcinogenesis.

Lack of association between serum 25-hydroxyvitamin D levels and cervical human papillomavirus infection in systemic lupus erythematosus

Our objective was to evaluate whether vitamin D deficiency is associated with cervical human papilloma virus (HPV) infection in women with SLE. This is a cross-sectional study of 67 women with SLE. A structured questionnaire was administered to ascertain the possible risk factors associated with cervical HPV infection. A gynaecological evaluation and cervical cytology screening were made. HPV detection and genotyping was made by PCR and linear array assay. Serum 25 hydroxyvitamin D levels were quantified by chemiluminescence immunoassay. Mean age and disease duration were 44.8 ± 10.6 and 42.5 ± 11.8 years, respectively. Demographic characteristics were similar in patients with and without deficiency (<20 ng/ml and ≥20 ng/ml). There were 28.4% of women with cervical HPV infection and 68.4% had high-risk HPV infections. Patients with 25 hydroxyvitamin D levels <20 ng/ml had a higher prevalence of cervical HPV infection than those with levels ≥20 ng/ml (30.7% vs. 25.8%; p = 0.72). We found no significant difference when high-risk HPV infection was evaluated (36.8% vs. 31.5%; p = 0.73). In conclusion, women with SLE have a high prevalence of vitamin D deficiency and cervical HPV infection. However, we found no association between vitamin D deficiency and cervical HPV.

Levels of serum 25-hydroxy-vitamin d in benign and malignant breast masses

BACKGROUND

The true association between breast cancer and vitamin D is currently under investigation. We compared serum 25-hydroxy-vitamin D levels in women with benign and malignant breast masses and controls.

MATERIALS AND METHODS

Levels of vitamin D were measured by electrochemiluminescense. Serum levels >35 ng/ml, 25-35 ng/ml, 12.5-25 ng/ml and <12.5 ng/ml were considered as normal, mild, moderate and severe vitamin D deficiency, respectively.

RESULTS

Overall, 364 women were included in the control, 172 in the benign and 136 in the malignant groups. The median serum vitamin D level was significantly lower in breast cancers than controls. Levels were also lower in malignant than benign cases and in benign cases than controls although statistically non-significant.

CONCLUSIONS

Multinomial logistic regression analysis showed that severe vitamin D deficiency causes a three-fold increase in the risk of breast cancer while this was not the case for moderate and mild deficiency.

Combination of lenalidomide with vitamin D3 induces apoptosis in mantle cell lymphoma via demethylation of BIK

Mantle cell lymphoma (MCL) is a currently incurable B-cell malignancy. Lenalidomide (Len) has been demonstrated to be one of the most efficient new treatment options. Because Len and 1α,25-dihydroxyvitamin (VD3) synergize to kill breast cancer cells, we investigated whether VD3 could increase the ability of Len to induce MCL cell death. While MCL cells were weakly sensitive to Len (1 μM), the addition of VD3 at physiological dose (100 nM) strongly increased cell death, accompanied by slowdown in cell cycle progression in MCL cell lines (n=4 out of 6) and primary samples (n=5 out of 7). The Len/VD3 treatment markedly increased the expression of the BH3-only BCL2-interacting killer (Bik) without affecting the expression of other Bcl-2 molecules. Immunoprecipitation assays demonstrated that Bik was free from anti-apoptotic partners, Bcl-2 and Bcl-x_L, in treated cells. Moreover, silencing of BIK prevented apoptosis induced by Len/VD3, confirming the direct involvement of Bik in cell death. Bik accumulation induced by Len/VD3 was related to an increase in BIK mRNA levels, which resulted from a demethylation of BIK CpG islands. The sensitivity of MCL cells to Len/VD3 was similar to the response to 5-azacytidine, which also induced demethylation of BIK CpG islands. These preclinical data provide the rationale to investigate the role of VD3 in vivo in the response to Len.

The trials and tribulations of vitamin D: time for the 'sunshine' vitamin to come in out of the cold - or just more broken promises?

