Regulatory polymorphisms in extracellular matrix protease genes and susceptibility to rheumatoid arthritis: a case-control study

Bacillus coagulans BACO-17 ameliorates in vitro and in vivo progression of Rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune disease that causes persistent inflammation involving the joints, cartilage, and synovium. In individuals with RA, alterations in the composition of intestinal bacteria suggest the vital role of gut microbiota in immune dysfunction. Multiple therapies commonly used to treat RA can also alter the diversity of gut microbiota, further suggesting the modulation of gut microbiota as a prevention or treatment for RA. Therefore, a better understanding of the changes in the gut microbiota that accompany RA should facilitate the development of novel therapeutic approaches. In this study, B. coagulans BACO-17 not only significantly reduced paw swelling, arthritis scores, and hind paw and forepaw thicknesses but also protected articular cartilage and the synovium against RA degeneration, with a corresponding downregulation of TNF-α expression. The inhibition or even reversing of RA progression highlights B. coagulans BACO-17 as a novel therapeutic for RA worth investigating.

High Prevalence of Prediabetes and Associated Risk Factors in Urban Areas of Pontianak, Indonesia: A Cross-Sectional Study

Uncontrolled prediabetes can develop into Type 2 Diabetes mellitus (T2DM). The incidence of T2DM among adults in Pontianak, Indonesia was reported remarkably high. Therefore, this study aimed to investigate the risk factors for prediabetes in adults living in urban areas of Pontianak, Indonesia. A cross-sectional study was conducted in 5 subdistricts of Pontianak. A total of 506 adults underwent screening to obtain subjects with fasting blood glucose (FBS) of ≤124 mg/dL and aged >30 years. Blood pressure and body mass index (BMI) were measured. Interview using a structured questionnaire were performed to obtain data on predictor variables (age, sex, education, income, health insurance, tobacco use, history of hypertension, gout, high cholesterol level, frequency of exercise per week, and diabetic education). The prevalence of prediabetes among subjects was significantly high (76.4%). Subjects were predominantly above 40 years, female, had low income, low education level, and had health insurance. About a third of the subjects had a history of hypertension, gout, and high cholesterol level, respectively. The exercise frequency was mostly less than 3 times/week, and the BMI was mainly classified as overweight and obese. The result of spearman's rho correlation showed that age (r = 0.146; p=0.022) and BMI (r = 0.130; p=0.041) significantly correlated with prediabetes incidence. Moreover, the chi-square analysis demonstrated that health insurance ownership (OR = 4.473; 95% CI 1.824-10.972; p ≤ 0.001), history of hypertension (OR = 3.096; 95% CI 1.542-6.218; p=0.001), and history of gout (OR = 2.419; 95% CI 1.148-5.099; p=0.018), were associated with prediabetes incidence. For all these significant risk predictors except BMI, the significant associations were found only among female subjects after specific sex analysis. Moreover, multivariate logistic regression showed that health insurance ownerships (OR = 5.956; 95% CI 2.256-15.661; p ≤ 0.001) and history of hypertension (OR = 3.257; 95% CI 1.451-7.311; p=0.004), and systolic blood pressure (OR = 2.141; 95% CI 1.092-4.196; p=0.027) were the risk factors for prediabetes. It is concluded that the prevalence of prediabetes is probably high especially among urban people in Pontianak, Indonesia. Health insurance ownership and hypertension may have an important role in prediabetes management. The risk factors might be different between male and female.

Genetic Correlation Analysis and Transcriptome-wide Association Study Suggest the Overlapped Genetic Mechanism between Gout and Attention-deficit Hyperactivity Disorder

OBJECTIVES

Gout is a common inflammatory arthritis, which is caused by hyperuricemia. Limited efforts have been paid to systematically explore the relationships between gout and common psychiatric disorders.

METHODS

Genome-wide association study summary data of gout were obtained from the GeneATLAS, which contained 452,264 participants including 3,528 gout cases. Linkage disequilibrium score regression (LDSC) was first conducted to evaluate the genetic relationships between gout and 5 common psychiatric disorders. Transcriptome-wide association studies (TWAS) was then conducted to explore the potential biological mechanism underlying the observed genetic correlation between gout and attention-deficit hyperactivity disorder (ADHD). The Database for Annotation, Visualization and Integrated Discovery online functional annotation system was applied for pathway enrichment analysis and gene ontology enrichment analysis.

RESULTS

LDSC analysis observed significant genetic correlation between gout and ADHD (genetic correlation coefficients = 0.29, standard error = 0.09 and P value = 0.0015). Further TWAS of gout identified 105 genes with P value < 0.05 in muscle skeleton and 228 genes with P value < 0.05 in blood. TWAS of ADHD also detected 300 genes with P value < 0.05 in blood. Further comparing the TWAS results identified 9 common candidate genes shared by gout and ADHD, such as CD300C (P_gout = 0.0040; P_ADHD = 0.0226), KDM6B (P_gout = 0.0074; P_ADHD = 0.0460), and BST1 (P_gout = 0.0349; P_ADHD = 0.03560).

