Single nucleotide polymorphisms in monocyte chemoattractant protein-1 and its receptor act synergistically to increase the risk of carotid atherosclerosis

CCL2, CCR2 Gene Variants and CCL2, CCR2 Serum Levels Association with Age-Related Macular Degeneration

Background: Age-related macular degeneration (AMD) is the most common cause of progressive and irreversible blindness in developed countries. Although the pathogenesis is not fully understood, AMD is a multifactorial pathology with an accumulation of inflammatory components and macrophages and a strong genetic predisposition. Our purpose was to investigate the association between early AMD and CCL2 (rs1024611, rs4586, rs2857656) and CCR2 (rs1799865) single nucleotide polymorphisms (SNPs) and CCL2, CCR2 serum levels in a Lithuanian population. Methods: The study included 310 patients with early AMD and 384 healthy subjects. Genotyping of CCL2 rs1024611, rs4586, rs2857656, and CCR2 rs1799865 was performed using a real-time polymerase chain reaction method, while CCL2 and CCR2 chemokines serum concentrations were analyzed using an enzyme-linked immunosorbent assay. Results: We found that the G allele at CCL2 rs1024611 was more prevalent in the early AMD group than in controls (29.2% vs. 24.1%, p = 0.032). Similarly, the C allele in CCL2 rs2857656 is more common in the early AMD group than in controls (29.2% vs. 24.2%, p = 0.037). Binomial logistic regression revealed that each G allele in rs1024611 was associated with 1.3-fold increased odds of developing early AMD under the additive model (OR = 1.322; 95% CI: 1.032–1.697, p = 0.027) as was each C allele in rs2857656 under the additive model (OR = 1.314; 95% CI: 1.025–1.684, p = 0.031). Haplotype analysis revealed that the C-A-G haplotype of CCL2 SNPs was associated with 35% decreased odds of early AMD development. Further analysis showed elevated CCL2 serum levels in the group with early AMD compared to controls (median (IQR): 1181.6 (522.6) pg/mL vs. 879.9 (494.4) pg/mL, p = 0.013); however, there were no differences between CCR2 serum levels within groups. Conclusions: We found the associations between minor alleles at CCL2 rs1024611 and rs2857656, elevated CCL2 serum levels, and early AMD development.

Adaptive Immune Response Signaling Is Suppressed in Ly6Chigh Monocyte but Upregulated in Monocyte Subsets of ApoE-/- Mice — Functional Implication in Atherosclerosis

Rationale

Inflammatory monocyte (MC) subset differentiation is a major feature in tissue inflammatory and atherosclerosis. The underlying molecular mechanism remains unclear.

Objective

This study aims to explore molecule targets and signaling which determinate immunological features in MC subsets.