We are presently faced with the competing notions of modern life being a 'state of vitamin D depletion', implying a widespread need to supplement with vitamin D, or, the opposite view, which is that the present evidence can only support at best selective targeted vitamin D intervention. This is important as there is evidence that over the last 40-50 years there were downwards global trends in serum 25(OH)D concentrations, while individual consumption of vitamin D as supplements rose. For this reason and many others, a large population-based interventional study, the VITAL trial, was designed to try to establish the health value of vitamin D supplementation. VITAL is a huge primary prevention trial looking at the effects of vitamin D repletion in preventing cancer and cardiovascular disease in a fundamentally healthy population. This may seem an unusual approach given that what we mostly know about vitamin D is that is has some effects on the skeleton. This review looks to explore current knowledge about vitamin D in health and disease, and at how this is now undergoing significant reappraisal and revision. We will carefully critique the VITAL study design to see if it will allow for the construction of the detailed portfolio of clinical evidence so urgently needed to allow us better to understand role of vitamin D supplementation in health and disease.

Review: the impacts of circulating 25-hydroxyvitamin D levels on cancer patient outcomes: a systematic review and meta-analysis

CONTEXT

Circulating levels of 25-hydroxyvitamin D [25(OH)D] may affect the prognosis of cancer patients; however, the epidemiological results are not consistent.

OBJECTIVE

To perform a meta-analysis of all published studies to assess the associations of circulating 25(OH)D levels measured at or near the time of diagnosis and outcomes for cancer patients.

DATA SOURCES

Searches of the PubMed and MEDLINE databases were performed and updated to December 2013.

STUDY SELECTION

Studies reporting an association between circulating 25(OH)D levels at or near the time of diagnosis and outcomes for the patients were included.

DATA EXTRACTION

Data extraction was performed independently by two authors, and conflicts were resolved by a third investigator.

DATA SYNTHESIS

Included in the meta-analysis were 25 studies with 17 332 cases. Significant associations between circulating 25(OH)D levels at or near the time of diagnosis and the outcomes for cancer patients were found. The pooled hazard ratio for the highest vs the lowest quartile of circulating 25(OH)D levels was 0.55 (95% confidence interval [CI] = 0.33-0.91) for overall survival of colorectal cancer patients, 0.63 (95% CI = 0.51-0.77) for breast cancer patients, and 0.48 (95% CI = 0.36-0.64) for lymphoma patients. Higher 25(OH)D levels were significantly associated with reduced cancer-specific mortality for patients with colorectal cancer (P = .005) and lymphoma (P < .001) and improved disease-free survival for patients with breast cancer (P < .001) or lymphoma (P < .05). A 10-nmol/L increment in circulating 25(OH)D levels conferred a hazard ratio of 0.96 (95% CI = 0.95-0.97) for overall survival of the cancer patients.

CONCLUSIONS

The results indicate that cancer patients with higher circulating 25(OH)D levels at or near the time of diagnosis have better outcomes.

Vitamin D transport proteins megalin and disabled-2 are expressed in prostate and colon epithelial cells and are induced and activated by all-trans-retinoic acid

Megalin and disabled-2 (Dab2) are essential for uptake of the 25-hydroxycholecalciferol (25D3)-vitamin D binding protein (DBP) complex in tissues. In the kidney, this mechanism regulates serum 25D3 levels and production of 1,25-dihydroxycholecalciferol (1,25D3) by CYP27B1 for systemic use. Previously, we showed that mammary epithelial cells expressing CYP27B1 express megalin and Dab2 and internalize DBP by endocytosis, indicating 25D3 was accessible for conversion to 1,25D3 in extra-renal tissues. Moreover, induction of megalin and Dab2 (protein and mRNA abundance) by all-trans-retinoic acid (RA) enhanced DBP uptake. This suggests megalin and Dab2 play a central role in uptake of vitamin D and may predict actions of vitamin D in extra-renal tissues. Here, we characterized megalin and Dab2 expression and uptake of DBP in transformed human prostate and colon epithelial cells. Megalin and Dab2 were expressed in prostate and colon epithelial cells, which was markedly enhanced following treatment with RA. Furthermore, DBP uptake was stimulated by low-dose RA supplementation in LNCaP, PC-3, and Caco-2 cells. Taken together, these are the first studies to our knowledge that have demonstrated modulated expression of megalin and Dab2, as well as an association between increased expression of endocytic proteins with DBP uptake in prostate and colon cells.

