Group-specific component exon 11 haplotypes (D432E and T436K) and risk of albuminuria in type 2 diabetes mellitus patients.

BACKGROUND: Emerging evidence indicates group-specific component (GC) variants are associated with ethnicity. We aimed to investigate the association of GC variants and protein expression level with T2DM and diabetic nephropathy (DN) in Saudi patients. SUBJECTS AND METHODS: A total of 200 participants (120 T2DM/80 controls) were genotyped for GC-rs7041/GC-rs4588 by real-time polymerase chain reaction. Serum GC was assessed by ELISA and in silico analysis was executed. RESULTS: GC-rs7041 frequency distribution showed no difference between the study groups, while GC-rs4588 showed association with T2DM under all genetic models. rs4588*AA variant was correlated with higher serum GC globulin, albuminuria, and poor glycaemic control. A higher frequency of rs7041*TT and rs4588*AA was evident in macroalbuminuria vs. normoalbuminuria group. Carrying GC-2 haplotype was 2.5 more likely to develop diabetes and correlated with the levels of albuminuria. CONCLUSIONS: GC variants could have independent effects on the risk of T2DM and DN in the study population.

MicroRNA-499a (rs3746444A/G) gene variant and susceptibility to type 2 diabetes-associated end-stage renal disease.

Diabetic nephropathy (DN) is a major risk factor for end-stage renal disease (ESRD). MicroRNAs (miRNAs/miRs) and their variants may be implicated in health and disease, including DN. The present study aimed to investigate the association of the miRNA-499a gene (MIR499A) A/G seed region variant (rs3746444) with DN-associated ESRD susceptibility in patients with diabetes mellitus, and to determine whether there was an association between the different genotypes and the patients' laboratory and clinical data. A case-control pilot study was conducted on 180 adult patients with type 2 diabetes mellitus. A total of 90 patients with ESRD on regular hemodialysis were considered as the cases, and 90 age-, sex- and ethnicity-matched diabetic patients with normo-albuminuria were considered as the controls. MIR499A genotyping was performed using a TaqMan Real-Time allele discrimination assay. Results demonstrated that the MIR499A rs3746444*G variant conferred susceptibility to the development of ESRD under co-dominant [(odds ratio (95% confidence interval): 2.49 (1.41-3.89) and 2.41 (1.61-6.68) for heterozygous and homozygous comparison, respectively], dominant [2.30 (1.18-3.90)] and allelic [1.82 (1.17-2.83)] models. Different genotypes of the specified variant did not exhibit significant associations with the clinic-laboratory data of the studied patients or the circulating miR-499a plasma levels. In conclusion, results of the present study suggested that MIR499A rs3746444 may be a susceptibility variant for DN-associated ESRD in the study population. However, larger sample size studies with different ethnicities are warranted to verify these findings.

Molecular analysis of homeostatic iron regulator, transmembrane protease serine-6, and BTB domain-containing protein-9 variants and iron parameters in blood donors.

Genetic variants associated with iron homeostasis have been identified, but their association with iron-related indices and variables among different ethnic populations remains controversial. We aimed to explore the genotype frequency and allelic distribution of three iron-metabolism related variants in homeostatic iron regulator gene (HFE; rs1800562 G/A), transmembrane protease, Serine-6 gene (TMPRSS6; rs855791 A/G), and BTB domain-containing protein-9 gene (BTBD9; rs9357271 C/T) among a sample of the Middle Eastern blood donors and to detect the association of these variants on blood indices, and serum hepcidin/ferritin levels. Real-Time TaqMan genotyping assay for the specified variants was applied for 197 unrelated blood donors. Complete blood picture and serum hepcidin/ferritin levels were assessed. All participants were carriers of rs1800562*G/G genotype for HFE. The frequency of A/A and A/G genotypes of TMPRSS6 rs855791 variant was 55% and 45%, and for C/C, C/T, and T/T of BTBD9 rs9357271, were 15%, 43%, and 42%, respectively. Minor allele frequencies of rs855791*G and rs9357271*C were 0.23 and 0.37. The GGC genotype combination (for HFE/TMPRSS6/BTBD9, respectively) was more frequent in male participants. Higher serum hepcidin and hepcidin/ferritin ratio were observed in TMPRSS6 (A/G) carriers. While subjects with BTBD9 C/T and TT genotypes had lower serum ferritin values and higher levels of hepcidin and hepcidin/ferritin ratio compared with C/C genotype. No significant associations were found with any other blood parameters. In conclusion, TMPRSS6 rs855791 (A/G) and BTBD9 rs9357271 (C/T) variants were prevalent in the present blood donor population and may influence the serum hepcidin and/or ferritin levels.

