Circulating levels of 25-hydroxyvitamin D and prostate cancer prognosis

Role of N6‑methyladenosine in the pathogenesis, diagnosis and treatment of prostate cancer (Review)

Prostate cancer (PCa) affects males of all racial and ethnic groups, and leads to higher rates of mortality in those belonging to a lower socioeconomic status due to the late detection of the disease. PCa affects middle‑aged males between the ages of 45 and 60 years, and is the highest cause of cancer‑associated mortality in Western countries. As the most abundant and common mRNA modification in higher eukaryotes, N6‑methyladenosine (m6A) is widely distributed in mammalian cells and influences various aspects of mRNA metabolism. Recent studies have found that abnormal expression levels of various m6A regulators significantly affect the development and progression of various types of cancer, including PCa. The present review discusses the influence of m6A regulatory factors on the pathogenesis and progression of PCa through mRNA modification based on the current state of research on m6A methylation modification in PCa. It is considered that the treatment of PCa with micro‑molecular drugs that target the epigenetics of the m6A regulator to correct abnormal m6A modifications is a direction for future research into current diagnostic and therapeutic approaches for PCa.

Association Between Pretreatment Blood 25-Hydroxyvitamin D Level and Survival Outcomes in Patients With Clinically Localized Prostate Cancer: An Updated Meta-Analysis

Studies on the prognostic value of the blood 25-hydroxyvitamin D level have yielded controversial results in prostate cancer (PCa) patients. This updated meta-analysis aimed to evaluate the association between pretreatment 25-hydroxyvitamin D level with survival outcomes among patients with clinically localized PCa. PubMed, Web of Science, and Embase databases were searched to identify studies evaluating the association of pretreatment 25-hydroxyvitamin D level with PCSM and all-cause mortality among clinically localized PCa patients. Ten cohort studies with 10,394 patients were identified. The meta-analysis revealed that PCa patients with the lowest 25-hydroxyvitamin D levels had an increased risk of PCSM (adjusted hazard ratio [HR] 1.52; 95% confidence interval [CI] 1.26-1.83; p < 0.001) and all-cause mortality (adjusted HR 1.31; 95% CI 1.00-1.90; p = 0.047) compared to those with higher reference 25-hydroxyvitamin D level. Subgroup analyses based on different sample sizes, follow-up duration, and adjusted times of blood draw also exhibited a significant association of vitamin D deficiency with the risk of PCSM. Lower pretreatment level of 25-hydroxyvitamin D may be an independent predictor of reduced survival in patients with clinically localized PCa. Measuring the pretreatment blood 25-hydroxyvitamin D level can provide valuable information for risk stratification of survival outcomes in these patients.

Post-Diagnostic Dietary and Lifestyle Factors and Prostate Cancer Recurrence, Progression, and Mortality

PURPOSE OF REVIEW

This study aimed to summarize evidence published between 1999 and June 2020 examining diet and lifestyle after prostate cancer (PC) diagnosis in relation to risk of biochemical recurrence, PC progression, and PC-specific mortality.

RECENT FINDINGS

Secondary prevention is an important research area in cancer survivorship. A growing number of studies have reported associations between post-diagnostic modifiable behaviors and risk of PC outcomes. Evidence on modifiable lifestyle factors and PC remains limited. Where multiple studies exist, findings are often mixed. However, studies consistently suggest that smoking and consumption of whole milk/high-fat dairy are associated with higher risk of PC recurrence and mortality. In addition, physical activity and ½ to 1 glass of red wine/day have been associated with lower risk of recurrence and PC-specific mortality. Greater inclusion of racially/ethnically diverse groups in future research is necessary to understand these relationships in populations most impacted by adverse PC outcomes.

Vitamin D levels and the risk of prostate cancer and prostate cancer mortality

BACKGROUND

Vitamin D has a role in bone turnover and potentially bone-metastatic spread of prostate cancer (PCa). The aim of this observational study was to address the association between levels of serum vitamin D, diagnosis of PCa and subsequent mortality in men who underwent a biopsy of the prostate.

METHODS

All men who underwent prostatic biopsy in the Danish PCa Registry (DaPCaR) and who had a serum vitamin D measurement during the period 2004 to 2010 (n = 4,065) were identified. Men were categorized by clinical cut-offs based on seasonally adjusted serum vitamin D levels in <25 (deficient), 25-50 (insufficient), 50-75 (sufficient) and >75 nmol/L (high) serum vitamin D. Logistic regression model for association between vitamin D and risk of PCa diagnosis and multivariate survival analyses were applied.

RESULTS

No association between serum vitamin D and risk of PCa was found. Overall survival was lowest for serum vitamin D deficiency and a significantly higher PCa specific mortality (HR: 2.37, 95%CI: 1.45-3.90, p < .001) and other cause mortality (HR: 2.08, 95%CI: 1.33-3.24, p = .001) was found for PCa patients with serum vitamin D deficiency compared to serum vitamin D sufficiency.

CONCLUSION

No association was found between serum vitamin D categories and risk of PCa in men who underwent biopsy of the prostate. Men with PCa and serum vitamin D deficiency had a higher overall and PCa specific mortality compared to men with a sufficient level of serum vitamin D.

