Interaction between MMP-9 gene polymorphisms and smoking in relation to myocardial infarction in a Uighur population

Matrix metalloproteinases in coronary artery disease and myocardial infarction

Cardiovascular diseases (CVDs) remain the leading cause of death worldwide. Most cardiovascular deaths are caused by ischaemic heart diseases such as myocardial infarction (MI). Hereby atherosclerosis in the coronary arteries often precedes disease manifestation. Since tissue remodelling plays an important role in the development and progression of atherosclerosis as well as in outcome after MI, regulation of matrix metalloproteinases (MMPs) as the major ECM-degrading enzymes with diverse other functions is crucial. Here, we provide an overview of the expression profiles of MMPs in coronary artery and left ventricular tissue using publicly available data from whole tissue to single-cell resolution. To approach an association between MMP expression and the development and outcome of CVDs, we further review studies investigating polymorphisms in MMP genes since polymorphisms are known to have an impact on gene expression. This review therefore aims to shed light on the role of MMPs in atherosclerosis and MI by summarizing current knowledge from publically available datasets, human studies, and analyses of polymorphisms up to preclinical and clinical trials of pharmacological MMP inhibition.

Matrix Metalloproteinases in Cardioembolic Stroke: From Background to Complications

Matrix metalloproteinases (MMPs) are endopeptidases participating in physiological processes of the brain, maintaining the blood-brain barrier integrity and playing a critical role in cerebral ischemia. In the acute phase of stroke activity, the expression of MMPs increase and is associated with adverse effects, but in the post-stroke phase, MMPs contribute to the process of healing by remodeling tissue lesions. The imbalance between MMPs and their inhibitors results in excessive fibrosis associated with the enhanced risk of atrial fibrillation (AF), which is the main cause of cardioembolic strokes. MMPs activity disturbances were observed in the development of hypertension, diabetes, heart failure and vascular disease enclosed in CHA₂DS₂VASc score, the scale commonly used to evaluate the risk of thromboembolic complications risk in AF patients. MMPs involved in hemorrhagic complications of stroke and activated by reperfusion therapy may also worsen the stroke outcome. In the present review, we briefly summarize the role of MMPs in the ischemic stroke with particular consideration of the cardioembolic stroke and its complications. Moreover, we discuss the genetic background, regulation pathways, clinical risk factors and impact of MMPs on the clinical outcome.

Impact of MMP-9 Genetic Polymorphism and Concentration on the Development of Coronary Artery Disease in Ukrainian Population

Coronary artery disease (CAD) is one of the leading causes of death in Europe. It is known that atherosclerosis is the primary risk factor of CAD development. MMP-9 is involved in all stages of atherosclerosis and thus may contribute to CAD emergence. To investigate the influence of MMP-9 on the (CAD) development 25 patients with intact coronary arteries (CA), 40 patients with acute coronary syndrome (ACS), and 63 patients with chronic coronary syndrome (CCS) were enrolled in the study. Real-time PCR was carried out for genotyping on the rs17567-polymorphic locus, and ELISA study was performed to measure the MMP-9 plasma concentration. It was found the lower risk of MI occurrence for AG-carriers ( $P_a=0.023$ ; ORa = 0.299, 95% CI = 0.106–0.848) in Ukrainian population.

The Role of Matrix Metalloproteinase-9 in Atherosclerotic Plaque Instability

Matrix metalloproteinase-9 (MMP-9) belongs to the MMP family and has been widely investigated. Excessive MMP-9 expression can enhance extracellular matrix degradation and promote plaque instability. Studies have demonstrated that MMP-9 levels are higher in vulnerable plaques than in stable plaques. Additionally, several human studies have demonstrated that MMP-9 may be a predictor of atherosclerotic plaque instability and a risk factor for future adverse cardiovascular and cerebrovascular events. MMP-9 deficiency or blocking MMP-9 expression can inhibit plaque inflammation and prevent atherosclerotic plaque instability. All of these results suggest that MMP-9 may be a useful predictive biomarker for vulnerable atherosclerotic plaques, as well as a therapeutic target for preventing atherosclerotic plaque instability. In this review, we describe the structure, function, and regulation of MMP-9. We also discuss the role of MMP-9 in predicting and preventing atherosclerotic plaque instability.

