A CCR2-V64I polymorphism affects stability of CCR2A isoform

Association between chemokine genes polymorphisms and susceptibility to Parkinson's disease: a meta-analysis and systematic review

OBJECTIVE

This study aimed to investigate the potential association between polymorphisms in monocyte chemoattractant protein-1 (MCP-1), chemokine receptor type 2 (CCR2), type 5 (CCR5), regulated on activation, normal T cell expressed, and secreted (RANTES) and susceptibility to Parkinson's disease (PD).

METHODS

The MEDLINE, EMBASE, and Web of Science databases were searched for relevant articles, and a meta-analysis was conducted to assess the associations between the MCP-1 -2518 G/A, CCR2 V64I, CCR5-Δ32, RANTES - 405 G/A, -28 G/A polymorphisms and the risk of PD.

RESULTS

Six studies with 1,416 patients with PD and 1,715 controls that met the inclusion criteria were identified. Meta-analysis of all study participants demonstrated no association between PD and the MCP-1 -2518 G allele (odds ratio [OR] = 1.089, 95% confidence interval [CI] = 0.980-1.211, p = 0.114). Stratification by ethnicity indicated no association between the MCP-1 -2518 G allele and PD in the European and Asian populations. Meta-analysis demonstrated no association between PD and the MCP-1-2518 A/G polymorphism in recessive and dominant models and homozygote contrast. However, meta-analysis revealed a significant association between the risk of PD and the CCR2-V64I AA + GG genotype in all study participants (OR = 0.418, 95% CI = 0.232-0.753, p = 0.004). Stratification based on ethnicity validated this association between the CCR2-V64I AA + GG genotype and PD in the Asian population (OR = 0.460, 95% CI = 0.243-0.870, p = 0.017), but not in European populations. Analysis using the homozygous contrast model revealed the same pattern for the CCR2-V64I AA + GG genotype. Meta-analysis revealed no association between the CCR5-Δ32 allele and the risk of PD (OR = 0.972, 95% CI = 0.377-2.501, p = 0.952). Moreover, the meta-analysis demonstrated no allelic association between RANTES - 405 G/A and - 28 G/A polymorphisms and the risk of PD.

CONCLUSIONS

Our meta-analysis showed that the CCR2 V64I polymorphism is associated with PD, especially in Asian populations.

Significant association of MCP1 rs1024611 and CCR2 rs1799864 polymorphisms with colorectal cancer and liver metastases susceptibility and aggressiveness: A case-control study

BACKGROUND

The MCP-1/CCR2 axis is one of the major chemokine signaling pathways that play a crucial role in the tumor microenvironment and has been involved in triggering various tumor progression mechanisms, such as increasing the immunosuppressive cells recruitment and promoting tumor cell proliferation and invasiveness.

AIM

The current study investigated the association of MCP1 (rs1024611) and CCR2 (rs1799864) genes variants with the risk as well as prognosis of colorectal cancer (CRC) and colorectal liver metastases (CRLM).

SUBJECTS AND METHODS

A retrospective cohort study involved 408 patients (284 CRC and 124 CRLM), and 284 healthy control was conducted. Genotyping of selected polymorphisms was performed by PCR-RFLP assays and confirmed by microchip and capillary electrophoresis.

RESULTS

The results highlighted a positive association between MCP1 rs1024611 (non-AA) and CCR2 rs1799864 (GA) genotypes with increased CRC and CRLM risk. Correlation between SNPs and clinicopathological characteristics revealed a positive association between MCP1 rs1024611 and CCR2 rs1799864 (dominant model) and CRC poor prognosis features. Kaplan-Meier survival analysis revealed a significant association between MCP1 rs1024611 non-AA carriers and decreased survival rate. Neoadjuvant treatment showed an improvement in CRC and CRLM survival rates among carriers of MCP1 and CCR2 wild-type genotype. FOLFIRI chemotherapy exhibits reduced survival rates for patients who carried mutated genotypes of MCP1 and CCR2 polymorphisms.

CONCLUSION

Considering our results, we suggest That both MCP1 and CCR2 polymorphisms may constitute independent factors for CRC and CRLM occurrence and can be helpful targets for an efficient therapeutic approach.

The impact of MCP1-2518A/G and CCR2-V64I genetic polymorphisms in Egyptian sickle cell disease patients

BACKGROUND

Sickle cell disease (SCD) is an inherited genetic disorders of hemoglobin that causes multisystem morbidity. The pathophysiology of SCD is complex and includes HbS polymerization/sickling, hemolysis, endothelial dysfunction and inflammation. Chemokines are proteins playing an important role in the inflammation process and could be involved the context of pro-inflammatory SCD. Some chemokine polymorphism were found to be associated with clinical complication in SCD.

AIM OF THE STUDY

Was to explore the frequency and the possible effect of Monocyte Chemo-attractant Protein 1-2518A/G (MCP1-2518A/G) and Chemokine Receptor 2-V64I (CCR2-V64I) genetic polymorphisms on clinical and laboratory disease-related variables in Egyptian Sickle cell disease patients.

PATIENTS AND METHODS

Genotyping of the two genes were performed by PCR-RFLP technique for 80 SCD patients as well as 50 healthy control group.

RESULTS

The study revealed that the MCP1-2518 polymorphic genotypes (AG & GG) showed no statistically significant difference in the distribution of the polymorphic genotypes between SCD patients and the controls (p = 0.164). While a significantly higher frequency of the mutant variants CCR2-V64I GA/AA among SCD patients than the control subjects were found (p = 0.032). Regarding the clinic-pathological features, the frequency of recurrent infections, vaso-occlusive crisis, severe vaso-occlusive crisis and number of hospitalization/year were higher in patients harbouring the MCP1-2518A/G and CCR2-V64I polymorphic genotypes than the wild genotype, and gall bladder complications were higher in MCP1-2518 G allele patients, whereas surgical splenectomy were higher in CCR2-V64I A allele patients (p < 0.05).

IN CONCLUSION

MCP1-2518A/G and CCR2-V64I genetic polymorphisms may influence the clinical severity of sickle cell disease.

