Cyclooxygenase-2 −765 G/C polymorphisms and susceptibility to hepatitis B-related liver cancer in Han Chinese population

To investigate the relationship of cyclooxygenase-2 (COX-2) polymorphisms [COX-2 −765 G/C (rs 20417)] and susceptibility to hepatitis B-related liver cancer in Han Chinese population. The polymorphisms of COX-2 −765 G/C was detected by polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) in 300 patients with hepatitis B, 300 patients with cirrhosis, 300 patients with primary liver carcinoma and 300 health controls. The COX-2 −765 G/C genotypes were GG, GC and CC. There frequencies in the hepatitis B patients were 80.33, 17.67 and 2.00%; in the cirrhosis patients were 77.67, 18.00 and 4.33%; in the patients with primary liver carcinoma were 65.67, 28.33 and 6.00% and in the heathy controls were 87.00, 12.33 and 0.67%, respectively, COX-2 −765 C allele carriers had an increased risk of hepatitis B-related liver cancer. COX-2 −765 C allele carriers having drinking history or family history of liver cancer had higher risk for HCC. COX-2 −765 C allele genotype, drinking history and family history of liver cancer may increase the susceptibility to hepatitis B-related liver cancer in Gansu province, China.     

TNF-alpha −308G/A and −238G/A polymorphisms and its protein network associated with type 2 diabetes mellitus

Several reports document the role of tumor necrosis factor alpha (TNF-α) and lipid metabolism in the context of acute inflammation as a causative factor in obesity-associated insulin resistance and as one of the causative parameter of type 2 diabetes mellitus (T2DM). Our aim was to investigate the association between −308G/A and −238G/A polymorphisms located in the promoter region of the TNF-α gene in T2DM in the Indian population with bioinformatics analysis of TNF-α protein networking with an aim to find new target sites for the treatment of T2DM. Demographics of 100 diabetes patients and 100 healthy volunteers were collected in a structured proforma and 3 ml blood samples were obtained from the study group, after approval of Institutional Ethics Committee of the hospital (IEC). The information on clinical parameters was obtained from medical records. Genomic DNA was extracted; PCR–RFLP was performed using TNF-α primers specific to detect the presence of SNPs. Various bioinformatics tools such as STRING software were used to determine its network with other associated genes. The PCR–RFLP studies showed that among the −238G/A types the GG genotype was 87%, GA genotype was 12% and AA genotype was 1%. Almost a similar pattern of results was obtained with TNF-α −308G/A polymorphism. The results obtained were evaluated statistically to determine the significance. By constructing TNF-α protein interaction network we could analyze ontology and hubness of the network to identify the networking of this gene which may influence the functioning of other genes in promoting T2DM. We could identify new targets in T2DM which may function in association with TNF-α. Through hub analysis of TNF-α protein network we have identified three novel proteins RIPK1, BIRC2 and BIRC3 which may contribute to TNF-mediated T2DM pathogenesis. In conclusion, our study indicated that some of the genotypes of TNF-α −308G/A, −238G/A were not significantly associated to type 2 diabetes mellitus, but TNF-α −308G/A polymorphism was reported to be a potent risk factor for diabetes in higher age (>45) groups. Also, the novel hub proteins may serve as new targets against TNF-α T2DM pathogenesis.     

Association of β-fibrinogen gene −148C/T and −455G/A polymorphisms and coronary artery disease in Chinese population: A Meta analysis