CONCLUSION

We observed genetic correlation between gout and ADHD and identified multiple candidate genes for gout and ADHD.

Role of MMP-2 and its inhibitor TIMP-2 as biomarkers for susceptibility to systemic lupus erythematosus

Aim: To investigate the possible association between MMP-2 (-1575 G/A, -1306 C/T) and its inhibitor TIMP-2 (-418 G/C) functional polymorphisms with development of severity in systemic lupus erythematosus (SLE) patients. Materials & methods: 150 SLE patients and matched healthy controls were recruited. Polymorphisms were detected by PCR-RFLP and serum levels by ELISA. Results: Mean MMP-2 and TIMP-2 serum level and mRNA expression were significantly increased in SLE cases as compared with controls (p < 0.0001). The concomitant presence of both MMP-2 1575A and its inhibitor TIMP-2 418C alleles synergistically increased the risk of SLE by 3.25-fold (CI: 1.44-7.34, p = 0.003). Conclusion: MMP-2, TIMP-2 and MMP-2/TIMP-2 ratios may act as biomarkers for susceptibility to SLE.

Epistasis of polymorphisms related to the articular cartilage extracellular matrix in knee osteoarthritis: Analysis-based multifactor dimensionality reduction

Osteoarthritis (OA) is a complex disease with a multifactorial etiology. The genetic component is one of the main associated factors, resulting from interactions between genes and environmental factors. The aim of this study was to identify gene-gene interactions (epistasis) of the articular cartilage extracellular matrix (ECM) in knee OA. Ninety-two knee OA patients and 147 healthy individuals were included. Participants were genotyped in order to evaluate nine variants of eight genes associated with ECM metabolism using the OpenArray technology. Epistasis was analyzed using the multifactor dimensionality reduction (MDR) method. The MDR analysis showed significant gene-gene interactions between MMP3 (rs679620) and COL3A1 (rs1800255), and between COL3A1 (rs1800255) and VEGFA (rs699947) polymorphisms, with information gain values of 3.21% and 2.34%, respectively. Furthermore, in our study we found interactions in high-risk genotypes of the HIF1AN, MMP3 and COL3A1 genes; the most representative were [AA+CC+GA], [AA+CT+GA] and [AA+CT+GG], respectively; and low-risk genotypes [AA+CC+GG], [GG+TT+GA] and [AA+TT+GA], respectively. Knowing the interactions of these polymorphisms involved in articular cartilage ECM metabolism could provide a new tool to identify individuals at high risk of developing knee OA.

Genetic polymorphism in the asporin gene is not a key risk factor for osteoarthritis: Evidence based on an updated cumulative meta-analysis

To provide an evidence-based medical basis for the treatment of osteoarthritis, a meta-analysis was performed to assess the association between asporin (ASPN) gene polymorphism and susceptibility to osteoarthritis (OA). The current study searched the literature from January 1st, 1915 through February 1st, 2017 using the Cochrane Library, PubMed, the Excerpta Medica database (EMBASE) and three main Chinese databases (VIP, CNKI and Wan Fang). Cohort and case-control studies that explored the association between different types of ASPN alleles and OA susceptibility were evaluated. The K/L grading system, clinical and radiological diagnoses were used for OA diagnosis. A random-effects model was used in a pooled analysis to adjust for heterogeneity of the included studies, and the differences between treatment groups were reported as odds ratio (OR), 95% confidence intervals (CIs) and P-values. Begg's funnel plots and Egger's tests were used to assess publication bias in the present meta-analysis. Following document retrieval and screening, a total of 10 studies were deemed eligible, including 4,842 patients and 3,661 healthy subjects. Results of the multivariate meta-regression analysis revealed that the study sample size was a source of heterogeneity between studies. The D17 allele was a risk factor for the development of OA (OR=1.33, 95% CI: 1.02–1.73, P<0.05). The other alleles were not considered as risk factors for development of OA (P>0.05). The results of the meta-analysis verified that ASPN polymorphisms were not significantly relevant to an increased OA risk. However, the mechanisms contributing to the association between ASPN polymorphisms and OA risk still require further study.

Association of tumor necrosis factor-α (G-308A) genetic variant with matrix metalloproteinase-9 activity and joint destruction in early rheumatoid arthritis

Matrix metalloproteinases (MMPs) are the key enzymes responsible for the joint destruction. Their activity is regulated by the level of proinflammatory cytokines. The aim of this study was to examine the impact of TNF-α G-308A polymorphism on MMP-9 levels in blood plasma (BP) and synovial fluid (SF) of patients with rheumatoid arthritis (RA) and their role in progression of joint destruction. One hundred thirty-four subjects were enrolled in this study. TNF-α G-308A polymorphism was determined using PCR-RFLP method. ELISA assay was used for the detection of MMP-9 activity in BP and SF. Joint damage was estimated by hands and feet radiography. Larsen score and annual changes in LS were used for quantitative evaluation of joint destruction and radiographic progression of disease. MMP-9 activity in BP and SF was significantly higher in RA compared to controls, as well as in SF of patients with erosive compared to nonerosive RA. Faster radiographic progression and increased MMP-9 activity in BP and SF were detected in the group A (GA or AA genotype carriers) compared to the group G (GG genotype carriers). However, statistical significance was revealed only for MMP-9 activity in SF (p < 0.05). MMP-9 activity in BP and SF is significantly higher in RA patients compared to patients with osteoarthritis. The presence of TNF-α-308A allele is associated with increased MMP-9 activity in SF of patients with early RA and may be a predictor of rapid radiographic progression of disease.