Variations in cag pathogenicity island genes of Helicobacter pylori from Latin American groups may influence neoplastic progression to gastric cancer

Helicobacter pylori (HP) colonizes the human stomach and induces acute gastritis, peptic ulcer disease, atrophic gastritis, and gastric adenocarcinoma. Increased virulence in HP isolates derives from harboring the cag (cytotoxin-associated genes) pathogenicity island (cagPAI). We analyzed the microvariants in cagPAI genes with the hypothesis that they may play an important role in determining HP virulence. We tested DNAs from cagA positive patients HP isolates; a total of 74 patients with chronic gastritis (CG, N = 37), intestinal metaplasia (IM, N = 21) or gastric cancer (GC, N = 16) from Mexico and Colombia. We selected 520 non-synonymous variants with at least 7.5% frequency in the original sequence outputs or with a minimum of 5 isolates with minor allele. After adjustment for multiple comparisons, no variants were statistically significantly associated with IM or GC. However, 19 non-synonymous showed conventional P-values < 0.05 comparing the frequency of the alleles between the isolates from subjects with gastritis and isolates from subjects with IM or GC; 12 of these showed a significant correlation with the severity of the disease. The present study revealed that several cagPAI genes from Latin American Western HP strains contains a number of non-synonymous variants in relatively high frequencies which could influence on the clinical outcome. However, none of the associations remained statistically significant after adjustment for multiple comparison.

The role of GPCRs in bone diseases and dysfunctions

The superfamily of G protein-coupled receptors (GPCRs) contains immense structural and functional diversity and mediates a myriad of biological processes upon activation by various extracellular signals. Critical roles of GPCRs have been established in bone development, remodeling, and disease. Multiple human GPCR mutations impair bone development or metabolism, resulting in osteopathologies. Here we summarize the disease phenotypes and dysfunctions caused by GPCR gene mutations in humans as well as by deletion in animals. To date, 92 receptors (5 glutamate family, 67 rhodopsin family, 5 adhesion, 4 frizzled/taste2 family, 5 secretin family, and 6 other 7TM receptors) have been associated with bone diseases and dysfunctions (36 in humans and 72 in animals). By analyzing data from these 92 GPCRs, we found that mutation or deletion of different individual GPCRs could induce similar bone diseases or dysfunctions, and the same individual GPCR mutation or deletion could induce different bone diseases or dysfunctions in different populations or animal models. Data from human diseases or dysfunctions identified 19 genes whose mutation was associated with human BMD: 9 genes each for human height and osteoporosis; 4 genes each for human osteoarthritis (OA) and fracture risk; and 2 genes each for adolescent idiopathic scoliosis (AIS), periodontitis, osteosarcoma growth, and tooth development. Reports from gene knockout animals found 40 GPCRs whose deficiency reduced bone mass, while deficiency of 22 GPCRs increased bone mass and BMD; deficiency of 8 GPCRs reduced body length, while 5 mice had reduced femur size upon GPCR deletion. Furthermore, deficiency in 6 GPCRs induced osteoporosis; 4 induced osteoarthritis; 3 delayed fracture healing; 3 reduced arthritis severity; and reduced bone strength, increased bone strength, and increased cortical thickness were each observed in 2 GPCR-deficiency models. The ever-expanding number of GPCR mutation-associated diseases warrants accelerated molecular analysis, population studies, and investigation of phenotype correlation with SNPs to elucidate GPCR function in human diseases.

Association of Diverse Genotypes and Phenotypes of Immune Cells and Immunoglobulins With the Course of HIV-1 Infection

Disease progression among HIV-1-infected individuals varies widely, but the mechanisms underlying this variability remains unknown. Distinct disease outcomes are the consequences of many factors working in concert, including innate and adaptive immune responses, cell-mediated and humoral immunity, and both genetic and phenotypic factors. Current data suggest that these multifaceted aspects in infected individuals should be considered as a whole, rather than as separate unique elements, and that analyses must be performed in greater detail in order to meet the requirements of personalized medicine and guide optimal vaccine design. However, the wide adoption of antiretroviral therapy (ART) influences the implementation of systematic analyses of the HIV-1-infected population. Consequently, fewer data will be available for acquisition in the future, preventing the comprehensive investigations required to elucidate the underpinnings of variability in disease outcome. This review seeks to recapitulate the distinct genotypic and phenotypic features of the immune system, focusing in particular on comparing the surface proteins of immune cells among individuals with different HIV infection outcomes.

CCR5 Revisited: How Mechanisms of HIV Entry Govern AIDS Pathogenesis

The chemokine receptor CCR5 has been the focus of intensive studies since its role as a coreceptor for HIV entry was discovered in 1996. These studies lead to the development of small molecular drugs targeting CCR5, with maraviroc becoming in 2007 the first clinically approved chemokine receptor inhibitor. More recently, the apparent HIV cure in a patient transplanted with hematopoietic stem cells devoid of functional CCR5 rekindled the interest for inactivating CCR5 through gene therapy and pharmacological approaches. Fundamental research on CCR5 has also been boosted by key advances in the field of G-protein coupled receptor research, with the realization that CCR5 adopts a variety of conformations, and that only a subset of these conformations may be targeted by chemokine ligands. In addition, recent genetic and pathogenesis studies have emphasized the central role of CCR5 expression levels in determining the risk of HIV and SIV acquisition and disease progression. In this article, we propose to review the key properties of CCR5 that account for its central role in HIV pathogenesis, with a focus on mechanisms that regulate CCR5 expression, conformation, and interaction with HIV envelope glycoproteins.

Monocyte Chemoattractant Protein-1 in Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis: Biomarker Potential and Association with Polymorphisms in the MCP-1 and the CC Chemokine Receptor-2 Gene

Antineutrophil cytoplasmic autoantibody- (ANCA-) associated vasculitis (AAV) are relapsing-remitting disorders with unpredictable prognosis. There is a need of biomarkers for distinguishing which patients will have a more severe outcome and also for predicting relapses in disease activity. This study confirms the previous results of urinary MCP-1 (uMCP-1) as a prognostic marker and explores its potential as a marker of disease activity. Method. 114 patients with AAV were followed regularly between 2002 and 2011 at Skåne University Hospital. Urine samples, blood samples, and clinical status were registered. The urine samples were analyzed in an in-house-developed ELISA. PCR-RLFP was used to analyze the MCP-1 and CCR2 genes. Results. Patients with severe prognosis had significantly higher levels of uMCP-1 compared to patients with nonsevere prognosis and healthy controls. Patients with renal damage had higher levels compared to patients who did not have renal damage. There was also a tendency of higher uMCP-1 levels in active disease as compared to remission. AA in the -2518 position in the MCP-1 gene was associated with a more severe outcome compared to the A/G or the G/G genotype. The A/A genotype were also associated with higher levels of uMCP-1. No significant associations were seen for the CCR2-V64I. Conclusion. This study confirmed the connection between high uMCP-1 levels and poor prognosis and also disease activity. It also suggests an association of the A/A genotype at position -2518 in the MCP-1 gene and poor prognosis in AAV. uMCP-1 is clearly a candidate biomarker of potential clinical value. The A/A genotype association needs further evaluation.

