Effect of Vitamin D Supplementation in Prostate Cancer: A Systematic Review of Randomized Control Trials

Obesity and main urologic cancers: Current systematic evidence, novel biological mechanisms, perspectives and challenges

Urologic cancers (UC) account for 13.1% of all new cancer cases and 7.9% of all cancer-related deaths. A growing body of evidence has indicated a potential causal link between obesity and UC. The aim of the present review is to appraise in a critical and integrative manner evidence from meta-analyses and mechanistic studies on the role of obesity in four prevalent UC (kidney-KC, prostate-PC, urinary bladder-UBC, and testicular cancer-TC). Special emphasis is given on Mendelian Randomization Studies (MRS) corroborating a genetic causal association between obesity and UC, as well as on the role of classical and novel adipocytokines. Furthermore, the molecular pathways that link obesity to the development and progression of these cancers are reviewed. Available evidence indicates that obesity confers increased risk for KC, UBC, and advanced PC (20-82%, 10-19%, and 6-14%, respectively), whereas for TC adult height (5-cm increase) may increase the risk by 13%. Obese females tend to be more susceptible to UBC and KC than obese males. MRS have shown that a higher genetic-predicted BMI may be causally linked to KC and UBC but not PC and TC. Biological mechanisms that are involved in the association between excess body weight and UC include the Insulin-like Growth Factor axis, altered availability of sex hormones, chronic inflammation and oxidative stress, abnormal secretion of adipocytokines, ectopic fat deposition, dysbiosis of the gastrointestinal and urinary tract microbiomes and circadian rhythm dysregulation. Anti-hyperglycemic and non-steroidal anti-inflammatory drugs, statins, and adipokine receptor agonists/antagonists show potential as adjuvant cancer therapies. Identifying obesity as a modifiable risk factor for UC may have significant public health implications, allowing clinicians to tailor individualized prevention strategies for patients with excess body weight.

The Multiple Effects of Vitamin D against Chronic Diseases: From Reduction of Lipid Peroxidation to Updated Evidence from Clinical Studies

Background: Vitamin D exerts multiple beneficial effects in humans, including neuronal, immune, and bone homeostasis and the regulation of cardiovascular functions. Recent studies correlate vitamin D with cancer cell growth and survival, but meta-analyses on this topic are often not consistent. Methods: A systematic search of the PubMed database and the Clinical Trial Register was performed to identify all potentially relevant English-language scientific papers containing original research articles on the effects of vitamin D on human health. Results: In this review, we analyzed the antioxidant and anti-inflammatory effects of vitamin D against acute and chronic diseases, focusing particularly on cancer, immune-related diseases, cardiomyophaties (including heart failure, cardiac arrhythmias, and atherosclerosis) and infectious diseases. Conclusions: Vitamin D significantly reduces the pro-oxidant systemic and tissue biomarkers involved in the development, progression, and recurrence of chronic cardiometabolic disease and cancer. The overall picture of this review provides the basis for new randomized controlled trials of oral vitamin D supplementation in patients with cancer and infectious, neurodegenerative, and cardiovascular diseases aimed at reducing risk factors for disease recurrence and improving quality of life.

A Longitudinal Study of the Relationship between Shift Work and Prostate-Specific Antigen in Healthy Male Workers

As shift work has become prevalent globally, it is important to evaluate the health effects of shift work on employees. Several studies have demonstrated a positive association between shift work and prostate cancer. Therefore, we aimed to further examine the relationship between shift work and elevated prostate-specific antigen (PSA). Our study collected data from 66,817 male participants at baseline and followed up for about 6 years. We categorized shift worker status and shift schedule types. To evaluate the risk of elevated PSA on shift workers, we estimated hazard ratios using the Cox proportional hazards regression analyses. During a median follow-up of 4.1 years, 1030 participants developed elevated PSA. The multivariable-adjusted hazard ratio (HR) of elevated PSA for shift workers compared with daytime workers was 1.37 (1.04-1.80). Among shift workers, rotating shift workers (HR = 1.47, 95% CI 1.06-2.03) showed a significantly increased risk of elevated PSA compared with daytime workers. Our longitudinal study provides evidence for an association between shift work, especially rotating shift work, and elevations of PSA.