The purpose of our study was to evaluate the correlation between the β-fibrinogen gene −148C/T and −455G/A polymorphisms and susceptibility to coronary artery disease in the Chinese population using a meta-analytic approach. Eligible studies about this correlation were identified by searching the PubMed, EMBASE, and CNKI databases. Of the 13 identified, 7 (with 1488 cases and 1234 controls) involved the −148C/T polymorphism and 9 (with 1023 cases and 1081 controls) involved the −455G/A polymorphism. No publication bias was detectable and heterogeneity testing found significant differences between the ORs for both groups of studies. The combined OR for the 7 studies on susceptibility to coronary artery disease in −148T allele carriers compared to the −148C/C wild-type homozygotes was 1.31 (95%CI: 0.94–1.84, P=0.11). The combined OR for the 9 studies on susceptibility to coronary artery disease in −455A allele carriers compared to the −455G/G wild-type homozygotes was 1.75 (95%CI: 1.24–2.46, P=0.001). Our results suggest the absence of an association between the β-fibrinogen gene −148C/T polymorphism and susceptibility to coronary artery disease and the possibility that −455G/A polymorphism (in particular, allele A) increases susceptibility to this disease in the Chinese population.     

Apolipoprotein A1 −75 G/A and +83 C/T polymorphisms: susceptibility and prognostic implications in breast cancer

Apolipoprotein A1 (ApoA1) is the major apoprotein constituent of high-density lipoprotein that can play important roles in tumor invasion and metastasis. In the current report, we evaluated the role of the functional ApoA1 polymorphisms (−75 G/A and +83 C/T) as genetic markers for breast cancer susceptibility and prognosis. We used the polymerase chain reaction and restriction enzyme digestion (RFLP-PCR) to characterize the variations of the ApoA1 gene in 295 unrelated Tunisian patients with breast carcinoma and 197 healthy control subjects. No association was found between the +83 C/T genetic variation in ApoA1 gene and the risk of breast cancer occurrence. The presence of the (+83) T allele appeared however to be associated with an increased risk of lymph node metastasis occurrence (OR = 2.94; P = 0.01). Furthermore, a positive association was found between ApoA1 −75 A allele carriers and breast cancer risk (OR = 1.57; P = 0.02). Regarding prognostic indicators, a significant association was found between ApoA1 (−75) A allele carriers and the premenopausal status of breast cancer patients (OR = 1.73; P = 0.03). Additionally, the presence of the −75 A allele was correlated with the oestrogen receptor status among premenopausal women (OR = 2.45; P = 0.02). This is the first report on the studies of ApoA1 single nucleotide polymorphisms (SNPs) in breast carcinomas. Our data suggest that these genetic variations of ApoA1 may represent a marker for the increased risk of breast cancer.     

Association between the −11377 C/G and −11391 G/A polymorphisms of adiponectin gene and adiponectin levels with susceptibility to type 1 and type 2 diabetes mellitus in population from the west of Iran,correlation with lipid profile

Adipose tissue, an endocrine organ, secretes bioactive factors including adiponectin. Adiponectin is a protein hormone that enhances insulin sensitivity through increased fatty acid oxidation and inhibition of hepatic glucose production. We assessed the association of the adiponectin promoter region polymorphisms −11391 G/A and −11377 C/G with susceptibility to type 1 (T1DM) and type 2 (T2DM) diabetes mellitus in the population of west Iran. Also, we investigated the effect of adiponectin level and lipid profile on T1DM and T2DM development. In this case-control study, we recruited 189 patients with diabetes (100 T2DM and 89 T1DM) and 161 sex and age-matched unrelated healthy controls. Adiponectin mutations were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), and the protein level was measured by the enzyme-linked immunosorbent assay. Other biochemical parameters were determined by routine laboratory methods. The G allele of adiponectin gene at −11377 position (C/G) significantly increased the risk of T1DM. With respect to genotype models, codominant (2.97 times), dominant (3.6-fold), and over-codominant (2.9-fold) patients with T1DM who carried −11377 C > G single-nucleotide polymorphisms were significantly susceptible to the development of the disease. A significantly higher level of adiponectin in T1DM was oberved compared with the control group. In contrast, patients with T2DM had lower adiponectin levels compared with healthy controls. The genotype distributions of −11391 G/A polymorphisms were the same for patients with diabetes and control groups. The presence of G allele at −11377 C/G adiponectin gene significantly increased serum adiponectin level and may be a risk factor for T1DM susceptibility among the western Iranian population.     