Plasma MCP-1 and Cognitive Decline in Patients with Alzheimer's Disease and Mild Cognitive Impairment: A Two-year Follow-up Study

Monocyte chemoattractant protein-1 (MCP-1, also known as chemokine CCL2) is a vital chemokine that mediates inflammation in Alzheimer’s disease (AD). We analyzed the associations between the baseline plasma MCP-1 level, longitudinal cognitive changes, and genetic effects of CCL2 rs1024611 and its receptor, CC-chemokine receptor 2 (CCR2) rs1799864, in AD. In total, 310 AD patients and 66 mild cognitive impairment (MCI) patients were followed for 2 years, and 120 controls were recruited at baseline for comparison. After adjusting for covariates using one-way analysis of covariance, AD patients had higher plasma MCP-1 levels compared with MCI patients and controls, and severe AD patients had the highest levels. After adjusting for covariates using generalized estimating equation analysis, the results showed that the baseline MCP-1 level was significantly correlated with changes in the two-year Mini-Mental Status Examination (p = 0.046). The A allele of CCR2 rs1799864 was associated with a higher MCP-1 level in AD and MCI patients. In conclusion, plasma MCP-1 might reflect the risk and disease course of AD. A higher plasma MCP-1 level is associated with greater severity and faster cognitive decline. Additionally, the CCR2 polymorphism may play a role in the regulation of MCP-1/CCR2 signaling in AD.

Immunogenetics of prostate cancer: a still unexplored field of study

The immune system is a double-edged sword with regard to the prostate cancer (PCa) battle. Immunogenetics, the study of the potential role of immune-related polymorphisms, is taking its first steps in the treatment of this malignancy. This review summarizes the most recent papers addressing the potential of immunogenetics in PCa, reporting immune-related polymorphisms associated with tumor aggressiveness, treatment toxicity and patients' prognosis. With some peculiarities, RNASEL, IL-6, IL-10, IL-1β and MMP7 have arisen as the most significant biomarkers in PCa treatment and management, having a potential clinical role. Validation prospective clinical studies are required to translate immunogenetics into precision treatment of PCa.

The association of genetic variants in chemokine genes with the risk of psoriasis vulgaris in Chinese population: A case-control study

This study aimed to investigate the influence of polymorphisms in chemokine genes, including MCP1, CCR2, and CCR5 with psoriasis vulgaris (PV) risk in a Chinese population.The genotyping of studied polymorphisms through polymerase chain reaction (PCR) and sequencing was conducted in 142 PV patients and 147 healthy controls. The genotype distribution of the polymorphisms in the control group was checked to determine whether it conformed to Hardy-Weinberg equilibrium (HWE). The genotype and allele frequencies were compared between PV patients and the healthy controls using Chi-square test. Odds ratio (OR) with 95% confidence interval (95% CI) was calculated to assess the relative risk of PV related to genetic variants.CCR2 rs1799864 polymorphism was associated with significantly elevated risk of PV (AA+AG vs GG: OR = 1.62, 95% CI = 1.02-2.59; A vs G: OR = 1.48, 95% CI = 1.02-2.16). In the meanwhile, CCR5 rs1800024 polymorphism also exhibited significant differences in genotype and allele distribution (P < .05), demonstrating its promoting effect on the risk of PV under heterozygous model (OR = 1.73, 95% CI = 1.06-2.82), dominance model (OR = 1.83, 95% CI = 1.14-2.94), and allele model (OR = 1.68, 95% CI = 1.13-2.48).CCR2 rs1799864 and CCR5 rs1800024 polymorphisms may function as independent risk factors for PV in Chinese population.

Significance of CCL2, CCL5 and CCR2 polymorphisms for adverse prognosis of Japanese encephalitis from an endemic population of India

Japanese encephalitis (JE) is a major contributor for viral encephalitis in Asia. Vaccination programme has limited success for largely populated JE endemic countries like India and disease exposure is unavoidable. Involvement of chemokines and its co-receptors for adverse prognosis of JE have been documented both in vitro and in vivo. Identification of the genetic predisposing factor for JE infection in humans is crucial but not yet established. Therefore, we investigated the association of single nucleotide polymorphisms (SNPs) in chemokines (CCL2 and CCL5) and its co-receptors (CCR2 and CCR5) with their protein level for JE. The study enrolled 87 symptomatic JE cases (mild: severe = 24:63) and 94 asymptomatic controls. Our study demonstrated that CCL2 (rs1024611G), CCL5 (rs2280788G) and CCR2 (rs1799864A) significantly associated with JE (Odds ratio = 1.63, 2.95 and 2.62, respectively and P = 0.045, P = 0.05 and P = 0.0006, respectively). The study revealed that rs1024611G allele was associated with elevated level of CCL2. CCL5 elevation associated with JE mortality having a Cox proportional hazard of 1.004 (P = 0.033). In conclusion, SNPs of chemokine viz. CCL2 (rs1024611G) and its receptor CCR2 (rs1799864A) significantly associated with JE which may serve as possible genetic predisposing factor and CCL5 protein level may act as marker for disease survival.

Association of CCR2 (+190 G/A) Gene Variants and Ovarian Cancer Severity

AIM

Chemokines and their receptors play an important role in tumor progression. In the current study, we aimed to determine the association between the CCR2 gene (+190 G/A) polymorphism and ovarian cancer severity.

METHODS

CCR2 (+190 G/A) genotyping was performed using real-time polymerase chain reaction for DNA isolated from blood samples from a cohort of patients with ovarian cancer (n = 44) and a control group (n = 45).

RESULTS

The CCR2 (+190 G/A) GG genotype frequencies for patients were significantly higher in the stage III-IV cancer group (p = 0.036), and A allele carriers were significantly higher in the stage I-II ovarian cancer group.

CONCLUSION

The CCR2 (+190 G/A) GG genotype may be a potential risk factor for the severe forms of ovarian cancer and the A allele may be a risk-reducing factor for severe ovarian cancer.

Possible contribution of chemokine receptor CCR2 and CCR5 polymorphisms in the pathogenesis of chronic spontaneous autoreactive urticaria

BACKGROUND

Autoimmune mechanisms play a role in the pathophysiology of chronic urticaria. As the genetic background of autoimmunity is well proven, the role of genetics in chronic urticaria is hypothesised.