Vitamin D3 attenuates doxorubicin-induced senescence of human aortic endothelial cells by upregulation of IL-10 via the pAMPKα/Sirt1/Foxo3a signaling pathway

The toxicity of doxorubicin to the cardiovascular system often limits its benefits and widespread use as chemotherapy. The mechanisms involved in doxorubicin-induced cardiovascular damage and possible protective interventions are not well-explored. Using human aortic endothelial cells, we show vitamin D3 strongly attenuates doxorubicin-induced senescence and cell cycle arrest. We further show the protective effects of vitamin D3 are mediated by the upregulation of IL-10 and FOXO3a expression through fine modulation of pAMPKα/SIRT1/FOXO3a complex activity. These results have great significance in finding a target for mitigating doxorubicin-induced cardiovascular toxicity.

Differential expression of protein disulfide-isomerase A3 isoforms, PDIA3 and PDIA3N, in human prostate cancer cell lines representing different stages of prostate cancer

Prostate cancer (PCa) is a highly heterogeneous and unpredictable progressive disease. Sensitivity of PCa cells to androgens play a central role in tumor aggressiveness but biomarkers with high sensitivity and specificity that follow the progression of the disease has not yet been verified. The vitamin D endocrine system and its receptors, the Vitamin D Receptor (VDR) and the Protein Disulfide-Isomerase A3 (PDIA3), are related to anti-tumoral effects as well as carcinogenesis and have therefore been suggested as potential candidates for the prevention and therapy of several cancer forms, including PCa. In this study, we evaluated the mRNA expression of VDR and PDIA3 involved in vitamin D signaling in cell lines representing different stages of PCa (PNT2, P4E6, LNCaP, DU145 and PC3). This study further aimed to evaluate vitamin D receptors and their isoforms as potential markers for clinical diagnosis of PCa. A novel transcript isoform of PDIA3 (PDIA3N) was identified and found to be expressed in all PCa cell lines analyzed. Androgen-independent cell lines showed a higher mRNA expression ratio between PDIA3N/PDIA3 contrary to androgen-dependent cell lines that showed a lower mRNA expression ratio between PDIA3N/PDIA3. The structure of PDIA3N differed from PDIA3. PDIA3N was found to be a N-truncated isoform of PDIA3 and differences in protein structure suggests an altered protein function i.e. cell location, thioredoxin activity and affinity for 1,25(OH)₂D₃. Collectively, PDIA3 transcript isoforms, the ratio between PDIA3N/PDIA3 and especially PDIA3N, are proposed as candidate markers for future studies with different stages of PCa progression.

Dietary Factors and Supplements Influencing Prostate Specific-Antigen (PSA) Concentrations in Men with Prostate Cancer and Increased Cancer Risk: An Evidence Analysis Review Based on Randomized Controlled Trials

The quest for dietary patterns and supplements efficient in down-regulating prostate-specific antigen (PSA) concentrations among men with prostate cancer (PCa) or increased PCa risk has been long. Several antioxidants, including lycopene, selenium, curcumin, coenzyme Q10, phytoestrogens (including isoflavones and flavonoids), green tea catechins, cernitin, vitamins (C, E, D) and multivitamins, medicinal mushrooms (Ganoderma lucidum), fruit extracts (saw palmetto, cranberries, pomegranate), walnuts and fatty acids, as well as combined supplementations of all, have been examined in randomized controlled trials (RCTs) in humans, on the primary, secondary, and tertiary PCa prevention level. Despite the plethora of trials and the variety of examined interventions, the evidence supporting the efficacy of most dietary factors appears inadequate to recommend their use.