Association of NADPH oxidase p22phox gene C242T, A640G and −930A/G polymorphisms with primary knee osteoarthritis in the Greek population

Osteoarthritis (OA) is the most common form of arthritis with still unknown pathogenic etiology and considerable contribution of genetic factors. Recently, a new emerging role of oxidative stress in the pathology of OA has been reported, lacking however elucidation of the underlying mechanism. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase being a complex enzyme produced by chondrocytes, presents the major source of reactive oxygen species and main contributor of increased oxidative stress. The present study aims to evaluate the association of NADPH oxidase p22phox gene C242T, A640G and ?A930G polymorphisms with primary knee OA in the Greek population. One hundred fifty five patients with primary symptomatic knee OA participated in the study along with 139 matched controls. Genotypes were determined using polymerase chain reaction and restriction fragment length polymorphism technique. Allelic and genotypic frequencies were compared between both study groups. NADPH p22phox ?A930G polymorphism was significantly associated with knee OA in the crude analysis (P = 0.018). No significant difference was detected for C242T and A640G polymorphisms (P > 0.05). The association between ?A930G polymorphism and knee OA disappeared when the results were adjusted for obesity (P = 0.078, odds ratio 0.54, 95 % CI 0.272–1.071). The interaction between all three polymorphisms was not significant. The present study shows that NADPH oxidase p22phox gene C242T, A640G and ?A930G polymorphisms are not risk factors for knee OA susceptibility in the Greek population. Further studies are needed to give a global view of the importance of this polymorphism in the pathogenesis of OA.     

Associations between TNF-α −308 A/G and lymphotoxin-α +252 A/G polymorphisms and susceptibility to sarcoidosis: a meta-analysis

Several studies have examined the effects of the tumor necrosis factor-α (TNF-α) ?308 A/G and lymphotoxin-α (LT-α) +252 A/G polymorphisms on susceptibility to sarcoidosis, showing mixed results. The purpose of this study was to examine whether the TNF-α ?308 A/G and LT-α +252 A/G polymorphisms confer susceptibility to sarcoidosis. We did a literature search from MEDLINE and EMBASE indices, and conducted a meta-analysis examining the association between TNF-α ?308 A/G and LT-α +252 A/G polymorphisms and sarcoidosis. A total of 13 separate comparisons including 1,396 patients with sarcoidosis and 2,344 controls were considered in our meta-analysis. The meta-analysis revealed a significant association between the TNF-α ?308 A allele and sarcoidosis (odds ratio [OR] = 1.480, 95 % confidence interval [CI] 1.057–2.073, p = 0.002). Stratification by ethnicity indicated an association between the TNF-α ?308 A allele polymorphism and sarcoidosis in Europeans (OR = 1.445, 95 % CI = 1.010–2.065, p = 0.044), but not Asians (OR = 4.693, 95 % CI = 0.548–40.29, p = 0.158). The results also showed a significant association between the LT-α +252 G allele and sarcoidosis (OR = 1.266, 95 % CI = 1.048–1.528, p = 0.014). Stratification by ethnicity indicated an association between the LT-α +252 G allele and sarcoidosis in Europeans (OR = 1.307, 95 % CI = 1.045–1.635, p = 0.019), but not in Asians (OR = 1.169, 95 % CI = 0.824–1.660, p = 0.381). Our meta-analysis demonstrates that the TNF-α ?308 A/G and LT-α +252 A/G polymorphisms are associated with susceptibility to sarcoidosis in an European population.     

