Importance of Circ0009910 in colorectal cancer pathogenesis as a possible regulator of miR-145 and PEAK1.

INTRODUCTION: Colorectal cancer (CRC) is one of the most frequent neoplasms in the world. Based on the emerging role of noncoding RNAs, particularly circular RNAs in pathogenesis of cancers, we designed this study to inspect the expression levels of a circ0009910-mediated regulatory pathway in colorectal cancer. METHODS: After bioinformatics analyses and construction of putative circ0009910/ miR-145-5p/PEAK1 pathway, the expression levels of these components were evaluated in 50 CRC tissues and adjacent specimens by quantitative real-time PCR. Moreover, we appraised the correlation coefficients between these transcripts and calculated the correlation between circ0009910 expression levels with clinicopathological features of patients. RESULTS: Circ0009910 and PEAK1 were significantly upregulated, while miR-145-5p was decreased in CRC samples compared with adjacent tissues (p < 0.05). Moreover, statistically significant correlations were observed between expression levels of circ0009910, miR-145-5p, and PEAK1. We also reported considerable correlations between circ0009910 expression and clinicopathological parameters including sex and perineural invasion. Finally, ROC curve analysis showed circ0009910 level as a discriminative biomarker for CRC. CONCLUSION: For the first time, we could introduce circ0009910 as an important biomarker in CRC. Collectively, this investigation helped us to identify a newly diagnosed pathway in CRC that can be a potential axis for designing effective drugs for treatment of CRC patients.

Association between polymorphism of GSTP1, GSTT1, GSTM1 and CYP2E1 genes and susceptibility to benzene-induced hematotoxicity.

Occupational exposure to benzene has been associated with leukemia, anemia, leukopenia, and thrombocytopenia. Genetic susceptibility to benzene toxicity in humans may be related to variations in benzene metabolizing genes. The main objective of this study was to ascertain whether polymorphism of GSTP1, GSTM1, GSTT1 and CYP2E1 genes might influence susceptibility to the adverse effects of benzene among employees of a petrochemical plant. In this cross-sectional study, 124 employees of a petrochemical plant who had been occupationally exposed to benzene and had one or more abnormal hematological parameter (cases) and 184 subjects with a similar exposure scenario, free from any abnormal hematological parameters (referent) were studied. Atmospheric concentrations of benzene were measured and GSTM1 and GSTT1 genotypes were evaluated using the multiplex polymerase chain reaction (PCR) technique. Additionally, GSTP1 and CYP2E1 genotypes were determined by PCR- restriction fragment length polymorphism (PCR-RFLP). The frequency of null GSTT1 genotype in cases was significantly higher than that of referent group (32.3 vs. 18.5%, OR 2.1, 95% CI 1.23-3.56, p = 0.004). The mean value of platelets in subjects with null GSTT1 genotype was significantly lower than that of individuals with positive GSTT1 genotype (p = 0.015). Conversely, the mean value of leukocytes was significantly higher in subjects with null GSTM1 genotype as compared to those with positive GSTM1 genotype (p = 0.026). Logistic regression analysis showed that, subjects with null GSTT1 genotype had a significantly higher risk for hematological disorders, as compared to those with positive GSTT1 genotype (OR 2.1, 95% CI 1.23-3.56). Moreover, subjects with both null GSTT1 and GSTM1 genotypes had a significantly higher risk for hematological disorders as compared to subjects with positive GSTT1 and GSTM1 genotypes (OR 2.35, 95% CI 1.14-4.8). The results of this study showed that, individuals carrying null GSTT1 or both null STT1 and GSTM1 genotypes had a higher risk and were more susceptible to benzene-induced hematological disorders.