Circulating Vitamin D and Selenium Levels and Outcome in Prostate Cancer Patients: Lessons from the MARTINI-Lifestyle Cohort

BACKGROUND

Dietary agents, in particular vitamin D (Vit D) and selenium, are widely used by prostate cancer (PCa) patients to improve cancer outcomes.

OBJECTIVE

To investigate whether plasma Vit D and selenium levels prior to radical prostatectomy (RP) are associated with worse pathologic tumor characteristics and increased risk of disease recurrence.

DESIGN, SETTING, AND PARTICIPANTS

A total of 3849 men with PCa scheduled for RP in the Martini-Klinik at the University Hospital Hamburg-Eppendorf, Hamburg, Germany, between January 2014 and December 2018 were included in this study.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Age, and clinical and laboratory values were collected prior to RP. Biochemical recurrence (BCR) was defined as prostate-specific antigen (PSA) ≥0.2 μg/l and rising after RP. Kaplan-Meier plots depicted BCR-free survival. Cox regression models (adjusted for age, preoperative PSA, pT stage, pN stage, pGG, surgical margin status, and year of surgery) tested the relationship between oncologic outcomes and Vit D and selenium levels.

RESULTS AND LIMITATIONS

Median plasma Vit D and selenium levels were 19.3 and 71 μg/l, respectively. Circulating Vit D and selenium levels correlated inversely with PSA values. Histologic grade, pT stage, and pN stage were not associated with Vit D and selenium levels at the time of RP. In the overall cohort, BCR-free survival at 3 yr of follow-up was 82.9%. When stratified according to median Vit D levels, BCR-free survival at 3 yr of follow-up was 82.7% and 83.0% (p ≤ 0.59). Upon stratification according to median selenium levels, BCR-free survival was 82.2% and 83.7% (p = 0.19). In a multivariable Cox regression model predicting BCR, lower Vit D and selenium levels were not independent predictors of BCR.

CONCLUSIONS

Plasma Vit D and selenium levels prior to RP were not associated with BCR-free survival.

PATIENT SUMMARY

The results of the MARTINI-Lifestyle cohort could not show a correlation between the occurrence of biochemical recurrence of prostate cancer after radical prostatectomy and the serum levels of vitamin D and selenium. A recommendation should therefore be made to compensate for a potential deficiency and not with the expectation of a reduction in the risk of progression.

Vitamin D-Induced Molecular Mechanisms to Potentiate Cancer Therapy and to Reverse Drug-Resistance in Cancer Cells

Increasing interest in studying the role of vitamin D in cancer has been provided by the scientific literature during the last years, although mixed results have been reported. Vitamin D deficiency has been largely associated with various types of solid and non-solid human cancers, and the almost ubiquitous expression of vitamin D receptor (VDR) has always led to suppose a crucial role of vitamin D in cancer. However, the association between vitamin D levels and the risk of solid cancers, such as colorectal, prostate and breast cancer, shows several conflicting results that raise questions about the use of vitamin D supplements in cancer patients. Moreover, studies on vitamin D supplementation do not always show improvements in tumor progression and mortality risk, particularly for prostate and breast cancer. Conversely, several molecular studies are in agreement about the role of vitamin D in inhibiting tumor cell proliferation, growth and invasiveness, cell cycle arrest and inflammatory signaling, through which vitamin D may also regulate cancer microenvironment through the activation of different molecular pathways. More recently, a role in the regulation of cancer stem cells proliferation and short non-coding microRNA (miRNAs) expression has emerged, conferring to vitamin D a more crucial role in cancer development and progression. Interestingly, it has been shown that vitamin D is able not only to potentiate the effects of traditional cancer therapy but can even contribute to overcome the molecular mechanisms of drug resistance—often triggering tumor-spreading. At this regard, vitamin D can act at various levels through the regulation of growth of cancer stem cells and the epithelial–mesenchymal transition (EMT), as well as through the modulation of miRNA gene expression. The current review reconsiders epidemiological and molecular literature concerning the role of vitamin D in cancer risk and tumor development and progression, as well as the action of vitamin D supplementation in potentiating the effects of drug therapy and overcoming the mechanisms of resistance often triggered during cancer therapies, by critically addressing strengths and weaknesses of available data from 2010 to 2020.

Post-treatment levels of plasma 25- and 1,25-dihydroxy vitamin D and mortality in men with aggressive prostate cancer