Methods and Results

Blood Ly6C^high and Ly6C^low MC subsets from control and ApoE^-/- mice were isolated by flow cytometry sorting and subjected for bulk high-throughput RNA-sequencing. Intensive bioinformatic studies were performed by analyzing transcriptome through four pairs of comparisons: A) Ly6C^high vs Ly6C^low in control mice; B) Ly6C^high vs Ly6C^low in ApoE^-/- mice; C) ApoE^-/- Ly6C^high vs control Ly6C^high MC; D) ApoE^-/- Ly6C^low vs control Ly6C^low MC. A total of 80 canonical pathways and 16 enriched pathways were recognized by top-down analysis using IPA and GSEA software, and further used for overlapping analysis. Immunological features and signaling were assessed on four selected functional groups, including MHCII, immune checkpoint, cytokine, and transcription factor (TF). Among the total 14578 significantly differentially expressed (SDE) genes identified though above four comparison, 1051 TF and 348 immunological genes were discovered. SDE immunological genes were matched with corresponding upstream SDE TF by IPA upstream analysis. Fourteen potential transcriptional axes were recognized to modulate immunological features in the Ly6C MC subset. Based on an intensive literature search, we found that the identified SDE immune checkpoint genes in Ly6C^high MC are associated with pro-inflammatory/atherogenic balance function. Immune checkpoint genes GITR, CTLA4, and CD96 were upregulated in Ly6C^low MC from all mice and presented anti-inflammatory/atherogenic features. Six cytokine genes, including Ccl2, Tnfsf14, Il1rn, Cxcl10, Ccl9, and Cxcl2, were upregulated in Ly6C^high MC from all mice and associated with pro-inflammatory/atherogenic feature. Cytokine receptor gene Il12rb2, Il1r1, Il27ra, Il5ra, Ngfr, Ccr7, and Cxcr5 were upregulated in Ly6C^low MC from all mice and presented anti-inflammatory/atherogenic features. MHCII genes (H2-Oa, H2-DMb2, H2-Ob, H2-Eb2, H2-Eb1, H2-Aa, and Cd74) were elevated in Ly6C^low MC from all mice. ApoE^-/- augmented pro-atherogenic/inflammatory and antigen-presenting cells (APC) feature in both subsets due to elevated expression of cytokine genes (Cxcl11, Cntf, Il24, Xcl, Ccr5, Mpl, and Acvr2a) and MHCII gene (H2-Aa and H2-Ea-ps). Finally, we modeled immunological gene expression changes and functional implications in MC differentiation and adaptive immune response for MC subsets from control and ApoE^-/- mice.

Conclusions

Ly6C^high MC presented pro-inflammatory/atherogenic features and lower APC potential. Ly6C^low MC displayed anti-inflammatory/atherogenic features and higher APC potential. ApoE^-/- confers upon both subsets with augmented pro-atherogenic/inflammatory function and APC potential.

Clinical impact of echocardiography parameters and molecular biomarkers in heart failure: Correlation of ACE2 and MCP-1 polymorphisms with echocardiography parameters: A comparative study

Heart failure is still the leading cause of hospitalization in patients over 65 years of age and is defined as a multifactorial pathology which involves environmental factors and also genetic predispositions. The aim of the present study was to evaluate a possible correlation between single nucleotide polymorphisms (SNPs) of angiotensin converting enzyme 2 (ACE2) and monocyte chemoattractant protein-1 (MCP-1) genes and cardiac remodeling in Caucasian patients diagnosed with heart failure. Our comparative translational research study included 116 patients diagnosed with heart failure and was carried out in Cluj-Napoca, Romania between September 2017 and March 2019. Three SNPs, namely rs4646156, rs4646174 and rs1024611, were genotyped using a Taqman real-time PCR technique. Our results showed that carriers of the AA genotype for ACE2 rs4646156 had a significant dilatation of the left ventricle (LV) with signs of LV hypertrophy (LVH), while TT carriers had a significant left atrial dilatation. For ACE2 rs4646174, homozygotes for the C allele presented a dilated LV with signs of LVH with statistical significance and had a tendency towards a lower ejection fraction. MCP-1 rs1024611 AA variant carriers had a significant LVH in the dominant model. In conclusion, our study showed a strong association between echocardiographic parameters of cardiac remodeling and SNPs rs4646156, rs4646174 of ACE2 and rs1024611 of MCP-1.

Association study of MCP-1 promoter polymorphisms with the susceptibility and progression of sepsis

