Vitamin D3 supplementation, low-risk prostate cancer, and health disparities

Emerging perspectives: unraveling the anticancer potential of vitamin D3

Vitamin D3, a fat-soluble vitamin known for its critical function in calcium homeostasis and bone health, is gaining interest for its anticancer properties. Observational studies have suggested a negative relationship between vitamin D levels and the incidence of some malignancies throughout the years, prompting substantial investigation to find its anticancer effects. The purpose of this comprehensive review is to investigate the diverse function of vitamin D3 in cancer prevention and therapy. We explored the molecular mechanism underlying its effects on cancer cells, which range from cell cycle control and death to angiogenesis and immune response modulation. Insights from in vitro and in vivo studies provide valuable evidence supporting its anticancer potential. Furthermore, we look at epidemiological and clinical studies that investigate the relationship between vitamin D3 levels and cancer risk or treatment results. Vitamin D3 supplementation's safety profile and cost-effectiveness increase its attractiveness as an adjuvant therapy in conjunction with traditional treatment regimens. Our critical review of the current literature provides an in-depth understanding of vitamin D3's anticancer effect, covering the obstacles and possibilities in realizing its promise for cancer prevention and therapy. The findings of this study might pave the way for the development of innovative treatment techniques that take use of the advantages of vitamin D3 to fight cancer and improve patient care. As research progresses, a better understanding of vitamin D3's anticancer processes will surely simplify its incorporation into personalized cancer care techniques, hence enhancing patient outcomes in the battle against cancer.

Controlling Chronic Diseases and Acute Infections with Vitamin D Sufficiency

Apart from developmental disabilities, the prevalence of chronic diseases increases with age especially in those with co-morbidities: vitamin D deficiency plays a major role in it. Whether vitamin D deficiency initiates and/or aggravates chronic diseases or vice versa is unclear. It adversely affects all body systems but can be eliminated using proper doses of vitamin D supplementation and/or safe daily sun exposure. Maintaining the population serum 25(OH)D concentration above 40 ng/mL (i.e., sufficiency) ensures a sound immune system, minimizing symptomatic diseases and reducing infections and the prevalence of chronic diseases. This is the most cost-effective way to keep a population healthy and reduce healthcare costs. Vitamin D facilitates physiological functions, overcoming pathologies such as chronic inflammation and oxidative stress and maintaining broader immune functions. These are vital to overcoming chronic diseases and infections. Therefore, in addition to following essential public health and nutritional guidance, maintaining vitamin D sufficiency should be an integral part of better health, preventing acute and chronic diseases and minimize their complications. Those with severe vitamin D deficiency have the highest burdens of co-morbidities and are more vulnerable to developing complications and untimely deaths. Vitamin D adequacy improves innate and adaptive immune systems. It controls excessive inflammation and oxidative stress, generates antimicrobial peptides, and neutralizes antibodies via immune cells. Consequently, vitamin D sufficiency reduces infections and associated complications and deaths. Maintaining vitamin D sufficiency reduces chronic disease burden, illnesses, hospitalizations, and all-cause mortality. Vulnerable communities, such as ethnic minorities living in temperate countries, older people, those with co-morbidities, routine night workers, and institutionalized persons, have the highest prevalence of vitamin D deficiency-they would significantly benefit from vitamin D and targeted micronutrient supplementation. At least now, health departments, authorities, and health insurance companies should start assessing, prioritizing, and encouraging this economical, non-prescription, safe micronutrient to prevent and treat acute and chronic diseases. This approach will significantly reduce morbidity, mortality, and healthcare costs and ensure healthy aging.

Vitamin D, a Regulator of Androgen Levels, Is Not Correlated to PSA Serum Levels in a Cohort of the Middle Italy Region Participating to a Prostate Cancer Screening Campaign