Vitamin D may reduce mortality from prostate cancer (PC). We examined the associations of post-treatment plasma 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D concentrations with PC mortality. Participants were PC cases from the New South Wales Prostate Cancer Care. All contactable and consenting participants, at 4.9 to 8.6 years after diagnosis, were interviewed and had plasma 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)₂D) measured in blood specimens. Cox regression allowing for left-truncation was used to calculate adjusted mortality hazards ratios (HR) and 95% confidence intervals (95% CI) for all-cause and PC-specific mortality in relation to vitamin D levels and other potentially-predictive variables. Of the participants (n = 111; 75·9% response rate), there were 198 deaths from any cause and 41 from PC in the study period. Plasma 25(OH)D was not associated with all-cause or PC-specific mortality (p-values > 0·10). Plasma 1,25(OH)₂D was inversely associated with all-cause mortality (HR for highest relative to lowest quartile = 0·45; 95% CI: 0·29-0·69), and PC-specific mortality (HR = 0·40; 95% CI: 0·14-1·19). These associations were apparent only in men with aggressive PC: all-cause mortality HR = 0·28 (95% CI·0·15-0·52; p-interaction = 0·07) and PC-specific mortality HR = 0·26 (95% CI: 0·07-1.00). Time spent outdoors was also associated with lower all-cause (HR for 4^th relative to 1^st exposure quartile = 0·42; 95% CI: 0·24-0·75) and PC-specific (HR = 0·48; 95% CI: 0·14-1·64) mortality, although the 95% CI for the latter was wide. The inverse association between post-treatment plasma 1,25(OH)₂D levels and all-cause and PC-specific mortality in men with aggressive PC, suggest a possible beneficial effect of vitamin D supplementation in these men.

Diet and Lifestyle in Prostate Cancer

A variety of diet and lifestyle factors have been studied with respect to prostate cancer risk in large, prospective cohort studies. In spite of this work, and in contrast to other common cancers, few modifiable risk factors have been firmly established as playing a role in prostate cancer. There are several possible explanations for the lack of well-established risk factors. First, prostate cancer has among the highest heritability of all common cancers; second, early life exposures may play an important role in risk, rather than mid- and later-life exposures assessed in most epidemiological studies. Finally, prostate-specific antigen (PSA) screening plays a critical role in prostate cancer detection and incidence rates, which has important implications for epidemiological studies.Among modifiable risk factors, smoking and obesity are consistently associated with higher risk specifically of advanced prostate cancer. There is also considerable evidence for a positive association between dairy intake and overall prostate cancer risk, and an inverse association between cooked tomato/lycopene intake and risk of advanced disease. Several other dietary factors consistently associated with risk in observational studies, including selenium and vitamin E, have been cast into doubt by results from clinical trials. Results for other well-studied dietary factors, including fat intake, red meat, fish, vitamin D, soy and phytoestrogens are mixed.In practical terms, men concerned with prostate cancer risk should be encouraged to stop smoking, be as physically active as possible, and achieve or maintain a healthy weight. These recommendations also have the advantage of having a positive impact on risk of type 2 diabetes, cardiovascular disease, and other chronic diseases. Reducing dairy intake while increasing consumption of fish and tomato products is also reasonable advice.

Circulating vitamin D level and mortality in prostate cancer patients: a dose-response meta-analysis

Previous studies investigating the association of circulating 25-hydroxyvitamin D level with prognosis of prostate cancer yielded controversial results. We conducted a dose-response meta-analysis to elucidate the relationship. PubMed and EMBASE were searched for eligible studies up to July 15, 2018. We performed a dose-response meta-analysis using random-effect model to calculate the summary hazard ratio (HR) and 95% CI of mortality in patients with prostate cancer. Seven eligible cohort studies with 7808 participants were included. The results indicated that higher vitamin D level could reduce the risk of death among prostate cancer patients. The summary HR of prostate cancer-specific mortality correlated with an increment of every 20 nmol/L in circulating vitamin D level was 0.91, with 95% CI 0.87-0.97, P = 0.002. The HR for all-cause mortality with the increase of 20 nmol/L vitamin D was 0.91 (95% CI: 0.84-0.98, P = 0.01). Sensitivity analysis suggested the pooled HRs were stable and not obviously changed by any single study. No evidence of publications bias was observed. This meta-analysis suggested that higher 25-hydroxyvitamin D level was associated with a reduction of mortality in prostate cancer patients and vitamin D is an important protective factor in the progression and prognosis of prostate cancer.

Reduced vitamin D receptor (VDR) expression and plasma vitamin D levels are associated with aging-related prostate lesions

BACKGROUND

Protective roles have been proposed for vitamin D in prostate cancer, which has the advanced age as the major risk factor. However, little is known about the expression of the vitamin D receptor (VDR) in the aging prostate and its association with the development of epithelial lesions that affect tissue homeostasis and may precede prostate tumors.

METHODS

VDR expression in the prostatic complex of young adults to senile Wistar rats, a natural model to study age-related prostatic disorders, was evaluated by immunohistochemical, Western blotting, and image-assisted analyzes. Results were correlated with the plasma levels of vitamin D and testosterone, the occurrence of punctual histopathological changes in the aging prostate, and the expression of retinoid X receptors (RXR).

RESULTS

VDR was widely distributed in the prostatic complex at all ages analyzed, with the highest immunoexpression found in basal epithelial cells. As the animals aged, VDR levels increased, except in punctual areas with intraepithelial proliferation, metaplasia, or proliferative inflammatory atrophy, which had reduced expression of this receptor concomitantly with increased cell proliferation. Interestingly, RXR expression in the aging prostate was similar to that found for its partner VDR, indicating that components of the VDR/RXR complex required for vitamin D signaling are affected in aging-related prostatic lesions. Moreover, plasma vitamin D levels declined at the same ages when prostatic alterations appeared. Although circulating levels of testosterone also decreased with aging, the changes observed in the components of the vitamin D system were not correlated with androgens.