Previous studies have indicated that the monocyte chemo-attractant protein 1 (MCP-1), also referred to as C-C motif chemokine ligand 2 (CCL2), plays a significant role in the pathogenesis of sepsis, and this study investigated the clinical relevance of two MCP-1 gene polymorphisms on sepsis onset and progression. The Multiplex SNaPshot genotyping method was used to detect MCP-1 gene polymorphisms in the Chinese Han population (403 sepsis patients and 400 controls). MCP-1 mRNA expression levels were measured using real-time quantitative PCR, and enzyme-linked immunosorbent assays were used to analyze MCP-1, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) and interleukin-1 beta (IL-1β) plasma concentrations. The rs1024611 polymorphism analysis showed lower frequencies of minor homozygous genotype (AA) and allele (A) in sepsis patients compared to the healthy controls (19.4% vs. 31.5%, P = 0.0001 and 45.9% vs. 54.8%, P = 0.0004, respectively). And the frequencies of GG genotype and G allele were lower in sepsis patients compared to the controls (19.6% vs. 31.3%, P = 0.0002 and 46.0% vs. 54.5%, P = 0.0007, respectively). The rs1024611 AG/GG and rs2857656 GC/CC genotypes were both overrepresented in patients with severe sepsis (both P = 0.0005) and septic shock (P = 0.010 and P = 0.015, respectively) compared to the patients with mild sepsis. Moreover, among sepsis patients, the rs1024611 AG/GG and rs2857656 GC/CC carriers exhibited significant increases in expression levels of MCP-1 (P = 0.025), TNF-α (P = 0.034) and IL-6 (P = 0.043) compared with the rs1024611 AA or rs2857656 GG carriers. This study provides valuable clinical evidence that the MCP-1/CCL2 polymorphisms rs1024611 and rs2857656 are associated with sepsis susceptibility and development. We conclude that MCP-1/CCL2 plays a significant role in the pathogenesis of sepsis, which has potentially important therapeutic implications.

M1-like monocytes are a major immunological determinant of severity in previously healthy adults with life-threatening influenza

In each influenza season, a distinct group of young, otherwise healthy individuals with no risk factors succumbs to life-threatening infection. To better understand the cause for this, we analyzed a broad range of immune responses in blood from a unique cohort of patients, comprising previously healthy individuals hospitalized with and without respiratory failure during one influenza season, and infected with one specific influenza A strain. This analysis was compared with similarly hospitalized influenza patients with known risk factors (total of n = 60 patients recruited). We found a sustained increase in a specific subset of proinflammatory monocytes, with high TNF-α expression and an M1-like phenotype (independent of viral titers), in these previously healthy patients with severe disease. The relationship between M1-like monocytes and immunopathology was strengthened using murine models of influenza, in which severe infection generated using different models (including the high-pathogenicity H5N1 strain) was also accompanied by high levels of circulating M1-like monocytes. Additionally, a raised M1/M2 macrophage ratio in the lungs was observed. These studies identify a specific subtype of monocytes as a modifiable immunological determinant of disease severity in this subgroup of severely ill, previously healthy patients, offering potential novel therapeutic avenues.

In a cohort of influenza patients, previously healthy and young patients who succumbed to life-threatening disease were defined by high levels of circulating M1-like, TNF-α^hi monocytes.

CCR2 and CCR5 genes polymorphisms in women with cervical lesions from Pernambuco, Northeast Region of Brazil: a case-control study

Polymorphisms in chemokine receptors play an important role in the progression of cervical intraepithelial neoplasia (CIN) to cervical cancer (CC). Our study examined the association of CCR2-64I (rs1799864) andCCR5-Δ32 (rs333) polymorphisms with susceptibility to develop cervical lesion (CIN and CC) in a Brazilian population. The genotyping of 139 women with cervical lesions and 151 women without cervical lesions for the CCR2-64I and CCR5-Δ32 polymorphisms were performed using polymerase chain reaction-restriction fragment length polymorphism. The individuals carrying heterozygous or homozygous genotypes (GA+AA) for CCR2-64I polymorphisms seem to be at lower risk for cervical lesion [odds ratio (OR) = 0.37, p = 0.0008)]. The same was observed for the A allele (OR = 0.39, p = 0.0002), while no association was detected (p > 0.05) with CCR5-Δ32 polymorphism. Regarding the human papillomavirus (HPV) type, patients carrying the CCR2-64Ipolymorphism were protected against infection by HPV type 16 (OR = 0.35, p = 0.0184). In summary, our study showed a protective effect ofCCR2-64I rs1799864 polymorphism against the development of cervical lesions (CIN and CC) and in the susceptibility of HPV 16 infection.

