Vitamin D Receptor Poly(A) Microsatellite Polymorphism and 25-Hydroxyvitamin D Serum Levels: Association with Susceptibility to Breast Cancer

Association between vitamin D receptor polymorphism and breast cancer in women: An umbrella review of meta-analyses of observational investigations

This study aimed to conduct an umbrella review of meta-analyses to synthesize the existing evidence regarding the relationship between vitamin D receptor (VDR) polymorphism and breast cancer (BC) risk. A comprehensive search was performed across multiple databases, including Embase, PubMed, Scopus, the Cochrane Database of Systematic Reviews, and the Web of Science. The investigation included 17 meta-analyses for the BsmI polymorphism, 6 for the Cdx2 polymorphism, and 6 for the Poly (A) polymorphism. Among the 119 datasets analyzed, only 6 (5 %) reported statistically significant outcomes (p < 0.05), comprising 2 comparisons for VDR BsmI polymorphism (3 %), 1 for VDR Cdx-2 polymorphism (4 %), and 3 for VDR Poly (A) polymorphism (14 %), across various genetic models. Notably, significant heterogeneity was observed in 82 comparisons, and publication bias was detected in 16 comparisons. Furthermore, a substantial proportion (86 %) of the included studies exhibited critically low methodological quality. In conclusion, our findings suggest that VDR polymorphism (BsmI, Cdx-2, and Poly (A)) is not strongly associated with BC risk in the general population.

Unraveling the role of the vitamin D-VDR pathway in pemphigus vulgaris from Tunisian patients

Vitamin D dysregulation has been recognized as a factor that may cause or aggravate autoimmunity. Vitamin D deficiency was found to be common in pemphigus vulgaris (PV) in different populations. This study aimed to investigate the vitamin D-VDR pathway in PV in the Tunisian population. A serological study was carried out to determine the vitamin D status in newly diagnosed PV patients. CYP27B1, CYP24A1 and VDR mRNA expression was assessed using quantitative real-time PCR in peripheral blood mononuclear cells (PBMC) from untreated newly diagnosed and treated PV patients. In addition, a genetic study was accomplished on VDR polymorphisms to investigate the changes in VDR gene expression. Overall, the serological study confirmed the hypovitaminosis D in newly diagnosed PV patients. Vitamin D-VDR pathway gene expression showed downregulation of CYP27B1 and CYP24A1 mRNA in first-discovery patients compared to healthy controls, while VDR mRNA was highly expressed in newly diagnosed PV patients. Moreover, CYP27B1, CYP24A1 and VDR mRNA were significantly upregulated in chronic disease severity groups compared to mild disease groups. The genetic study showed low VDR gene expression in carriers of FokI > CC genotype, which was more frequent among PV patients, and FokI > C-TaqI > C-ApaI > A-polyA > A16 haplotype, suggesting that the VDR gene polymorphisms testing can provide useful information for PV treatment decision-making. In conclusion, our findings underline the impact of vitamin D-VDR pathway disruption in the PV pathophysiology in Tunisian patients.

Significant Association of Poly-A and Fok1 Polymorphic Alleles of the Vitamin D Receptor with Vitamin D Serum Levels and Incidence of Squamous Cutaneous Neoplasia

Vitamin D3, a prohormone, is converted to circulating calcidiol and then to calcitriol, the hormone that binds to the vitamin D receptor (VDR) (a nuclear transcription factor). Polymorphic genetic sequence variants of the VDR are associated with an increased risk of breast cancer and melanoma. However, the relationship between VDR allelic variants and the risk of squamous cell carcinoma and actinic keratosis remains unclear. We examined the associations between two VDR polymorphic sites, Fok1 and Poly-A, and serum calcidiol levels, actinic keratosis lesion incidence, and the history of cutaneous squamous cell carcinoma in 137 serially enrolled patients. By evaluating the Fok1 (F) and (f) alleles and the Poly-A long (L) and short (S) alleles together, a strong association between genotypes FFSS or FfSS and high calcidiol serum levels (50.0 ng/ml) was found; conversely, ffLL patients showed very low calcidiol levels (29.1 ng/ml). Interestingly, the FFSS and FfSS genotypes were also associated with reduced actinic keratosis incidence. For Poly-A, additive modeling showed that Poly-A (L) is a risk allele for squamous cell carcinoma, with an OR of 1.55 per copy of the L allele. We conclude that actinic keratosis and squamous cell carcinoma should be added to the list of squamous neoplasias that are differentially regulated by the VDR Poly-A allele.

