Serum and urinary NGAL but not KIM-1 raises in human postrenal AKI.

BACKGROUND: We examined the value of the novel acute kidney injury (AKI) markers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) in acute postrenal impairment. These biomarkers have been evaluated in prerenal and intrarenal AKI so far, but not in human acute postrenal kidney injury. With regard to multimorbid and critically ill patients the discrimination of different AKI origins often remains a challenge. As the trend goes towards a diagnostic panel of AKI markers, we hereby aim to contribute to evaluate further options of discrimination in an observational case-control study. MATERIALS AND METHODS: Blood and urine samples were obtained from 53 patients with acute obstructive nephropathy secondary to ureteral calculi and 52 age-matched healthy controls. Serum NGAL (sNGAL), urinary NGAL (uNGAL) and urinary KIM-1 (uKIM-1) levels were determined using a commercially available ELISA kit, creatinine applying the Jaffé's method. RESULTS: While urinary levels of KIM-1 were not significantly different between patients with obstructive nephropathy and controls, a striking increase in sNGAL (P < 0·001) and uNGAL (P < 0·01) levels was detected in the obstructive nephropathy group. Within the obstructive nephropathy group, sNGAL (P = 0·01) and uNGAL (P = 0·049) but not uKIM-1 correlated positively with the white blood cell count and uNGAL correlated positively (P = 0·002) with the extent of leucocyturia. CONCLUSIONS: High levels of sNGAL and uNGAL observed in stone-induced acute obstructive nephropathy may represent a valuable marker of postrenal AKI. Low uKIM-1 levels may help to discriminate postrenal AKI events using a panel of markers in this setting.

Vitamin D hydroxylases CYP2R1, CYP27B1 and CYP24A1 in renal cell carcinoma.

BACKGROUND: There is increasing evidence that vitamin D metabolites influence carcinogenesis. Besides its role in mineral homoeostasis, calcitriol, the active metabolite of vitamin D (1,25(OH)2 D3 ), is known to possess antiproliferative, proapoptotic and immunomodulatory effects in cancer. Concerning the synthesis of vitamin D, the hydroxylases CYP2R1, CYP27B1 and CYP24A1 play a critical role, and the latter molecule determines the biological half-life of 1,25(OH)2 D3 , which is synthesized in the proximal renal tubules. MATERIALS AND METHODS: The adjacency of these two biological processes prompted us to investigate the gene expression of CYP2R1, CYP27B1 and CYP24A1 in patients with ccRCC. Using RT-PCR, we retrospectively compared mRNA expression profiles from human ccRCC tumour samples with those derived from the corresponding adjacent healthy tissues (n = 30). RESULTS: We observed that all three genes (CYP2R1, CYP27B1 and CYP24A1) were upregulated in tumours compared with normal tissue (P < 0·0001). Moreover, CYP24A1 displayed a significantly higher expression in tumours than CYP27B1 (P < 0·05) and CYP2R1 (P < 0·0001), whereas no differences in the expression of these genes were found in healthy renal tissue. Gene expression of CYP2R1, CYP27B1 and CYP24A did not differ between pathological classifications (TNM, grading, presence of metastasis). CONCLUSION: We thus conclude that upregulated gene expression of the catabolizing CYP24A1 as well as the synthesizing CYP2R1 and CYP27B1 may lead to a misbalance of vitamin D metabolites in ccRCC and thus contributing to its pathogenesis.

Vitamin D deficiency and a CYP27B1-1260 promoter polymorphism are associated with chronic hepatitis C and poor response to interferon-alfa based therapy.

BACKGROUND & AIMS: Vitamin D is an important immune modulator and preliminary data indicated an association between vitamin D deficiency and sustained virologic response (SVR) rates in hepatitis C virus (HCV) genotype 1 patients. We, therefore, performed a comprehensive analysis on the impact of vitamin D serum levels and of genetic polymorphisms with functional relevance within the vitamin D cascade on chronic hepatitis C and its treatment. METHODS: Vitamin D serum levels, genetic polymorphisms within the vitamin D receptor and 1α-hydroxylase were determined in a cohort of 468 HCV genotype 1, 2, and 3 infected patients who were treated with interferon-alfa based regimens. RESULTS: Chronic hepatitis C was associated with a high incidence of severe vitamin D deficiency compared to controls (25(OH)D(3)<10 ng/ml in 25% versus 12%, p<0.00001). 25(OH)D(3) deficiency correlated with SVR in HCV genotype 2 and 3 patients (50% and 81% SVR for patients with and without severe vitamin D deficiency, respectively, p<0.0001). In addition, the CYP27B1-1260 promoter polymorphism rs10877012 had substantial impact on 1,25-dihydroxyvitamin D serum levels (72, 61, and 60 pmol/ml for rs10877012 AA, AC, and CC, respectively, p=0.04) and on SVR rates in HCV genotype 1, 2, and 3 infected patients (77% and 65% versus 42% for rs10877012 AA, AC, and CC, respectively, p=0.02). CONCLUSIONS: Chronic hepatitis C virus infection is associated with vitamin D deficiency. Reduced 25-hydroxyvitamin D levels and CYP27B1-1260 promoter polymorphism leading to reduced 1,25-dihydroxyvitamin D levels are associated with failure to achieve SVR in HCV genotype 1, 2, and 3 infected patients.