Thicker Carotid Intima Media Thickness in Children with Monocyte Chemoattractant Protein-1: A-2138T and A-2464G Mutation

Carotid intima media thickness (CIMT) is clearly associated with atherosclerosis. Studies in ischemic stroke patients reveal that there is a significant association between CIMT with monocyte chemoattractant protein-1 (MCP-1) and osteopontin (OPN) promoter polymorphism. This research aims to explain the effect of MCP-1 and OPN promoter polymorphism toward CIMT changes identified in Javanese Indonesian children. Subjects were 54 children: 27 were from parents with ischemic stroke (cases), and 27 were from healthy parents (controlled). The CIMT was examined by utilizing high resolution B-mode ultrasound. Physical examination and genotyping analysis of MCP-1 promoter were conducted by employing PCR method. Research results indicate that two polymorphisms were obtained, that is, A-2138T and G-2464A, respectively. A-2138T polymorphism was found in 5% of case children and in 14.3% of controlled children. G-2464A polymorphism was found in 5% of case children. CIMT of case children was significantly different from that of controlled children (0.61 ± 0.012 mm versus, 0.52 ± 0.015 mm, P = 0.021). Subjects with MCP-1 promoter polymorphism have 1.471 times higher tendency to have thicker CIMT than subjects with no polymorphism in MCP1 promoter. OPN promoter T-66G was also studied but it did not indicate occurrence of polymorphism in samples.

Genetic diversity and linkage disequilibrium in the chemokine receptor CCR2-CCR5 region among individuals and populations

BACKGROUND

Chemokine receptors CCR2 and CCR5 play a key role in immune and inflammatory responses and have been associated with several diseases, including AIDS. In order to comprehend health disparities it is important to understand the nature of genetic variation in specific genes of interest in different populations. Current studies of the CCR2 and CCR5 receptor genes are primarily focused on the CCR5-Δ32, and CCR2-V64I SNPs.

METHODS

Sanger sequencing was used to sequence the regions containing 16 SNPs in the adjacent CCR2 and CCR5 genes (including CCR5-Δ32, and CCR2-V64I) in 249 subjects of African, European and Hispanic ancestry. Linkage disequilibrium (LD) and haplotypes were determined using Haploview.

RESULTS

The data revealed large differences in allele frequencies of several SNPs and LD patterns among the ethnic groups, including SNPs that were restricted to Africans or Europeans. Seven known CCR5 haplotypes and six novel CCR2 haplotypes were identified. A rare case of an HIV+ subject with the CCR5-Δ32/Δ32 was identified.

CONCLUSIONS

These data demonstrate a LD between CCR2 and CCR5 at several loci and provide new information about CCR2 that contributes to our understanding of its population-specific genetic variability. The data indicate that in addition to CCR5-Δ32 and CCR2-V64I, other SNPs and haplotypes may be important genetic determinants of disease and should be investigated.

The synergy of -260T T CD14 and -308GG TNF-α genotypes in survival of critically ill patients

Literature suggests that the analysis of several polymorphic genetic markers is more informative than the analysis of a single polymorphism. In this study, we tested whether the shared inheritance of TLR2 and TLR4 and TNF-α allelic variants may act in synergy with -260C>T CD14 SNP on the outcome from critical conditions. We monitored 524 critically ill patients from South Brazilian, daily from the ICU admission to their discharge from hospital, or death. Our results revealed that TLR2, TLR4 or TNF-α SNPs alone did not show a significant role in the outcome from critical illness. However, when we performed a combined analysis with the CD14 inheritance, we detected a significant higher survivor rate in -260TT CD14/-308GG TNF-α individuals (P = 0.037). In the adjusted analysis including the main clinical predictors to mortality, we observed that -260TT/-308GG double-genotype was a significant protective factor towards survival (P = 0.046). An increased probability for survival of -260TT/-308GG was also observed by 'pathway genetic load' analysis (unweighted: P = 0.041; weighted: P = 0.036). When we applied a hazard function analysis with the -260TT/-308GG variable as a discriminating factor, -260TT/-308GG patients group had, in fact, a higher survivor rate (P = 0.024). Connected to the beneficial effect of -260TT CD14, the -308GG TNF-α genotype was protective against the reported over expression of TNF-α caused by -308A rare allele. Results support the hypothesis that the interaction between -260C>T CD14 and -308G>A TNF-α functional SNPs may be synergistically influencing the outcome of critically ill patients.