CONCLUSIONS

Our data indicate that the aging prostate suffers from an imbalance on the intricate mechanism of tissue regulation by the vitamin D responsive system. We argue that the status of VDR expression might be determinant for the development of histopathological alterations in the aging prostate, which include premalignant lesions.

Vitamin D and Cancer Risk and Mortality: State of the Science, Gaps, and Challenges

There has been substantial enthusiasm recently regarding the potential role of vitamin D in the primary and secondary prevention of cancer. Laboratory studies demonstrate a range of anticarcinogenic effects for vitamin D compounds, but human studies have yielded little consistent evidence supporting a protective association. Higher circulating levels of vitamin D (i.e., 25-hydroxyvitamin D or 25(OH)D) appear to be associated with reduced risk of colorectal and bladder malignancies, but higher risk of prostate and possibly pancreatic cancers, with no clear association for most other organ sites examined. Despite there being no official institutional recommendations regarding the use of vitamin D supplements for cancer prevention, screenings for vitamin D deficiency and vitamin D supplement use have increased substantially over the past decade. These widespread practices demonstrate that population sociobehavioral changes are often adopted before scientifically well-informed policies and recommendations are available. This review critically examines the currently available epidemiologic literature regarding the associations between circulating 25(OH)D, vitamin D supplementation, and vitamin D-related genetic variation and cancer risk and mortality, with a particular emphasis on prospective studies. We identify several important gaps in our scientific knowledge that should be addressed in order to provide sufficient reproducible data to inform evidence-based recommendations related to optimal 25(OH)D concentrations (and any role for vitamin D supplementation) for the primary and secondary prevention of cancer. With few exceptions, such recommendations cannot be made at this time.

Vitamin D Receptor Signaling and Cancer

The vitamin D receptor (VDR) binds the secosteroid hormone 1,25(OH)₂D₃ with high affinity and regulates gene programs that control a serum calcium levels, as well as cell proliferation and differentiation. A significant focus has been to exploit the VDR in cancer settings. Although preclinical studies have been strongly encouraging, to date clinical trials have delivered equivocal findings that have paused the clinical translation of these compounds. However, it is entirely possible that mining of genomic data will help to refine precisely what are the key anticancer actions of vitamin D compounds and where these can be used most effectively.

An update of research evidence on nutrition and prostate cancer

BACKGROUND

Prostate cancer (PCa) remains a leading cause of mortality in US and other countries. Preclinical and clinical studies have examined the role of nutrition and dietary intake on the incidence and progression of PCa with mixed results.

OBJECTIVE

The objective of this chapter is to provide an update of recent published literature and highlight progress in the field.

MAIN FINDINGS

Low carbohydrate intake, soy protein, ω3 fat, green teas, tomatoes and tomato products and the herbal mixture-zyflamend showed promise in reducing PCa risk or progression. On the contrary, a higher animal fat intake and a higher β-carotene status may increase risk. A "U" shape relationship may exist between folate, vitamin C, vitamin D and calcium with PCa risk. Conclusion Despite the inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa remains promising. Maintaining a healthy body weight and following a healthy dietary pattern including antioxidant rich fruits and vegetables, reduced animal fat and refined carbohydrates, should be encouraged.

CONCLUSION

Despite the inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa remains promising. Maintaining a healthy body weight and following a healthy dietary pattern including antioxidant rich fruits and vegetables, reduced animal fat and refined carbohydrates, should be encouraged.

The impact of vitamin D pathway genetic variation and circulating 25-hydroxyvitamin D on cancer outcome: systematic review and meta-analysis

BACKGROUND

Vitamin D has been linked with improved cancer outcome. This systematic review and meta-analysis investigates the relationship between cancer outcomes and both vitamin D-related genetic variation and circulating 25-hydroxyvitamin D (25OHD) concentration.

METHODS

A systematic review and meta-analysis of papers until November 2016 on PubMed, EMBASE and Web of Science pertaining to association between circulating vitamin D level, functionally relevant vitamin D receptor genetic variants and variants within vitamin D pathway genes and cancer survival or disease progression was performed.

RESULTS

A total of 44 165 cases from 64 studies were included in meta-analyses. Higher 25OHD was associated with better overall survival (hazard ratio (HR=0.74, 95% CI: 0.66-0.82) and progression-free survival (HR=0.84, 95% CI: 0.77-0.91). The rs1544410 (BsmI) variant was associated with overall survival (HR=1.40, 95% CI: 1.05-1.75) and rs7975232 (ApaI) with progression-free survival (HR=1.29, 95% CI: 1.02-1.56). The rs2228570 (FokI) variant was associated with overall survival in lung cancer patients (HR=1.29, 95% CI: 1.0-1.57), with a suggestive association across all cancers (HR=1.26, 95% CI: 0.96-1.56).