The rs1990760 polymorphism within the IFIH1 locus is not associated with Graves' disease, Hashimoto's thyroiditis and Addison's disease.

BACKGROUND: Three genes have been confirmed as major joint susceptibility genes for endocrine autoimmune disease:human leukocyte antigen class II, cytotoxic T-lymphocyte antigen 4 and protein tyrosine phosphatase non-receptor type 22. Recent studies showed that a genetic variation within the interferon induced helicase domain 1 (IFIH1) locus (rs1990760 polymorphism) is an additional risk factor in type 1 diabetes and Graves' disease (GD). METHODS: The aim of the present study was to investigate the role of the rs1990760 polymorphism within the IFIH1 gene in German patients with GD (n = 258), Hashimoto's thyroiditis (HT, n = 106), Addison's disease (AD, n = 195) and healthy controls (HC, n = 227) as well as in 55 GD families (165 individuals, German) and 100 HT families (300 individuals, Italian). Furthermore, the interaction between rs1990760 polymorphism with human leukocyte antigen (HLA) risk haplotype DQ2(DQA*0501-DQB*0201), the risk haplotypes DQ2/DQ8 (DQA*0301-DQB*0302) and the status of thyroglobulin antibody (TgAb), thyroid peroxidase antibody (TPOAb) and TSH receptor antibody (TRAb) in patients and families were analysed. RESULTS: No significant differences were found between the allele and genotype frequencies for rs1990760 IFIH1 polymorphism in patients with GD, HT, AD and HC. Also no differences were observed when stratifying the IFIH1 rs1990760 polymorphism for gender, presence or absence of thyroid antibodies (GD:TRAb and HT:TPOAb/TgAb) and HLA risk haplotypes (DQ2:for GD and HT, DQ2/DQ8:for AD). Furthermore the transmission analysis in GD and HT families revealed no differences in alleles transmission for rs1990760 IFIH1 from parents with or without HLA risk haplotype DQ2 to the affected offspring. In contrast, by dividing the HT parents according to the presence or absence of thyroid Ab titers, mothers and fathers both positive for TPOAb/TgAb overtransmitted the allele A of IFIH1 rs1990760 to their HT affected offspring (61.8% vs 38.2%;p = 0.05;corrected p [pc] = 0.1). However, these associations did not remain statistically significant after correction of the p-values. CONCLUSION: In conclusion, our data suggest, no contribution from IFIH1 rs1990760 polymorphism to the pathogenesis of either Graves' disease, Hashimoto's thyroiditis or Addison's disease in our study populations. However, in order to exclude a possible influence of the studied polymorphism in specified subgroups within patients with autoimmune thyroid disease, further investigations in larger populations are needed.

Insulin gene polymorphisms in type 1 diabetes, Addison's disease and the polyglandular autoimmune syndrome type II.

BACKGROUND: Polymorphisms within the insulin gene can influence insulin expression in the pancreas and especially in the thymus, where self-antigens are processed, shaping the T cell repertoire into selftolerance, a process that protects from beta-cell autoimmunity. METHODS: We investigated the role of the -2221Msp(C/T) and -23HphI(A/T) polymorphisms within the insulin gene in patients with a monoglandular autoimmune endocrine disease [patients with isolated type 1 diabetes (T1D, n = 317), Addison's disease (AD, n = 107) or Hashimoto's thyroiditis (HT, n = 61)], those with a polyglandular autoimmune syndrome type II (combination of T1D and/or AD with HT or GD, n = 62) as well as in healthy controls (HC, n = 275). RESULTS: T1D patients carried significantly more often the homozygous genotype "CC" -2221Msp(C/T) and "AA" -23HphI(A/T) polymorphisms than the HC (78.5% vs. 66.2%, p = 0.0027 and 75.4% vs. 52.4%, p = 3.7 x 10-8, respectively). The distribution of insulin gene polymorphisms did not show significant differences between patients with AD, HT, or APS-II and HC. CONCLUSION: We demonstrate that the allele "C" of the -2221Msp(C/T) and "A" -23HphI(A/T) insulin gene polymorphisms confer susceptibility to T1D but not to isolated AD, HT or as a part of the APS-II.