Association analysis of USF1 gene polymorphisms and total unstable carotid plaque area in atherosclerotic stroke patients

Polymorphisms of the upstream stimulatory factor 1 (USF1) have been associated with carotid artery intima-media thickness and coronary atherosclerotic lesions. Unstable carotid plaque is an atherosclerotic change of vascular morphology that has been correlated with cerebrovascular ischemic symptoms. Associations of three single nucleotide polymorphisms of the USF1 gene with total unstable carotid plaque area (CPA) were investigated in Chinese atherosclerotic stroke patients. We recruited 668 atherosclerotic stroke patients and 602 controls. Total unstable CPA values were measured by ultrasound. Genotypes were analyzed using polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) or mismatched PCR-RFLP. A significant difference in total unstable CPA was found for rs2516838 and rs2516839 genotypes (P = 0.039 and 0.046, respectively) in atherosclerotic stroke patients with unstable carotid plaque. Furthermore, in multiple logistic regression analysis adjusted by age, sex, BMI, hypertension, smoking status, glucose, total cholesterol, triglycerides, high-density lipoprotein-cholesterols, low-density lipoprotein-cholesterols and high-sensitivity C-reactive protein, significant associations were seen between the total unstable CPA values and genotypes of the rs2516838 or the rs2516839 in these patients. The rare allele C of rs2516838 or rare allele A of rs2516839 could predict relative low total unstable CPA values. The rs2516838 and rs2516839 polymorphisms of USF1 influence total unstable CPA in atherosclerotic stroke patients, which might be new markers to predict the risk of recurrence for this disease.

The rs1024611 regulatory region polymorphism is associated with CCL2 allelic expression imbalance

CC chemokine ligand 2 (CCL2) is the most potent monocyte chemoattractant and inter-individual differences in its expression level have been associated with genetic variants mapping to the cis-regulatory regions of the gene. An A to G polymorphism in the CCL2 enhancer region at position -2578 (rs1024611; A>G), was found in most studies to be associated with higher serum CCL2 levels and increased susceptibility to a variety of diseases such as HIV-1 associated neurological disorders, tuberculosis, and atherosclerosis. However, the precise mechanism by which rs1024611influences CCL2 expression is not known. To address this knowledge gap, we tested the hypothesis that rs1024611G polymorphism is associated with allelic expression imbalance (AEI) of CCL2. We used haplotype analysis and identified a transcribed SNP in the 3'UTR (rs13900; C>T) can serve as a proxy for the rs1024611 and demonstrated that the rs1024611G allele displayed a perfect linkage disequilibrium with rs13900T allele. Allele-specific transcript quantification in lipopolysaccharide treated PBMCs obtained from heterozygous donors showed that rs13900T allele were expressed at higher levels when compared to rs13900C allele in all the donors examined suggesting that CCL2 is subjected to AEI and that that the allele containing rs1024611G is preferentially transcribed. We also found that AEI of CCL2 is a stable trait and could be detected in newly synthesized RNA. In contrast to these in vivo findings, in vitro assays with haplotype-specific reporter constructs indicated that the haplotype bearing rs1024611G had a lower or similar transcriptional activity when compared to the haplotype containing rs1024611A. This discordance between the in vivo and in vitro expression studies suggests that the CCL2 regulatory region polymorphisms may be functioning in a complex and context-dependent manner. In summary, our studies provide strong functional evidence and a rational explanation for the phenotypic effects of the CCL2 rs1024611G allele.