Melatonin may play a role in modulation of bax and bcl-2 expression levels to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

The close relationship between free radicals effects and apoptosis process has been proved. Melatonin has been reported as a direct free radical scavenger. We investigated the capability of melatonin in the modification of radiation-induced apoptosis and apoptosis-associated upstream regulators expression in rat peripheral blood lymphocytes. Rats were irradiated with a single whole body Cobalt 60-gamma radiation dose of 8Gy at a dose rate of 101cGy/min with or without melatonin pretreatments at different concentrations of 10 and 100mg/kg body weight. The rats were divided into eight groups of control, irradiation-only, vehicle-only, vehicle plus irradiation, 10mg/kg melatonin alone, 10mg/kg melatonin plus irradiation, 100mg/kg melatonin alone and 100mg/kg melatonin plus irradiation. Rats were given an intraperitoneal (IP) injection of melatonin or the same volume of vehicle alone 1h prior to irradiation. Blood samples were taken 4, 24, 48 and 72h after irradiation for evaluation of flow cytometric analysis of apoptotic lymphocytes using Annexin V/PI assay and measurement of bax and bcl-2 expression using quantitative real-time PCR (RT(2)qPCR). Irradiation-only and vehicle plus irradiation showed an increase in the percentage of apoptotic lymphocytes significantly different from control group (P<0.01), while melatonin pretreatments in a dose-dependent manner reduced it as compared with the irradiation-only and vehicle plus irradiation groups (P<0.01) in all time points. This reduced apoptosis by melatonin was related to the downregulation of bax, upregulation of bcl-2, and therefore reduction of bax/bcl-2 ratio. Our results suggest that melatonin in these doses may provide modulation of bax and bcl-2 expression as well as bax/bcl-2 ratio to protect rat peripheral blood lymphocytes from gamma irradiation-induced apoptosis.

The potential roles of lncRNAs DUXAP8, LINC00963, and FOXD2-AS1 in luminal breast cancer based on expression analysis and bioinformatic approaches.

Numerous studies have demonstrated that lncRNAs participate in regulatory networks of different cancers. Dysregulation of various lncRNAs such as DUXAP8, LINC00963, and FOXD2-AS1 has been reported in the development of various cancers. The aim of this study was investigation of the importance and potential roles of DUXAP8, LINC00963, and FOXD2-AS1 in ER+ breast cancer (BC). We examined the expression levels of DUXAP8, LINC00963, and FOXD2-AS1 in 71 luminal A and B tumor tissues and two luminal A cell lines (MCF7 and T47D) compared with adjacent non-tumor tissues and MCF10A cell line by qRT-PCR assay, respectively. For identifying the relation between three lncRNAs and luminal BC, bioinformatic analyses were performed using some databases and software including GENEVESTIGATOR software, GEPIA2, DAVID, REVIGO, STRING, lncATLAS, Kaplan-Meier plotter, starBase, and miRNet tool. The results showed the significant upregulation of all three lncRNAs in luminal A and B tumor specimens and cell lines. Upregulation of DUXAP8 and FOXD2-AS1 was significantly associated with progesterone receptor-positive (PR+) and p53 protein expression in luminal BC patients, respectively. Based on bioinformatic analyses, DUXAP8 can be considered as a prognostic biomarker for patients with luminal BC. DUXAP8, LINC00963, and FOXD2-AS1 are involved in several cancer-associated signaling pathways and multiple cancer-related processes. In addition, bioinformatic analyses indicated that LINC00963/hsa-mir-130a-3p/HSPA8 axis might have potential regulatory role in BC. In conclusion, dysregulation of DUXAP8, LINC00963, and FOXD2-AS1 can play roles in the development of luminal BC. They may exert their functions through involvement in some cancer signaling pathways and processes. In addition, they may interact with miRNAs like predicted interaction of LINC00963 with miR-130a-3p.

In vitro modulation of TCF7L2 gene expression in human pancreatic cells.

Several studies have recently reported strong association between type 2 diabetes and variation in the transcription factor 7-like 2 (TCF7L2) gene, which has been confirmed by several other genome-wide studies. However, the physiological implications of this transcription factor on the pathogenesis of type 2 diabetes is not yet known. The aim of this study was to investigate the alteration in TCF7L2 gene expression in human pancreatic cell line in response to various factors in vitro. MIA Paca-2 cell line (Human Pancreas cell line) was cultured in the presence of curcumin, lipopolysaccaride and glucose (low and high concentration). TCF7L2 gene expression was determined using quantitative real-time RT-PCR. Treatment with curcumin significantly increased TCF7L2 gene expression to 3.24 fold (1.7-log fold) (P = 0.003) compared to the controls while treatment with LPS decreased TCF7L2 gene expression to 0.88-fold (-0.18-log). On the other hand, glucose increased TCF7L2 gene expression in pancreatic cell line. Our data suggest a role for TCF7L2 in glucose homeostasis. The contrary effect of curcumin and LPS on expression of TCF7L2 in pancreatic cells supports a role for TCF7L2 in their survival and function in inflammatory conditions.