CYP2R1-, CYP27B1- and CYP24-mRNA expression in German type 1 diabetes patients.

1,25(OH)(2)D(3) and 25(OH)D(3) have been associated with type 1 diabetes. Diverse enzymes are involved in the synthesis of these metabolites: the 25-Vitamin-D-hydroxylase (CYP2R1), the 25-hydroxyvitamin-D(3)-1-alpha-hydroxylase (CYP27B1) and the 25(OH)D(3)-24-hydroxylase (CYP24) among others. Serum levels of 25(OH)D(3) and 1,25(OH)(2)D(3) were investigated in type 1 diabetes patients (n=173) and the mRNA expression of the CYP2R1, CYP27B1 and CYP24 genes in type 1 diabetes patients (n=33) and healthy controls (n=23). These parameters were correlated with the -1260 (C/A) polymorphism in the CYP27B1 gene. Lower expression of CYP27B1 mRNA in comparison with healthy controls (1.7165 versus 1.7815, P=0.0268) was found. Additionally, patients carrying the genotype CC possessed a reduced amount of CYP27B1 mRNA compared to healthy controls (1.6855 versus 1.8107, respectively, P=0.0220). The heterozygosity rate of the -1260 C/A polymorphism was more frequent in patients with normal levels of 1,25(OH)(2)D(3) (> or =19.9 pmol/ml) than in whose with a level of less than 19.9 pmol/ml (46.7% versus 22.2%, P=0.0134). No correlation with serum levels of 25(OH)D(3) was found. Thus, CYP27B1 gene could play a functional role in the pathogenesis of type 1 diabetes through modulation of its mRNA expression and influence serum levels of 1,25(OH)(2)D(3) via the -1260 C/A polymorphism.

HLA-DQ haplotypes in Spanish and German families with Graves' disease: contribution to DQA1*0501-DQB1*0301 mediated genetic susceptibility from fathers.

Genetic and environmental factors are involved in the pathogenesis of Graves' disease. The human leukocyte antigen (HLA) locus is considered to be one risk factor for Graves' disease but parent of origin effects have not been studied. Therefore, we investigated the transmission of HLA risk haplotypes DQA1*0501, DQA1*0501-DQB1*0201 (DQ2), and DQA1*0501-DQB1*0301 (DQ7) in two Graves' disease family-cohorts from Spain and Germany. Altogether 208 trio-families (109 from Spain and 99 from Germany; n = 624 individuals) with Graves' disease were genotyped for HLA-DQ alleles DQA1*0501 and the haplotypes DQA1*0501-DQB1*0201 (DQ2) and DQA1*0501-DQB1*0301 (DQ7). Since both family groups-German and Spanish-showed the same pattern of HLA transmission and nontransmission, they were analyzed together. HLA DQA1*0501 and DQA1*0501-DQB1*0201 (DQ2) were significantly overtransmitted from the parents to the affected offspring (204 vs. 131, p = 0.0057, pc = 0.0228 and 109 vs. 55, p = 0.0036, pc = 0.0144, respectively). These haplotypes were preferentially transmitted from fathers and DQA1*0501-DQB1*0301 (DQ7) was also more prevalent in fathers (24.0% vs. 17.1%, p = 0.0162, pc = 0.0648). We conclude, that HLA DQA1*0501 and DQA1*0501-DQB1*0201 (DQ2) are strongly associated with Graves' disease in both populations. A parent of origin effect of risk haplotypes can not be excluded at present, warranting further family studies.

Protection from type 1 diabetes by vitamin D receptor haplotypes.

Vitamin D has been involved in the modulation of calcium and bone metabolism as well as in the immune system, where it suppresses the proliferation of activated T cells. These effects are exerted via the vitamin D receptor (VDR). Polymorphisms within this gene have been exhaustively studied in diverse autoimmune diseases but with inconsistent results. We previously reported a positive association of polymorphisms within the VDR gene (Apa I, Taq I, Bsm I, and Fok I). In the present article we extended our previous reports to seven additional polymorphisms (rs757343, rs9729, rs2853559, rs1989969, rs3847987, rs2238135, and rs4516035) in a larger set of German simplex type 1 diabetes families. Additionally we correlated serum levels of 25(OH)D(3) and 1,25(OH)(2)D(3) with VDR genotypes and haplotypes. The haplotypes "CG" (Taq I-Apa I), "CGG" (Taq I-Apa I-Tru I), "CGC" (Taq I-Apa I-Fok I), "GCTG" (rs9729-Taq I-Apa I-Tru I), and "CGGC"(Taq I-Apa I, Tru I, Fok I) were less often transmitted, thus negatively associated with type 1 diabetes. Patients who carried the genotype "CC" of the rs3847987 polymorphism had higher median serum levels of 25(OH)D(3). Furthermore, the majority of patients with this genotype possessed normal serum levels of 25(OH)D(3). We conclude that variants of the VDR may confer a genetic protection from type 1 diabetes. Furthermore, normal serum levels of 25(OH)D(3) appear to correlate with a VDR genotype. This supports a role of vitamin D in the immune pathogenesis of type 1 diabetes.