Apo A5 −1131T/C, FgB −455G/A, −148C/T, and CETP TaqIB gene polymorphisms and coronary artery disease in the Chinese population: a meta-analysis of 15,055 subjects

The Apolipoprotein A5 (APO A5) ?1131T/C, fibrinogen β (FgB) ?455G/A, ?148C/T, and cholesteryl ester transfer protein (CETP) TaqIB gene polymorphisms have been indicated to be associated with the coronary artery disease (CAD) risk, but the individual study results are still inconsistent. To explore the relationship between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD in the Chinese population, the current meta-analysis involving 15,055 subjects from 40 individual studies was conducted. The pooled odds ratio (OR) for the association between APO A5 ?1131T/C, FgB ?455G/A, ?148C/T, and CETP TaqIB gene polymorphisms and CAD and its corresponding 95 % confidence interval (95 % CI) were evaluated by random or fixed effect model. A significant association between APO A5 ?1131T/C gene polymorphism and CAD in the Chinese population was found under an allelic (OR: 1.33, 95 % CI: 1.22–1.44, P < 0.00001), recessive (OR: 1.67, 95 % CI: 1.25–2.25, P = 0.0006), dominant (OR: 0.820, 95 % CI: 0.767–0.876, P = 1.0 × 10^?10), homozygous (OR: 2.36, 95 % CI: 1.55–3.58, P < 0.0001) and heterozygous genetic models (OR: 1.136, 95 % CI:1.075–1.200, P = 1.0 × 10^?10). A significant association between FgB ?455G/A gene polymorphism and CAD was also detected in the Chinese population under an allelic (OR: 1.50, 95 % CI: 1.25–1.81, P < 0.0001), dominant (OR: 0.864, 95 % CI: 0.819–0.912, P = 1.0 × 10^?10), homozygous (OR: 1.616, 95 % CI: 1.213–2.152, P = 0.001) and heterozygous genetic models (OR: 1.245, 95 % CI:1.138–1.361, P = 1.0 × 10^?10). No significant association was found between them under a recessive genetic model (OR: 1.124, 95 % CI: 0.844–1.497, P = 0.424). A significant association was also found between FgB ?148C/T gene polymorphism and CAD in the Chinese population under an allelic (OR: 1.34, 95 % CI: 1.06–1.71, P = 0.02), recessive (OR: 1. 65, 95 % CI: 1.02–2.69, P = 0.04), dominant (OR: 0.924, 95 % CI: 0.872–0.978, P = 0.007) and homozygous genetic models (OR: 0.968, 95 % CI: 0.942–0.995, P = 0.018). No significant association was found between them under a heterozygous genetic model (OR: 0.979, 95 % CI: 0.937–1.023, P = 0.342). In the whole Chinese population, no significant association between the CETP TaqIB gene polymorphism and CAD was found under an allelic (OR: 1.17, 95 % CI: 0.94–1.45, P = 0.15), dominant (OR: 1.46, 95 % CI: 0.80–2.67, P = 0.22) or recessive genetic models (OR: 0.68, 95 % CI: 0.32–1.44, P = 0.31). However, in the subgroup analysis stratified by ethnicity, there was a significant association between them under an allelic (OR: 1.27, 95 % CI: 1.07–1.52, P = 0.007) and dominant genetic model (OR: 2.04, 95 % CI: 1.49–2.79, P < 0.00001) in the Han subgroup. In the Chinese population, the APO A5 ?1131T/C and FgB ?455G/A, ?148C/T gene polymorphisms were implied to be associated with CAD susceptibility. The APO A5 ?1131C, FgB ?455A, and ?148T alleles might confer susceptibility to CAD. CETP TaqIB gene polymorphism was suggested to be associated with CAD susceptibility in the Chinese Han population. Carriers with B1 allele of CETP TaqIB gene might be predisposed to CAD in the Chinese Han population.     