Prostate cancer (PCa) is the most common non-cutaneous malignancy in men worldwide, and it represents the fifth leading cause of death. It has long been recognized that dietary habits can impact prostate health and improve the benefits of traditional medical care. The activity of novel agents on prostate health is routinely assessed by measuring changes in serum prostate-specific antigen (PSA) levels. Recent studies hypothesized that vitamin D supplementation reduces circulating androgen levels and PSA secretion, inhibits cell growth of the hormone-sensitive PCa cell lines, counteracts neoangiogenesis and improves apoptosis. However, the results are conflicting and inconsistent. Furthermore, the use of vitamin D in PCa treatments has not achieved consistently positive results to date. In order to assess the existence of a correlation between the PSA and 25(OH)vitamin D levels as widely hypothesized in the literature, we analyzed the serum PSA and 25(OH)vitamin D concentration on a cohort of one hundred patients joining a PCa screening campaign. Additionally, we performed medical and pharmacological anamnesis and analyzed lifestyle, as sport practice and eating habits, by administering a questionnaire on family history. Although several studies suggested a protective role of vitamin D in PCa onset prevention and progression, our preliminary results revealed a clear absence of correlation between the serum vitamin D and PSA concentration levels, suggesting that vitamin D has no impact on PCa risk. Further investigations enrolling a huge number of patients are needed with particular attention to vitamin D supplementation, calcium intake, solar radiation that influences vitamin D metabolism and other potential indicators of health to confirm the absence of correlation observed in our study.

Racial disparities in prostate cancer: A complex interplay between socioeconomic inequities and genomics

The largest US cancer health disparity exists in prostate cancer, with Black men having more than a two-fold increased risk of dying from prostate cancer compared to all other races. This disparity is a result of a complex network of factors including socioeconomic status (SES), environmental exposures, and genetics/biology. Inequity in the US healthcare system has emerged as a major driver of disparity in prostate cancer outcomes and has raised concerns that the actual incidence rates may be higher than current estimates. However, emerging studies argue that equalizing healthcare access will not fully eliminate racial health disparities and highlight the important role of biology. Significant differences have been observed in prostate cancer biology between various ancestral groups that may contribute to prostate cancer health disparities. These differences include enhanced androgen receptor signaling, increased genomic instability, metabolic dysregulation, and enhanced inflammatory and cytokine signaling. Immediate actions are needed to increase the establishment of adequate infrastructure and multi-center, interdisciplinary research to bridge the gap between social and biological determinants of prostate cancer health disparities.

A Systems Approach to Interrogate Gene Expression Patterns in African American Men Presenting with Clinically Localized Prostate Cancer

Simple Summary

Men of African origin have a 2–3 times greater chance of developing prostate cancer than those of European origin, and of patients that are diagnosed with the disease, men of African descent are 2 times more likely to die compared to white men. Men of African origin are still greatly underrepresented in genetic studies and clinical trials. This, unfortunately, means that new discoveries in cancer treatment are missing key information on the group with a greater chance of mortality. The objective of this study was to increase our knowledge of prostate cancer in men undergoing a prostate biopsy. We carried out RNA sequencing of biopsy specimens and examined racial differences in prostate gene expression. A gene expression signature was uncovered which separated the men based on their race. Furthermore, within men of African descent this signature separated men with the most severe clinical characteristics.

Abstract

An emerging theory about racial differences in cancer risk and outcomes is that psychological and social stressors influence cellular stress responses; however, limited empirical data are available on racial differences in cellular stress responses among men who are at risk for adverse prostate cancer outcomes. In this study, we undertook a systems approach to examine molecular profiles and cellular stress responses in an important segment of African American (AA) and European American (EA) men: men undergoing prostate biopsy. We assessed the prostate transcriptome with a single biopsy core via high throughput RNA sequencing (RNA-Seq). Transcriptomic analyses uncovered impacted biological pathways including PI3K-Akt signaling pathway, Neuroactive ligand-receptor interaction pathway, and ECM-receptor interaction. Additionally, 187 genes mapping to the Gene Ontology (GO) terms RNA binding, structural constituent of ribosome, SRP-dependent co-translational protein targeting to membrane and the biological pathways, translation, L13a-mediated translational silencing of Ceruloplasmin expression were differentially expressed (DE) between EA and AA. This signature allowed separation of AA and EA patients, and AA patients with the most severe clinical characteristics. AA patients with elevated expression levels of this genomic signature presented with higher Gleason scores, a greater number of positive core biopsies, elevated dehydroepiandrosterone sulfate levels and serum vitamin D deficiency. Protein-protein interaction (PPI) network analysis revealed a high degree of connectivity between these 187 proteins.