[Her2-Neu expression in ductal adenocarcinomas of the breast gland: correlation with histopathological parameters and estrogen receptors' expression in Mexican patients]. / Expresión del Her2-Neu en el adenocarcinoma ductal de la glándula mamaria: correlación con parámetros histopatológicos y expresión de receptores estrogénicos en pacientes mexicanas.

BACKGROUND: Breast cancer is a general health problem that annually produces 400,000 deaths worldwide. Its early diagnosis leads to high cure rates; nevertheless, in Mexico City this happens rarely. Her2-Neu is an oncogene that is expressed on breast cancer cells, with aggressive behaviour and metastasis. In the United States 20 to 30% of the patients present an over-expression of this protein. This phenomenon has been used as a prognostic parameter and as a predictive and indication factor for therapy with monoclonal antibodies directed against this protein and for therapy with taxanes. OBJECTIVE: To know the biology and distribution of Her2-Neu expression in Mexican breast cancer patients in order to evaluate its potential as a prognostic and predictive factor in the treatment of the breast cancer. PATIENTS AND METHOD: In the cases of invasive ductal adenocarcinomas of the breast we compared by immunohistochemistry the Her2-Neu and estrogen receptor expressions with the histopathological characteristics. The results were evaluated statistically. RESULTS: We found 122 cases of breast adenocarcinoma, from which we evaluated 108 for fulfilling the selection criteria of invasive ductal adenocarcinoma. Patient's mean age was 51.8 +/- 13.2 years. The mean tumour diameter was 3.5 +/- 2.0 cm and the mean number of lymph nodes with metastasis was 6.8. The Her2-Neu (score 2+ and 3+) expression was found in 36.1% of the patients. The tumour diameter and the presence of metastatic disease had strong relation with the Her2-Neu expression level. We did not find correlation with the differentiation level, the patient's age and the presence or absence of oestrogen receptors. CONCLUSIONS: Since the percentage of patients with Her2-Neu expression is high (36.1%) and there is a close relation between Her2-Neu expression, the tumour size and the presence of lymph node methastasis, the determination of the oncoprotein expression could allow a more detailed prognosis and the treatment with immunotherapy and anthracyclines in order to influence the course of the breast cancer cases.

Sex-specific association of PTPN22 1858T with type 1 diabetes but not with Hashimoto's thyroiditis or Addison's disease in the German population.

BACKGROUND: Endocrine autoimmune disorders share genetic susceptibility loci, causing a disordered T-cell activation and homeostasis (HLA class II genes, CTLA-4). Recent studies showed a genetic variation within the PTPN22 gene to be an additional risk factor. MATERIALS AND METHODS: Patients with type 1 diabetes (n = 220), Hashimoto's thyroiditis (n = 94), Addison's disease (n = 121) and healthy controls (n = 239) were genotyped for the gene polymorphism PTPN22 1858 C/T. RESULTS: Our study confirms a significant association between allelic variation of the PTPN22 1858 C/T polymorphism and type 1 diabetes mellitus (T1D). 1858T was observed more frequently in T1D patients (19.3% vs 11.3%, P = 0.0009; odds ratio for allele T = 1.88, 95% confidence interval [1.3-2.7]). Furthermore, we found a strong association in female patients with T1D (P = 0.0003), whereas there was no significant difference between male patients with type 1 diabetes and male controls. No significant difference was observed between the distribution of PTPN22 C/T in patients with Hashimoto's thyroiditis or Addison's disease and healthy controls. CONCLUSION: The PTPN22 polymorphism 1858 C/T may be involved in the pathogenesis of type 1 diabetes mellitus by a sex-specific mechanism that contributes to susceptibility in females.

Vitamin D receptor polymorphisms are associated with Graves' disease in German and Polish but not in Serbian patients.