Regulation of Chemokine Activity - A Focus on the Role of Dipeptidyl Peptidase IV/CD26

Chemokines are small, chemotactic proteins that play a crucial role in leukocyte migration and are, therefore, essential for proper functioning of the immune system. Chemokines exert their chemotactic effect by activation of chemokine receptors, which are G protein-coupled receptors (GPCRs), and interaction with glycosaminoglycans (GAGs). Furthermore, the exact chemokine function is modulated at the level of posttranslational modifications. Among the different types of posttranslational modifications that were found to occur in vitro and in vivo, i.e., proteolysis, citrullination, glycosylation, and nitration, NH₂-terminal proteolysis of chemokines has been described most intensively. Since the NH₂-terminal chemokine domain mediates receptor interaction, NH₂-terminal modification by limited proteolysis or amino acid side chain modification can drastically affect their biological activity. An enzyme that has been shown to provoke NH₂-terminal proteolysis of various chemokines is dipeptidyl peptidase IV or CD26. This multifunctional protein is a serine protease that preferably cleaves dipeptides from the NH₂-terminal region of peptides and proteins with a proline or alanine residue in the penultimate position. Various chemokines possess such a proline or alanine residue, and CD26-truncated forms of these chemokines have been identified in cell culture supernatant as well as in body fluids. The effects of CD26-mediated proteolysis in the context of chemokines turned out to be highly complex. Depending on the chemokine ligand, loss of these two NH₂-terminal amino acids can result in either an increased or a decreased biological activity, enhanced receptor specificity, inactivation of the chemokine ligand, or generation of receptor antagonists. Since chemokines direct leukocyte migration in homeostatic as well as pathophysiologic conditions, CD26-mediated proteolytic processing of these chemotactic proteins may have significant consequences for appropriate functioning of the immune system. After introducing the chemokine family together with the GPCRs and GAGs, as main interaction partners of chemokines, and discussing the different forms of posttranslational modifications, this review will focus on the intriguing relationship of chemokines with the serine protease CD26.

Association of genetic and psychological factors with persistent pain after cosmetic thoracic surgery

The genetic control of pain has been repeatedly demonstrated in human association studies. In the present study, we assessed the relative contribution of 16 single nucleotide polymorphisms in pain-related genes, such as cathechol-O-methyl transferase gene (COMT), fatty acid amino hydrolase gene (FAAH), transient receptor potential cation channel, subfamily V, member 1 gene (TRPV1), and δ-opioid receptor gene (OPRD1), for postsurgical pain chronification. Ninety preoperatively pain-free male patients were assigned to good or poor outcome groups according to their intensity or disability score assessed at 1 week, 3 months, 6 months, and 1 year after funnel chest correction. The genetic effects were compared with those of two psychological predictors, the attentional bias toward positive words (dot-probe task) and the self-reported pain vigilance (Pain Vigilance and Awareness Questionnaire [PVAQ]), which were already shown to be the best predictors for pain intensity and disability at 6 months after surgery in the same sample, respectively. Cox regression analyses revealed no significant effects of any of the genetic predictors up to the end point of survival time at 1 year after surgery. Adding the genetics to the prediction by the attentional bias to positive words for pain intensity and the PVAQ for pain disability, again no significant additional explanation could be gained by the genetic predictors. In contrast, the preoperative PVAQ score was also, in the present enlarged sample, a meaningful predictor for lasting pain disability after surgery. Effect size measures suggested some genetic variables, for example, the polymorphism rs1800587G>A in the interleukin 1 alpha gene (IL1A) and the COMT haplotype rs4646312T>C/rs165722T>C/rs6269A>G/rs4633T>C/rs4818C>G/rs4680A>G, as possible relevant modulators of long-term postsurgical pain outcome. A comparison between pathophysiologically different predictor groups appears to be helpful in identifying clinically relevant predictors of chronic pain.