The association between Matrix Metallo-proteinases-9 (MMP-9) gene family polymorphisms and risk of Coronary Artery Disease (CAD): a systematic review and meta-analysis

Background

We performed a systematic review and meta-analysis of the Matrix metalloproteinases (MMP)-9 (C1562T), MMP-9 (R279Q), MMP-9 (P574R) and MMP-9 (R668Q) polymorphisms and risk of Coronary Artery Disease (CAD).

Methods

After a systematic literature search, pooled odds ratio (OR) and their corresponding 95% confidence interval (CI) were used to evaluate the strength of the association.

Results

We identified 40 studies with 11,792 cases and 8280 controls for C1562T, 7 case-control studies with 5525 cases and 2497 controls for R279Q, 2 studies with 1272 cases and 785 controls for P574R, and 2 studies with 1272 cases and 785 controls for R668Q. MMP-9 (C1562T) polymorphism was associated with increased risk of CAD under dominant model (OR = 1.41, P < 0.001), recessive model (OR = 1.59, P < 0.001), allelic model (OR = 1.38, P < 0.001), TT vs. CC model (OR = 1.70, P < 0.001), and CT vs. CC model (OR = 1.35, P < 0.001). Moreover, the subgroup analysis based on the continent of the study populations in this SNP indicated strong significant association in Asians but not in Europeans. Subgroup analysis was not performed in Africa, America and Oceania, due to lack of sufficient data.

Conclusions

Our meta-analysis revealed that MMP-9 (C1562T) SNP conferred a susceptibility risk for CAD in the overall analysis and Asian population. The overall analysis and subgroup analysis of the other three SNPs reject the association between MMP-9 polymorphisms and the risk of CAD. Although the results should interpret with caution because of small sample size of included studies in these three SNPs.

Protective effects of fisetin against myocardial ischemia/reperfusion injury

The underlying mechanism of the myocardial protective effect of fisetin was studied in a rat ischemia/reperfusion injury model. Sprague-Dawley rats were randomly assigned to seven groups and pretreated with different solutions by gavage administration. A rat model of cardiac ischemia/reperfusion injury was established. Plasma levels of Von Willebrand factor (vWF) were determined by ELISA, flow cytometry was used to determine the level of cardiomyocyte apoptosis and 2,3,5-triphenyltetrazolium staining was used to determine the size of myocardial infarcts. Hematoxylin and eosin-stained sections of myocardial tissues were examined for pathological changes. Expressions of nuclear factor (NF)-κB and matrix metallopeptidase 9 (MMP-9) were measured by immunohistochemistry. Compared with the model group, rats pretreated with fisetin, quercetin and aspirin showed significant prolongation of clotting time, prothrombin time, thrombin time and activated partial thromboplastin time. Fisetin treatment better maintained the integrity of myocardial fibers and nuclear integrity, reduced the percentage of apoptotic myocardial cells, inhibited expression of NF-κB, decreased the loss of MMP-9 and reduced nuclear translocation of NF-kB. Rats pretreated with fisetin also demonstrated a significant decrease in plasma levels of vWF. In addition, the protective effect of fisetin on myocardial cells was found to be dose dependent.

No Association of Genetic Markers with Carotid Intimal Medial Thickness in β-Thalassemia Major Patients

Regular transfusion leads to cardiac siderosis resulting in cardiac complications that account for more than 71% of the total mortality in thalassemia patients. We aimed to study the variants of matrix metalloproteinase-9 (MMP9), matrix Gla protein (MGP), and estrogen receptor α(ERα), which might be contributing to atherosclerosis, leading to heart failure in thalassemia major. One hundred and five thalassemia patients on regular transfusion and iron chelation therapy were enrolled for the study. Carotid artery intimal medial thickness (CIMT) measurement was done to check for atherosclerosis. MMP 9 (C1562T), MGP (T138C), and ER α gene ( Pvu II (rs2234693T > C) and Xba I (rs9340799A > G) polymorphism were analyzed using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. CIMT values were within the normal range (<0.90 mm) in all patients. There was no difference in mean CIMT values between males and females (0.56 ± 0.11 versus 0.56 ± 0.12, p  = 0.928). There was no correlation of CIMT with age, body surface area, and body mass index as well as with serum ferritin levels. No statistically significant difference in frequency of MMP9, MGP, and ERα genotypes was seen in two dichotomized groups of CIMT (CIMT < 0.56 and CIMT ≥ 0.56). Variants of MMP9 , MGP , and ERα have a reserved influence on cardiac disease pathogenesis, and the disease phenotype in thalassemia patients may be more strongly impacted by other factors.