Diverse genes are candidates for susceptibility to Graves' disease, including the vitamin D receptor (VDR), which regulates the transcription of target genes in response to the active metabolite 1,25(OH)(2)D(3). We analyzed four polymorphisms of the VDR gene (ApaI, TaqI, BsmI, and FokI) in patients with Graves' disease (n = 789) and healthy controls (n = 823) from three European populations (German, Polish, and Serbian). The VDR ApaI (rs7975232) and TaqI (rs731236) polymorphisms showed no significant difference in any population. The BsmI (rs1544410) variant "b" was associated with Graves' disease in the Polish population (p = 0.0070). The FokI (rs10735810) variant "f " was found to be associated with Graves' disease in Germans and "F" in Polish patients (p = 0.0024 and 0.0049, respectively). Construction of haplotypes for TaqI, ApaI, and BsmI showed the haplotype "Tab" to be the most frequent in the German and Polish population as well as in the Serbian patients, while "tAB" in Serbian controls. Our results show an association of VDR gene polymorphisms in the German and Polish population but not in the Serbian. Furthermore, the VDR polymorphisms are differentially distributed in the three populations. Therefore, VDR polymorphisms analysis needs to be stratified according to the population background.

Immunomodulatory effects of 25-hydroxyvitamin D3 on monocytic cell differentiation and influence of vitamin D3 polymorphisms in type 1 diabetes.

BACKGROUND: Preventive measures and a causal therapy for type 1 diabetes (T1D) remain elusive. An imbalance between different dendritic cells (DC) with increased immunogenic DC and decreased tolerogenic DC (tDC) may lead to T1D. Furthermore, 25(OH)D3 is associated with less adverse effects than 1,25(OH)2D3. PURPOSE: The present study was performed to clarify the remaining issues about the cellular effects of 25(OH)D3 in patients with T1D and the role of genetic polymorphisms of the vitamin D3 (VD3) metabolism on a functional cellular level. MATERIALS AND METHODS: Twelve patients with T1D were case-matched to twelve healthy controls (HC). Monocytes (MC) were either not supplemented or supplemented with 25(OH)D3 in vitro and phenotyped with fluorescence-activated cell sorting. In vitro synthesis and plasma levels of 25(OH)D3 and 1,25(OH)2D3 were analyzed as well as twelve gene polymorphisms of the VD3 metabolism. RESULTS: 25(OH)D3 significantly inhibited differentiation of MC into DC and led to an increase of intermediate cells (IC), which show a similar phenotype as tDC. The patient with a recent onset of T1D showed a higher increase in MC and IC compared to patients with long-standing T1D. There were significant differences for the increase of IC with supplementation of 25(OH)D3 between different genotypes within the polymorphisms of VDR-BsmI-rs1544410, VDR-TaqI-rs731236 and CYP24A1-rs927650. CONCLUSION: This study suggests that 25(OH)D3 shows immunomodulatory effects on a cellular level in patients with T1D and HC by inhibiting the differentiation of MC into DC and promoting the formation of IC, which are similar to tDC, thereby shifting immunity to self-tolerance. The potency of 25(OH)D3 did not differ between patients with T1D and HC. Increased plasma levels of 25(OH)D3 may inhibit a proinflammatory cell milieu. Despite of the limited patient number, this study generates the hypothesis that the immunmodulatory effects may be influenced by genotypes of the VDR and CYP24A1 illustrating their functional role in T1D susceptibility, which is worth further investigation.

Thyroid fetal male microchimerisms in mothers with thyroid disorders: presence of Y-chromosomal immunofluorescence in thyroid-infiltrating lymphocytes is more prevalent in Hashimoto's thyroiditis and Graves' disease than in follicular adenomas.

The presence of fetal cells in a maternal compartment is defined as fetal-maternal microchimerism, which has been detected in thyroids of mothers suffering from autoimmunity. We analyzed the immunohistology of paraffin-embedded thyroid specimen taken at surgery from 49 women with Hashimoto's thyroiditis (n = 25), Graves' disease (n = 15), or nodular or diffuse follicular adenomas (n = 9), whose childbirth history was positive for sons. By fluorescence in situ hybridization we screened for X-chromosome- and Y-chromosome-specific staining and compared the finding with human leukocyte antigen (HLA) DQ types of the mothers and, where available, their offspring. In 23 thyroids we found Y-chromosome-specific staining, which was more frequent in thyroid autoimmune disease (60% Hashimoto's thyroiditis and 40% Graves' disease) than in follicular adenomas (22.2%). There was no significant difference for HLA DQ alleles among women whose thyroids showed Y-chromosome staining and those without. However, a subgroup of all investigated microchimerism-positive mother-child pairs and women with Hashimoto's thyroiditis and Graves' disease more often had the susceptibility alleles HLA DQA1*0501-DQB1*0201 or DQB1*0301. In conclusion, fetal microchimerism is observed in thyroids of mothers with sons, and this is found more frequently in thyroid autoimmune diseases.