Prognostic value of BRAF/MIR-17 signature and B-Raf protein expression in patients with colorectal cancer: A pilot study.

BACKGROUND: Despite the recent improvement in colorectal cancer (CRC) treatment, it still has a poor prognosis with a low survival rate. Genetic and epigenetic mechanisms have proved to play a substantial role in CRC tumorigenesis and progression. According to Gene Ontology and TargetScan analyses, the B-Raf proto-oncogene (BRAF) gene is one of the microRNA-17 (miR-17) targets. We aimed to explore the prognostic value of B-Raf protein and BRAF/microRNA-17 (MIR-17) gene expression signature in CRC archived samples. METHODS: B-Raf protein expression was identified by immunohistochemistry, while gene expression studies were quantified by real-time qPCR in 53 paired archived CRC specimens. RESULTS: The BRAF showed higher expressions in CRC specimens relative to non-cancer tissues (p = 0.006). MIR17 expression was inversely and significantly correlated with both B-Raf protein (r = -0.79, p < 0.001) and gene expression (r = -0.35, p = 0.010) and showed a significant direct correlation with a high rate of relapse (p = 0.020). BRAF/miR-17 expression in CRC was associated inversely with tumor size, high grade of colonic carcinoma, lymph node metastasis, and carcinoma subtype. Spearman correlation and Kaplan-Meier survival curve analyses revealed that disease-free survival and overall survival were inversely and significantly correlated with positive B-Raf protein expression (r = -0.31 and -0.35, p = 0.023 and 0.011, respectively) and directly correlated with log BRAF/MIR17 ratio (r = 0.50 and 0.41, p < 0.001 and = 0.003, respectively). Cox hazard regression analysis revealed the BRAF/MIR17 ratio could predict both types of patients' survival, among other variables. CONCLUSION: BRAF/MIR17 ratio could have prognostic utility in patients with CRC. Further larger-scale studies are warranted to confirm this utility.

Analysis of microRNA processing machinery gene (DROSHA, DICER1, RAN, and XPO5) variants association with end-stage renal disease.

BACKGROUND: MicroRNA (miRNA) processing machinery gene variant was associated with several diseases. We aimed to explore for the first time the association of machinery gene (DROSHA rs10719A/G; DICER1 rs3742330A/G; RAN rs14035C/T; and XPO5 rs11077T/G) variants with the susceptibility and phenotype of end-stage renal disease (ESRD). METHOD: A total of 281 participants (98 ESRD patients and 183 healthy volunteers) were enrolled. Real-Time TaqMan allelic discrimination assay was applied for the genotyping of the specified variants. Multiple logistic regression models, univariate, multivariate, and principal component analyses were carried out. RESULTS: Carrying one DICER1 rs3742330*G allele conferred protection against developing ESRD [heterozygote comparison: OR = 0.30, 95% CI = 0.15-0.62, dominant model: OR = 0.35, 95% CI = 0.17-0.70]. Similarly, for XPO5 rs11077T/G, homozygote and heterozygote carriers of G variant were less likely to develop ESRD [homozygote comparison: adjusted OR = 0.23, 95% CI = 0.11-0.50, and heterozygote comparison: OR = 0.50, 95% CI = 0.22-0.92, and allelic model: OR = 0.46, 95% CI = 0.34-0.70]. RAN rs14035*TT subjects were 5 times more likely to develop ESRD while being heterozygote (CT) have twice the risk [homozygote comparison: 5.18, 95% CI = 2.28-11.8, heterozygote comparison: OR = 2.12, 95% CI = 1.10-409]. Subgroup analysis also detected DICER1 rs3742330*A, XPO5 rs11077*T, and RAN rs14035*T as genetic risk determinants for ESRD development in both sex and age categories. Two genotype combinations of DROSHA/DICER1/XPO5/RAN were associated with increased susceptibility to ESRD [A-A-T-T: OR = 9.49, 95%CI = 2.48-36.31 (P = .001) and G-A-T-T: OR = 5.92, 95%CI = 1.77-19.83 (P = .004), respectively]. CONCLUSION: Variants and combined genotypes of DICER1 rs3742330, XPO5 rs11077, and RAN rs14035 might be associated with ESRD development in the study population. Integrating molecular analysis in ESRD risk stratification is warranted.