METHODS

153 unrelated chronic spontaneous urticaria patients with a positive result of autologous serum skin test were included into the study, as were 115 healthy volunteers as control group. In all subjects we analysed CCR2 G190A and CCR5 d32 polymorphisms.

RESULTS

We noticed higher prevalence of CCR2 A allele as well as lower frequency of CCR5 d32 in chronic urticaria group in comparison to control group, with borderline statistical significance. Additionally, we assumed haplotype Gd statistically significant negative chronic urticaria association with tendency to higher frequency of Aw haplotype in this group.

CONCLUSIONS

The results of our study imply the role of autoimmune components in chronic urticaria pathogenesis and present chronic urticaria as possibly genetically related disorder.

Association of chemokine receptor gene variants with HIV-1 genotype predicted tropism

OBJECTIVES

As a switch from chemokine (C-C motif) receptor 5 [CCR5 (R5)] to chemokine (C-X-C motif) receptor 4 [CXCR4 (X4)] HIV-1 tropism is associated with symptomatic and AIDS stages of infection, while chemokine receptor gene variants modify the tempo of HIV disease progression, we aimed to analyse the association between pretreatment HIV-1 tropism and chemokine polymorphisms known to restrict disease progression.

METHODS

V3 genotype tropism prediction was performed in a group of 221 treatment-naïve patients, with subsequent CCR5 Δ32 (rs333), CCR2 V64I (rs1799864), CCR5 promoter (-627 C/T; rs1799988) and CX3CR1 V249I (rs3732378) genotyping performed in 206 patients. Alleles with a protective effect were assigned positive values while risk alleles were assigned negative values to calculate genetic scores. χ(2) tests, Mann-Whitney U-tests and logistic and linear regression models were used for statistical analyses.

RESULTS

R5 tropism was found in 85.5% of patients (n = 189) using a false positive rate (FPR) of 5.75% and in 72.8% of patients (n = 161) using an FPR of 10%. A higher frequency of the 5.75% FPR predicted R5 tropism was associated with the CX3CR1 A allele (P = 0.027). Lower additive genetic scores were associated with an increased frequency of 5.75% FPR predicted R5 tropism (P = 0.0059), with the trend confirmed by logistic regression [odds ratio (OR) 0.5819; 95% confidence interval (CI) 0.3457-0.9795; P = 0.0416]. Viral load tended to increase with decreasing genetic score in the logistic regression analysis (slope = -0.127 ± 0.076; P = 0.095; r(2)  = 0.161).

CONCLUSIONS

The CX3CR1 A allele and lower genetic scores may restrict the switch of HIV-1 tropism from R5 to X4. This effect may be associated with the amount of co-receptor on the cell surface. Chemokine receptor gene polymorphisms influence both disease progression and tropism variability.

Pro-inflammatory genetic markers of atherosclerosis

Atherosclerosis (AS) is a chronic, progressive, multifactorial disease mostly affecting large and medium-sized elastic and muscular arteries. It has formerly been considered a bland lipid storage disease. Currently, multiple independent pathways of evidence suggest this pathological condition is a peculiar form of inflammation, triggered by cholesterol-rich lipoproteins and influenced both by environmental and genetic factors. The Human Genome Project opened up the opportunity to dissect complex human traits and to understand basic pathways of multifactorial diseases such as AS. Population-based association studies have emerged as powerful tools for examining genes with a role in common multifactorial diseases that have a strong environmental component. These association studies often estimate the risk of developing a certain disease in carriers and non-carriers of a particular genetic polymorphism. Dissecting out the influence of pro-inflammatory genes within the complex pathophysiology of AS and its complications will help to provide a more complete risk assessment and complement known classical cardiovascular risk factors. The detection of a risk profile will potentially allow both the early identification of individuals susceptible to disease and the possible discovery of potential targets for drug or lifestyle modification; i.e. it will open the door to personalized medicine.

Host Factors and HIV-1 Replication: Clinical Evidence and Potential Therapeutic Approaches

HIV and human defense mechanisms have co-evolved to counteract each other. In the process of infection, HIV takes advantage of cellular machinery and blocks the action of the host restriction factors (RF). A small subset of HIV+ individuals control HIV infection and progression to AIDS in the absence of treatment. These individuals known as long-term non-progressors (LNTPs) exhibit genetic and immunological characteristics that confer upon them an efficient resistance to infection and/or disease progression. The identification of some of these host factors led to the development of therapeutic approaches that attempted to mimic the natural control of HIV infection. Some of these approaches are currently being tested in clinical trials. While there are many genes which carry mutations and polymorphisms associated with non-progression, this review will be specifically focused on HIV host RF including both the main chemokine receptors and chemokines as well as intracellular RF including, APOBEC, TRIM, tetherin, and SAMHD1. The understanding of molecular profiles and mechanisms present in LTNPs should provide new insights to control HIV infection and contribute to the development of novel therapies against AIDS.

Functional genetic polymorphisms of monocyte chemoattractant protein 1 and C-C chemokine receptor type 2 in ischemic stroke

Recent findings indicated that monocyte chemoattractant protein 1 (MCP1) and its C-C chemokine receptor type 2 (CCR2) play a key role in ischemic stroke (IS) progression. This study was aimed at evaluating the potential association of the MCP1 gene (MCP1) rs1024611 (-2518 A>G) and CCR2 gene (CCR2) rs1799864 (V64I; 190 G>A) functional single nucleotide polymorphisms (SNPs) with IS in the Armenian population. For the purpose of this study, genomic DNA samples of 100 patients with the first-episode IS and 115 healthy subjects (controls) were genotyped for the selected SNPs using a polymerase chain reaction with sequence-specific primers. The results obtained demonstrated that while the CCR2 rs1799864 SNP genotypes were equally distributed among patients and controls, the frequency and carriage rate of the of the MCP1 rs1024611*G minor allele were higher in patients. While a potential association between IS and CCR2 rs1799864 SNP was evaluated for the first time, the latest finding was in agreement with the earlier data reported for some other populations. In summary, this study revealed no association of CCR2 rs1799864 SNP with IS, and a positive association between G minor allele of MCP1 rs1024611 SNP and IS in the Armenian population. Based on the present and earlier reported data, we concluded that the minor G allele of the MCP1 rs1024611 SNP might be considered a risk factor for IS.