Genetic variations in MMP9 and MMP13 contribute to tooth agenesis in a Brazilian population

We investigated the association between polymorphisms in the MMP2 (rs243865), MMP9 (rs17576), and MMP13 (rs2252070) genes with tooth agenesis in humans. Two hundred eighty-five unrelated individuals (202 controls without tooth agenesis and 83 cases with tooth agenesis) were evaluated in a cross-sectional single-center study. The study participants were recruited through the Pediatric Dental Clinics of the Federal University of Rio de Janeiro, Brazil. Genotyping of the selected polymorphisms for MMPs was carried out by real-time PCR using the Taqman assay method from genomic DNA isolated from buccal epithelial cells of all the studied individuals. There was no significant association of MMP2 genotype or allele distribution with tooth agenesis or its absence. For MMP9, a significant difference in allele frequency was evident between the two groups (P = 0.05). With regard to the affected side, there was a significant difference between unilateral tooth agenesis and the control group in the distribution of MMP9 (P = 0.05). Also, there was a significant difference in MMP9 distribution between tooth agenesis in the maxilla and control individuals (P = 0.03). The genotype distribution of MMP13 differed significantly between the group with unilateral tooth agenesis and the controls (P = 0.01). Our findings provide evidence that MMP9 and MMP13 may be involved in tooth agenesis.

The Crosstalk of Pathways Involved in Immune Response Maybe the Shared Molecular Basis of Rheumatoid Arthritis and Type 2 Diabetes

Rheumatoid arthritis (RA) and Type 2 diabetes (T2D) are both systemic diseases linked with altered immune response, moderate mortality when present together. The treatment for both RA and T2D are not satisfied, partly because of the linkage between them has not yet been appreciated. A comprehensive study for the potential associations between the two disorders is needed. In this study, we used RNA sequencing to explore the differently expressed genes (DEGs) in peripheral blood mononuclear cells (PBMC) of 10 RA and 10 T2D patients comparing with 10 healthy volunteers (control). We used bioinformatics analysis and the Ingenuity Pathways Analysis (IPA) to predict the commonalities on signaling pathways and molecular networks between those two diseases. 212 DEGs in RA and 114 DEGs in T2D patients were identified compared with healthy controls, respectively. 32 DEGs were shared between the two comparisons. The top 10 shared pathways interacted in cross-talking networks, regulated by 5 shared predicted upstream regulators, leading to the activated immune response were explored, which was considered as partly of the association mechanism of this two disorders. These discoveries would be considered as new understanding on the associations between RA and T2D, and provide novel treatment or prevention strategy.

[Matrix metalloproteinase 2, 3, and 9 gene polymorphisms in women with rheumatoid arthritis]

AIM

To study the promoter regions of the matrix metalloproteinase (MMP)2, MMP3, and MMP9 genes to assess their associations with the risk of rheumatoid arthritis (RA) and with the types of its clinical course in women.

SUBJECTS AND METHODS

162 female patients with RA and 329 women without this condition were examined. Polymorphisms in the gene promoter region for MMP2 (-1306 С→Т), MMP3 (-1171 5A→6А), and MMP9 (-1562 С→Т) were studied. Genotyping was carried out using the restriction fragment length polymorphism method.

RESULTS

In the RA group, the -1306TT genotype of MMP2 was significantly more frequently encountered and the 6A6A genotype was less frequently seen. In the seropositive RA group, the frequency of the -1306ТТ genotype of MMP2 was significantly higher than that in the healthy individuals. The significant differences shown for the entire group of patients with RA were preserved when they were divided into groups according to the presence or absence of rheumatoid nodules. Furthermore, the frequency of the homozygous -1306 genotypes of MMP2 was higher in both groups than in the healthy individuals.

CONCLUSION

The presence of the allelic variants of the MMP genes may be one of the genetic factors that predispose to RA in women.

The shared crosstalk of multiple pathways involved in the inflammation between rheumatoid arthritis and coronary artery disease based on a digital gene expression profile

Rheumatoid arthritis (RA) and coronary artery disease (CAD) are both complex inflammatory diseases, and an increased prevalence of CAD and a high rate of mortality have been observed in RA patients. But the molecular mechanism of inflammation that is shared between the two disorders is unclear. High-throughput techniques, such as transcriptome analysis, are becoming important tools for genetic biomarker discovery in highly complex biological samples, which is critical for the diagnosis, prognosis, and treatment of disease. In the present study, we reported one type of transcriptome analysis method: digital gene expression profiling of peripheral blood mononuclear cells of 10 RA patients, 10 CAD patients and 10 healthy people. In all, 213 and 152 differently expressed genes (DEGs) were identified in RA patients compared with normal controls (RA vs. normal) and CAD patients compared with normal controls (CAD vs. normal), respectively, with 73 shared DEGs between them. Using this technique in combination with Ingenuity Pathways Analysis software, the effects on inflammation of four shared canonical pathways, three shared activated predicted upstream regulators and three shared molecular interaction networks were identified and explored. These shared molecular mechanisms may provide the genetic basis and potential targets for optimizing the application of current drugs to more effectively treat these diseases simultaneously and for preventing one when the other is diagnosed.

Lack of association of matrix metalloproteinase-3 gene polymorphism with susceptibility to rheumatoid arthritis: a meta-analysis

Background

Epidemiological studies have investigated the association between matrix metalloproteinase-3(MMP-3) gene-1171 5A/6A polymorphism and rheumatoid arthritis (RA), but the results were inconsistent. To evaluate the specific relationship, we performed a meta-analysis to clarify the controversies.