Cinemedicine: Using movies to improve students' understanding of psychosocial aspects of medicine.

BACKGROUND: There are rising concerns about how to teach psychosocial aspects of medicine to students. The aim of the study was the use of "cinemedicine" as a tool and technique in teaching psychosocial aspects of medicine to medical students at Tehran University of Medical Sciences (TUMS). METHODS: This was an educational study with quantitative and qualitative data analysis. Two hundred seventy medical students participated in this study. Nine sessions were held to teach psychosocial subjects in medicine using movies. Each session began with an initial explanation of the program objectives. After the show, medicine related points of the movie were discussed and analyzed by experts and students. In the end, questionnaires were distributed to assess the students' perceptions. RESULTS: The results of our study show that most of the students (84%) stated that teaching these subjects through movies was a nice event comparing to usual lectures. 56.5% of the students agreed with the application of points learned in the events in professional performance. The majority of the students (72.8%) agreed that participating in those events was useful for them as a physician and they would advise other students to attend to later sessions. Content analysis of the students' notes uncovered three categories of cinemedicine: "learning by observation", "creation of a supportive and tangible learning" and "motivation for learning". CONCLUSION: Cinemedicine provides the opportunity for medical students to learn psychosocial subjects related to medicine through observing and reflecting on movies.

Radioprotective effect of melatonin on expression of Cdkn1a and Rad50 genes in rat peripheral blood.

OBJECTIVE: Ionizing radiation is a critical threat to biomolecules, especially DNA. Various combinatorial compounds have been studied to protect this biomolecule. Melatonin has been reported as a direct and indirect free radical scavenger, but in this study, we explored the effect of melatonin on assisting in DNA repair by expression of Cdkn1a and Rad50; both of these genes are involved in DNA repair signaling, induced by radiation in rat peripheral blood. MATERIALS AND METHODS: Rats were irradiated with single whole-body linear accelerator X-ray radiation doses of 2 and 8 Gy with or without melatonin (100 mg/kg body weight) pretreatments. The rats were randomly divided into nine groups and given an intraperitoneal injection of melatonin or the same volume of vehicle alone 1 h before radiation. Blood samples were taken 8, 24, and 48 h postradiation to measure gene expression of Cdkn1a and Rad50 using quantitative reverse transcription polymerase chain reaction technique. RESULTS: Melatonin pretreatment increased the expression of Cdkn1a and Rad50 in 8 and 24 h postradiations (2 and 8 Gy) (P < 0.05), and there was no significant difference in 48 h postradiation compared to the radiation-only and vehicle plus radiation (2 and 8 Gy) groups. CONCLUSIONS: Based on our results, pretreatment with melatonin (100 mg/kg) may ameliorates injurious effects of 2 and 8 Gy ionization radiation by increasing the expression level of Cdkn1a and Rad50 in rat peripheral blood and assist in DNA double-strand breaks repair, especially during the early postradiation.

Effects of Genetic Polymorphism on Susceptibility to Nephrotoxic Properties of BTEXs Compounds.

OBJECTIVE: The aim of this study was to ascertain whether genetic polymorphism affects susceptibility of individuals to nephrotoxic potentials of benzene, toluene, ethyl-benzene, and xylenes (BTEXs). METHODS: Fifty BTEXs exposed workers with one or more abnormal parameter of kidney function and 232 referent subjects, with similar exposure history, free from any abnormal kidney parameters were investigated. Atmospheric concentrations of BTEXs were measured. In addition, genetic polymorphisms were determined by multiplex polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP). RESULTS: The frequencies of GSTP1 Ile-Val/Val-Val, null GSTT1, and null GSTT1/GSTM1 genotypes and mean values of blood urea nitrogen and plasma creatinine were significantly higher, while average glomerular filtration rate was significantly lower in cases than in referent subjects. CONCLUSION: These findings indicate that individuals carrying null GSTT1 or null GSTT1/GSTM1 are more susceptible to nephrotoxic properties of BTEXs compounds.

Modulation of Radiation-induced Base Excision Repair Pathway Gene Expression by Melatonin.