Association of vitamin D receptor gene polymorphisms with breast cancer risk

BACKGROUND

Recent literature suggests that vitamin D signaling has a protective effect against breast cancer risk. Thus, the aim of the present study was to find the association of vitamin D receptor (VDR) gene polymorphisms with breast cancer risk.

MATERIALS AND METHODS

Fok1, Bsm1, Apa1, and Taq1 polymorphisms were performed by polymerase chain reaction- restriction fragment length polymorphism (PCR-RFLP) method, and Poly A polymorphism was carried out using PCR-SSCP in 140 breast cancer patients and 155 controls.

RESULTS

Odds ratio was significantly higher in both homozygous variant genotypes (LL) of Poly A polymorphism of VDR (odds ratio [OR] = 5.42, 95% confidence interval [CI] = 1.19-23.31, P = 0.02) and heterozygous variant genotypes (SL) of Poly A polymorphism of VDR (OR = 3.89, 95% CI = 1.10-13.7, P = 0.03). Fok1, Bsm1, Apa1, and Taq1 polymorphisms of VDR gene were not significantly associated with breast cancer risk.

CONCLUSION

Poly A polymorphism at the 3' untranslated region (UTR) of VDR gene was significantly associated with breast cancer risk in West Indian population.

Vitamin D intake, blood vitamin D levels, and the risk of breast cancer: a dose-response meta-analysis of observational studies

Epidemiological studies have indicated that blood vitamin D levels are linked to cancer. Here we conducted a dose-response meta-analysis based on published observational studies to evaluate the association of vitamin D intake and blood vitamin D levels with breast cancer susceptibility. PubMed, EMBASE, and Web of Science databases were searched up to January 2019. The pooled odds ratio (OR) and 95% confidence intervals (CIs) were extracted to estimate the risk. We identified 70 relevant studies on blood vitamin D levels (50 studies) and vitamin D intake (20 studies), respectively. Linear and nonlinear trend analyses were performed and showed that an increase in blood vitamin D levels by 5 nmol/l was associated with a 6% decrease in breast cancer risk (OR = 0.94, 95% CI = 0.93-0.96). Similar results were obtained for premenopausal (OR = 0.96, 95% CI = 0.93-0.99) and postmenopausal women (OR = 0.96, 95% CI = 0.94-0.98). The pooled OR of breast cancer risk for a 400IU/day increase in vitamin D intake was 0.97 (95% CI = 0.92-1.02). In conclusion, we found that breast cancer risk was inversely related to blood vitamin D levels; however, no significant association was observed in vitamin D intake.

Genetic and molecular biology of breast cancer among Iranian patients

Abstract

Background, Breast cancer (BC) is one of the leading causes of cancer related deaths in Iran. This high ratio of mortality had a rising trend during the recent years which is probably associated with late diagnosis.

Main body

Therefore it is critical to define a unique panel of genetic markers for the early detection among our population. In present review we summarized all of the reported significant genetic markers among Iranian BC patients for the first time, which are categorized based on their cellular functions.

Conclusions

This review paves the way of introducing a unique ethnic specific panel of diagnostic markers among Iranian BC patients. Indeed, this review can also clarify the genetic and molecular bases of BC progression among Iranians.

Do genetic polymorphisms of the vitamin D receptor contribute to breast/ovarian cancer? A systematic review and network meta-analysis

BACKGROUND

To identify the most suitable genetic model for detecting the risk of breast cancer (BC)/ovarian cancer (OC) in specific populations.