Long non-coding RNA MALAT1 and microRNA-499a expression profiles in diabetic ESRD patients undergoing dialysis: a preliminary cross-sectional analysis.

Background: Circulating non-coding RNAs (ncRNAs) have been implicated in health and disease. This study aimed to evaluate the serum expression profile of microRNA-499a (miR-499a) and its selected bioinformatically predicted partner long-ncRNA MALAT1 (metastasis-associated lung adenocarcinoma transcript 1) in diabetes-related end-stage renal disease (ESRD) patients and to correlate the expressions with the patients' clinicolaboratory data.Subjects and methods: Real-time quantitative polymerase chain reaction was applied in diabetics with and without ESRD (n = 90 for each).Results: Serum MALAT1 expression levels were increased in the ESRD group relative to diabetics without ESRD with median (quartile) values of 10.5 (1.41-126.7) (p < .001). However, miR-499a levels were decreased in more than half of ESRD patients with a median of 0.96 (0.13-3.14). Both MALAT1 and miR-499a expression levels were inversely correlated in the ESRD patient-group.Conclusions: MALAT1 up-regulation and miR-499 down-regulation might be involved in diabetic nephropathy-related ESRD pathogenesis. Functional validation studies are warranted to confirm the MALAT1/miR-499a partnership.

Assessment of Vitamin D-Binding Protein and Early Prediction of Nephropathy in Type 2 Saudi Diabetic Patients.

Early detection of diabetic nephropathy (DN) represents a great challenge in an attempt to reduce the burden of chronic kidney diseases in diabetic patients. This study aimed to investigate the potential early prediction role of urinary vitamin D-binding protein (uVDBP) for the diagnosis of DN and to examine the possible correlation to serum VDBP, high-sensitivity C-reactive protein (hs-CRP), and insulin resistance in these patients. Serum and urine samples were obtained from 40 healthy volunteers and 120 patients with type 2 diabetes divided into 3 groups: normoalbuminuria, microalbuminuria, and macroalbuminuria (urinary albumin excretion rate < 30, 30-300, and >300 µg/mg, resp.); n = 40/group. Serum and urinary VDBP levels were quantified by ELISA. Insulin resistance has been assessed by homeostasis model assessment index (HOMAI). Correction for urine creatinine concentration was applied for urinary quantitative measurements. uVDBP levels were significantly elevated in micro- and macroalbuminuria patient groups compared with those of the normoalbuminuria patient group and controls (820.4 ± 402.8 and 1458.1 ± 210.0 compared with 193.1 ± 141.0 and 127.7 ± 21.9 ng/mg, resp.) (P < 0.001). There was significant correlation between serum and urinary levels of VDBP in total patient group. Receiver operating characteristic analysis of uVDBP levels showed optimum cut-off value of 216.0 ng/mg corresponding to 98.8% sensitivity and 80.0% specificity and an area under the curve of 0.973 to discriminate the normoalbuminuria from the microalbuminuria groups. In multivariate analysis, ordination plot showed obvious demarcation between the study groups caused by the higher levels of uVDBP and albumin/creatinine ratio among other variables. The study findings suggested a possible clinical application of uVDPB as an early and a good marker for the detection of early renal disease in type 2 DM Saudi patients. Large-scale validation studies are warranted to confirm the results before including uVDBP with the available list of other conventional biomarkers.