Prostate cancer management: long-term beliefs, epidemic developments in the early twenty-first century and 3PM dimensional solutions

In the early twenty-first century, societies around the world are facing the paradoxal epidemic development of PCa as a non-communicable disease. PCa is the most frequently diagnosed cancer for men in several countries such as the USA. Permanently improving diagnostics and treatments in the PCa management causes an impressive divergence between, on one hand, permanently increasing numbers of diagnosed PCa cases and, on the other hand, stable or even slightly decreasing mortality rates. Still, aspects listed below are waiting for innovate solutions in the context of predictive approaches, targeted prevention and personalisation of medical care (PPPM / 3PM).A.PCa belongs to the cancer types with the highest incidence worldwide. Corresponding economic burden is enormous. Moreover, the costs of treating PCa are currently increasing more quickly than those of any other cancer. Implementing individualised patient profiles and adapted treatment algorithms would make currently too heterogeneous landscape of PCa treatment costs more transparent providing clear "road map" for the cost saving.B.PCa is a systemic multi-factorial disease. Consequently, predictive diagnostics by liquid biopsy analysis is instrumental for the disease prediction, targeted prevention and curative treatments at early stages.C.The incidence of metastasising PCa is rapidly increasing particularly in younger populations. Exemplified by trends observed in the USA, prognosis is that the annual burden will increase by over 40% in 2025. To this end, one of the evident deficits is the reactive character of medical services currently provided to populations. Innovative screening programmes might be useful to identify persons in suboptimal health conditions before the clinical onset of metastasising PCa. Strong predisposition to systemic hypoxic conditions and ischemic lesions (e.g. characteristic for individuals with Flammer syndrome phenotype) and low-grade inflammation might be indicative for specific phenotyping and genotyping in metastasising PCa screening and disease management. Predictive liquid biopsy tests for CTC enumeration and their molecular characterisation are considered to be useful for secondary prevention of metastatic disease in PCa patients.D.Particular rapidly increasing PCa incidence rates are characteristic for adolescents and young adults aged 15-40 years. Patients with early onset prostate cancer pose unique challenges; multi-factorial risks for these trends are proposed. Consequently, multi-level diagnostics including phenotyping and multi-omics are considered to be the most appropriate tool for the risk assessment, prediction and prognosis. Accumulating evidence suggests that early onset prostate cancer is a distinct phenotype from both aetiological and clinical perspectives deserving particular attention from view point of 3P medical approaches.

Role of vitamin D3 in selected malignant neoplasms

Vitamin D₃ is a fat-soluble essential nutrient that affects multiple biologic functions in the organism through calcitriol and the vitamin D₃ receptor. This review article focuses on the results of studies on the relationship between the level of vitamin D₃ and cancer incidence or mortality, but also on the anticancer properties of vitamin D₃ that support its significant role in the prevention, clinical course, and overall survival rates of selected cancers (colorectal, prostate, breast, ovarian, endometrial, bladder, and malignant melanoma). The mechanisms of vitamin D₃ action involve, among others, polymorphism of vitamin D₃ receptor, cell cycle, caspases, and cancer stem cells. The level of vitamin D₃ has been also demonstrated to serve as a biomarker in some cancers, and high levels of vitamin D₃ can be conducive to successful cancer therapy.

Extra-Skeletal Effects of Vitamin D

The vitamin D receptor is expressed in multiple cells of the body (other than osteoblasts), including beta cells and cells involved in immune modulation (such as mononuclear cells, and activated T and B lymphocytes), and most organs in the body including the brain, heart, skin, gonads, prostate, breast, and gut. Consequently, the extra-skeletal impact of vitamin D deficiency has been an active area of research. While epidemiological and case-control studies have often suggested a link between vitamin D deficiency and conditions such as type 1 and type 2 diabetes, connective tissue disorders, inflammatory bowel disorders, chronic hepatitis, food allergies, asthma and respiratory infections, and cancer, interventional studies for the most part have failed to confirm a causative link. This review examines available evidence to date for the extra-skeletal effects of vitamin D deficiency, with a focus on randomized controlled trials and meta-analyses.