CONCLUSIONS

Higher 25OHD concentration is associated with better cancer outcome, and the observed association of functional variants in vitamin D pathway genes with outcome supports a causal link. This analysis provides powerful background rationale to instigate clinical trials to investigate the potential beneficial effect of vitamin D in the context of stratification by genotype.

miR-145 mediates the antiproliferative and gene regulatory effects of vitamin D3 by directly targeting E2F3 in gastric cancer cells

VitaminD3 signaling is involved in inhibiting the development and progression of gastric cancer (GC), while the active vitamin D metabolite 1-alpha,25-dihydroxyvitamin D3 (1,25(OH)₂D₃)-mediated gene regulatory mechanisms in GC remain unclear. We found that miR-145 is induced by 1,25(OH)₂D₃ in a dose- and vitamin D receptor (VDR)-dependent manner in GC cells. Inhibition of miR-145 reverses the antiproliferative effect of 1,25(OH)₂D₃. Furthermore, miR-145 expression was lower in tumors compared with matched normal samples and correlated with increased the E2F3 transcription factor protein staining. Overexpression of miR-145 inhibited colony formation, cell viability and induced cell arrest in S-phase in GC cells by targeting E2F3 and CDK6. miR-145 inhibition consistently abrogates the 1,25(OH)₂D₃-mediated suppression of E2F3, CDK6, CDK2 and CCNA2 genes. Altogether, our results indicate that miR-145 mediates the antiproliferative and gene regulatory effects of vitamin D3 in GC cells and might hold promise for prognosis and therapeutic strategies for GC treatment.

Circulating 25-Hydroxyvitamin D and Prostate Cancer Survival

BACKGROUND

Recent epidemiologic evidence suggests that higher circulating vitamin D does not protect against prostate cancer and, in fact, may increase the risk of developing this malignancy. However, few studies have examined the most clinically relevant outcome, prostate cancer mortality.

METHODS

We examined prediagnostic serum 25-hydroxy-vitamin D (25(OH)D) and prostate cancer survival in a cohort of 1,000 cases in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study. During 23 years of follow-up, 363 men died from their disease. Cox proportional hazards models were used to estimate the hazard ratio (HR) and 95% confidence interval (CI) of death from prostate cancer by season-specific quintile of 25(OH)D. Multivariable models were adjusted for age, physical activity, cigarettes per day, and family history of prostate cancer.

RESULTS

Men with higher serum 25(OH)D were less likely to die from their prostate cancer (Q5 vs. Q1 HR, 0.72; 95% CI, 0.52-0.99; Ptrend = 0.006). This finding was independent of stage or grade at diagnosis and appeared restricted to men who survived longer (survived <3.3 years: Q5 vs. Q1 HR, 0.95; 95% CI, 0.61-1.50; Ptrend, 0.53; survived ≥3.3 years: Q5 vs. Q1 HR, 0.53; 95% CI, 0.34-0.85; Ptrend, 0.0002).

CONCLUSIONS

In this population of men diagnosed with prostate cancer, higher serum 25(OH)D years prior to diagnosis was associated with longer prostate cancer survival.

IMPACT

In light of inconsistent evidence regarding the role of vitamin D in the development of prostate cancer, the present findings regarding the most clinically relevant prostate cancer outcome, disease-specific mortality, could have important public health implications. Cancer Epidemiol Biomarkers Prev; 25(4); 665-9. ©2016 AACR.

Vitamin D, PTH, and calcium in relation to survival following prostate cancer

PURPOSE

Epidemiological studies suggest that low levels of vitamin D constitute a risk factor for prostate cancer. However, the results are conflicting, perhaps because prostate cancer is a very heterogeneous disease. More recent studies have focused on cancer progression and mortality. Vitamin D is closely related to both calcium metabolism and parathyroid hormone (PTH) levels, and all three factors have been implicated in prostate cancer.

METHODS

We examined the associations between pre-diagnostic serum levels of vitamin D (25OHD), PTH, and calcium and mortality among 943 participants within the Malmö Diet and Cancer Study, who were diagnosed with prostate cancer. The mean time from diagnosis until the end of followup was 9.1 years (SD 4.5), and the mean time from inclusion until end of follow-up was 16.6 years (SD 4.9). The analytes were divided into quartiles, and the risk of death from prostate cancer was analyzed using Cox proportional hazard analysis, yielding hazards ratios (HR) with 95 % confidence intervals. The models were adjusted for season and year of inclusion, age at baseline, age at diagnosis, body mass index (BMI), and tumor characteristics (TNM and Gleason score).

RESULTS

We observed a trend toward a lower prostate-specific mortality with 25OHD >85 nmol/L in the unadjusted analysis. This became statistically significantly in the third quartile of 25OHD (85-102 nmol/L) compared to the first (<68 nmol/L), HR 0.54 (0.34-0.85) when adjusting for age, time of inclusion, and BMI. The association was further strengthened when adjusted for age at diagnosis, Gleason score, and TNM classification with a HR in Q3 0.36 (0.22-0.60). p for trend was 0.03. Regarding calcium, there was a significantly lower HR for the second quartile (2.35-2.39 mmol/L) compared to the first (≤2.34 mmol/L) with a HR of 0.54 (0.32-0.86) in the unadjusted analysis. However, this association disappeared when adjusting for tumor characteristics. There were no associations between levels of PTH and prostate cancer mortality.