Association of inflammatory gene polymorphisms with ischemic stroke in a Chinese Han population

BACKGROUND

Inflammatory mechanisms are important in stroke risk, and genetic variations in components of the inflammatory response have been implicated as risk factors for stroke. We tested the inflammatory gene polymorphisms and their association with ischemic stroke in a Chinese Han population.

METHODS

A total of 1,124 ischemic stroke cases and 1,163 controls were genotyped with inflammatory panel strips containing 51 selected inflammatory gene polymorphisms from 35 candidate genes. We tested the genotype-stroke association with logistic regression model.

RESULTS

We found two single nucleotide polymorphisms (SNPs) in CCL11 were associated with ischemic stroke. After adjusting for multiple testing using false discovery rate (FDR) with a 0.20 cut-off point, CCL11 rs4795895 remained statistically significant. We further stratified the study population by their hypertension status. In the hypertensive group, CCR2 rs1799864, CCR5 rs1799987 and CCL11 rs4795895 were nominally associated with increased risk of stroke. In the non-hypertensive group, CCL11 rs3744508, LTC4S rs730012, FCER1B rs569108, TGFB1 rs1800469, LTA rs909253 and CCL11 rs4795895 were associated with ischemic stroke. After correction for multiple testing, CCR2 rs1799864 and CCR5 rs1799987 remained significant in the hypertensive group, and CCL11 rs3744508, LTC4S rs730012, FCER1B rs569108, TGFB1 rs1800469, LTA rs909253 remained significant in the non-hypertensive group.

CONCLUSIONS

Our results indicate that inflammatory genetic variants are associated with increased risk of ischemic stroke in a Chinese Han population, particularly in non-hypertensive individuals.

Monocyte chemoattractant protein-1 is associated with silent cerebral infarction in patients on haemodialysis

BACKGROUND

In patients with chronic renal failure undergoing haemodialysis (HD), silent cerebral infarctions (SCI) are associated with high mortality. Levels of monocyte chemoattractant protein-1 (MCP-1) increase with renal dysfunction and may be a novel predictor for cerebrovascular events. We tested the hypothesis that increased MCP-1 concentration correlate with the occurrence of SCI in HD patients.

METHODS

Using cranial magnetic resonance imaging (MRI) findings, 52 Japanese patients undergoing HD were divided into two groups: with SCI (61 ± 7 years, mean ± SD, n= 28) and without SCI (60 ± 6 years, n= 24). The gender, metabolic profiles and MCP-1 concentration were compared between the two groups.

RESULTS

The level of MCP-1 was higher in the with-SCI group than in the without-SCI group (P < 0.0001). The proportion of smokers was higher in the with-SCI group (P < 0.05) than in the without-SCI group. Plasma level of high-density lipoprotein cholesterol was lower, while uric acid level was higher, in the with-SCI group (P < 0.05 and P < 0.05 respectively) compared to the without-SCI group. Multiple logistic regression analysis identified MCP-1 level as being significantly associated with the presence of SCI (odds ratio 1.48, 95% confidence interval = 1.10-5.75, P < 0.0001).

CONCLUSIONS

This study indicates that patients with chronic renal failure who are maintained on HD exhibit an increased prevalence of SCI, and that MCP-1 is significantly associated with the presence of SCI in HD patients.

Biomarker discovery in serum from patients with carotid atherosclerosis

BACKGROUND

Blood-based biomarkers of atherosclerosis have been used to identify patients at high risk for developing stroke. We hypothesized that patients with carotid artery disease would have a distinctive proteomic signature in blood as compared to a healthy control population without carotid artery disease. In order to discover protein biomarkers associated with increased atherosclerotic risk, we used two different strategies to identify biomarkers from patients with clinically defined atherosclerosis who were undergoing endarterectomy for atherosclerotic carotid artery disease. These patients were compared with healthy matched controls.

METHODS

Serum was obtained from patients undergoing endarterectomy (EA; n = 38) and compared to a group of age-matched healthy controls (n = 40). Serum was fractionated using anion exchange chromatography and three different surface-enhanced laser desorption/ionization (SELDI) chip surfaces and then evaluated with mass spectrometry (MS) and two-dimensional difference gel electrophoresis (2D-DIGE).