Methods

The relevant literatures dated to December 07th 2013 were retrieved from PubMed, EMBASE and the China National knowledge Infrastructure (CNKI) databases. The number of the alleles and genotypes for MMP-3 were obtained. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the association between MMP-3 5A/6A promoter polymorphism and RA. All of the statistical analyses were conducted by STATA11.0 software.

Results

A total of 6 case-control studies covering 1451 cases and 1239 controls were included in the final meta-analysis. There was no significant association between MMP-3 5A/6A promoter polymorphism and RA in all genetic models (for 6A versus 5A: OR = 1.19, 95% CI = 0.91-1.56, P = 0.203; 5A/6A versus 5A/5A: OR = 1.31, 95% CI = 0.89-1.92, P = 0.174; 6A/6A versus 5A/5A: OR = 1.78, 95% CI = 0.68-4.61, P = 0.238; the recessive model: OR = 1.48, 95% CI = 0.88-2.47, P = 0.141; and the dominant model: OR = 1.46, 95% CI = 0.71-3.00, P = 0.299). In the subgroup analysis by ethnicity, we obtained the similar results.

Conclusions

We systematically investigate the association between MMP-3-1171 5A/6A polymorphism and RA susceptibility; however, the results show a lack of correlation. Considering the small sample size and the selection bias existed in some studies, further studies are needed to confirm the findings.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-376) contains supplementary material, which is available to authorized users.

Association of HLA-B27 genetic polymorphisms with ankylosing spondylitis susceptibility worldwide: a meta-analysis

OBJECTIVES

Many publications have evaluated the correlation between HLA-B27 polymorphisms and ankylosing spondylitis (AS), with conflicting results. We carried out this new meta-analysis in order to collect all the relevant studies to further clarify the association of HLA-B27 polymorphisms with AS susceptibility.

METHODS

Relevant published data were retrieved through Medline, PubMed, Web of Science, CNKI, and the Chinese BioMedical Literature Database on disc. The statistical analysis was conducted using Review Manager Version 5.0 and STATA 11.0. From these data, the odds ratio (OR) with a 95 % confidence interval (95 % CI) was calculated.

RESULTS

(1) A total of 38 studies, including 3,410 AS cases and 1,735 healthy controls, were collected in this meta-analysis. (2) Our results showed that B2704 was a risk factor but B2703, B2706, B2707, B2727, B2729, and B2747 may be protective factors for AS worldwide. (3) These subtypes, such as B2701, B2702, B2705, B2708-15, B2717-20, B2723-24, B2733, B2735, B2740, B2746, B2749, and B2767, showed no association with susceptibility to AS. There was a huge difference with previous reports for B2702 and B2705. (4) The B2702, B2704 and B2705 subtypes have existed high heterogeneity but no publication bias.

CONCLUSIONS

This meta-analysis in our study suggested that B2704 might be a potential risk factor, however, B2703, B2706, and B2707 might be potential protective factors of AS, especially in Asia.

An ex vivo study on immunohistochemical localization of MMP-7 and MMP-9 in temporomandibular joint discs with internal derangement

Internal derangement (ID) is among the most common disorders of the temporomandibular joint (TMJ). Previous research by our group highlighted a correlation between apoptosis and TMJ ID. Metalloproteinases (MMP)-7 and -9 have been shown to play an important role in extracellular matrix ECM) homeostasis and, through it, in joint disc remodelling. The immunohistochemical expression of MMP-7 and -9 was investigated in discs from patients with TMJ ID and from healthy donors and compared with the degree of histological tissue degeneration. The collagen fibre arrangement in pathological discs exhibited varying degrees of disruption. New vessels were consistently detected; endothelial cells from these vessels were immunolabelled with both MMP-7 and MMP-9. More or less intense MMP-7 and MMP-9 immunolabelling was detected in the cytoplasm of disc cells from all patients. MMP-7 and MMP-9 immunostaining was significantly different between pathological and normal discs and correlated with the extent of histopathological degeneration. MMP-7 and MMP-9 upregulation in discs from patients with TMJ ID demonstrates their involvement in disc damage in this disorder. A greater understanding of these processes could help identify ways to curb MMP overproduction without affecting their tissue remodelling action. The design of specific inhibitors for these MMPs would not only help to gain insights into the biological roles of MMPs, but would also aid in developing therapeutic interventions for diseases associated with abnormal ECM degradation.