CONCLUSION

This study shows that levels of pre-diagnostic vitamin D above 85 nmol/L may improve survival in men with prostate cancer.

Vitamin D and Colorectal, Breast, and Prostate Cancers: A Review of the Epidemiological Evidence

Over the past two decades, the question of whether vitamin D has a role in cancer incidence, progression, and mortality has been studied in detail. Colorectal, breast, and prostate cancers have been a particular area of focus; together, these three malignancies account for approximately 35% of cancer cases and 20% of cancer deaths in the United States, and as such are a major public health concern. Herein, we review and synthesize the epidemiological research regarding vitamin D, as measured by the biomarker 25-hydroxycholecalciferol [25(OH)D], and the incidence, progression, and mortality of these cancers. Overall, the results of observational studies of the relationship between 25(OH)D and colorectal cancer have revealed a consistent inverse association for incidence and mortality; while for breast cancer, results have generally demonstrated a relationship between higher 25(OH)D and lower risk for progression and mortality. In contrast, randomized, double-blind clinical trials conducted to date have generally failed to support these findings. For prostate cancer, there is no convincing evidence of an association between 25(OH)D and incidence, and inconsistent data for progression and mortality, though results of one open label clinical trial suggest that supplementation with 4000 IU/d of vitamin D3 may inhibit progression of the disease. Nonetheless, until the results of additional ongoing randomized, double-blind clinical trials are reported, it will be difficult to ascertain if vitamin D itself is related to a reduction in risk for some cancer endpoints, or whether high concentrations of the vitamin D biomarker 25(OH)D may instead serve as a marker for an overall beneficial risk factor profile.

The relationship between circulating 25-hydroxyvitamin D and survival in newly diagnosed advanced non-small-cell lung cancer

BACKGROUND

Serum 25-hydroxyvitamin D [25(OH)D], the major circulating form of vitamin D used for evaluating the vitamin D status of patients, has been associated with survival in a variety of cancers with conflicting evidence. We aimed to investigate this association in newly diagnosed advanced non-small-cell lung cancer (NSCLC) patients.

METHODS

This was a consecutive cohort of 359 newly diagnosed stages III-IV NSCLC patients who underwent a baseline serum 25(OH)D evaluation prior to receiving any treatment at our institution between January 2008 and December 2010. We used the vitamin D categories of "deficient (<20 ng/ml)" and "not deficient (> = 20 ng/ml)". Cox regression was used to evaluate the prognostic significance of serum 25(OH)D after adjusting for relevant confounders.

RESULTS

Mean age at diagnosis was 57.4 years. Of the 359 patients, 151 (42.1 %) were deficient in vitamin D at the time of diagnosis. The median survival in deficient and not deficient cohorts was 11.7 and 12.8 months respectively (p = 0.06). Season of diagnosis, performance status, smoking status and hospital location significantly predicted vitamin D status. On univariate Cox analysis, gender, stage of disease, hospital location, histologic subtype, subjective global assessment (SGA), performance status, smoking status, body mass index and serum albumin were significantly associated with survival (p <0.05 for all). On multivariate Cox analysis, six variables demonstrated statistically significant associations with survival: stage of disease, hospital location, histologic subtype, SGA, smoking status and serum albumin (p <0.05 for all). Serum vitamin D, which was borderline significant in univariate analysis, lost its significance in multivariate analysis.

CONCLUSIONS

We found season of diagnosis, performance status and smoking history to be predictive of vitamin D status. Consistent with previously published research in advanced NSCLC, we did not find any significant association between pre-treatment serum 25(OH)D and survival in our patients.

Risk of prostate cancer in African-American men: Evidence of mixed effects of dietary quercetin by serum vitamin D status

BACKGROUND

African-American (AA) men experience higher rates of prostate cancer (PCa) and vitamin D (vitD) deficiency than white men. VitD is promoted for PCa prevention, but there is conflicting data on the association between vitD and PCa. We examined the association between serum vitD and dietary quercetin and their interaction with PCa risk in AA men.

METHODS

Participants included 90 AA men with PCa undergoing treatment at Howard University Hospital (HUH) and 62 controls participating in HUH's free PCa screening program. We measured serum 25-hydroxy vitD [25(OH)D] and used the 98.2 item Block Brief 2000 Food Frequency Questionnaires to measure dietary intake of quercetin and other nutrients. Case and control groups were compared using a two-sample t-test for continuous risk factors and a Fisher exact test for categorical factors. Associations between risk factors and PCa risk were examined via age-adjusted logistic regression models.

RESULTS

Interaction effects of dietary quercetin and serum vitD on PCa status were observed. AA men (age 40-70) with normal levels of serum vitD (>30 ng/ml) had a 71% lower risk of PCa compared to AA men with vitD deficiency (OR = 0.29, 95%CI: 0.08-1.03; P = 0.055). In individuals with vitD deficiency, increased dietary quercetin showed a tendency toward lower risk of PCa (OR = 0.91, 95%CI: 0.82-1.00; P = 0.054, age-adjusted) while men with normal vitD were at elevated risk (OR = 1.23, 95%CI: 1.04-1.45).