New Roles for Vitamin D Superagonists: From COVID to Cancer

Vitamin D is a potent steroid hormone that induces widespread changes in gene expression and controls key biological pathways. Here we review pathophysiology of vitamin D with particular reference to COVID-19 and pancreatic cancer. Utility as a therapeutic agent is limited by hypercalcemic effects and attempts to circumvent this problem have used vitamin D superagonists, with increased efficacy and reduced calcemic effect. A further caveat is that vitamin D mediates multiple diverse effects. Some of these (anti-fibrosis) are likely beneficial in patients with COVID-19 and pancreatic cancer, whereas others (reduced immunity), may be beneficial through attenuation of the cytokine storm in patients with advanced COVID-19, but detrimental in pancreatic cancer. Vitamin D superagonists represent an untapped resource for development of effective therapeutic agents. However, to be successful this approach will require agonists with high cell-tissue specificity.

Vitamin D regulates prostate cell metabolism via genomic and non-genomic mitochondrial redox-dependent mechanisms

Vitamin D deficiency has been associated with increased risk for aggressive prostate cancer (PCa). Prostate epithelium has a unique metabolism compared to other tissues. Normal prostate exhibits low levels of mitochondrial respiration and there is a metabolic switch to increased oxidative phosphorylation in PCa. 25-hydroxyvitamin D (25(OH)D) is the major circulating form of vitamin D and is used clinically to determine vitamin D status. Activation of 25(OH)D to the transcriptionally active form, 1,25(OH)₂D occurs via a reduction-oxidation (redox) reaction within the mitochondria that is catalyzed by the P450 enzyme, CYP27B1. We sought to determine if hydroxylation of 25(OH)D by CYP27B1 contributes to non-genomic activity of vitamin D by altering the redox-dependent state of the mitochondria in benign prostate epithelial cells. Exposure to 25(OH)D produced a transient pro-oxidant effect and change in mitochondrial membrane potential that was dependent on CYP27B1. Extended exposure ultimately suppressed mitochondrial respiration, consistent with a protective effect of 25(OH)D in supporting benign prostate metabolism. To model physiologically relevant changes in vitamin D, cells were cultured in constant 25(OH)D then changed to high or deficient concentrations. This model also incurred a biphasic effect with a pro-oxidant shift after short exposure followed by decreased respiration after 16 h. Several genes involved in redox cycling and Mitochondrial Health were regulated by 25(OH)D in these cells. These results indicate a secondary non-genomic mechanism for vitamin D to contribute to prostate cell health by supporting normal mitochondrial respiration.

Racial Differences in Immunological Landscape Modifiers Contributing to Disparity in Prostate Cancer

Prostate cancer affects African Americans disproportionately by exhibiting greater incidence, rapid disease progression, and higher mortality when compared to their Caucasian counterparts. Additionally, standard treatment interventions do not achieve similar outcome in African Americans compared to Caucasian Americans, indicating differences in host factors contributing to racial disparity. African Americans have allelic variants and hyper-expression of genes that often lead to an immunosuppressive tumor microenvironment, possibly contributing to more aggressive tumors and poorer disease and therapeutic outcomes than Caucasians. In this review, we have discussed race-specific differences in external factors impacting internal milieu, which modify immunological topography as well as contribute to disparity in prostate cancer.

Gender Differences in Vitamin D Status in China

Background

Vitamin D insufficiency is widespread in China. Various factors influence vitamin D level in the body. The present study investigated vitamin D status of residents in Jinzhong city, China, and analyzed the influence of gender on vitamin D status.

Material/Methods

In this cross-sectional study, 302 participants (176 men and 126 women) were recruited. Anthropometric data (body circumferences and height, weight) were collected, and serum vitamin D concentration was tested.

Results

Inadequate levels of vitamin D were found in 69% of men and 75% of women. Women’s 25(OH)D level (38.40±12.37 nmol/l) was substantially lower than that of the men (43.49±14.78 nmol/l) (p<0.01). The young women group had the lowest vitamin D level, which was even significantly below that of the elderly women group. Multiple linear regression analysis showed gender was significantly associated with vitamin D status (p<0.01).

Conclusions

Vitamin D deficiency is common in residents of Jinzhong during the winter. Compared to men, women are more prone to have inadequate vitamin D levels.