OBJECTIVE: Approximately 70% of all cancer patients receive radiotherapy. Although radiotherapy is effective in killing cancer cells, it has adverse effects on normal cells as well. Melatonin (MLT) as a potent antioxidant and anti-inflammatory agent has been proposed to stimulate DNA repair capacity. We investigated the capability of MLT in the modification of radiation-induced DNA damage in rat peripheral blood cells. MATERIALS AND METHODS: In this experimental study, male rats (n = 162) were divided into 27 groups (n = 6 in each group) including: irradiation only, vehicle only, vehicle with irradiation, 100 mg/kg MLT alone, 100 mg/kg MLT plus irradiation in 3 different time points, and control. Subsequently, they were irradiated with a single whole-body X-ray radiation dose of 2 and 8 Gy at a dose rate of 200 MU/min. Rats were given an intraperitoneal injection of MLT or the same volume of vehicle alone 1 h prior to irradiation. Blood samples were also taken 8, 24, and 48 h postirradiation, in order to measure the 8-oxoguanine glycosylase1 (Ogg1), Apex1, and Xrcc1 expression using quantitative real-time-polymerase chain reaction. RESULTS: Exposing to the ionizing radiation resulted in downregulation of Ogg1, Apex1, and Xrcc1 gene expression. The most obvious suppression was observed in 8 h after exposure. Pretreatments with MLT were able to upregulate these genes when compared to the irradiation-only and vehicle plus irradiation groups (P < 0.05) in all time points. CONCLUSION: Our results suggested that MLT in mentioned dose may result in modulation of Ogg1, Apex1, and Xrcc1 gene expression in peripheral blood cells to reduce X-ray irradiation-induced DNA damage. Therefore, administration of MLT may increase the normal tissue tolerance to radiation through enhancing the cell DNA repair capacity. We believed that MLT could play a radiation toxicity reduction role in patients who have undergone radiation treatment as a part of cancer radiotherapy.

The radioprotective effect of metformin against cytotoxicity and genotoxicity induced by ionizing radiation in cultured human blood lymphocytes.

Metformin is a widely prescribed drug used in the treatment of patients with type 2 diabetes. In this study, the radioprotective effect of metformin was investigated against cytotoxicity and genotoxicity induced by ionizing radiation (IR) in human peripheral blood lymphocytes. Human lymphocytes were treated with metformin at concentrations 10 and 50µM for 2h and irradiated with 6MV X-rays. The radiation antagonistic potential of metformin was assessed by MTT [3-(4,5-dimethyl-2-thiaozolyl)-2,5-diphenyl-2H tetrazolium bromide] assay, chromosomal aberration (CA) analysis, cytokinesis blocked micronucleus (CBMN) assay, and flow cytometry. Observations demonstrated a radiation-dose-dependent decrease in the percentage of cell viability after 24h. It was found that pretreatment with metformin (10 and 50µM) increased the percentage of cell viability. A highly significant dose modifying factor (DMF) 1.35 and 1.42 was observed for 10 and 50µM metformin, respectively. Metformin (10 and 50µM) pretreatment significantly decreased the frequency of dicentrics (DCs), acentric fragments (AFs), rings (RIs), micronuclei (MN), and nucleoplasmic bridges (NPBs) in irradiated human peripheral blood lymphocytes. Also, treatment with metformin (10 and 50µM) without irradiation did not increase the number of MN, NPBs, DCs, AFs, RIs, and did not show a cytostatic effect in the human peripheral blood lymphocytes. On the other hand, metformin treatment (10 and 50µM) 2h prior to irradiation significantly reduced X-radiation-induced apoptotic incidence in human lymphocytes. The present study demonstrates metformin to be an effective radioprotector against DNA damage and apoptosis induced by IR in human lymphocytes. These data have an important application for the protection of lymphocytes from the genetic damage and side-effects induced by radiotherapy in cancer patients.

TNF-α and IFN-γ gene variation and genetic susceptibility to type 1 diabetes and its microangiopathic complications.