CONCLUSION

These findings suggest that AA men who are at a higher risk of PCa may benefit more from vitD intake, and supplementation with dietary quercetin may increase the risk of PCa in AA men with normal vitD levels. Further studies with larger populations are needed to better understand the impact of the interaction between sera vitD levels and supplementation with quercetin on PCa in AA men.

Circulating 25-hydroxyvitamin D and survival in women with ovarian cancer

BACKGROUND

Vitamin D status might be associated with cancer survival. Survival after ovarian cancer is poor, but the association with vitamin D has rarely been examined.

OBJECTIVE

We evaluated the association between serum 25-hydroxyvitamin D [25(OH)D], a marker of vitamin D status, and ovarian cancer survival.

DESIGN

Participants were women with invasive ovarian cancer diagnosed between 2002 and 2005 who participated in the Australian Ovarian Cancer Study. Serum samples, collected at diagnosis (n = 670) or after completion of primary treatment and before recurrence (n = 336), were assayed for 25(OH)D. Sociodemographic, dietary, and lifestyle data came from questionnaires self-completed at recruitment, and clinical and survival data were from medical records, supplemented by linkage to the Australian National Death Index (October 2011). Cox proportional hazards regression was used to estimate HRs and 95% CIs for the association between circulating 25(OH)D and survival.

RESULTS

Overall, 59% of the women died during follow-up, with 95% of deaths resulting from ovarian cancer. Circulating 25(OH)D concentrations (mean: 44 nmol/L) were significantly associated with age, state of residence, season of blood collection, and body mass index but not with tumor histology, stage or grade, or comorbidities. Higher 25(OH)D concentrations at diagnosis were significantly associated with longer survival (adjusted HR: 0.93; 95% CI: 0.88, 0.99 per 10 nmol/L), but there was no significant association with progression-free survival or for 25(OH)D measured after primary treatment.

CONCLUSIONS

In our cohort, higher serum 25(OH)D concentrations at diagnosis were associated with longer survival among women with ovarian cancer. If confirmed in other studies, this suggests that vitamin D status at diagnosis may be an independent predictor of prognosis. Furthermore, if the association is found to be causal, improving vitamin D status may improve ovarian cancer survival rates.

Circulating vitamin D, vitamin D-related genetic variation, and risk of fatal prostate cancer in the National Cancer Institute Breast and Prostate Cancer Cohort Consortium

BACKGROUND

Evidence from experimental animal and cell line studies supports a beneficial role for vitamin D in prostate cancer (PCa). Although the results from human studies have been mainly null for overall PCa risk, there may be a benefit for survival. This study assessed the associations of circulating 25-hydroxyvitamin D (25(OH)D) and common variations in key vitamin D-related genes with fatal PCa.

METHODS

In a large cohort consortium, 518 fatal cases and 2986 controls with 25(OH)D data were identified. Genotyping information for 91 single-nucleotide polymorphisms (SNPs) in 7 vitamin D-related genes (vitamin D receptor, group-specific component, cytochrome P450 27A1 [CYP27A1], CYP27B1, CYP24A1, CYP2R1, and retinoid X receptor α) was available for 496 fatal cases and 3577 controls. Unconditional logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs) for the associations of 25(OH)D and SNPs with fatal PCa. The study also tested for 25(OH)D-SNP interactions among 264 fatal cases and 1169 controls.

RESULTS

No statistically significant relationship was observed between 25(OH)D and fatal PCa (OR for extreme quartiles, 0.86; 95% CI, 0.65-1.14; P for trend = .22) or the main effects of the SNPs and fatal PCa. There was evidence suggesting that associations of several SNPs, including 5 related to circulating 25(OH)D, with fatal PCa were modified by 25(OH)D. Individually, these associations did not remain significant after multiple testing; however, the P value for the set-based test for CYP2R1 was .002.

CONCLUSIONS

Statistically significant associations were not observed for either 25(OH)D or vitamin D-related SNPs with fatal PCa. The effect modification of 25(OH)D associations by biologically plausible genetic variation may deserve further exploration.

The association between pre-treatment serum 25-hydroxyvitamin D and survival in newly diagnosed stage IV prostate cancer

Background/Aims

Emerging evidence in the literature suggests a positive association between serum 25-hydroxyvitamin D [25(OH)D], a standard indicator of vitamin D status, and survival in certain types of cancer. We investigated this relationship in newly diagnosed stage IV prostate cancer patients.

Methods

A consecutive cohort of 125 newly diagnosed stage IV prostate cancer patients underwent a baseline serum 25(OH)D evaluation prior to receiving any treatment at our institution between January 2008 and December 2011. We used the vitamin D categories of “deficient (<20 ng/ml)”, “insufficient (20 to 32 ng/ml)”, and “sufficient (>32 ng/ml)”. Cox regression was used to evaluate the prognostic significance of serum 25(OH)D after adjusting for relevant confounders.