Cardiorespiratory fitness, different measures of adiposity, and serum vitamin D levels in African-American adults

We examined the associations among cardiorespiratory fitness (CRF), adiposity, and serum 25-hydroxyvitamin D [25(OH)D) levels in African-American (AA) adults. 468 AA patients from the Cooper Clinic in Dallas, TX were examined between 2007 and 2018. Measures included body mass index (BMI), waist circumference (WC), percent body fat (%fat) via skinfolds, CRF via a maximal treadmill test, and 25(OH)D. Participants were classified by CRF based on age and sex, as well as by clinical categories of adiposity exposures and 25(OH)D. We examined trends of 25(OH)D across CRF and adiposity categories. We calculated OR with 95% CIs for 25(OH)D deficiency across categories of CRF and adiposity measures. We observed a significant positive trend for CRF (p=0.01) and a significant inverse trend for BMI (p=0.005) across ordered 25(OH)D categories. Adjusted mean 25(OH)D levels were higher across ordered CRF categories (p=0.03), and lower across ordered categories of BMI (p=0.02), WC (p=0.03) and %fat (p=0.04). When grouped into categories of fit and unfit (upper 80% and lower 20% of the CRF distribution, respectively), OR for vitamin D deficiency was significantly lower in fit compared with unfit men and women (OR=0.55, 95% CI: 0.35–0.87, p=0.01). Compared with normal weight BMI (referent), ORs for 25(OH)D deficiency were significantly higher for BMI-obese subjects (OR=1.70, 95% CI: 1.00–2.87, p=0.04). 25(OH)D levels are positively associated with CRF and negatively associated with different measures of adiposity in AA men and women. Because of the study design, causal inferences cannot be made and future prospective studies are needed.

Association among plasma 1,25(OH)2 D, ratio of 1,25(OH)2 D to 25(OH)D, and prostate cancer aggressiveness

BACKGROUND

African-American (AA) men tend to present with more aggressive prostate cancer (Gleason score >7) than European-American (EA) men. Vitamin D and its metabolites are implicated in prostate cancer biology with vitamin D deficiency, indicated by its metabolite levels in serum or plasma, usually observed in AA men.

OBJECTIVE

To determine if 1, 25-dihydroxy vitamin D3 [1,25(OH)2 D] plasma levels in AA and EA prostate cancer patients alter the risk of having aggressive prostate cancer.

DESIGN

Research subjects from the North Carolina-Louisiana Prostate Cancer Project (AA n = 435 and EA n = 532) were included. Plasma metabolites 1,25(OH)2 D and 25-hydroxyvitamin D3 [25(OH)D] were measured using liquid chromatography with tandem mass spectrophotometry. Research subjects were classified into low (Gleason sum < 7, stage T1-T2, and Prostate-specific antigen (PSA) < 9 ng/mL) or high (Gleason sum > 8 or Gleason sum = 7 with 4 + 3, or PSA > 20 ng/mL, or Gleason sum = 7 and stage T3-T4) aggressive disease.

RESULTS

Research subjects in the second and third tertiles of plasma levels of 1, 25(OH)2 D had lower odds of high aggressive prostate cancer (AA [ORT2vsT1 : 0.66, 95%CI: 0.39-1.12; ORT3vsT1 : 0.83, 95%CI: 0.49-1.41] and EA [ORT2vsT1 : 0.68, 95%CI: 0.41-1.11; ORT3vsT1 : 0.67, 95%CI: 0.40-1.11]) compared with the first tertile, though confidence intervals included the null. Greater 1,25(OH)2 D/25(OH)D molar ratios were associated with lower odds of high aggressive prostate cancer more evidently in AA (ORQ4vsQ1 : 0.45, CI: 0.24-0.82) than in EA (ORQ4vsQ1 : 0.64, CI: 0.35-1.17) research subjects.

CONCLUSIONS

The 1,25(OH)2 D/25(OH)D molar ratio was associated with decreased risk of high aggressive prostate cancer in AA men, and possibly in EA men. Further studies analyzing vitamin D polymorphisms, vitamin D binding protein levels, and prostatic levels of these metabolites may be useful. These studies may provide a better understanding of the vitamin D pathway and its biological role underlying health disparities in prostate cancer.