Association between tumor necrosis factor-α promoter −308 A/G, −238 A/G, interleukin-6 −174 G/C and −572 G/C polymorphisms and periodontal disease: a meta-analysis

The aim of this study was to determine whether tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) promoter polymorphisms confer susceptibility to periodontitis in ethnically different populations. A literature search was performed using PubMed and Embase and a meta-analysis of the identified studies was conducted to explore the associations between TNF-α ?308 A/G, ?238 A/G, IL-6 promoter ?174 G/C and ?572 G/C polymorphisms and periodontitis. Seventeen comparison studies for the TNF-α ?308 A/G polymorphism and three studies for the TNF-α ?238 A/G polymorphism were included in the meta-analysis. And 16 separate studies for the IL-6 ?174 G/C polymorphism and 10 studies for the IL-6 ?572 G/C polymorphism were considered in our meta-analysis. Analysis after stratification by ethnicity indicated that the TNF-α ?308 A allele was associated with periodontitis in Brazilian, Asian, and Turkish populations (OR = 0.637, 95 % CI = 0.447–0.907, p = 0.013; OR = 0.403, 95 % CI = 0.204–0.707, p = 0.009; OR = 1.818, 95;  % CI = 1.036–3.189, p = 0.037). The meta-analysis showed no association between the TNF-α ?238 A/G polymorphism and periodontitis. The meta-analysis indicated an association of the IL-6 ?174 G/C polymorphisms with periodontitis in Brazilian populations (OR for GG + GC = 2.394, 95 % CI = 1.081–5.302, p = 0.031). Stratification by ethnicity and disease type indicated an association between the IL-6 ?572 G allele and chronic periodontitis (OR = 1.585, 95 % CI = 1.030–2.439, p = 0.036), and periodontitis in Europeans (OR = 2.118, 95 % CI = 1.254–3.577, p = 0.005). This meta-analysis demonstrates that the TNF-α ?308 A/G polymorphism confers susceptibility to periodontitis in Brazilian, Asian and Turkish populations. The IL-6 ?174 G/C polymorphism may confer susceptibility to periodontitis in Brazilians, and the IL-6 ?572 G/C polymorphism may be associated with susceptibility to periodontitis in Europeans, and chronic periodontitis.     

RARB and STMN2 polymorphisms are not associated with sporadic Creutzfeldt–Jakob disease (CJD) in the Korean population

Polymorphisms in the prion protein gene (PRNP) can affect the susceptibility of humans to prion diseases. Recently, aside from PRNP, single nucleotide polymorphisms (SNPs) of two candidate genes for susceptibility to human prion diseases have been identified by human genome-wide association studies (GWAS) in the British population. One SNP of retinoic acid receptor beta (RARB), which is correlated with prion disease incubation time in mice, was associated with human prion diseases such as variant and iatrogenic CJD in the British population. The other SNP of the gene that encodes SCG10 (STMN2), which is related to clinical onset of sporadic CJD, was also associated with variant CJD and kuru. In order to investigate whether two polymorphisms located in upstream of RARB and STMN2 are associated with sporadic CJD in the Korean population, we compared genotype and allele frequencies of these polymorphisms in 217 sporadic CJD patients and 216 healthy Koreans. The genotype distribution and allele frequencies in upstream of the RARB and STMN2 polymorphisms were not significantly different between healthy controls and Korean sporadic CJD patients. This finding indicates that the two SNPs are not correlated with genetic susceptibility to sporadic CJD in the Korean population. This is the first genetic association study of RARB and STMN2 with sporadic CJD in an Asian population.     

Serum amyloid A and inflammasome activation: A link to breast cancer progression?

Breast cancer is the most frequently diagnosed cancer in women globally. Although there have been many significant advances made in the diagnosis and treatment of breast cancer, numerous unresolved challenges remain, which include prevention, early diagnosis, metastasis and recurrence. The role of inflammation in cancer development is well established and is believed to be one of the leading hallmarks of cancer progression. Recently, the role of the inflammasome, a cytosolic multiprotein complex, has received attention in different cancers. By contributing to the activation of inflammatory cytokines the inflammasome intensifies the inflammatory cascade. The inflammasome can be activated through several pathways, which include the binding of pattern associated molecular patterns (PAMPs) and damage associated molecular patterns (DAMPs) to toll-like receptors (TLRs). Serum amyloid A (SAA), a non-specific acute-phase protein, can function as an endogenous DAMP by binding to pattern recognition receptors like TLRs on both breast cancer cells and cancer associated fibroblasts (CAFs). SAA can thus stimulate the production of IL-1β, thereby creating a favourable inflammatory environment to support tumour growth. The aim of this review is to highlight the possible role of SAA as an endogenous DAMP in the tumour microenvironment (TME) thereby promoting breast cancer growth through the activation of the NLRP3 inflammasome.     