BACKGROUND: TNF-α has accelerating role in development of type 1 diabetes. Although an immunosupressor function and leading protecting role in T1DM also has been claimed for this pro-inflammatory cytokine. Over-expression of pro-inflammatory and type 1 cytokines (Th1, like IFN-γ) drive insulitis toward the destructive form that leads to type 1 diabetes (T1DM). Among type 1 cytokines only IFN-γ has been detectable in the islet ß cells. In deletion studies IFN-γ was also the only Th1 cytokine for which its ablation or blockade caused delayed or decreased incidence of T1DM. METHODS: Functional polymorphisms of TNF-α at position -308*G/A and at position +874*T/A of IFN-γ gene were employed as markers and the comparative distribution of derived genotypes/alleles were assessed in 248 British Caucasian T1DM patients and 118 healthy controls. RESULTS: There was no significant association between IFN-γ gene polymorphism and T1DM or the diabetic complication triad. There was a marginal association between TNF-α -308*G/A polymorphism in nephropaths (vs healthy controls) (p = 0.06), which its insignificancy may be due to survivor factor. No significant association was evident between the genotype/allele of the applied marker and T1DM or diabetic complication triad. CONCLUSION: Our results are in contrast with previous reports suggesting that these polymorphisms are not related to T1DM. This study also underlines the importance of replication of association studies to confirm the previous interpretation.

TGF-ß1 and IGF-I gene variations in type 1 diabetes microangiopathic complications.

BACKGROUND: Growth factors are generally believed to have a perpetuating role in the development of diabetic complications, However there is ample of evidence of a protective or therapeutic potential for some of them. IGF-I, according to some reports, may contribute to complication development, although a protective role for IGF-I has been claimed for all late diabetic complications, making it an exception among growth factors. Transforming growth factor (TGF)-ß1 as a pleiotropic cytokine is a key player in immunoregulation. Dysregulation of TGF-ß1 in diabetes has been addressed as a leading event of kidney pathologies, while there is no similar pivotal role for TGF-ß1 in diabetic retinopathy or neuropathy. An association study was conducted to evaluate the distinctive roles of TGF-ß1 and IGF-I in T1DM microvascular complications by gene variation-based regulatory mechanisms that are operational in modulation of both in situ and systemic levels of the gene product. METHODS: Two polymorphisms of the IGF-I gene at positions -383*C/T and -1089*C/T and two functional TGF-ß1 gene polymorphisms, including codons 10 (+869*C/T) and 25 (+915*G/C) were examined in 248 British Caucasian T1DM patients and 113 healthy controls. RESULTS: The distribution of IGF-1 gene polymorphisms did not reflect any significant association with different endpoints among the cases or different subgroups (complication triad) and controls. For TGF-ß1 gene codon 25 polymorphism the low producer variant (allele C) were more frequent in cases than controls, which is compatible with the anti-inflammatory role of TGF-ß1 and for codon 10 polymorphism the frequency of allele C was highest in retinopaths and, on the contrary and expectedly, nephropathy was more frequently accompanied by allele T (high producer). The frequency of allele G (high producer) of codon 25 polymorphism was slightly higher in the complication free group than in other subgroups. CONCLUSION: Although there were some differences in distribution of allele and genotype frequencies of TGF-ß1 gene polymorphism in diabetes microvascular complications the differences were not statistically significant. Regarding IGF-1 our result firstly questions the functionality of the employed polymorphic marker and secondly may entail that the main regulator of IGF-I functionality resides elsewhere rather than the IGF-I gene itself, such as post-transcriptional regulation.

Novel human mitochondrial tRNA phe mutation in a patient with hearing impairment: a case study.

We present a patient with non-syndromic and sensorineural hearing impairment with a novel mitochondrial DNA transition. A 7-year-old boy showed progressive deafness. He gradually lost his hearing ability and his hearing function did not improve with hearing aids. Laboratory data revealed normal blood lactate and pyruvate levels. Genetic analyses for mitochondrial DNA and GJB2 and GJB6 genes were performed. Mitochondrial genes analysis revealed a novel heteroplasmic nucleotide substitution, m.628C>T, in the phenylalanine transfer RNA gene. This case study reveals m.628C>T transition as a novel mitochondrial nucleotide change which may be important in mitochondrial deafness.

TGF-ß and IL-23 gene expression in unstimulated PBMCs of patients with diabetes.