Results

Mean age at diagnosis was 60 years. Of the 125 patients, 32 (25.6%) were deficient, 49 (39.2%) were insufficient and 44 (35.2%) were sufficient in vitamin D at the time of diagnosis. The median survival in deficient, insufficient and sufficient cohorts was 47.8, 44.0 and 52.6 months respectively (p = 0.60). On univariate analysis, four variables demonstrated a statistically significant association with survival: nutritional status, bone metastasis, corrected serum calcium and serum albumin (p<0.05 for all). On multivariate analysis, five variables demonstrated statistically significant associations with survival: hospital location, age, bone metastasis, serum albumin and corrected serum calcium (p<0.05 for all). Serum vitamin D status was not significant on either univariate or multivariate analysis.

Conclusion

Contrary to previously published research, we found no significant association between pre-treatment serum 25(OH)D and survival in newly diagnosed stage IV prostate cancer patients. The lack of a significant association between serum vitamin D and survival in our study could perhaps be due to the fact that the disease was far too advanced in our patients for vitamin D levels to have any impact on prognosis.

Nutrition, dietary interventions and prostate cancer: the latest evidence

Prostate cancer (PCa) remains a leading cause of mortality in US men and the prevalence continues to rise world-wide especially in countries where men consume a 'Western-style' diet. Epidemiologic, preclinical and clinical studies suggest a potential role for dietary intake on the incidence and progression of PCa. 'This minireview provides an overview of recent published literature with regard to nutrients, dietary factors, dietary patterns and PCa incidence and progression. Low carbohydrates intake, soy protein, omega-3 (w-3) fat, green teas, tomatoes and tomato products and zyflamend showed promise in reducing PCa risk or progression. A higher saturated fat intake and a higher β-carotene status may increase risk. A 'U' shape relationship may exist between folate, vitamin C, vitamin D and calcium with PCa risk. Despite the inconsistent and inconclusive findings, the potential for a role of dietary intake for the prevention and treatment of PCa is promising. The combination of all the beneficial factors for PCa risk reduction in a healthy dietary pattern may be the best dietary advice. This pattern includes rich fruits and vegetables, reduced refined carbohydrates, total and saturated fats, and reduced cooked meats. Further carefully designed prospective trials are warranted.

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.

Prostate cancer and the influence of dietary factors and supplements: a systematic review

Background

Prostate cancer is the second most common cause of cancer worldwide after lung cancer. There is increasing evidence that diet and lifestyle plays a crucial role in prostate cancer biology and tumourigenesis. Prostate cancer itself represents a good model of cancer in which to look for chemopreventive agents due to the high disease prevalence, slowly progressive nature, and long latency period. Dietary agents have gained considerable attention, often receiving much publicity in the media.

Aim

To review the key evidence available for potential chemopreventive nutrients.

Methods

The methodology for this review involved a PubMed search from 1990 to 2013 using the key-words “diet and prostate cancer”, “nutrition and prostate cancer”, “dietary factors and prostate cancer”, “prostate cancer epidemiology”, “prostate cancer prevention”, “prostate cancer progression”.

Results

Red meat, dietary fat and milk intake should be minimised as they appear to increase the risk of prostate cancer. Fruit and vegetables and polyphenols may be preventive in prostate cancer, but further studies are needed to draw more solid conclusions and to clarify their role in patients with an established diagnosis of prostate cancer. Selenium and vitamin supplements cannot be advocated for the prevention of prostate cancer and indeed higher doses may be associated with a worse prognosis. There is no specific evidence regarding benefits of probiotics or prebiotics in prostate cancer.

Conclusions

From the wealth of evidence available, many recommendations can be made although more randomised control trials are required. These need to be carefully designed due to the many confounding factors and heterogeneity of the population.

Vitamin D, intermediary metabolism and prostate cancer tumor progression

Epidemiological data have demonstrated an inverse association between serum vitamin D3 levels, cancer incidence and related mortality. However, the effects of vitamin D on prostate cancer biology and its utility for prevention of prostate cancer progression are not as well-defined. The data are often conflicting: some reports suggest that vitamin D3 induces apoptosis in androgen dependent prostate cancer cell lines, while others suggest that vitamin D3 only induces cell cycle arrest. Recent molecular studies have identified an extensive synergistic crosstalk between the vitamin D- and androgen-mediated mRNA and miRNA expression, adding an additional layer of post-transcriptional regulation to the known VDR- and AR-regulated gene activation. The Warburg effect, the inefficient metabolic pathway that converts glucose to lactate for rapid energy generation, is a phenomenon common to many different types of cancer. This process supports cell proliferation and promotes cancer progression via alteration of glucose, glutamine and lipid metabolism. Prostate cancer is a notable exception to this general process since the metabolic switch that occurs early during malignancy is the reverse of the Warburg effect. This "anti-Warburg effect" is due to the unique biology of normal prostate cells that harbor a truncated TCA cycle that is required to produce and secret citrate. In prostate cancer cells, the TCA cycle activity is restored and citrate oxidation is used to produce energy for cancer cell proliferation. 1,25(OH)2D3 and androgen together modulates the TCA cycle via transcriptional regulation of zinc transporters, suggesting that 1,25(OH)2D3 and androgen maintain normal prostate metabolism by blocking citrate oxidation. These data demonstrate the importance of androgens in the anti-proliferative effect of vitamin D in prostate cancer and highlight the importance of understanding the crosstalk between these two signaling pathways.