METHODS

Databases were searched for related studies published up to October 2017. First, VDR genetic polymorphisms were compared in patients with and without cancer. Second, a network meta-analysis was used to reveal the relation between VDR genetic polymorphisms with disease outcomes. Subgroup analyses and a meta-regression were performed according to cancer types, ethnicity and genotypic method. The study is registered in PROSPERO with an ID: CRD42017075505.

RESULTS

Forty-five studies were eligible, which included 65,754 patients and 55 clinical analyses. Of genetic models, results suggested that the recessive model with the CDX2 polymorphism predicted the risk of BC in all cases. The recessive polymorphism model with the rs2228570 (FokI) polymorphism seemed to the best predictor of BC in Caucasian patients, whereas the homozygote model with the CDX2 polymorphism appeared to best predict BC in African-American patients. The homozygote model with the rs2228570 (FokI) polymorphism model appeared to detect the risk of OC in all cases, whereas the heterozygote model with the rs1544410 (BsmI) polymorphism seemed to detect the risk of OC in Caucasian patients.

CONCLUSIONS

By detecting the risk of BC, the recessive model with the rs2228570 (FokI) polymorphism is likely the best genetic model in Caucasian patients, and the homozygote model with the CDX2 polymorphism appears to be best genetic model in African-American patients. Moreover, for detecting clinical risk of OC, heterozygote models with the rs1544410 (BsmI) polymorphism is likely the best genetic model for detecting the risk of OC in Caucasian patients.

Evaluation of Therapeutic Potential of Eugenol-A Natural Derivative of Syzygium aromaticum on Cervical Cancer

Background: The intendment of this study is to determine the pursuance in – vitro anticancer activity and cytotoxicity of Syzygium aromaticum against the human cervical cancer cell line (HeLa) compared to the normal cell lines. Apoptogenic properties of DCM extract of Eugenol was determined in this entire study. Materials and Methods: HeLa cell lines were cultured in DMEM medium and incubated with different concentration of DCM – Eugenol extract. MTT assay brought out the way to determine the cell viability and quantification was done with the optical absorbance at 570 nm and 620 nm as reference. Apoptotic cells were affirmed by dual staining using acridine orange bromide. Besides, the morphology of the nucleus was also confirmed by dual staining. Eugenol inhibited 50% growth (IC50) of HeLa cell lines at 200 mg/ml of extract concentration. Results: Inhibitory efficacy of eugenol isolated from Syzyzgyium aromaticum showed the cell – viability in time and dose dependent manner with consistent morphological changes. Flow cytometer determined the apoptosis confirming the cytotoxicity value for MTT at IC50 with 81.85% cell viability. Dual staining firmly enacts the damaged cells due to AO indicating apoptosis confirmation by dual staining. Morphological analysis also clearly states that nil apoptosis has been seen in control and similarly in eugenol treated when compared to cancerous HeLa cell – line. Conclusion: Evaluation of cytotoxicity effect of eugenol isolated from Syzygium aromaticum showed it can be unrivalled dormant source of prodigious changes in HeLa cell line indicating (revealing) that chemotherapeutic agent.

Vitamin D exposure and Risk of Breast Cancer: a meta-analysis

The relationship between vitamin D and breast cancer is still controversial. The present meta-analysis examines the effects of the 25(OH)D, 1,25(OH)2D and vitamin D intake on breast cancer risk. For this purpose, a PubMed, Scopus and Web of Science-databases search was conducted including all papers published with the keywords “breast cancer” and “vitamin D” with at least one reported relative risk (RR) or odds ratio (OR). In total sixty eight studies published between 1998 and 2018 were analyzed. Information about type of study, hormonal receptors and menopausal status was retrieved. Pooled OR or RR were estimated by weighting individual OR/RR by the inverse of their variance Our study showed a protective effect between 25 (OH) D and breast cancer in both cohort studies (RR = 0.85, 95%CI:0.74–0.98) and case-control studies (OR = 0.65, 95%CI: 0.56–0.76). However, analyzing by menopausal status, the protective vitamin D – breast cancer association persisted only in the premenopausal group (OR = 0.67, 95%CI: 0.49–0.92) when restricting the analysis to nested case-control studies. No significant association was found for vitamin D intake or 1,25(OH)2D. Conclusion: This systematic review suggests a protective relationship between circulating vitamin D (measured as 25(OH) D) and breast cancer development in premenopausal women.