FOXE1 association with differentiated thyroid cancer and its progression.

BACKGROUND: Single nucleotide polymorphisms (SNPs) near thyroid transcription factor genes (FOXE1 rs965513/NKX2-1 rs944289) have been shown to be associated with differentiated thyroid cancer (DTC) in Caucasoid populations. We investigated the role of those SNPs in German patients with DTC and also extended our analysis to tumor stages and lymphocytic infiltration of the tumors (ITL). METHODS: Patients with DTC (n=243; papillary, PTC; follicular, FTC) and healthy controls (HC; n=270) were analyzed for the rs965513 and rs944289 SNPs. RESULTS: The case-control analysis for rs965513 SNP showed that the genotypes "AA," "AG," and minor allele "A" were more frequent in patients with DTC than in HC (pronounced in PTC p(genotype)=0.000084, p(allele)=0.006 than FTC p(genotype)=0.29 and p(allele)=0.06). Furthermore, subgroup analysis of the DTC patients stratified for primary tumor stage (T1-T2, T3-T4), the absence or presence of regional lymph node metastases (N0, N1), for distant metastases (M0, M1), as well as for ITL, showed an association of rs965513 with stages T1-T2, T1-T3, N1, and absence of ITL. The NKX2-1 SNP rs944289, however, was not associated with DTC. CONCLUSION: Our results confirm that the FOXE1 rs965513 SNP confers an increased risk for DTC in the German population, particularly allele "A" and the genotypes "AA" and "AG" for PTC. This increased risk was also observed in advanced tumor stages and absence of ITL, which may reflect the course of a more aggressive disease. The NKX2-1 rs944289 SNP, however, appears to play a secondary role in the development of DTC in the German population.

Impaired vitamin D activation and association with CYP24A1 haplotypes in differentiated thyroid carcinoma.

BACKGROUND: Common polymorphisms of the vitamin D receptor gene have been reported to affect the risk of breast, colon, prostate, and differentiated thyroid cancer (DTC), but polymorphisms within the genes of vitamin D metabolizing enzymes have not been studied in DTC. The aim of the present study was to investigate the genes for vitamin D enzymes in patients with DTC and healthy controls (HC) as well as the vitamin D (25-hydroxyvitamin D(3), and 1,25-hydroxyvitamin) status. METHODS: German patients (n=253) with DTC (papillary thyroid carcinoma [PTC] and follicular thyroid carcinoma [FTC]) and HC (n=302) were genotyped for polymorphisms within the vitamin D metabolizing enzymes such as 25-hydroxylase (CYP2R1[rs12794714, rs10741657]), 25-hydroxyvitamin D-1α-hydroxylase (CYP27B1[rs10877012, rs4646536]), and 25-hydroxyvitamin D 24-hydrolase (CYP24A1[rs927650, rs2248137, rs2296241]). Furthermore, the 25-hydroxyvitamin D(3) [25(OH)D(3)] and 1,25-hydroxyvitamin [1,25(OH)(2)D(3)] plasma levels were measured by a radioimmunoassay. RESULTS: There was no difference in the genotypes; however, the CYP24A1 haplotype analysis showed that rs2248137C/rs2296241A (13.1% vs. 19.1%; corrected p [pc]=0.04) was less frequent in the PTC, whereas the haplotypes rs2248137C/rs2296241G (56.0% vs. 41.9%; pc=0.03), rs927650C/rs2296241G (22.5% vs. 8.4%; pc=1.6×10(-3)), and rs927650C/rs2248137C/rs2296241G (21.1% vs. 7.3%; pc=1.5×10(-3)) were more frequent in the FTC compared with HC. Furthermore, if patients and controls were grouped according to four 25(OH)D(3) categories (severely deficient, deficient, insufficient, and sufficient), then the patients with both DTC subtypes had significantly lower levels of circulating 1,25(OH)(2)D(3), especially in the group with a deficient 25(OH)D(3) status compared with the controls. Although the polymorphisms showed no differences stratified for the four 25(OH)D(3) categories, the activation status by 1,25(OH)(2)D(3) differed significantly depending on the genotypes of the investigated CYP24A1 polymorphisms. CONCLUSIONS: A higher risk for DTC is conferred by haplotypes within the CYP24A1 gene, low circulating 25(OH)D(3) levels (deficiency), and a reduced conversion to 1,25(OH)(2)D(3). These results confirm and extend previous observations and also support a role of the vitamin D system in the pathogenesis of DTC. How deficient 25(OH)D(3) levels in combination with certain CYP24A1 haplotypes affect vitamin D activation is the subject of future studies.