Association between matrix metalloproteinase 9 C-1562T polymorphism and the risk of coronary artery disease: an update systematic review and meta-analysis

Polymorphism (rs3918242) in the MMP9 gene has been reported to be associated with coronary artery disease (CAD). This study aims to investigate a more accurate estimation of the relationship between CAD and rs3918242 polymorphism by a meta-analysis method. We systematically searched studies on the association of rs3918242 polymorphism and CAD in PubMed, Web of Science, the Cochrane Library, Wanfang Data and CNKI. We used Stata 12.0 and RevMan 5.3 software to perform the meta-analyses. A total of 37 case-control studies involving 13,035 CAD patients and 11,372 non-CAD controls were included. A statistically significant association between rs3918242 polymorphism and CAD was observed in allelic model (Odds ratio (OR) 1.34; 95% confidence interval (CI) 1.20–1.50; p < 0.00001), recessive model (OR 1.43; 95% CI 1.17–1.75; p = 0.0004), and in dominant model ( OR 1.36; 95% CI 1.20–1.53; p < 0.00001). Moreover, we also found that there is a statistically significant association between rs3918242 polymorphism and myocardial infarction (MI) in Asians with allelic model (OR 1.66; 95% CI 1.29–2.14; p < 0.0001), recessive model (OR 2.29; 95% CI 1.44–3.63; p = 0.004), and dominant (OR 1.74; 95% CI 1.29–2.35; p = 0.0003) model. A similar result in Caucasians with allelic model (OR 1.14; 95% CI 1.02–1.27; p = 0.02), and in dominant (OR 1.17; 95% CI 1.04–1.32; p = 0.01) model. Our meta-analysis suggested that the MMP9 T allele is a risk factor for CAD and MI.

Association of R279Q and C1562T polymorphisms of matrix metalloproteinase 9 gene and increased risk for myocardial infarction in patients with premature coronary artery disease

BACKGROUND

A number of matrix metalloproteinase (MMP) gene polymorphisms has been identified which may be probably related to premature myocardial infarction (MI).

OBJECTIVE

We assessed the relationship between the two polymorphisms of the MMP9 gene including R279Q and C1562T and occurrence of premature MI.

METHODS

The study has two phases including a case-control study as the first phase and cohort study as the second phase. Initially, 1000 patients with premature coronary artery disease were classified into MI and non-MI groups. Genotyping of the polymorphism was conducted by PCRRFLP and high-resolution melting techniques. Given the two conditions of patients residing in Tehran and faced with their first episode of MI, 640 of 1000 study samples previously followed up with a median follow-up time of 45.74 months were assessed in a retrospective cohort phase regarding long-term major adverse cardiac events (MACE).

RESULTS

The prevalence of wild, heterozygous, and mutant genotypes of R279Q polymorphism in MI group was 14.5%, 57.3%, and 28.2% and in non-MI group was 36.9%, 38.4%, and 24.7%, respectively, with a considerable difference (P<.001). There was a significant difference in the prevalence of wild, heterozygous, and mutant genotypes of C1562T polymorphisms in MI group (12.4%, 41.2%, and 46.4%, respectively) and in non-MI group (46.8%, 38.6%, and 14.7%, respectively; P<.001). No difference was found in total MACE-free survival rate between genotypes of R279Q and C1562T polymorphisms.

CONCLUSION

C1562T and R279Q polymorphisms are associated with the susceptibility to premature MI, but cannot predict long-term cardiac events in these patients.

Matrix metalloproteinase-9 Gene-1562C>T Gene Polymorphism and Coronary Artery Disease in the Chinese Han Population: A Meta-Analysis of 5468 Subjects

BACKGROUND

Multiple studies indicate that the matrix metalloproteinase-9 (MMP-9)-1562C>T gene polymorphism may be associated with an increased risk of coronary artery disease (CAD) in the Chinese Han population. However, a clear consensus has yet to be established.

OBJECTIVE AND METHODS

A meta-analysis of 5468 subjects from 10 separate studies was performed to explore the possible relationship between the MMP-9-1562C>T gene polymorphism and CAD within the Chinese Han population. Pooled odds ratio (ORs) for the association and the corresponding 95% confidence intervals (CIs) were evaluated by a random or fixed-effect model.