LEP (−2548G>A LEP) and LEPR (223Gln>Arg, 109Lys>Arg) polymorphisms as breast cancer risk factors in the Polish female population

On a global scale, breast cancer is the most common type of cancer in women, and it is still a growing problem. Therefore, new prognostic or diagnostic markers are required that would facilitate the assessment of patients or provide more efficient therapy, respectively. In these studies, we analyzed the contribution of LEP (2548G>A) and LEPR (109 Lys>Arg and 223Gln>Arg) genes polymorphisms to the risk of breast cancer development. The study involved 209 women aged 59.6?±?11 years diagnosed with breast cancer and 202 healthy women aged 57.8?±?8.2 years, who were blood donors. Polymorphism were evaluated by PCR–RFLP reaction followed by the verification of part of the samples by sequencing. The results of the study confirmed obesity as a significant breast cancer development risk factor in Polish women. However, no significant association between the studied polymorphisms and breast cancer risk or severity of the neoplastic disease was found. Interestingly, it was shown that wild type 223Gln>Gln leptin receptor (LEPR) was statistically more common in women with human epidermal growth factor receptor 2 negative (HER2?) than human epidermal groth factor receptor 2 positive (HER2+) breast cancer and wild type form of 2548G>A LEP was more common in women with progesterone receptor positive (PR+) than progesterone receptor negative (PR?) breast cancer. Studied polymorphisms of the LEP and LEPR genes do not increase breast cancer risk in the population of Polish women. However, they can affect PR an HER receptors expression and thus the severity of the disease. Noteworthy, this interesting correlation is being reported for the first time and might constitute an essential contribution to the identification of molecular mechanisms of carcinogenesis.

     

Lack of association between interleukin-13 gene polymorphisms (−1055 C/T and +2044 G/A) in Iranian patients with lung cancer

Lung cancer is one of the leading causes of death from cancer. Both immune cells and tumor cells play a key role in lung cancer immunity by secretion of cytokines and developing type-2 cell-mediated immune response. IL-13 is an immunoregulatory cytokine affecting tumor immunosurveillance by deviation of immune response from Th1 to Th2. In the present study we sought to determine the association of single nucleotide polymorphisms (SNPs) of IL-13 gene at positions +2044 (G/A) and −1055 (C/T) and lung cancer. One hundred forty one patients and 113 controls were recruited; control group was subdivided into smoker and nonsmoker individuals for serum detection. Genotyping was carried out by PCR-RFLP assay and IL-13 detection by ELISA method. No statistically significant difference was found in the frequency of genotypes, alleles, and haplotypes at positions +2044 (G/A) and −1055 (C/T) of IL-13 gene between lung cancer patients and controls. Serum level of IL-13 was not detectable in both groups. The results of this study reveal that although +2044 (G/A) and −1055 (C/T) SNPs in IL-13 are implicated in some pulmonary processes, they do not confer susceptibility to lung cancer in Iranian population.     

IκBα polymorphisms were associated with increased risk of gastric cancer in a southern Chinese population: a case-control study