RESULTS

A random forest (RF) analysis of the SELDI-MS protein peak data distinguished these two groups with 69.2% sensitivity and 73.2% specificity. Four unique SELDI peaks (4.2, 4.4, 16.7 and 28 kDa, all p< 0.01) showed the greatest influence in the RF model. The EA patients with a history of prior clinical atherosclerotic plaque rupture manifested as either stroke or transient ischemic attack (symptomatic; n = 16) were compared to patients with carotid atherosclerosis but no clinical evidence of plaque rupture (asymptomatic; n = 22). Analysis of the SELDI spectra did not separate these two patient subgroups. A subgroup analysis using 2D-DIGE images obtained from albumin-depleted serum comparing symptomatic (n = 10) to asymptomatic EA patients (n = 10) found 4 proteins that were differentially expressed (p < 0.01) in the symptomatic patients. These proteins were identified as α(1)-antitrypsin, haptoglobin and vitamin D binding protein that were downregulated and α(2)-glycoprotein precursor that was upregulated in the symptomatic EA group.

CONCLUSIONS

SELDI-MS data analysis of fractionated serum suggests that a distinct protein signature exists in patients with carotid atherosclerosis compared to age-matched healthy controls. Identification of 4 proteins in a subset of patients with symptomatic and asymptomatic carotid atherosclerosis suggests that these and other protein biomarkers may assist in identifying high-risk patients with carotid atherosclerosis.

MCP-1 and CCR2 gene variants and the risk for osteoporosis and osteopenia

AIM

In this study, we investigated whether monocyte chemotactic protein 1 (MCP-1) and CC chemokine receptor 2 (CCR2) gene polymorphisms account for an increased risk of osteoporosis or osteopenia.

METHODS

Three hundred three postmenopausal women, 80 osteoporotic, 123 osteopenic, and 100 unrelated age-matched healthy controls, were included in the study. Genotyping of MCP-1 A2518G and CCR2 V64I gene polymorphisms were detected by PCR-RFLP.

RESULTS

We, for the first time, demonstrated the positive association of MCP-1 GG, CCR2 Val/Ile, and CCR2 Val+ genotype with osteoporosis risk. However, CCR2 Ile/Ile genotype frequencies were high in the control group compared with those of the patients with osteoporosis and osteopenia. Haplotype analysis confirmed the association of MCP-1/CCR2 gene variants with osteopenia and revealed that the frequency of MCP-1 A:CCR2 Val haplotype was significantly higher in patients when compared with controls.

CONCLUSIONS

In conclusion, our findings have suggested that MCP-1 and CCR2 gene variants were risk factors for osteoporosis and osteopenia.

BRAP Activates Inflammatory Cascades and Increases the Risk for Carotid Atherosclerosis

The BRCA-1 associated protein gene (BRAP) was recently identified as a susceptibility gene for myocardial infarction (MI). In the present study we aimed to decipher the association between the BRAP polymorphism and carotid atherosclerosis and the mechanism underlying its proatherogenic effect. A total of 1749 stroke/MI-free volunteers received carotid ultrasonic examinations for the measurement of intima-medial thickness (IMT) and plaque. The promoter polymorphism rs11066001 was selected because it affects the transcription of BRAP. We found that the GG genotype was associated with a 1.58-fold increased risk for having at least one plaque compared to carrying the A allele (P = 0.021). When subjects were divided by the cutoff value of IMT above the mean plus 1 standard deviation, there was an overrepresentation of the GG genotype in the subjects with thicker IMT (P = 0.004). The expression of BRAP increased significantly when human aortic smooth muscle cells (HASMCs) were treated with lipopolysaccharide (LPS). HASMCs were transfected with small interfering RNA against BRAP or scrambled sequences before treatment with LPS. Knockdown of BRAP led to attenuated HASMC proliferation and reduced secretion of monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 (IL-8) in response to LPS. Downregulation of BRAP did not affect the protein levels of nuclear factor-κB (NF-κB), but prohibited its nuclear translocation. Coimmunoprecipitation experiments confirmed an interaction between BRAP and the two major components of the IKK signalosome, IκBβ and IKKβ. Collectively, BRAP conferred a risk for carotid plaque and IMT. Inflammatory stimuli upregulated BRAP expression, and BRAP activated inflammatory cascades by regulating NF-κB nuclear translocation.