Occupational UV exposure of environmental agents in Valencia, Spain

Excessive exposure to ultraviolet radiation (UVR) is considered the most important environmental risk factor in the development of melanoma and skin cancer. Outdoor workers are among those with the highest risk from exposure to solar UVR, as their daily activities constantly expose them to this radiation source. A study was carried out in Valencia, Spain, in summer 2012 and involved a group of 11 workers for a period of six 2-day recordings. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure erythemal UVR received by environmental agents in the course of their daily work. Median 2-day UV exposure was 6.2 standard erythema dose (SED), with 1 SED defined as effective 100 J m(-2) when weighted with the Commission Internationale de L'Eclairage's (CIE) erythemal response function. These workers were found to receive a median of 8.3% total daily ambient ultraviolet erythemal radiation. Comparison with the occupational UV exposure limit showed that the subjects had received an erythemal UV dose in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

The relationship between 25-hydroxyvitamin D and homocysteine in asymptomatic adults

CONTEXT

Hyperhomocysteinemia is an independent risk factor for premature atherosclerosis and thromboembolism. 25-Hydroxyvitamin D [25(OH)D] may modulate the expression of genes involved in homocysteine metabolism.

OBJECTIVE

Little is known about the relationship between homocysteine and 25(OH)D. We hypothesized an inverse and nonlinear association between 25(OH)D and homocysteine.

DESIGN

We analyzed data from the continuous National Health and Nutrition Examination Survey 2001-2006 for asymptomatic adults (≥18 y).

SETTING

Linear regression models with spline adjusted for cardiovascular disease risk factors were used to explore nonlinearity.

MAIN OUTCOMES MEASURE

Mean change (β-coefficients with 95% confidence intervals) in homocysteine was reported per 10 ng/mL change in 25(OH)D.

RESULTS

Mean (SD) age and homocysteine levels of 14 630 participants were 47.2 (20) years and 8.8 (4.7) μmol/L, respectively, whereas the median (interquartile range) of 25(OH)D was 21 (15-27) ng/mL. Without using spline, we observed an inverse relation between homocysteine and 25(OH)D both in simple [-0.25 (-0.34 to -0.02) μmol/L] and multivariable [-0.13 (-0.18 to -0.01) μmol/L] regression. With spline, in a univariate model, an increase in 25(OH)D was associated with a significant decrease in homocysteine [-0.56 (-0.75 to -0.37) μmol/L] until 25(OH)D reaches but not if above its median (21 ng/mL). Similarly, in multivariable spline models, the inverse relationship between homocysteine and 25(OH)D remain significant [-0.49 (-0.67 to -0.31) μmol/L] only below the population median of 25(OH)D.

CONCLUSIONS

From a large community-based cohort of asymptomatic adults, we found an inverse relation between 25(OH)D and homocysteine among those with 25(OH)D concentration of 21 ng/mL or less. We did not observe any statistical decrease in homocysteine once 25(OH)D concentration rose above 21 ng/mL.

Chronical cervical infections and dysplasia (CIN I, CIN II): Vaginal vitamin D (high dose) treatment: A new effective method?

In a small praxis/ambulance study we evaluated data of 200 women with chronical recurrent cervical infections and with a cervix dysplasia (CIN 1, CIN 2). who got after the primary therapy a treatment with vitamin D vaginal suppositories (12.500 IU, 3 nights a week, for 6 weeks). We found that - when compared with the lactobacillus vaginal suppositories - the high dose vitamin D vaginal treatment might be more effective. Vitamin D showed very good anti-inflammatory effects. In the survey after six weeks therapy 79% of the women had “less vaginal problems,” “less discharge” and “less problems with the sexual intercourse.” Objectively after six weeks therapy only 7% of the patients still had bacterial and/or fungal vaginal infections that required a treatment. We found that vitamin D is reabsorbed by the vaginal mucosa, but the reabsorption may be individually very different. In the CIN 1 group we found six weeks after treatment good antidysplastic effects, in the CIN 2 group we often found no or only temporary antidysplastic effects. So this vaginal vitamin D treatment method might be an option for the therapy and prevention of chronical cervical infections and maybe of a cervic dysplasia CIN 1 (good antiinflammatory effects, antidysplastic effects). This small study is not representative. We need much bigger studies with much more dates and with a longer follow up. Caution: At the moment we do not know, if the vaginal vitamin D treatment with 12500 IE is possible in pregnancy. We have no experience. Therefore we recommend an effective contraception during the application.

Personal UV exposure for different outdoor sports

The aim of this paper is to measure UV exposure for three groups of amateur athletes in their training/recreational schedules using VioSpor personal dosimeters and we found that two of these groups exceeded the international UV threshold level for non-sun-adapted Mediterranean skin.

Does vitamin D sufficiency equate to a single serum 25-hydroxyvitamin D level or are different levels required for non-skeletal diseases?