Inherited variation in vitamin D genes is associated with predisposition to autoimmune disease type 1 diabetes.

OBJECTIVE: Vitamin D deficiency (25-hydroxyvitamin D [25(OH)D] <50 nmol/L) is commonly reported in both children and adults worldwide, and growing evidence indicates that vitamin D deficiency is associated with many extraskeletal chronic disorders, including the autoimmune diseases type 1 diabetes and multiple sclerosis. RESEARCH DESIGN AND METHODS: We measured 25(OH)D concentrations in 720 case and 2,610 control plasma samples and genotyped single nucleotide polymorphisms from seven vitamin D metabolism genes in 8,517 case, 10,438 control, and 1,933 family samples. We tested genetic variants influencing 25(OH)D metabolism for an association with both circulating 25(OH)D concentrations and disease status. RESULTS: Type 1 diabetic patients have lower circulating levels of 25(OH)D than similarly aged subjects from the British population. Only 4.3 and 18.6% of type 1 diabetic patients reached optimal levels (≥75 nmol/L) of 25(OH)D for bone health in the winter and summer, respectively. We replicated the associations of four vitamin D metabolism genes (GC, DHCR7, CYP2R1, and CYP24A1) with 25(OH)D in control subjects. In addition to the previously reported association between type 1 diabetes and CYP27B1 (P = 1.4 × 10(-4)), we obtained consistent evidence of type 1 diabetes being associated with DHCR7 (P = 1.2 × 10(-3)) and CYP2R1 (P = 3.0 × 10(-3)). CONCLUSIONS: Circulating levels of 25(OH)D in children and adolescents with type 1 diabetes vary seasonally and are under the same genetic control as in the general population but are much lower. Three key 25(OH)D metabolism genes show consistent evidence of association with type 1 diabetes risk, indicating a genetic etiological role for vitamin D deficiency in type 1 diabetes.

The role of cubilin gene polymorphisms and their influence on 25(OH)D3 and 1,25(OH)2D3 plasma levels in type 1 diabetes patients.

BACKGROUND: Megalin and cubilin bind and internalize the 25(OH)D3-DBP complex in the kidney. Once the complex is internalized, 25(OH)D3 is released and activated to 1,25(OH)2D3 the ligand for the vitamin D receptor (VDR). Supporting the important role of cubilin in this process recent findings showed that cubilin deficiency results in decrease of 25(OH)D3 and 1,25(OH)2D3 plasma levels. METHODS: Two hundred T1D patients and healthy controls (n=200) were genotyped for five polymorphisms (rs3740168, rs3740165, rs1801233, rs1801229 and rs2796835) within the cubilin gene. The polymorphisms were analyzed by RFLP or real time PCR. Statistic analyses were performed by using allele-wise and genotype-wise chi2 testing by using BiAS software. A p-value<0.05 was considered as significant. RESULTS: We found that the genotype "AA" of the rs3740165 was more frequent in T1D patients compared to healthy controls (26.7% vs. 5.1%, p=4x10(-7)). Nevertheless no association between the rs3740165 polymorphism and the 25(OH)D3 or 1,25(OH)2D3 plasma levels was found. No association with the other studied polymorphisms was observed. CONCLUSION: Thus our findings reveal a novel association of the cubilin rs3740165 polymorphism with type 1 diabetes. Nevertheless how exactly this polymorphism could increase the risk to develop type 1 diabetes is subject for further investigations.

Polymorphisms of CXCR3-binding chemokines in type 1 diabetes.

Type 1 diabetes (T1D) is a T-cell-mediated autoimmune disease. Although the precise mechanisms leading to the destruction of islet beta cells are unknown, diverse studies support a role of the CXCR3-binding chemokines. A combination of a case (n = 447)-control (n = 300) and family (n = 221) analysis was performed to investigate the role of the CXCL9 (rs10336, rs3733236) and CXCL10 (rs3921, rs35795399 and rs8878) polymorphisms and their interaction with HLA high-risk haplotypes DQ2(DQA*0501-DQB*0201)-DQ8(DQA*0301-DQB*0302) in T1D. In addition, the mRNA expression of these genes and of the CXCR3 in peripheral blood mononuclear cells (PBMCs) of T1D patients was studied. In the family analysis, an overtransmission of the allele T and G of the polymorphisms rs35795399 and rs8878 in the whole group (p = 0.0520 and p = 0.0290, respectively) as well as in combination with the HLA-high risk haplotypes (p = 0.0209 and 0.0340, respectively) were observed. In addition, the haplotype rs8878G-rs35795399T was more often transmitted from parents to affected offspring, whereas the haplotype rs8878A-rs35795399C was less often transmitted (p = 0.0130 and p = 0.0201, respectively). Nevertheless these associations did not remain significant after correction for multiple testing, and they could not be corroborated in the case-control analysis. Although we did not find an association of the CXCL9 and CXCL10 polymorphisms with type 1 diabetes in the German population, we cannot discard their role in other populations or other autoimmune diseases.