Association of polymorphisms in the MCP-1 and CCR2 genes with the risk of cancer: a meta-analysis

Studies investigating the impact of polymorphisms on monocyte chemotactic protein-1 (MCP-1) and CC chemokine receptor 2 (CCR2) on the risk of cancer have reported inconsistent results. We performed a meta-analysis of 23 eligible studies to summarize the data describing the association between cancer risk and polymorphisms in MCP-1 A2518G and CCR2 V64I. Q-statistics and I(2) statistics were calculated to examine heterogeneity and summary odds ratios (ORs) and 95% confidence intervals (95% CI) were calculated using a random effects model. Potential sources of heterogeneity were investigated via subgroup and sensitivity analyses, and publication biases were estimated. Overall, MCP-1 and CCR2 polymorphisms showed no significant associations with cancer risk (MCP-1-2518A/G, GG + GA vs. AA: OR=0.94, 95% CI=0.76-1.17; CCR2 V64I, AA+AG vs. GG: OR=1.27, 95% CI=0.87-1.86). However, strong evidence of heterogeneity was found among the investigated studies, and subgroup analyses were therefore conducted according to study location, cancer type, source of controls, and presence of deviation from the Hardy-Weinberg equilibrium (HWE). When the data were stratified by study location, the increased risk of cancer among A allele carriers of CCR2 V64I was observed only in studies conducted in Asian countries (AA+AG vs. GG: OR=1.65; 95% CI=1.25-2.18). This meta-analysis suggests that genetic polymorphisms of CCR2 V64I may influence the susceptibility of cancer in Asian countries. Further well-designed studies with larger sample sizes should be conducted.

A naturally occurring single amino acid substitution in human TRIM5α linker region affects its anti-HIV type 1 activity and susceptibility to HIV type 1 infection

TRIM5α is a factor contributing to intracellular defense mechanisms against retrovirus infection. Rhesus and cynomolgus monkey TRIM5αs potently restrict HIV-1, whereas human TRIM5α shows weak effects against HIV-1. We investigated the association between a single nucleotide polymorphism in the TRIM5α linker 2 region (rs11038628), which substituted aspartic acid (D) for glycine (G) at position 249, with susceptibility to HIV-1 infection in Japanese and Indian subjects. rs11038628 is rare in Europeans but common in Asians and Africans. Functional analyses were performed by multiple-round replication and single-round assays, and indicated that the G249D substitution attenuated anti-HIV-1 activity of human TRIM5α. A slight attenuation of anti-HIV-2 activity was also observed in TRIM5α with 249D. The predicted secondary structure of the linker region suggested that the 249D substitution extended the α-helix in the neighboring coiled-coil domain, suggesting that human TRIM5α with 249D may lose the flexibility required for optimal recognition of retroviral capsid protein. We further analyzed the frequency of G249D in Japanese (93 HIV-1-infected subjects and 279 controls) and Indians (227 HIV-1-infected subjects and 280 controls). The frequency of 249D was significantly higher among HIV-1-infected Indian subjects than in ethnicity-matched control subjects [odds ratio (OR)=1.52, p=0.026]. A similar weak tendency was observed in Japanese subjects, but it was not statistically significant (OR=1.19, p=0.302). In conclusion, G249D, a common variant of human TRIM5α in Asians and Africans, is associated with increased susceptibility to HIV-1 infection.

Relationship between CCR2-V64I polymorphism and cancer risk: a meta-analysis

BACKGROUND AND OBJECTIVES

The role of CCR2-V64I polymorphism in various cancers has been reported in many studies. However, results from published studies on the association between CCR2-V64I polymorphism and cancer risk are conflicting. Therefore, we performed a meta-analysis to estimate the overall cancer risk associated with the polymorphism.

METHODS

Electronic searches of PubMed and EMBASE were conducted for all publications on the association between this variant and cancer. Odds ratios (OR) with 95% confidence intervals (95% CI) were used to access the strength of this association.

RESULTS

Sixteen studies with 2661 cancer patients and 5801 healthy controls were included. Overall, significant association was found between the CCR2-V64I polymorphism and cancer risk (OR=1.84, 95% CI=1.35-2.51, AA vs GA/GG, P=0.37). In the subgroup analysis stratified by cancer types, there was a significant association between this polymorphism and bladder cancer (OR=2.06, 95% CI=1.02-4.15, AA vs GA/GG, P=0.11), cervical cancer (OR=3.34, 95% CI=1.48-7.50, AA vs GG, P=0.56), and oral cancer (OR=2.04, 95% CI=1.46-2.84, GA vs GG, P=0.70). In the subgroup analysis stratified by ethnicities, an increased cancer risk was also found in Europeans (OR=2.31, 95% CI=1.45-3.68, AA vs GA/GG, P=0.16) and Asians (OR=1.88, 95% CI=1.12-3.16, AA vs GA/GG, P=0.92).

CONCLUSION

This meta-analysis suggested that CCR2-V64I polymorphism may contribute to an increased risk of cancer.

Relationships of single nucleotide polymorphisms of monocyte chemoattractant protein 1 and chemokine receptor 2 with susceptibility and clinicopathologic characteristics of neoplasia of uterine cervix in Taiwan women

Few studies reported the implication of single nucleotide polymorphisms (SNPs) of monocyte chemoattractant protein 1 (MCP-1) and its receptor chemokine receptor 2 (CCR-2) in clinical significance of cancer of uterine cervix. We hypothesized that SNPs of MCP-1 and CCR-2 may affect the expression of these genes and then proteins. Therefore, we investigated the influence of the gene polymorphisms of MCP-1 and CCR-2 on the susceptibility and clinicopathologic characteristics of cervical neoplasia in Taiwan women. We recruited 86 patients with invasive cancer and 61 with high-grade dysplasia and 253 control women and selected 1 MCP-1 SNP rs1024611 (-2518G/A) and 1 CCR-2 SNP rs1799864 (190G/A; V64I) to determine their genotypes distribution using polymerase chain reaction-restriction fragment length polymorphism. In comparison to normal individuals with homozygotes GG in MCP-2 SNP, women with GA or AA carried a 2.01 odds ratio of developing cervical cancer. Nevertheless, it was not demonstrated in CCR-2 SNP. Furthermore, women with mutant homozygote (AA) of MCP-1 SNP increased the risk of deep stromal invasion, large tumor diameter, and parametrium invasion of cervical cancer, when compared to those with wild homozygote GG or heterozygote GA. However, women with mutant homozygotes (AA) of CCR-2 SNP did not increase the risk of poor clinicopathologic characteristics. In conclusion, MCP-1 SNP may be correlated with the development, deep stromal invasion, large tumor diameter, and parametrium invasion of cervical cancer but not with cancer recurrence or survival of Taiwan women patients with cancer. However, the SNP of its receptor, CCR-2, is not implicated in cervical cancer.