Objective: Clarify the concept of vitamin D sufficiency, the relationship between efficacy and vitamin D status and the role of Vitamin D supplementation in the management of non-skeletal diseases. We outline reasons for anticipating different serum vitamin D levels are required for different diseases. Method: Review the literature for evidence of efficacy of supplementation and minimum effective 25-hydroxyvitamin D (25-OHD) levels in non-skeletal disease. Results: Evidence of efficacy of vitamin supplementation is graded according to levels of evidence. Minimum effective serum 25-OHD levels are lower for skeletal disease, e.g., rickets (25 nmol/L), osteoporosis and fractures (50 nmol/L), than for premature mortality (75 nmol/L) or non-skeletal diseases, e.g., depression (75 nmol/L), diabetes and cardiovascular disease (80 nmol/L), falls and respiratory infections (95 nmol/L) and cancer (100 nmol/L). Conclusions: Evidence for the efficacy of vitamin D supplementation at serum 25-OHD levels ranging from 25 to 100 nmol/L has been obtained from trials with vitamin D interventions that change vitamin D status by increasing serum 25-OHD to a level consistent with sufficiency for that disease. This evidence supports the hypothesis that just as vitamin D metabolism is tissue dependent, so the serum levels of 25-OHD signifying deficiency or sufficiency are disease dependent.

Molecular link between vitamin D and cancer prevention

The metabolite of vitamin D, 1α,25-dihydroxyvitamin D₃ (also known as calcitriol), is a biologically active molecule required to maintain the physiological functions of several target tissues in the human body from conception to adulthood. Its molecular mode of action ranges from immediate nongenomic responses to longer term mechanisms that exert persistent genomic effects. The genomic mechanisms of vitamin D action rely on cross talk between 1α,25-dihydroxyvitamin D₃ signaling pathways and that of other growth factors or hormones that collectively regulate cell proliferation, differentiation and cell survival. In vitro and in vivo studies demonstrate a role for vitamin D (calcitriol) in modulating cellular growth and development. Vitamin D (calcitriol) acts as an antiproliferative agent in many tissues and significantly slows malignant cellular growth. Moreover, epidemiological studies have suggested that ultraviolet-B exposure can help reduce cancer risk and prevalence, indicating a potential role for vitamin D as a feasible agent to prevent cancer incidence and recurrence. With the preventive potential of this biologically active agent, we suggest that countries where cancer is on the rise--yet where sunlight and, hence, vitamin D may be easily acquired--adopt awareness, education and implementation strategies to increase supplementation with vitamin D in all age groups as a preventive measure to reduce cancer risk and prevalence.

Solar UV exposure in construction workers in Valencia, Spain

Exposure to ultraviolet radiation (UVR) has long been recognized as the most important environmental risk factor for melanoma and skin cancer. Outdoor workers are among the groups most at risk from exposure to solar UVR in their daily activities. Sensitive spore-film filter-type personal dosimeters (VioSpor) were used to measure the biologically effective UVR received by construction workers in the course of their daily work. The study took place in Valencia, Spain, in July 2010 and involved a group of eight workers for a period of 5 days. The median UV exposure was 6.11 standard erythema dose (SED) per day, with 1 SED defined as effective 100 J/m(2) when weighted with the Commission Internationale de L'Eeclairage erythemal response function. These workers were found to receive a median of 13.9% of total daily ambient ultraviolet erythemal radiation (UVER). Comparison with the occupational UVR exposure limit showed that the subjects had received UVER exposure in excess of occupational guidelines, indicating that protective measures against this risk are highly advisable.

Benefits of ultraviolet-B irradiance and vitamin D in youth

A large and growing body of journal literature reports the health benefits of solar ultraviolet-B (UVB) irradiance and vitamin D. Most of the literature relates to the effects of vitamin D later in life, when chronic diseases are more likely to manifest and when the innate immune system is weaker, leading to increased rates of some infectious diseases. However, a significant body of literature exists on the health effects of solar UVB irradiance and serum 25-hydroxyvitamin D [25(OH)D] concentrations in youth. The goal of this paper is to review representative evidence of health benefits and risks of solar UVB irradiance and vitamin D for those aged from about 5 to 18 years. The topics discussed include physical development, athletic performance, infectious diseases, autoimmune diseases, metabolic syndrome, and cancer. Some of the effects of higher solar UVB irradiance and serum 25(OH)D concentrations are evident in youth, although some may become apparent later in life. This article is part of a Special Issue entitled 'Vitamin D Workshop'.