Vitamin D receptor gene polymorphisms and risk of polycystic ovary syndrome in South Indian women

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder of reproductive age women. Emerging evidence suggests that Vitamin D Receptor (VDR) might be a causal factor for characteristics associated with PCOS such as obesity and type 2 diabetes. Present study investigated association between VDR gene BsmI A/G (rs1544410), ApaI A/C (rs7975232) and TaqI T/C (rs731236) single nucleotide polymorphisms and PCOS risk in South Indian women. Genotyping of VDR gene SNPs was carried out in PCOS patients (n = 95) and controls (n = 130) by PCR-RFLP method and confirmed by sequencing analysis. Haplotype frequencies for multiple loci and the standardized disequilibrium coefficient (D') for pairwise linkage disequilibrium (LD) were assessed by Haploview software. Results showed significantly increased frequencies of BsmI G/G (p = .0197), ApaI C/C (p = .048), TaqI C/C (p = .044) genotypes and BsmI G (p = .0181), ApaI C (p = .0092), TaqI C (p = .0066) alleles in patients compared to controls. In addition, the frequency of the 'BsmI G, ApaI C, TaqI C' haplotype was also significantly elevated in patients (p = .0087). In conclusion, the VDR gene BsmI A/G ApaI A/C TaqI T/C and haplotype may constitute an inheritable risk factor for PCOS in South Indian women.

Vitamin D and Breast Cancer: Latest Evidence and Future Steps

Vitamin D (the sunshine vitamin) plays a vital role in calcium homeostasis, skeletal metabolism, and immune, cardiovascular, and reproductive systems’ functions. The worldwide prevalence of vitamin D deficiency is approximately 1 billion. Vitamin D deficiency is a serious health problem with numerous health consequences; it is associated with diabetes, rheumatic arthritis, Parkinson, Alzheimer diseases, osteomalacia, osteoporosis, and fractures in adults and cancers. Many reports showed an inverse association between serum vitamin D concentration and incidence of several cancers, including breast, colorectal, kidney, lung, and pancreatic. About 20 different cancers have incidence rates inversely related to solar UV-B doses and serum vitamin D concentration. Considering the rising incidence of breast cancer and high prevalence of vitamin D deficiency, this review aimed to reflect an association between serum vitamin D concentration and breast cancer risk, reveal the link between vitamin D receptor genetic polymorphisms and breast cancer risk, and review the relationship between vitamin D level, breast cancer risk, and prognostic factors such as tumor stage, grade, size, lymph node involvement, and hormone receptor status.

Association between Vitamin D receptor (Cdx2, Fok1, Bsm1, Apa1, Bgl1, Taq1, and Poly (A)) gene polymorphism and breast cancer: A systematic review and meta-analysis

The purpose of this systemic review and meta-analysis was to examine the relationship between VDR gene polymorphisms and breast cancer. Literature was searched through PubMed database, Google scholar, and the web of knowledge from December 2015 to January 2017 and consists of 34 studies (26,372 cases and 32,883 controls). All statistical measures were done using STATA version 11.2. The heterogeneity among studies was tested using I² statistics. Mantel-Haenszel method and DerSimonian-Laird method were used to combine data from studies using both random-effect model and fixed-effect model, respectively. Potential publication bias was evaluated by Egger's test. Sensitivity analysis was also performed to evaluate the quality and consistency in results. The results of this meta-analysis revealed that VDR gene polymorphisms (Bsm1 bb vs BB; SOR = 1.18, 95% CI = 1.054-1.322, Apa1 aa vs AA; SOR = 1.18, 95% CI = 0.87-1.59, Poly (A) LL vs SS; SOR = 1.41, 95% CI = 1.06-1.88, Fok1 ff + Ff vs FF; SOR = 1.25, 95% CI = 0.896-1.759, Apa1 aa+Aa vs AA; SOR = 1.13, 95% CI = 0.95-1.35, Poly (A) LL + LS vs SS; SOR = 1.19, 95% CI = 1.00-1.43, Poly (A) L vs S; SOR = 1.18, 95% CI = 1.03-1.35) are associated with the breast cancer. Cdx2, Bgl1, and Taq1 do not show association with breast cancer. Thus, the finding of this meta-analysis concluded that VDR Bsm1, Apa1, Fok1, and Poly (A) gene polymorphisms may be susceptible for breast cancer development.