Impact of CCL2 and Its Receptor CCR2 Gene Polymorphism in North Indian Population: A Comparative Study in Different Ethnic Groups Worldwide

Chemokine are small, inducible pro-inflammatory cytokines involved in many biological processes, such as migration of leukocytes, atherosclerosis, angiogenesis, tumor growth, and metastasis. Chemokine are also known to influence tumor cell's activity. Specifically, tumor cells express chemokine receptors in a non random manner suggesting a role of chemokine in metastatic destination of tumor cells. The present study was conducted to determine distribution of (Chemokine receptor 2) CCR2 V64I, Chemokine ligand 2 CCL2 I/D, and CCL2 2518 A>G gene polymorphisms in North Indian population and compare with different populations globally. Polymerase chain reaction (PCR)-based analysis was conducted in 200 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type (GG) of CCR2 V64I G>A were 63 % G; CCL2 I/D 42 % II; CCL2 2518 A>G 40.5 % A. The minor variant allele frequency in our population was as follows: 19.5 % for CCR2 V64I, 35.5 % for CCL2 I/D, 35.3 % for CCL2 2518 A>G. We further compared frequency distribution for these genes with various published studies in different ethnicity. Our results suggested that frequency in chemokine genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of human exposed to environmental carcinogens and cancer predisposition in different ethnic groups. Thus, they signify an impact of ethnicity and provide a basis for future epidemiological and clinical studies.

The effect of chemokine receptor gene polymorphisms (CCR2V64I, CCR5-59029G>A and CCR5Δ32) on renal allograft survival in Pakistani transplant patients

BACKGROUND

Gene polymorphisms of the chemokine receptors CCR2 and CCR5 (CCR2V64I, CCR5-59029G>A and CCR5Δ32) have been shown to be associated with renal allograft rejection. The aim of this study was to investigate the association of these polymorphisms with allograft rejection among Pakistani transplant patients.

METHOD

A total of 606 renal transplant patients and an equal number of their donors were included in this study. DNA samples were used to amplify polymorphic regions of CCR2V64I, CCR5-59029G>A and CCR5Δ32 by polymerase chain reaction using sequence specific primers. The amplified products of CCRV64I and CCR5-59029G>A were digested with restriction enzymes (BsaB1 and Bsp12861) respectively. The CCR5Δ32 genotypes were determined by sizing the PCR amplicons. The association of these polymorphisms with the biopsy proven rejection and other clinical parameters was evaluated using the statistical software SPSS v.17.

RESULTS

In this study, the G/G genotype of CCR2V64I was associated with a high frequency of allograft rejection (p=0.009; OR=2.14; 95% CI=1.2-3.7). Rejection episode(s) in the GA+AA genotypes were found to be significantly lower as compared to the GG genotype (p=0.009; OR=0.4; 95% CI=0.2-0.8). The Kaplan-Meier curve also indicated a reduced overall allograft survival for patients with the G/G genotype of CCR2V64I (59.2 ± 1.4 weeks, log p=0.008). There was a significant association with rejection by female donors possessing the CCR2 GG genotype (p=0.02; OR=2.6; CI=1.1-6.3) and male donors with the CCR5-59029 GG genotype (p=0.004; OR=1.7; CI=1.03-3.01).

CONCLUSION

This study shows an association of the CCR2V64I (G/G) genotype with renal allograft rejection. However, no such association was found for the CCR5 gene polymorphisms. Therapeutic interventions such as blocking the CCR2 receptor (especially G polymorphism) may yield better survival of renal allograft in this patient group. Further, chemokine receptors may be added to the spectrum of the immunogenetic factors that are known to be associated with renal allograft rejection.

Genetic polymorphisms of CCL2, CCL5, CCR2 and CCR5 genes in Sahariya tribe of North Central India: an association study with pulmonary tuberculosis

The association of genetic variants of chemokines, CCL2 [MCP-1 (monocyte chemoattractant protein-1)], CCL5 [RANTES (regulated on activation, normal T-cell expressed and secreted)] and their receptors CCR2 and CCR5, respectively, earlier reported to be associated with susceptibility to pulmonary tuberculosis (PTB) in certain ethnic populations, were explored in Sahariya tribe, a primitive tribe of North Central India having a high prevalence of TB. We genotyped 215 cases and 215 controls of Sahariya tribe for polymorphisms in CCL2 (-2518A/G, -362G/C) by PCR-RFLP method and in CCR2 (V64I), CCL5 (-403G/A, -28C/G) and CCR5 (-59029G/A) by ARMS-PCR method. The frequencies of 'AA' genotype and 'A' allele of -403G/A were found significantly higher in cases than in controls (OR, 2.616 [95%CI, 1.302-5.320] and OR, 1.348 [95%CI, 0.980-1.853], respectively). Conversely, the frequencies of 'AA' genotype and 'A' allele of V64I were significantly (p=0.05 and 0.04, respectively) higher in controls than in cases. Also, the "AA" genotype of V64I was found to provide significant (p=0.05) protection against high bacillary load (3+). Likewise, the comparison of frequencies of different combinations of these polymorphisms further strengthens the association of -403G/A with susceptibility and V64I with resistance to TB in Sahariya tribe. However, no significant association of other polymorphisms with either resistance or susceptibility to TB was found. Thus, our findings support the association of -403G/A and V64I polymorphisms with genetic susceptibility and resistance to TB, respectively , alone or in combination with other polymorphisms in Sahariya tribe.

The effect of combined polymorphisms in chemokines and chemokine receptors on the clinical course of HIV-1 infection in a Brazilian population

Polymorphisms in genes that encode chemokines or their receptors can modulate susceptibility to human immunodeficiency virus (HIV) infection and disease progression. The objective of this study was to assess the frequency of polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A and their role in the course of HIV infection in a Southern Brazilian population. Clinical data were obtained from 249 patients for an average period of 6.4 years and genotypes were determined by standard polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism. Survival analyses were conducted for three outcomes: CD4+ T-cell counts below 200 cells/µL, acquired immune deficiency syndrome (AIDS) or death. The frequency of the polymorphisms CCR5-Δ32, CCR2-64I, CCR5-59029A and SDF1-3'A were 0.024, 0.113, 0.487 and 0.207, respectively. CCR5-Δ32 was associated with a reduction in the risk for CD4+ T-cell depletion and with an increased risk for death after AIDS diagnosis. CCR2-64I was associated with a reduction in the risk for developing AIDS. SDF1-3'A was also associated with decreased risk for AIDS, but its effect was only evident when CCR2-64I was present as well. These results highlight the possibility of using these markers as indicators for the prognosis of disease progression and provide evidence for the importance of analysing the effects of gene polymorphisms in a combined fashion.