Vitamin D receptor polymorphisms in differentiated thyroid carcinoma.

BACKGROUND: Vitamin D receptor (VDR) expression has been shown to be upregulated in several tumors and is supposed to represent an important endogenous response to tumor progression. To investigate the role of the VDR gene and its influence on 25(OH)D(3) and 1,25(OH)(2)D(3) plasma levels in thyroid carcinoma, we analyzed four VDR polymorphisms in patients and healthy controls (HC). METHODS: Patients with thyroid carcinoma (n = 172) (n = 132 for papillary and n = 40 for follicular) and HC (n = 321) were genotyped for the ApaI (rs7975232), TaqI (rs731236), BsmI (rs1544410), and FokI (rs10735810) polymorphisms within the VDR gene and correlated with 25(OH)D(3) and 1,25(OH)(2)D(3) plasma levels. RESULTS: The genotypes AA of the ApaI (rs7975232) and FF of the FokI (rs10735810) polymorphisms were significantly less frequent (12.5% vs. 35.2% and 25% vs. 42.1%, respectively, both corrected p [p(c)] = 0.04) in patients with follicular thyroid cancer (FTC) than in HC. Additionally, the haplotypes, Ta (57.5% vs. 41.4%; p(c) = 0.0207), af (24.6% vs. 14.3%; p(c) = 0.0116), Tab (51.1% vs. 36.8%; p(c) = 0.0495), and Tabf (18.7% vs. 13.6%; p(c) = 0.0240) were more frequent, whereas the haplotypes AF (17.1% vs. 37.2%; p(c) = 0.0008), BF (11.4% vs. 31.9%; p(c) = 0.012), tF (7.9% vs. 25.5%; p(c) = 0.0016), and tABF (7.6% vs. 23%; p(c) = 0.0115) were less frequent in the FTC patients compared to HC. Neither genotype nor haplotype frequencies differed between patients with papillary thyroid cancer (PTC) and HC. Further, individuals with PTC and FTC had a significantly lower level of circulating 1,25(OH)(2)D(3) compared to controls. In contrast, no differences of the 25(OH)D(3) concentration between patients and HC were observed. VDR polymorphisms were not associated with 25(OH)D(3) and 1,25(OH)(2)D(3) plasma levels. CONCLUSIONS: Lower circulating levels of 1,25(OH)(2)D(3) are observed in patients with differentiated thyroid carcinoma. Further, while the alleles AA and FF of the ApaI (rs7975232) and FokI (rs10735810) VDR polymorphisms and the haplotype tABF confer to protection from follicular carcinoma, the haplotype Tabf appeared to be associated with an increased FTC risk. Since this is the first report associating VDR polymorphisms with thyroid carcinoma, these findings need to be confirmed in studies with larger numbers of patients.

TIM-3 polymorphisms in type 1 diabetes families.

TIM-3 is a transmembrane protein preferentially expressed on differentiated Th1 cells, which play a role in Th1-mediated diseases including type 1 diabetes. We investigated the role of the rs10515746 (A/C), rs1036199 (A/C), and rs10053538 (A/C) single nucleotide polymorphisms (SNPs) within the TIM-3 gene in 186 German type 1 diabetes families (558 individuals) and its interaction with human leukocyte antigen (HLA) high-risk haplotypes DQ2(DQA*0501-DQB*0201)-DQ8 (DQA*0301-DQB*0302). Alleles A, C, and A of the rs10515746 (A/C), rs1036199 (A/C), and rs10053538 (A/C) SNPs were found in a frequency of 20.4%, 19.0%, and 4.2%, respectively. Transmission analysis of these polymorphisms did not show any significant difference. Although in patients with HLA DQx/x (neither HLA DQ2 nor DQ8) an undertransmission of allele A (14.3% vs. 85.7%) of the rs10053538 (A/C) SNP and an overtransmission of allele A (66.7% vs. 33.3%) of the rs10515746 (A/C) SNP was observed, these associations did not remain statistically significant after correction for multiple comparisons. Although we found no association of TIM-3 with type 1 diabetes in the German population, we cannot discard a possible association in a larger size.