Solar UV radiation and cancer in young children

BACKGROUND

Studies have shown that higher solar UV radiation exposure (UVR) may be related to lower risk of some cancers in adults. Recently, an ecologic study reported lower risks of some cancers among children living in higher UVR cities and countries. In a large population-based case-control study in California, we tested the hypothesis that childhood cancers may be influenced by UVR.

METHODS

Cancers in children ages 0 to 5 years were identified from California Cancer Registry records for 1988 to 2007 and linked to birth certificate data. Controls were sampled from the birth certificates at a ratio of 20:1. Based on birth address, we assigned UVR exposure in units of Watt-hours/m(2) using a geostatistical exposure model developed with data from the National Solar Radiation Database.

RESULTS

For cases with UVR exposure of 5,111 Watt-hours/m(2) or above, we estimated a reduction in odds of developing acute lymphoblastic leukemia (OR: 0.89, 95% CI: 0.81-0.99), hepatoblastoma (OR: 0.69, 95% CI: 0.48-1.00), and non-Hodgkin's lymphoma (OR: 0.71, 95% CI: 0.50-1.02) adjusting for mother's age, mother's race, and child's year of birth. We also observed a small increase in odds for intracranial/intraspinal embryonal tumors (OR: 1.29, 95% CI: 1.01-1.65).

CONCLUSIONS

Our findings suggest that UVR during pregnancy may decrease the odds of some childhood cancers. Future studies should explore additional factors that may be correlated with UVR exposure and possibly include biomarkers of immune function and vitamin D.

IMPACT

This study shows protective associations of UVR with some childhood cancers.

Vitamin D: metabolism, molecular mechanisms, and mutations to malignancies

The potential protective effects of vitamin D against cutaneous carcinogenesis are still poorly understood. The inhibition, by vitamin D, of various cancers in in vitro and in vivo models has triggered detailed investigation of vitamin D effects on neoplastic behavior. Recent studies highlight that such neoplastic features as the tumor microenvironment, angiogenesis, DNA mutagenesis, and apoptosis are all connected to vitamin D metabolic pathways. This review discusses these connections. Vitamin D modulation of the cell cycle, DNA repair and apoptosis via its receptors (VDRs) may have a suppressive effect on skin cancer as some studies suggest. The regulation of multiple tumor signaling pathways by vitamin D may have an implication in cutaneous carcinogenesis and tumor progression to malignancy.

Serum 25-hydroxyvitamin D and breast cancer in the military: a case-control study utilizing pre-diagnostic serum

PURPOSE

The objective of this study was to ascertain whether a relationship exists between pre-diagnostic serum levels of 25-hydroxyvitamin D (25(OH)D) and risk of breast cancer in young women.

METHODS

About 600 incident cases of breast cancer were matched to 600 controls as part of a nested case-control study that utilized pre-diagnostic sera. Logistic regression was used to assess the relationship between serum 25(OH)D concentration and breast cancer risk, controlling for race and age.

RESULTS

According to the conditional logistic regression for all subjects, odds ratios for breast cancer by quintile of serum 25(OH)D from lowest to highest were 1.2, 1.0, 0.9, 1.1, and 1.0 (reference) (p trend = 0.72). After multivariate regression for subjects whose blood had been collected within 90 days preceding diagnosis, odds ratios for breast cancer by quintile of serum 25(OH)D from lowest to highest were 3.3, 1.9, 1.7, 2.6, and 1.0 (reference) (p trend = 0.09).

CONCLUSIONS

An inverse association between serum 25(OH)D concentration and risk of breast cancer was not present in the principal analysis, although an inverse association was present in a small subgroup analysis of subjects whose blood had been collected within 90 days preceding diagnosis. Further prospective studies of 25(OH)D and breast cancer risk are needed.

Decreasing 25-hydroxy-vitamin D levels account for portion of the effect of increasing body mass index on breast cancer mortality

SCOPE

Increased body mass index (BMI) and decreased serum vitamin D are both known to be associated with increased mortality from breast cancer. However, vitamin D levels are lower in obese individuals in general. Recent studies have sought to determine whether serum vitamin D levels can account for some of the association between higher BMI and increased risk for breast cancer and found that low vitamin D levels in the overweight and obese account for up to 40% of the BMI-attributable risk of developing breast cancer.