The association of monocyte chemotactic protein-1 and CC chemokine receptor 2 gene variants with chronic obstructive pulmonary disease

Chemokines are potent proinflammatory cytokines that are implicated in numerous inflammatory diseases. Monocyte chemoattractant protein-1 (MCP-1) and its receptor CC chemokine receptor-2 (CCR2) play a major role in the recruitment of inflammatory cells to the lungs of patients with chronic obstructive pulmonary disease (COPD). We investigated a possible association between polymorphisms in MCP-1 and CCR2 genes (MCP-1 -2518 A/G and CCR2 190G/A or V64I) and the development of COPD. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism in 386 COPD cases and 398 age-matched healthy controls. Frequency of MCP-1 2518GG genotype for cases and controls was 0.396 and 0.324, respectively; individuals who had the GG genotype had a 1.59-fold increased risk of COPD (p=0.036). Frequency of CCR2 190AA (64I/64I) genotype for cases and controls was 0.285 and 0.21, respectively; subjects carrying the 64I/64I genotype had a 2.04-fold increased risk of COPD compared with the wild-type genotype (p=0.001). When analyzing the allele combination of these two polymorphisms, the combinations MCP-1-A/CCR2-A and MCP-1-G/CCR2-A were detected in significantly higher numbers in COPD cases than in healthy controls (odds ratio [OR]=1.50, 95% confidence interval [CI]: 1.04-2.17, p=0.032; and OR=1.89, 95% CI: 1.38-2.60, p=7.38×10(-5)). These data suggest that MCP-1 -2518 A/G and CCR2 190G/A polymorphisms are new risk factors for COPD.

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.

Immunogenetic factors associated with severe respiratory illness caused by zoonotic H1N1 and H5N1 influenza viruses

Following the 2009 H1N1 pandemic and ongoing sporadic avian-to-human transmission of H5N1 viruses, an emphasis has been placed on better understanding the determinants and pathogenesis of severe influenza infections. Much of the current literature has focused on viral genetics and its impact on host immunity as well as novel risk factors for severe infection (particularly within the H1N1 pandemic). An understanding of the host genetic determinants of susceptibility and severe respiratory illness, however, is currently lacking. By better defining the role of genetic variability in influenza infection and identifying key polymorphisms that impair the host immune response or correlate with protection, we will be able to better identify at-risk populations and new targets for therapeutic interventions and vaccines. This paper will summarize known immunogenetic factors associated with susceptibility or severity of both pH1N1 and H5N1 infections and will also identify genetic pathways and polymorphisms of high relevance for future study.

Genetics in arterial calcification: pieces of a puzzle and cogs in a wheel

Artery calcification reflects an admixture of factors such as ectopic osteochondral differentiation with primary host pathological conditions. We review how genetic factors, as identified by human genome-wide association studies, and incomplete correlations with various mouse studies, including knockout and strain analyses, fit into "pieces of the puzzle" in intimal calcification in human atherosclerosis, and artery tunica media calcification in aging, diabetes mellitus, and chronic kidney disease. We also describe in sharp contrast how ENPP1, CD73, and ABCC6 serve as "cogs in a wheel" of arterial calcification. Specifically, each is a minor component in the function of a much larger network of factors that exert balanced effects to promote and suppress arterial calcification. For the network to normally suppress spontaneous arterial calcification, the "cogs" ENPP1, CD73, and ABCC6 must be present and in working order. Monogenic ENPP1, CD73, and ABCC6 deficiencies each drive a molecular pathophysiology of closely related but phenotypically different diseases (generalized arterial calcification of infancy (GACI), pseudoxanthoma elasticum (PXE) and arterial calcification caused by CD73 deficiency (ACDC)), in which premature onset arterial calcification is a prominent but not the sole feature.

Polymorphisms in chemokine and receptor genes and gastric cancer risk and survival in a high risk Polish population

OBJECTIVE

To examine if genetic variations in chemokine receptor and ligand genes are associated with gastric cancer risk and survival.

METHODS

The study included 298 cases and 417 controls from a population-based study of gastric cancer conducted in Warsaw, Poland in 1994-1996. We investigated seven single nucleotide polymorphisms in a chemokine ligand (CXCL12) and chemokine receptor (CCR2, CCR5, CX3CR1) genes and one frameshift deletion (CCR5) in blood leukocyte DNA in relation to gastric cancer risk and survival. Genotyping was conducted at the NCI Core Genotyping Facility. Odds ratios and 95% confidence intervals were computed using univariate and multivariate logistic regression models. Survival analysis was performed using Cox proportional hazards models.

RESULTS

Gastric cancer risk was not associated with single chemokine polymorphisms. A CCR5 haplotype that contained the common alleles of IVS1+151 G>T (rs2734648), IVS2+80 C>T (rs1800024) and minor allele of IVS1+246 A>G (rs1799987) was associated with a borderline significantly increased risk (OR = 1.5, 95% CI: 1.0?2.2). For gastric cancer cases, there was a greater risk of death for carriers of the minor alleles of CCR2 Ex2+241 G>A (rs1799864) (HR = 1.5, 95% CI: 1.1-2.1) and CCR5 IVS2+80 C>T (rs1800024) (HR = 1.5, 95% CI: 1.1-2.1). Carriers of the CCR5 minor allele of IVS1+151 G>T (rs2734648) had a decreased risk of death compared to homozygote carriers of the common allele (HR = 0.8, 95% CI: 0.6-1.0).

CONCLUSIONS

Our findings do not support an association between gastric cancer risk and single chemokine genetic variation. The observed associations between cancer risk and a CCR5 haplotype and between survival and polymorphisms in CCR2 and CCR5 need replication in future studies.

Genetic polymorphism of CCR2-64I increased the susceptibility of hepatocellular carcinoma

BACKGROUND AND OBJECTIVES

The purpose of this study was to investigate genetic impact of monocyte chemoattractant protein-1 (MCP-1) and its receptor chemokine receptor-2 (CCR2) gene polymorphisms on the susceptibility and clinicopathological characteristics of hepatocellular carcinoma (HCC).

METHODS

A total of 446 subjects, including 344 healthy controls and 102 patients with HCC, were recruited in this study and subjected to PCR-RFLP to estimate the impact of these two polymorphic variants on HCC.