AimNuclear factor-kappa B inhibitor alpha (IκBα) polymorphisms were found to be associated with inflammatory diseases. However, the association between IκBα polymorphisms with gastric cancer is still unknown. We aim to investigate the association between IκBα polymorphisms and gastric cancer risk in a large population-based case–control study among southern Chinese.Main methodsA population-based case–control study was conducted between 1999 and 2006 in Guangdong Province, China. A total of 1010 gastric cancer patients and 1500 healthy controls were enrolled in this study. IκBα polymorphisms were identified by sequencing of IκBα gene ranging from the 2 kb promoter region to the 3.5 kb genomic region. Polymorphisms in IκBα were analyzed by TaqMan SNP genotyping assay.Key findingsrs17103265 deletion homozygote (?/?) had significantly increased gastric cancer risk (OR = 2.11, 95% CI = 1.17–3.83, P = 0.01), compared with rs17103265 T homozygote (TT). rs17103265 (?/?) genotype was significantly associated with increased risk of intestinal-type gastric cancer with (OR = 2.21, 95% CI = 1.19–4.08, P = 0.01), but not with the diffuse or mix type of gastric cancer. rs17103265 (?/?) was associated with poorly differentiated gastric cancer (OR = 2.05, 95% CI = 1.07–3.94, P = 0.03), but not with moderately or well differentiated gastric cancer. A significant decrease in luciferase activity was observed in rs17103265 deletion allele as compared with the vector containing the rs17103265 T allele (P < 0.0001). rs17103265 polymorphism was not associated with the prognosis of gastric cancer patients.SignificanceIκBα rs17103265 deletion homozygote is a novel genetic risk factor for gastric carcinogenesis, especially for the development of certain subtypes of gastric cancer in southern Chinese population.     

Clathrin-dependent APP endocytosis and Aβ secretion are highly sensitive to the level of plasma membrane cholesterol

Several lines of evidence support a strong relationship between cholesterol and Alzheimer's disease pathogenesis. Membrane cholesterol is known to modulate amyloid precursor protein (APP) endocytosis and amyloid-β (Aβ) secretion. Here we show in a human cell line model of endocytosis (HEK293 cells) that cholesterol exerts these effects in a dose-dependent and linear manner, over a wide range of concentrations (-40% to + 40% variations of plasma membrane cholesterol induced by methyl-beta-cyclodextrin (MBCD) and MBCD-cholesterol complex respectively). We found that the gradual effect of cholesterol is inhibited by small interference RNA-mediated downregulation of clathrin. Modulation of clathrin-mediated APP endocytosis by cholesterol was further demonstrated using mutants of proteins involved in the formation of early endosomes (dynamin2, Eps15 and Rab5). Importantly we show that membrane proteins other than APP are not affected by cholesterol to the same extent. Indeed clathrin-dependent endocytosis of transferrin and cannabinoid1 receptors as well as internalization of surface proteins labelled with a biotin derivative (sulfo-NHS-SS-biotin) were not sensitive to variations of plasma membrane cholesterol from -40% to 40%. In conclusion clathrin-dependent APP endocytosis appears to be very sensitive to the levels of membrane cholesterol. These results suggest that cholesterol increase in AD could be responsible for the enhanced internalization of clathrin-, dynamin2-, Eps15- and Rab5-dependent endocytosis of APP and the ensuing overproduction of Aβ.     

MCP-1 −2518 A/G functional polymorphism is associated with increased susceptibility to active pulmonary tuberculosis in Tunisian patients

Monocyte chemoattractant protein-1 (MCP-1) plays crucial role in protective immunity against Mycobacterium tuberculosis (MT). In this study, we examined whether single nucleotide polymorphism (SNP) −2518 A/G (rs 1024611) of MCP-1 affect the susceptibility to active tuberculosis (TB) in Tunisian populations. Genomic DNA from patients with active TB (168 cases of pulmonary TB and 55 cases of extrapulmonary TB) and ethnically controls (150 cases) was genotyped for the MCP-1 −2518 A/G SNP by polymerase chain reaction fragment length polymorphism (PCR-RFLP). We observed that −2518 G allele and GG genotype (high MCP-1 producer) frequencies were significantly more elevated in active pulmonary TB group in comparison to control group [34 vs. 22%; P = 0.0007; 15 vs. 5%, P corrected for the number of genotypes (Pc) = 0.015; respectively]. Additionally, they were associated with increased risk development of this clinical form of TB [odds ratio (OR) = 1.83, 95% confidence intervals (CI) = 1.26–2.66; OR = 3.1, 95% CI = 1.28–7.76; respectively]. However, wild type allele −2518 A and AA genotype were over-represented in control group (78 and 62%) and seem to be protective factors against TB. Moreover, −2518 AA genotype was more frequent in control group and was associated with resistance against development of active pulmonary TB (OR = 0.56, 95% CI = 0.35–0.89, Pc = 0.03). Our findings confirm the key role of −2518 A/G SNP of MCP-1 and support its association with resistance/susceptibility to the development of active pulmonary TB in the Tunisian population.     