MMP13 polymorphism decreases risk for dental caries

Recent evidence suggests that genetic studies may contribute to a better understanding of individual susceptibility to caries. Matrix metalloproteinases (MMPs) and their tissue inhibitors have been suggested to be involved in the caries process. The purpose of this study was to determine if polymorphisms in MMP2 (rs243865), MMP9 (rs17576), MMP13 (rs2252070), and TIMP2 (rs7501477) were associated with caries. Eligible unrelated children and adolescents were evaluated using a cross-sectional design. Data on oral health habits was obtained through a questionnaire and caries data was collected by clinical examination. Genotyping of the selected polymorphisms was carried out by real-time PCR. Allele and genotype frequencies were compared between individuals with and without caries experience. Of 505 subjects, 212 were caries-free and most subjects (61.2%) had mixed dentition. Allele frequency of MMP2, MMP13 and TIMP2 was different between caries-affected and caries-free individuals, with significant association for MMP13 (p = 0.004). Mutant allele carriers for MMP13 demonstrated a significantly decreased risk for caries (OR = 0.538, 95% CI 0.313-0.926); this result remained significant after adjustment for candidate genes, type of dentition and dietary factors. Allelic and genotype frequencies of the polymorphism in MMP9 were similar in caries-affected and caries-free individuals. Genetic variations in MMP13 may contribute to individual differences in caries susceptibility. Our findings reinforce that susceptibility to caries results from gene-environment interactions.

Association of cytokine and matrix metalloproteinase profiles with disease activity and function in ankylosing spondylitis

Introduction

The pathology of ankylosing spondylitis (AS) suggests that certain cytokines and matrix metalloproteinases (MMPs) might provide useful markers of disease activity. Serum levels of some cytokines and MMPs have been found to be elevated in active disease, but there is a general lack of information about biomarker profiles in AS and how these are related to disease activity and function. The purpose of this study was to investigate whether clinical measures of disease activity and function in AS are associated with particular profiles of circulating cytokines and MMPs.

Methods

Measurement of 30 cytokines, five MMPs and four tissue inhibitors of metalloproteinases was carried out using Luminex^® technology on a well-characterised population of AS patients (n = 157). The relationship between biomarker levels and measures of disease activity (Bath ankylosing spondylitis disease activity index (BASDAI)), function (Bath ankylosing spondylitis functional index) and global health (Bath ankylosing spondylitis global health) was investigated. Principal component analysis was used to reduce the large number of biomarkers to a smaller set of independent components, which were investigated for their association with clinical measures. Further analyses were carried out using hierarchical clustering, multiple regression or multivariate logistic regression.

Results

Principal component analysis identified eight clusters consisting of various combinations of cytokines and MMPs. The strongest association with the BASDAI was found with a component consisting of MMP-8, MMP-9, hepatocyte growth factor and CXCL8, and was independent of C-reactive protein levels. This component was also associated with current smoking. Hierarchical clustering revealed two distinct patient clusters that could be separated on the basis of MMP levels. The high MMP cluster was associated with increased C-reactive protein, the BASDAI and the Bath ankylosing spondylitis functional index.

Conclusions

A profile consisting of high levels of MMP-8, MMP-9, hepatocyte growth factor and CXCL8 is associated with increased disease activity in AS. High MMP levels are also associated with smoking and worse function in AS.

Matrix metalloproteinase-2 functional promoter polymorphism G1575A is associated with elevated circulatory MMP-2 levels and increased risk of cardiovascular disease in systemic lupus erythematosus patients

Matrix metalloproteinase-2 (MMP-2) is a zinc dependent endonuclease that degrades type IV collagen, the major structural component of basement membranes. MMP-2 functional promoter polymorphism G1575A affects circulating level of MMP-2 and may be considered an important genetic determinant of cardiovascular disease (CVD) in systemic lupus erythematosus (SLE) patients. In this study, association between MMP-2 1575A allele with serum MMP-2, neopterin and lipid-lipoprotein levels and with SLE and developing CVD was investigated. The present case-control study consisted of 109 SLE patients with and without CVD (mean age, 35.6 years) and 101 gender- and age-matched, unrelated, healthy controls (mean age, 37.1 years) from the population in the west of Iran. MMP-2 1575G/A polymorphism was detected by polymerase chain reaction (restriction fragment length polymorphism) PCR-RFLP, serum MMP-2, neopterin and lipid levels were determined by enzyme-linked immunosorbent assay (ELISA), high-performance liquid chromatography (HPLC) and enzyme assay, respectively. The presence of MMP-2 G1575A allele was found to be associated with SLE and developed CVD (OR = 1.78, p = 0.029 and OR = 3.43, p = 0.025, respectively). The SLE patients with MMP-2 A (G/A + A/A) allele had higher MMP-2 activity (301 ± 166 vs. 194 ± 35.5, p = 0.002), neopterin (29.4 ± 39.4 vs. 7.3 ± 4.6, p = 0.005), LDL-C (120 ± 25.7 vs. 87 ± 39.3, p = 0.045) and lower HDL-C (39.6 ± 11 vs. 45.9 ± 11.8, p = 0.031) levels than the control subjects. There was a significantly positive correlation between MMP-2 level with neopterin, total cholesterol and TG levels and negative correlation with HDL-C level in SLE patients with CVD. MMP-2 G1575A allele may be a risk factor for SLE. The carriers of this allele have high levels of MMP-2, neopterin, total cholesterol and TG and lower levels of HDL, thus, they are more likely to develop heart disease.