RESULTS

No relationship between MCP-1 -2518G/A gene polymorphism and HCC risk was found among our recruited HCC patients and healthy controls. However, there was a significantly increased risk (AOR = 1.91; 95% CI = 1.11-3.29) of having HCC among subjects with GA heterozygotes of CCR2 V64I after adjusting for other confoundings. There was no synergistic effect between gene polymorphism and environmental risk factors, including tobacco and alcohol consumptions, as well as clinicopathological parameters of HCC for MCP-1 -2518G/A and CCR2 V64I genes, respectively.

CONCLUSIONS

CCR2-64I gene polymorphism is an important factor for the susceptibility of HCC but it might not influence the clinical pathological progression of HCC, and the contribution of CCR2-64I gene polymorphism on the susceptibility of HCC could be not through the affection of liver injury-related clinical pathological characteristics.

Gene expression variability within and between human populations and implications toward disease susceptibility

Variations in gene expression level might lead to phenotypic diversity across individuals or populations. Although many human genes are found to have differential mRNA levels between populations, the extent of gene expression that could vary within and between populations largely remains elusive. To investigate the dynamic range of gene expression, we analyzed the expression variability of ∼18, 000 human genes across individuals within HapMap populations. Although ∼20% of human genes show differentiated mRNA levels between populations, our results show that expression variability of most human genes in one population is not significantly deviant from another population, except for a small fraction that do show substantially higher expression variability in a particular population. By associating expression variability with sequence polymorphism, intriguingly, we found SNPs in the untranslated regions (5′ and 3′UTRs) of these variable genes show consistently elevated population heterozygosity. We performed differential expression analysis on a genome-wide scale, and found substantially reduced expression variability for a large number of genes, prohibiting them from being differentially expressed between populations. Functional analysis revealed that genes with the greatest within-population expression variability are significantly enriched for chemokine signaling in HIV-1 infection, and for HIV-interacting proteins that control viral entry, replication, and propagation. This observation combined with the finding that known human HIV host factors show substantially elevated expression variability, collectively suggest that gene expression variability might explain differential HIV susceptibility across individuals.

Many human genes have population-specific expression levels, which are linked to population-specific polymorphisms and copy-number variations. However, it is unclear whether human genes show similar dynamic range of expression between populations. In this work we analyzed HapMap gene expression compendium, and quantified the between-population and within-population expression variability for ∼18,000 human transcripts. We first concluded that the majority of the human genes have similar levels of within-population variability. However, a small fraction (∼4%) does show much higher expression variability in one population, and the deviation is consistently associated with increased SNP heterozygosity in their UTR regulatory regions. We further showed that genes with the greatest within-population expression variability are significantly enriched for chemokine signaling associated with HIV-1 infection. Combined with the finding that human HIV-1 host factors tend to have increased expression variability within populations, our analysis may explain, at least in part, different susceptibility to HIV infection within the human population. This work provides a fresh angle for analyzing gene expression variations in populations.

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.

Inflammatory genetic markers of prostate cancer risk

Prostate cancer is the most common cancer in Western society males, with incidence rates predicted to rise with global aging. Etiology of prostate cancer is however poorly understood, while current diagnostic tools can be invasive (digital rectal exam or biopsy) and/or lack specificity for the disease (prostate-specific antigen (PSA) testing). Substantial histological, epidemiological and molecular genetic evidence indicates that inflammation is important in prostate cancer pathogenesis. In this review, we summarize the current status of inflammatory genetic markers influencing susceptibility to prostate cancer. The focus will be on inflammatory cytokines regulating T-helper cell and chemokine homeostasis, together with the Toll-like receptors as key players in the host innate immune system. Although association studies indicating a genetic basis for prostate cancer are presently limited mainly due to lack of replication, larger and more ethnically and clinically defined study populations may help elucidate the true contribution of inflammatory gene variants to prostate cancer risk.

Host genetics influences on HIV type-1 disease

HIV host genetic studies seek to describe as comprehensively as possible the effect of human genetic variation on the individual response to HIV type-1 (HIV-1) infection. Many associations between specific gene variants and HIV-1 disease outcomes have been reported over the past 15 years. Although most of them have yet to be confirmed or have been proven false-positives, the identification of several definitive genotype-phenotype associations has shed new light on HIV-1 pathogenesis. This review discusses these results in the context of the new genome-wide approaches that now make it possible to globally assess the influence of the host genome on HIV-1-related outcomes.

Structure and function of the human Gly1619Arg polymorphism of M6P/IGF2R domain 11 implicated in IGF2 dependent growth

The mannose 6-phosphate/IGF 2 receptor (IGF2R) is comprised of 15 extra-cellular domains that bind IGF2 and mannose 6-phosphate ligands. IGF2R transports ligands from the Golgi to the pre-lysosomal compartment and thereafter to and from the cell surface. IGF2R regulates growth, placental development, tumour suppression and signalling. The ligand IGF2 is implicated in the growth phenotype, where IGF2R normally limits bioavailability, such that loss and gain of IGF2R results in increased and reduced growth respectively. The IGF2R exon 34 (5002A>G) polymorphism (rs629849) of the IGF2 specific binding domain has been correlated with impaired childhood growth (A/A homozygotes). We evaluated the function of the Gly1619Arg non-synonymous amino acid modification of domain 11. NMR and X-ray crystallography structures located 1619 remote from the ligand binding region of domain 11. Arg1619 was located close to the fibronectin type II (FnII) domain of domain 13, previously implicated as a modifier of IGF2 ligand binding through indirect interaction with the AB loop of the binding cleft. However, comparison of binding kinetics of IGF2R, Gly1619 and Arg1619 to either IGF2 or mannose 6-phosphate revealed no differences in 'on' and 'off' rates. Quantitative PCR, (35)S pulse chase and flow cytometry failed to demonstrate altered gene expression, protein half-life and cell membrane distribution, suggesting the polymorphism had no direct effect on receptor function. Intronic polymorphisms were identified which may be in linkage disequilibrium with rs629849 in certain populations. Other potential IGF2R polymorphisms may account for the correlation with childhood growth, warranting further functional evaluation.

Silencing of tripartite motif protein (TRIM) 5alpha mediated anti-HIV-1 activity by truncated mutant of TRIM5alpha

Tripartite motif protein (TRIM) 5alpha is a restriction factor of human immunodeficiency virus type 1 in Old World monkey cell. It was found that both naturally occurring and artificial TRIM5alpha variants lacking the SPRY domain could silence TRIM5alpha activity. Specifically, the artificial TRIM5alpha mutant could suppress TRIM5alpha activity of various primate species with even higher efficiency than could small interfering RNAs. The findings indicate that TRIM5alpha variants lacking the SPRY domain are useful for silencing TRIM5alpha activity.