The protective effects of TGF-ß have been documented in various autoimmune diseases, mostly in organ-specific autoimmunity including type 1 diabetes mellitus (T1DM). However, TGF-ß also plays a role as a pro-inflammatory mediator by induction of Th17 cytokine production. IL-23 also plays a key role in differentiation of Th17 cells, which are implicated in pathogenesis of autoimmune conditions including T1DM. The aim of this study was to investigate and compare the difference in the level of TGF-ß1 and IL-23 gene expression in unstimulated peripheral blood mononuclear cells (PBMCs) of patients with different forms of diabetes compared with normal healthy controls subjects. Patients with T1DM were grouped as early-onset T1DM (N = 20) with age at diagnosis <18 years and late-onset T1DM (N = 20) with the age at onset >18 years. Patients with T2DM (N = 20) and normal healthy controls (N = 20) were recruited from the same area. TGF-ß1 and IL-23 gene expression in fresh unstimulated PBMCs was determined in each group using quantitative real-time PCR. The results confirmed that a significant difference in TGF-ß1 and IL-23 gene expression was observed in both forms of juvenile-onset T1DM and adult-onset T1DM compared to the controls and T2DM patients. There was no significant difference for TGF-ß gene expression in patients with T2DM and controls. We therefore conclude that our results support the previous data on TGF-ß gene down-regulation in T1DM. Also up-regulation of IL-23 has been observed in T1DM whilst it was down-regulated in T2DM. We also found no significant difference between juvenile-onset and adult-onset T1DM indicating same mechanism might be involved in the pathogenesis of both types. More studies on different cytokines in Th17 pathways are required to further confirm our finding.

IL-23 gene expression in PBMCs of patients with coronary artery disease.

OBJECTIVE: Both adaptive and innate immune systems are involved in coronary artery disease (CAD). The aim of this study was to evaluate TH17 cytokines expression profiles in un-stimulated peripheral blood lymphocytes (PBMCs) of patients with coronary artery disease. METHODS: Expression profiles of IL-17, IL-23, and TGF-ß1 were determined in individuals with and without CAD using Real-time PCR. RESULTS: A significant decrease in IL-23 gene expression in un-stimulated PBMCs of patients with CAD compared to those without CAD was found (p=0.003, OR=0.045, 95% CI: 0.006-0.355). CONCLUSION: Our data reinforce the potential role of the IL-23 as a critical regulatory molecule that bridges the innate and adaptive arms of the immune system in the complex mechanisms associated with the development of atherosclerosis.

Poly thymidine polymorphism and cystic fibrosis in a non-Caucasian population.

BACKGROUND: Cystic fibrosis is a monogenic recessive disorder found predominantly in Caucasian population. This disease arises from mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In this study we consider poly T polymorphism c.1210-12T[5], c.1210-12T[7], c.1210-12T[9] (T{5}, T{7}, T{9}) in the intron 8 of CFTR gene in normal individuals and cystic fibrosis patients in the north of Iran. MATERIAL AND METHODS: 40 CF patients and 40 normal individuals were screened for poly T polymorphism in intron 8 of CFTR gene using Reverse Dot Blot method which was also used to detect p.Phe508del among CF patients. RESULTS: T{7} allele is the most prevalent in both normal and CF patients. Its abundance is approximately 75%. T{9} and T{5} represent approximately 20% and 5% of alleles respectively. T{7}/T{7} genotype is the most present in both normal and CF patients with 72.5% and 60% prevalence respectively. p.Phe508del was present in 13 CFTR alleles belonging to 7 patients with either homozygote T{9}/ T{9}, T{7}/ T{7} or compound heterozygote T{7}/ T{9} genotypes. CONCLUSION: Contrary to the Caucasians, T{7} allele is more frequent in Northern Iranian CF patients. The presence of p.Phe508del and T{7} allele in the same framework is reported for the first time in this part of the world. Further investigations of other populations will help to understand whether p.Phe508del arose by selection pressure in this part of the world or was imported from European countries. The abundance of T{5}, T{7}, T{9} alleles indicates that this polymorphism can be used as one of the informative markers for detection of normal and mutant alleles in prenatal diagnosis or carrier assessment in families with previous history of the disease in regions with high degree of CFTR mutation heterogeneity.

Endothelial nitric oxide synthase VNTR (intron 4 a/b) polymorphism association with type 2 diabetes and its chronic complications.