Association of an INSIG2 obesity allele with cardiovascular phenotypes is gender and age dependent

Background

The INSIG2 gene has been implicated in cholesterol metabolism and a single nucleotide polymorphism (SNP) near INSIG2 has been shown to be associated with obesity. We sought to determine the relationship of the INSIG2 SNP to cardiovascular disease (CVD) related phenotypes.

Methods and Results

Nine hundred forty six patients undergoing percutaneous coronary intervention (PCI) in wave 5 of the multicenter NHLBI Dynamic Registry were genotyped using RT-PCR/TaqMan/allelic discrimination for the rs7566605 SNP near the INSIG2 gene. Clinical variables analyzed include demographics, medical history, and procedural details. The prevalence of peripheral vascular disease (PVD) was significantly higher in older men (≥65 years) who were either homozygous or carriers of the obesity/lipid risk allele ("C") compared to non-carriers (odds ratio 3.4, p = 0.013) using a logistic regression model incorporating history of hypercholesterolemia, history of hypertension, cerebrovascular disease, history of diabetes, and BMI. A similar relationship with cerebrovascular disease was found in older (>65) women (odds ratio 3.4, p = 0.013). The INSIG2 SNP was not associated with BMI, nor with other clinical variables.

Conclusion

Age and gender may influence the association of the INSIG2 obesity SNP with PVD and cerebrovascular disease in patients with pre-existing CVD.

CCR2-V64I polymorphism is associated with increased risk of cervical cancer but not with HPV infection or pre-cancerous lesions in African women

BACKGROUND

Cervical cancer, caused by specific oncogenic types of human papillomavirus (HPV), is the second most common cancer in women worldwide. A large number of young sexually active women get infected by HPV but only a small fraction of them have persistent infection and develop cervical cancer pointing to co- factors including host genetics that might play a role in outcome of the HPV infection. This study investigated the role of CCR2-V64I polymorphism in cervical cancer, pre-cancers and HPV infection in South African women resident in Western Cape. CCR2-V64I polymorphism has been previously reported to influence the progression to cervical cancer in some populations and has also been associated with decreased progression from HIV infection to AIDS.

METHODS

Genotyping for CCR2-V64I was done by PCR-SSP in a case-control study of 446 women (106 black African and 340 mixed-ancestry) with histologically confirmed invasive cervical cancer and 1432 controls (322 black African and 1110 mixed-ancestry) group-matched (1:3) by age, ethnicity and domicile status. In the control women HPV was detected using the Digene Hybrid Capture II test and cervical disease was detected by cervical cytology.

RESULTS

The CCR2-64I variant was significantly associated with cervical cancer when cases were compared to the control group (P = 0.001). Further analysis comparing selected groups within the controls showed that individuals with abnormal cytology and high grade squamous intraepitleial neoplasia (HSIL) did not have this association when compared to women with normal cytology. HPV infection also showed no association with CCR2-64I variant. Comparing SIL positive controls with the cases showed a significant association of CCR2-64I variant (P = 0.001) with cervical cancer.

CONCLUSIONS

This is the first study of the role of CCR2-V64I polymorphism in cervical cancer in an African population. Our results show that CCR2-64I variant is associated with the risk of cervical cancer but does not affect the susceptibility to HPV infection or HSIL in South African women of black and mixed-ancestry origin. This result implies that the role of CCR2 is important in invasive cancer of the cervix but not in HPV infection or in the development of pre-cancers.