Association between Serum 25-hydroxy Vitamin D Concentration and TaqI Vitamin D Receptor Gene Polymorphism among Jordanian Females with Breast Cancer

BACKGROUND

Breast cancer is the most common type of cancer among females. Genetic polymorphisms might have a role in carcinogenesis. The aim of this study was to determine whether C to T base substitution within TaqI Vitamin D receptor (VDR) gene (rs731236) in exon 9 was a risk factor among patients with breast cancer.

METHODS

Peripheral blood was drawn from 122 Jordanian breast cancer patients and 100 healthy Jordanian volunteers in Al-Basheer Hospital during the summer months (from June to November of 2013, 2014, and 2015). DNA was amplified using polymerase chain reaction (PCR), followed by TaqI restriction enzyme digestion. Quantification of serum 25-hydroxy Vitamin D (25[OH]D) level was determined by competitive immunoassay Elecsys.

RESULTS

Genotypic frequencies for TaqI TT, Tt, and tt genotypes were 41%, 46%, and 13% for breast cancer compared to 42%, 50%, and 8% for control, respectively. Vitamin D serum level was significantly lower in the breast cancer patients (8.1 ± 0.3 ng/ml) compared to the control group (21.2 ± 0.6 ng/ml; P= 0.001). This study showed an inverse association between 25(OH)D serum level and breast cancer risk (odds ratio [OR], 22.72, 95% confidence interval [CI], 10.06-51.29).

CONCLUSIONS

An inverse association was found between 25(OH)D serum level and breast cancer risk. Statistical difference was also found between different VDR TaqI genotypes and circulating levels of 25(OH)D among Jordanian females with breast cancer.

The Correlation of Plasma 25-Hydroxyvitamin D Deficiency With Risk of Breast Neoplasms: A Systematic Review

CONTEXT

Breast cancer has been considered as one of the most common types of cancer among the women worldwide, and patients with breast neoplasms have been reported with high prevalence of low serum 25-hydroxyvitamin D levels.

OBJECTIVES

Our aim was to evaluate the correlation of plasma 25-hydroxyvitamin D deficiency with breast neoplasms risk among women.

DATA SOURCES

PubMed database was searched with MeSH (medical subject headings) keywords "vitamin D AND breast neoplasms" which was restricted by original articles written only in English and published from January 1, 2014.

STUDY SELECTION

To find the articles that met eligibility criteria, titles and abstracts were examined.

DATA EXTRACTION

This systematic review was conducted according to PRISMA (preferred reporting items for systematic reviews and meta-analyses) statement. Critical appraising of evidence was performed, using the study quality assessment tools of national institutes of health, national heart, lung and blood institute (NHLBI).

RESULTS

Overall, 76 potential articles were identified and after screening, 13 articles met eligible criteria for inclusion. Definition of low vitamin D levels varied greatly among studies, making comparisons difficult, but most of them have defined deficiency as 25(OH)D < 20 ng/mL. Evidence was mainly of fair quality.

CONCLUSIONS

This study has provided evidence that vitamin D deficiency has been very prevalent in patients with breast neoplasms, more than comparable matched control population, and risk of breast cancer has increased with low vitamin D levels, suggesting the need for high quality studies that assessed the health consequences attributable to vitamin D deficiency employing standard definitions.