UNLABELLED: SUBJECT AND AIMS: Endothelial derived nitric oxide (eNOS) is involved in several functions playing important role in development of type 2 diabetes and insulin resistance. The aim of this study was to examine the association between eNOS intron 4 VNTR polymorphism and type 2 diabetes in an Iranian population. METHODS: A total of 220 patients with type 2 diabetes and 96 healthy control subjects were recruited from the same area. Genotyping was performed using PCR. RESULTS: A significant difference was found in genotype frequencies of eNOS polymorphism between patients and controls (aa+ab vs. bb p=0.02, OR 2.0 95% CI; 1.05-3.96). Also allele a frequency was significantly increased in patients with diabetes compared with controls (p=0.007, OR 2.1 95% CI; 1.19-4.08). We found that in patients with diabetic neuropathy the frequency of 'a' allele was significantly increased compared to the controls p=0.03, OR=1.8 95% CI (1.00-3.7). Both genotype and allele frequencies were significantly different between patients who were complication free compared to the controls [aa+ab vs. bb p=0.007, OR=2.6 95% CI (1.2-5.8) and p=0.001, OR=2.8 95% CI (1.4-5.9)] respectively with the a allele conferring the risk. CONCLUSION: The association between eNOS VNTR polymorphism and T2DM seems to be stronger in patients without diabetic complications indicating diverse effect of eNOS polymorphism on diabetes and diabetic microvascular complications.

eNOS gene polymorphism association with retinopathy in type 1 diabetes.

PURPOSE: Nitric oxide (NO) is a major mediator in vascular biology, regulating blood pressure and regional blood flow. NO and the enzymes required for its production may contribute to the aetiology of vascular pathologies. In diabetes, over-production of NO might play a role in the development of diabetic nephropathy, while reduced NO production may be related to the development of diabetic retinopathy and neuropathy, where VEGF (vascular endothelial growth factor) levels are increased in a counter regulatory manner. Among the three nitric oxide synthase (NOS) enzymes most attention has focussed on endothelial NOS (eNOS) because of its relevance to angiopathies. METHODS: In this study the influence of a single nucleotide polymorphism at position -786 in the eNOS gene, where there is a C/T base substitution, on development of type 1 diabetes mellitus (T1DM) and its microvascular complications was studied in 249 British Caucasian type 1 diabetics using a case-control association design. Genotyping was carried out using PCR-RFLP technique. RESULTS: There was a significant association between the polymorphism -786*C/T and both T1DM and diabetic retinopathy. The distribution of eNOS gene polymorphism genotype frequencies showed a significant difference observed between diabetic patients and healthy controls [CC+CT vs. TT p = 0.05, OR = 1.5 95%CI(0.9-2.5)]. The genotype frequencies for eNOS gene polymorphism was also significantly different between diabetic retinopaths and healthy controls [CC+CT vs. TT p = 0.0000 OR = 3.4 95%CI(1.9-6.1) No significant differences for eNOS allele and genotype frequencies were found in other groups compared to the controls. CONCLUSION: Therefore, eNOS gene variation may be a factor in the genetic propensity to T1DM and diabetic retinopathy that may have a prognostic value or may suggest interventional approaches to regulate eNOS in patients with diabetes.

HLA-DR association in papillary thyroid carcinoma.

OBJECTIVE: Papillary thyroid carcinoma (PTC) is the most frequent types of thyroid malignancies. Several genes may be involved in susceptibility of thyroid cancer including Human Leukocyte Antigens (HLA). The association of thyroid carcinoma with HLA alleles has been previously studied in other populations and certain HLA alleles were shown to be either predisposing or protective. The aim of this study was to determine the association between HLA-DR and papillary thyroid carcinoma in an Iranian population. DESIGN: HLA-DR antigen frequencies were determined in patients with papillary thyroid carcinoma (N=70) and non-related healthy controls (N=180) using PCR -SSP. MAIN OUTCOME: We found that HLA-DRB1*04 frequency was significantly higher in our patients compared to the controls [P=0.02, OR; 1.9, 95% CI (1.04-3.57)]. CONCLUSIONS: Our results revealed HLA-DRB1*04 as predisposing factor in papillary thyroid carcinoma in Iranian population. This confirms the previous findings for associations between HLA-DRB1 and differentiated carcinomas in other populations.