Physiologic serum 1,25 dihydroxyvitamin D is inversely associated with prostatic Ki67 staining in a diverse sample of radical prostatectomy patients

PURPOSE

To investigate the correlation between serum 25 hydroxyvitamin D, prostatic 25 hydroxyvitamin D, and serum 1,25 dihydroxyvitamin D, and their respective associations with prostatic tumor proliferation at the time of radical prostatectomy.

METHODS

In this cross-sectional analysis of 119 men undergoing radical prostatectomy, serum from whole blood and expressed prostatic fluid was collected on the day of surgery. Tumor proliferation was measured in the dominant tumor on formalin-fixed prostatectomy tissues by immunohistochemical staining for Ki67 and quantified by Aperio imaging analysis.

RESULTS

The sample included 88 African Americans (74%) and 31 (26%) European Americans. Serum and prostatic levels of 25 hydroxyvitamin D were correlated with each other (Spearman's rho (ρ) = 0.27, p = 0.004), and there was also a correlation between serum 25 hydroxyvitamin D and 1,25 dihydroxyvitamin D (ρ = 0.34, p < 0.001). Serum and prostatic 25 hydroxyvitamin D levels were not correlated with Ki67 staining in tumor cells. Serum 1,25 dihydroxyvitamin D was inversely correlated with Ki67 staining in tumor cells (ρ = - 0.30, p = 0.002). On linear regression, serum 1,25 dihydroxyvitamin D was negatively associated with Ki67 staining in tumor cells (β - 0.46, 95% CI - 0.75, - 0.04, p = 0.04).

CONCLUSION

The correlation between physiologic serum levels of 25 hydroxyvitamin D with both prostatic 25 hydroxyvitamin D and serum 1,25 dihydroxyvitamin D suggests that serum levels are reasonable biomarkers of vitamin D status. Furthermore, serum 1,25 dihydroxyvitamin D has an inverse association with Ki67 staining in tumor cells at physiologic levels and may protect against tumor progression.

Novel potential serological prostate cancer biomarkers using CT100+ cancer antigen microarray platform in a multi-cultural South African cohort

There is a growing need for high throughput diagnostic tools for early diagnosis and treatment monitoring of prostate cancer (PCa) in Africa. The role of cancer-testis antigens (CTAs) in PCa in men of African descent is poorly researched. Hence, we aimed to elucidate the role of 123 Tumour Associated Antigens (TAAs) using antigen microarray platform in blood samples (N = 67) from a South African PCa, Benign prostatic hyperplasia (BPH) and disease control (DC) cohort. Linear (fold-over-cutoff) and differential expression quantitation of autoantibody signal intensities were performed. Molecular signatures of candidate PCa antigen biomarkers were identified and analyzed for ethnic group variation. Potential cancer diagnostic and immunotherapeutic inferences were drawn. We identified a total of 41 potential diagnostic/therapeutic antigen biomarkers for PCa. By linear quantitation, four antigens, GAGE1, ROPN1, SPANXA1 and PRKCZ were found to have higher autoantibody titres in PCa serum as compared with BPH where MAGEB1 and PRKCZ were highly expressed. Also, p53 S15A and p53 S46A were found highly expressed in the disease control group. Statistical analysis by differential expression revealed twenty-four antigens as upregulated in PCa samples, while 11 were downregulated in comparison to BPH and DC (FDR = 0.01). FGFR2, COL6A1and CALM1 were verifiable biomarkers of PCa analysis using urinary shotgun proteomics. Functional pathway annotation of identified biomarkers revealed similar enrichment both at genomic and proteomic level and ethnic variations were observed. Cancer antigen arrays are emerging useful in potential diagnostic and immunotherapeutic antigen biomarker discovery.

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.