METHODS AND RESULTS

Here we reviewed the literature to determine if a similar relationship exists between vitamin D, BMI, and breast cancer mortality. Utilizing previously reported independent associations of low vitamin D and high BMI to increases in breast cancer mortality, as well as the known decrement in vitamin D per unit increase in BMI, we estimated that low vitamin D levels may be responsible for roughly 16% of the increased mortality from breast cancer in overweight and obese patients.

CONCLUSION

Although this is a relatively small proportion of the effect of obesity, supplements to increase serum vitamin D levels may represent a way to reduce obesity-associated disparities in breast cancer mortality.

Current progress in using vitamin D and its analogs for cancer prevention and treatment

Vitamin D has long been known for its physiological role in mineral homeostasis through its actions on the intestines, kidneys, parathyroid glands and bone. However, recent observations of antiproliferative, prodifferentiating and antiangiogenic effects elicited by the bioactive form of vitamin D (1,25[OH](2)D(3)) in a broad range of cancers is less well understood. Here, we review the increasing epidemiological and experimental evidence that supports the development of 1,25(OH)(2)D(3) and vitamin D analogs as preventative and therapeutic anticancer agents. Furthermore, this review summarizes the preclinical and clinical studies of vitamin D and its analogs over the past decade, indicating the current problems of dose-limiting toxicity from hypercalcemia and large interpatient variability in pharmacokinetics. A better understanding of how genetic variants influence vitamin D status should not only improve cancer risk predictions, but also promote the development of vitamin D analogs with more specific actions to improve therapeutic outcomes.

An ecological study of cancer mortality rates in California, 1950-64, with respect to solar UVB and smoking indices

<u>

PURPOSE

</u> This paper addresses whether nonmelanoma skin cancer (NMSC) mortality rates can serve as a useful index of population ultraviolet-B (UVB) irradiance and vitamin D production in a manner that affects the risk of internal cancers <u>

METHODS

</u> This analysis uses the ecological study approach with cancer mortality rate data from 19 state economic areas in California. This paper uses age-adjusted data for those aged 40 y or older. Two additional indices for solar UVB doses were also used: latitude and surface UVB doses for July 1992 from the total ozone mapping spectrometer. Lung cancer mortality rates served as the index of the health effects of smoking<u>

RESULTS

</u> Significant inverse correlations with NMSC mortality rate in multiple linear regression analyses were found during the period 1950-64 for eight types of cancer for males: bladder, brain, colon, gastric, prostate, and rectal cancer; multiple myeloma; and non-Hodgkin lymphoma. No similar results emerged for females with respect to all three UVB indices. Their NMSC mortality rates averaged 60% lower than those for males. Lung cancer mortality rates were directly correlated with three types of cancer for males: laryngeal, oral, and renal. No significant correlations with NMSC mortality rates appeared for later periods<u>

CONCLUSIONS

</u> NMSC mortality rates were found inversely correlated with internal cancers for males in the period 1950-64. After that period, no further such correlations were found. The reasons may hypothetically include reduced NMSC mortality rates, high immigration rates, movement from rural to urban locations and reduced solar UVB irradiance.

Role of solar UVB irradiance and smoking in cancer as inferred from cancer incidence rates by occupation in Nordic countries

A large body of evidence indicates that solar ultraviolet-B (UVB) irradiance and vitamin D reduce the risk of incidence and death for many types of cancer. However, most of that evidence comes from midlatitude regions, where solar UVB doses are generally high in summer. Data on cancer standardized incidence ratios (SIRs) by sex and 54 occupation categories based on 1.4 million male and 1.36 million female cancer cases for 1961–2005 in the five Nordic countries provide the basis for an ecological study of the role of solar UVB in the risk of many types of cancer at high latitudes. Lip cancer SIRs less lung cancer SIRs for men was the best index of solar UVB dose, which was weakly inversely correlated with both melanoma and nonmelanoma skin cancer (NMSC) SIRs. Lung cancer SIRs were used as the index of the effects of smoking. For men, the UVB index was significantly inversely correlated with 14 types of internal cancer—bladder, breast, colon, gallbladder, kidney, laryngeal, liver, lung, oral, pancreatic, pharyngeal, prostate, rectal and small intestine cancer. For women, the same UVB index was inversely correlated with bladder, breast and colon cancer. These results generally agree with findings from other studies. These results provide more support for the UVB-vitamin D-cancer hypothesis and suggest that widespread fear of chronic solar ultraviolet (UV) irradiance may be misplaced.