Variation of matrix metalloproteinase 1 and 3 haplotypes and their serum levels in patients with rheumatoid arthritis and osteoarthritis

The matrix metalloproteinases 1 and 3 (MMP1 and MMP3) are thought to be important in destructive joint changes seen in rheumatoid arthritis (RA) and osteoarthritis (OA) diseases. The aim of this study was to analyze whether functional polymorphisms in the promoter region of the MMP1 and MMP3 genes were associated with RA and OA. The MMP1 (-1607 1G/2G) and MMP3 (-1171 5A/6A) polymorphisms were screened by polymerase chain reaction-restriction fragment length polymorphism in 100 patients with (RA), 100 patients with (OA), and 100 controls. Serum MMP1 and MMP3 levels were measured by enzyme-linked immunosorbent assay. The results reported a significant difference between patients with OA and controls regarding allele distributions of MMP1 polymorphism, but not between patients with RA and controls. For MMP3 polymorphism, the 6A/6A genotype was significantly more frequent in patients with RA and OA than in controls. The haplotype 2G-6A, which carries the abnormal alleles, showed higher frequencies in the patients with RA and OA than in controls (28%, 30% and 8%, respectively). There were no significant differences in serum MMP1 and MMP3 levels between all studied groups. In conclusion, the MMP1 and MMP3 haplotypes may represent genetic determinants for RA and OA in the Egyptian population. The results suggest that MMP polymorphism genotypes may be more useful in predicting joint damage than measurement of serum concentrations of MMP1 and MMP3. Moreover, MMP1 and MMP3 polymorphisms may predict the activity and severity of these diseases.

Lymph node metastasis of gastric cancer is associated with the interaction between poly (ADP-ribose) polymerase 1 and matrix metallopeptidase 2

Poly (ADP-ribose) polymerase 1 (PARP1), which plays a critical role in the base excision DNA repair mechanism, and matrix metallopeptidase 2 (MMP2), a member of the matrix metalloprotease family, are involved in tumor formation and metastasis, respectively. In the present study, the possible association of single nucleotide polymorphisms (SNPs) and gene-gene interaction between PARP1 and MMP2 with the increased incidence of gastric cancer (GC) development and lymph node metastasis (LNM) was investigated in a Korean population. Samples were obtained from 326 patients with chronic gastritis and 153 patients with GC and genotyped using the GoldenGate® method. The PARP1 rs1136410 genotype showed a significant association with the frequency of LNM of GC (odds ratio [OR] = 2.19, p = 0.02), LNM stage (p = 0.035), and tumor invasion (p = 0.035). The allele frequency of MMP2 rs243865 was not associated with the development of GC or with the development of LNM of GC. Epistasis between the PARP1 SNP and the MMP2 SNP was associated with the development of LNM of GC. The combination of the MMP2 rs243865 CC genotype and the PARP1 rs1136410 CC or CC+CT genotypes showed a high risk of LNM of GC (OR = 2.47, p = 0.01; OR = 2.28, p = 0.01, respectively). In summary, PARP1 is associated with the risk of LNM of GC and the stage of LNM and tumor invasion. Epistasis between PARP1 rs1136410 and MMP2 rs243865 increased the risk of LNM of GC.

SERPINE1 intron polymorphisms affecting gene expression are associated with diffuse-type gastric cancer susceptibility

BACKGROUND

A primary inhibitor of plasminogen activators, SERPINE1 (serpin peptidase inhibitor 1, clade E, member 1, also known as plasminogen activator inhibitor type 1), is an important regulator in tumorigenesis and is highly expressed in many cancers.

METHODS

Five tag single nucleotide polymorphisms (SNPs) and 1 insertion polymorphism within SERPINE1 were genotyped in 1101 unrelated Korean individuals (a case group of 612 patients with gastric cancer and a control group of 489 healthy individuals). Associations with susceptibility to diffuse-type gastric cancer (DGC) and intestinal-type gastric cancer were assessed using multivariate logistic regression analyses adjusted for age and sex. Allelic differences in the contribution to gene expression were measured using luciferase assays.

RESULTS

SNP c.1162+162C>T (rs2227692) in intron 7 was associated with susceptibility to DGC but not with susceptibility to intestinal-type gastric cancer. The minor allele-carrying genotypes C/T and T/T had 1.6-fold greater odds of DGC than the C/C genotype (P = .00084). This SNP was linked to a repeat-number variation c.1162+604AAAG(11_17), a deletion (del) variation c.1162+664_1162+673del, and another SNP c.1162+859T>A (rs2070683) in intron 7 based on the sequencing of 5 patients and 5 controls. The risk haplotype of the 4 variations exhibited a 30% greater gene expression level than the nonrisk haplotype in luciferase reporter assays (P = .025). In contrast, DGC susceptibility was not associated with the c.-1969_-1968insG polymorphism (rs1799768) in the promoter, commonly known as 4G/5G, in which the minor 5G allele is less active in transcription than the major 4G allele.