Prostatic compensation of the vitamin D axis in African American men

BACKGROUND. African American (AA) men are disproportionately affected by both prostate cancer (PCa) and vitamin D deficiency compared with European American (EA) men. Vitamin D deficiency is linked to increased PCa aggressiveness and mortality. Therefore, it has been hypothesized that vitamin D deficiency may contribute to the PCa disparity between AA and EA men. METHODS. We studied a cross sectional group of 60 PCa patients (AA, n = 31; EA, n = 29) who underwent radical prostatectomy. Vitamin D metabolites 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)₂D) were measured in the serum and tissue by uHPLC-MS-MS. Tissue was laser capture microdissected, and gene expression was quantified by microarray. DNA isolated from whole blood was genotyped for West African ancestry markers and vitamin D-related SNPs. RESULTS. Serum concentrations of 25(OH)D were lower in AAs, but concentrations of 1,25(OH)₂D in the prostate tissue were higher compared with EAs. Expression of the vitamin D receptor was higher in prostate tissue from AAs. Expression of the extracellular receptor of vitamin D binding protein, LRP2, was positively associated with West African ancestry and inversely associated with tissue 25(OH)D concentrations in AAs. CONCLUSIONS. The relationships between vitamin D binding protein LRP2 and vitamin D metabolites suggest that the prohormone is actively transported into the prostate, followed by intraprostatic conversion to the active hormone, rather than passive diffusion. These findings support the presence of a compensatory response in prostate tissue to vitamin D deficiency in AAs and reveal a previously unknown complexity involving tissue distribution of vitamin D metabolites. FUNDING. Department of Defense Prostate Cancer Research Program Idea Award for Disparities Research PC121923 (LN and RK) and the NIH 1R01MD007105 (RK).

Association between Serum 25-Hydroxy-Vitamin D and Aggressive Prostate Cancer in African American Men

African American men have higher incidence rates of aggressive prostate cancer, where high levels of calcium and serum vitamin D deficient levels play a role in the racial differences in incidence. In this study, we examined associations of serum vitamin D with aggressive prostate cancer to improve our understanding of higher susceptibility of aggressive disease in this racial cohort. From Howard University Hospital, 155 African American men with clinically-identified prostate cancer were identified; 46 aggressive cases, and 58 non-aggressive cases. Serum vitamin D was assessed from fasting blood samples, and total calcium intake was assessed using the Block Food Frequency Questionnaire. Vitamin D receptor polymorphisms from three different loci were genotyped; rs731236, rs1544410, and rs11568820. Multivariate logistic regression models were used to determine odds ratios (OR) and 95% confidence intervals (CI) comparing aggressive to non-aggressive prostate cancer. Vitamin D deficiency (<20 ng/mL) significantly increased risk of aggressive disease (OR: 3.1, 95% CI: 1.03–9.57, p-value = 0.04). Stratification by total calcium showed high calcium levels (≥800 mg/day) modified this association (OR: 7.3, 95% CI: 2.15–47.68, p-interaction = 0.03). Genetic variant rs11568820 appeared to increase the magnitude of association between deficient serum vitamin D and aggressive prostate cancer (OR: 3.64, 95% CI: 1.12–11.75, p-value = 0.05). These findings suggest that high incidence of aggressive prostate cancer risk in African American men may be due in-part to deficient levels of serum vitamin D. Other factors, including genetics, should be considered for future studies.

Systems analysis of the prostate transcriptome in African-American men compared with European-American men

AIM

African-Americans (AA) have increased prostate cancer risk and a greater mortality rate than European-Americans (EA). AA exhibit a high prevalence of vitamin D deficiency. We examined the global prostate transcriptome in AA and EA, and the effect of vitamin D₃ supplementation.

PATIENTS & METHODS

Twenty-seven male subjects (ten AA and 17 EA), slated to undergo prostatectomy were enrolled in the study. Fourteen subjects received vitamin D₃ (4000 IU daily) and 13 subjects received placebo for 2 months prior to surgery.

RESULTS

AA show higher expression of genes associated with immune response and inflammation.

CONCLUSION

Systems level analyses support the concept that Inflammatory processes may contribute to disease progression in AA. These transcripts can be modulated by a short course of vitamin D₃ supplementation.

Vitamin D and Immune Response: Implications for Prostate Cancer in African Americans

Prostate cancer (PCa) is the most common cancer among men in the U.S. African American (AA) men have a higher incidence and mortality rate compared to European American (EA) men, but the cause of PCa disparities is still unclear. Epidemiologic studies have shown that vitamin D deficiency is associated with advanced stage and higher tumor grade and mortality, while its association with overall PCa risk is inconsistent. Vitamin D deficiency is also more common in AAs than EAs, and the difference in serum vitamin D levels may help explain the PCa disparities. However, the role of vitamin D in aggressive PCa in AAs is not well explored. Studies demonstrated that the active form of vitamin D, 1,25-dihydroxyvitamin D, has anti-inflammatory effects by mediating immune-related gene expression in prostate tissue. Inflammation also plays an important role in PCa pathogenesis and progression, and expression of immune-related genes in PCa tissues differs significantly between AAs and EAs. Unfortunately, the evidence linking vitamin D and immune response in relation to PCa is still scarce. This relationship should be further explored at a genomic level in AA populations that are at high risk for vitamin D deficiency and fatal PCa.