Association of −604G/A and −501A/C Ghrelin and Obestatin Prepropeptide Gene Polymorphisms with Polycystic Ovary Syndrome

Ghrelin hormone has an important role in a wide range of metabolic and non-metabolic processes. Polymorphisms of ghrelin gene could be associated with a large number of diseases. The aim of this study was to evaluate the association of ?604G/A and ?501A/C polymorphisms in ghrelin and obestatin prepropeptide gene (GHRL) with polycystic ovary syndrome (PCOS) in a sample of Iranian women. One hundred and fifty-two women with PCOS and 162 age-matched apparently healthy women as control group were enrolled in this study. The study subjects were genotyped for polymorphisms in the ghrelin gene using polymerase chain reaction–restriction fragment length polymorphism-based methods. Biochemical parameters, serum prolactin, luteinizing hormone, follicle stimulating hormone, estradiol, and testosterone were estimated by chemiluminescence assay. Serum lipids and lipoproteins were determined by standard enzymatic methods. The association between the risk of PCOS and ghrelin gene polymorphisms was examined using Multivariate analysis. The frequency of the ?604G/A and ?501A/C polymorphisms was not statistically different between patients and the control group of women (p = 0.12 and p = 0.21, respectively). A significantly higher level of LDL-C was found in the wild-type AA genotype compared with CC genotype of ?501A/C polymorphism (p = 0.02). Our findings indicate that neither ?604G/A and nor ?501A/C polymorphisms of ghrelin gene are associated with PCOS, but suggest a relation between the presence of polymorphic allele of ?501A/C polymorphism and LDL-C level in a sample of Iranian women.     

The polymorphisms G(−174)C in IL6 gene and G(−1082)A in IL10 gene are associated with poor outcomes in patients with acute coronary syndrome

Association between the rates of poor outcomes in the patient cohort with acute coronary syndrome and polymorphisms G(?174)C in the IL6 gene and G(?1082)A in the IL10 gene were determined. In total, 1145 patients hospitalized for coronary artery disease to cardiological hospitals of Moscow, St. Petersburg, Kazan, Chelyabinsk, Perm, Stavropol, and Rostov-on-Don were examined. The mean observation period was 9.10 ± 5.03 months (maximal, 18 months). Analysis of the survival of the patients with acute coronary syndrome that carried allele A has demonstrated that the presence of IL10 gene polymorphism G(?1082)A is associated with more frequent poor outcomes as compared with GG genotype. The survival time to endpoint for the carriers of GA and AA genotypes was 11.68 ± 0.67 months versus 12.69 ± 0.65 months for the carriers of GG genotype in IL10 gene (χ² = 4.13, p = 0.042). As for the IL6 gene polymorphism G(?174)C, survival rate analysis did not detect any significant association with the risk for poor outcome. However, joint analysis of these polymorphisms in both genes has demonstrated that characteristic of the patients with acute coronary syndrome that carry GG genotype of IL6 gene and GA and AA genotypes of IL10 is a higher rate of poor outcomes (time to endpoint, 11.01 ± 1.24 months) as compared with the carriers of IL6 gene CC and CG genotypes and IL10 gene GG genotype (time to endpoint, 13.28 ± 0.83 months (ξ² = 10.23, p = 0.017). These data suggest that the genes IL6 and IL10, whose products are involved in the control of inflammatory response, play an important role by increasing the probability of poor outcomes in the patients with acute coronary syndrome.