CONCLUSIONS

An association between SERPINE1 and DGC susceptibility was observed with 4 correlated polymorphisms in intron 7 rather than the 4G/5G polymorphism in the promoter, although all polymorphisms affected gene expression.

Matrix metalloproteinase gene polymorphisms in patients with rheumatoid arthritis

Several genetic factors seem to be involved in the pathogenesis of rheumatoid arthritis (RA). The aim of this study was to analyze whether functional polymorphisms in the promoter region of the MMP-1, -3 and -9 genes were associated with RA. The study population comprises 110 RA patients and 100 healthy controls. The -1607 1G/2G MMP-1, -1171 5A/6A MMP-3, and -1562 C/T MMP-9 polymorphisms were analyzed. The frequency of the 5A allele of MMP-3 gene was significantly higher in the controls when compared with the RA patients (0.45 vs. 0.32, P < 0.01). No significant differences were observed in the allele frequencies for the MMP-1 and -9 polymorphisms between RA patients and controls. Individuals carrying MMP-3 5A allele have significant higher frequency of extra-articular manifestations and rheumatoid nodules than individuals homozygous for 6A allele (P < 0.05). The results presented in this study provide evidence of an association between the MMP-3 gene polymorphism and RA.

The contribution of genes to osteoarthritis

Osteoarthritis (OA) is the most prevalent form of arthritis in the elderly. A large body of evidence, including familial aggregation and classic twin studies, indicates that primary OA has a strong hereditary component that is likely polygenic in nature. Traits related to OA, such as longitudinal changes in cartilage volume and progression of radiographic features, are also under genetic control. In recent years several linkage analyses and candidate gene studies have been performed and unveiled some of the specific genes involved in disease risk, such as FRZB and GDF5. This article discusses the impact that future genome-wide association scans can have on our understanding of the pathogenesis of OA and on identifying individuals at high risk for developing severe OA.

The contribution of genes to osteoarthritis

Osteoarthritis (OA) is the most prevalent form of arthritis in the elderly. A large body of evidence, including familial aggregation and classic twin studies, indicates that primary OA has a strong hereditary component that is likely polygenic in nature. Furthermore, traits related to OA, such as longitudinal changes in cartilage volume and progression of radiographic features, are also under genetic control. In recent years, several linkage analysis and candidate gene studies have been performed and have unveiled some of the specific genes involved in disease risk, such as FRZB and GDF5. The authors discuss the impact that future genome-wide association scans can have on our understanding of the pathogenesis of OA and on identifying individuals at high risk for developing severe OA.

A broad analysis of IL1 polymorphism and rheumatoid arthritis

OBJECTIVE

It has been suggested that polymorphisms in IL1 are correlated with severe and/or erosive rheumatoid arthritis (RA), but the implicated alleles have differed among studies. The aim of this study was to perform a broad and well-powered search for association between allelic polymorphism in IL1A and IL1B and the susceptibility to or severity of RA.

METHODS

Key coding and regulatory regions in IL1A and IL1B were sequenced in 24 patients with RA, revealing 4 novel single-nucleotide polymorphisms (SNPs) in IL1B. These and a comprehensive set of 24 SNPs tagging most of the underlying genetic diversity were genotyped in 3 independent RA case-control sample sets and 1 longitudinal RA cohort, totaling 3,561 patients and 3,062 control subjects.

RESULTS

No fully significant associations were observed. Analysis of the discovery case-control sample sets indicated a potential association of IL1B promoter region SNPs with susceptibility to RA (for RA3/A, odds ratio [OR] 1.27, P = 0.0021) or with the incidence of radiographic erosions (for RA4/C, OR 1.56, P = 0.036), but these findings were not replicated in independent case-control samples. No association with rheumatoid factor, anti-cyclic citrullinated peptide, or the Disease Activity Score in 28 joints was found. None of the associations previously observed in other studies were replicated here.

CONCLUSION

In spite of a broad and highly powered study, we observed no robust, reproducible association between IL1A/B variants and the susceptibility to or severity of RA in white individuals of European descent. Our results provide evidence that, in the majority of cases, polymorphism in IL1A and IL1B is not a major contributor to genetic susceptibility to RA.

Matrix metalloproteases: underutilized targets for drug delivery

Pathophysiological molecules in the extracellular environment offer excellent targets that can be exploited for designing drug targeting systems. Matrix metalloproteases (MMPs) are a family of extracellular proteolytic enzymes that are characterized by their overexpression or overactivity in several pathologies. Over the last two decades, the MMP literature reveals heightened interest in the research involving MMP biology, pathology and targeting. This review describes various strategies that have been designed to utilize MMPs for targeting therapeutic entities. Key factors that need to be considered in the successful design of such systems have been identified based on the analyses of these strategies. Development of targeted drug delivery using MMPs has been steadily pursued; however, drug delivery efforts using these targets need to be intensified and focused to realize the clinical application of the fast developing fundamental MMP research.