Vitamin D status: ready for guiding prostate cancer diagnosis and treatment?

Vitamin D deficiency is associated with increased risk of prostate cancer for those with elevated prostate-specific antigen (PSA) level or abnormal digital rectal examination. Vitamin D deficiency is also associated with aggressive prostate cancer. Vitamin D level could be added as an additional factor to consider before ordering a biopsy. Clin Cancer Res; 20(9); 2241-3. ©2014 AACR.

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.

Null association between vitamin D and PSA levels among black men in a vitamin D supplementation trial

BACKGROUND

Black men exhibit a high prevalence of vitamin D deficiency as well as a higher incidence of prostate cancer and higher mortality rates from prostate cancer than Whites. There are few data about the effect of vitamin D3 (cholecalciferol) supplementation on prostate-specific antigen (PSA) in healthy Black men.

METHODS

During three winters from 2007 to 2010, 105 Black men (median age, 48.9 years) of Boston, MA were randomized into a four-arm, double-blind trial for 3 months of placebo, 1,000, 2,000, or 4,000 U of vitamin D3. At baseline and 3 months, free and total PSA was measured.

RESULTS

With vitamin D supplementation, no significant differences in free and total PSA were observed; free PSA, -0.0004 ng/mL (P = 0.94) and total PSA, -0.004 ng/mL (P = 0.92) for each additional 1,000 U/d of vitamin D3.

CONCLUSION

Within an unselected population of healthy Black men without a cancer diagnosis, we found no effect of vitamin D supplementation on free or total PSA.

IMPACT

These findings support prior findings of no change in PSA with vitamin D supplementation and emphasize the need for new methods to assess the influence of vitamin D supplementation on prostate cancer prevention.

In older men, lower plasma 25-hydroxyvitamin D is associated with reduced incidence of prostate, but not colorectal or lung cancer

CONTEXT AND OBJECTIVE

Prostate, colorectal and lung cancers are common in men. In this study, we aimed to determine whether vitamin D status is associated with the incidence of these cancers in older men.

DESIGN

Prospective cohort study.

SETTING AND PARTICIPANTS

4208 older men aged 70-88 years in Perth, Western Australia.

MAIN OUTCOME MEASURES

Plasma 25-hydroxyvitamin D [25(OH)D] concentration was measured by immunoassay. New diagnoses of prostate, colorectal and lung cancers were determined via electronic record linkage.

RESULTS

During a mean follow-up of 6.7±1.8 years, there were 315, 117 and 101 new diagnoses of prostate, colorectal and lung cancer. In multivariate competing risks proportional hazards models, every 10 nmol/l decrease in 25(OH)D concentration was associated with a 4% reduction in prostate cancer incidence (sub-hazard ratio [SHR] 0.96, 95% confidence interval [CI] 0.92-1.00). Every halving of 25(OH)D concentration was associated with a 21% reduction in incident prostate cancer in multivariate analysis (SHR 0.79, 95% CI 0.63-0.99). Following exclusion of prostate cancer cases diagnosed within 3 years of blood sampling, low 25(OH)D <50 nmol/l was associated with lower incident prostate cancer, and higher 25(OH)D >75 nmol/l was associated with higher incidence, when compared to the reference range 50-75 nmol/l, respectively (p = 0.027). Significant associations were also observed when 25(OH)D was modeled as a quantitative variable. No associations were observed between plasma 25(OH)D concentration with incidence of colorectal or lung cancer.

CONCLUSION

Lower levels of vitamin D may reduce prostate cancer risk in older men. By contrast, levels of vitamin D did not predict incidence of colorectal or lung cancers. Further studies are needed to determine whether a causal relationship exists between vitamin D and prostate cancer in ageing men.