RESULTS

Our analysis confirms the association between the MMP-9-1562C>T gene polymorphism and an increased risk of CAD within the Chinese Han population under allelic (OR: 1.60, 95% CI: 1.25-2.04, P = 0.0002), recessive (OR: 3.05, 95% CI: 1.67-5.56, P = 0.0003), dominant (OR: 2.23, 95% CI: 1.49-3.35, P = 0.0001), homozygous (OR: 3.41, 95% CI: 1.87-6.23, P < 0.0001), heterozygous (OR: 2.03, 95% CI: 1.40-2.93, P = 0.0002), and additive genetic models (OR: 1.78, 95% CI: 1.33-2.39, P < 0.0001).

CONCLUSIONS

In the Chinese Han population, the MMP-9-1562C>T gene polymorphism is correlated with an increased risk of CAD. Therefore, Han Chinese carriers of the -1562T allele may be at an increased risk of CAD.

MIF Gene Polymorphism rs755622 Is Associated With Coronary Artery Disease and Severity of Coronary Lesions in a Chinese Kazakh Population: A Case-Control Study

Inflammation plays an important role in the pathogenesis of atherosclerosis. Recent studies indicate that macrophage migration inhibitory factor (MIF) is a potent proinflammatory cytokine which mediates the inflammatory process during atherosclerosis. The polymorphism of MIF gene (rs755622 [-173G/C], rs1007888, and rs2096525) were genotyped by TaqMan single nucleotide polymorphism (SNP) genotyping assay in 320 patients with coronary artery disease (CAD) and 603 controls in a Chinese Kazakh population. Coronary angiography was performed on all CAD patients and Gensini score was used to assess the severity of coronary artery lesions. The frequency of the CC genotype and C allele of rs755622 were significantly higher in CAD patients than that in control subjects (8.4% vs. 5.1%, P < 0.001, 30.3% vs. 22.1%, P < 0.001, respectively). Multivariate logistic regression analysis showed that individuals with CC genotype or C allele had a higher risk for CAD (CC genotype vs. GG genotype, OR = 2.224, 95% CI, 1.239-3.992, P = 0.007, and C allele vs. G allele, OR = 1.473, 95% CI, 1.156-1.876, P = 0.002, respectively). Moreover, CAD patients with rs755622 C allele (CC + CG genotype) have higher levels of Gensini score when compared to C allele noncarriers (32.74 ± 26.66 vs. 21.44 ± 19.40, P < 0.001, adjusted). Our results suggested that the CC genotype and C allele of MIF rs755622 SNP may be a genetic marker for the risk of CAD and potentially predict the severity of CAD in Chinese Kazakh population.

Association of Matrix Metalloproteinase 9 C-1562T Polymorphism with Genetic Susceptibility to Myocardial Infarction: A Meta-Analysis

BACKGROUND

Myocardial infarction (MI) is the major cause of death by disease in the world. Many studies have identified the associations between matrix metalloproteinase 9 (MMP9) C-1562T polymorphisms and MI. However, the results remain inconclusive. To clarify the role of MMP9 C-1562T polymorphism in MI risk, we conducted a systematic review and large-scale meta-analysis.

METHODS

Studies published between January 2005 and March 2014 were obtained from the electronic databases PubMed, Medline, and Embase. The odds ratios (ORs) with 95% CIs were calculated for comparisons of the alleles and genotypes in the overall population and in ethnicity subgroups to measure the strength of genetic associations.

RESULTS

A total of 7 related studies, including 3952 MI cases and 4977 healthy control subjects were included in our meta-analysis. Our results show a statistically significant association between T allele and MI in the overall population (OR = 1.23; 95% CI, 1.02-1.48; P = 0.03). The risk of MI was also significantly higher in patients carrying the T allele (TC + TT genotypes) than in those with the CC genotype (P < 0.05). In stratified analysis by ethnicity, we found the T allele was strongly associated with MI in white populations, whereas in Asian populations there appeared no significant association.

CONCLUSIONS

Our data show that the MMP9 C-1562T polymorphism is a risk factor associated with increased MI susceptibility in the total population and white populations, although no significant association was observed in Asians populations. Further studies with larger sample sizes and assessing gene-gene and gene-environment interactions are required.

Matrix metalloproteinases in atherosclerosis: role of nitric oxide, hydrogen sulfide, homocysteine, and polymorphisms

Atherosclerosis is an inflammatory process that involves activation of matrix metalloproteinases (MMPs); MMPs degrade collagen and allow for smooth-muscle cell migration within a vessel. Moreover, this begets an accumulation of other cellular material, resulting in occlusion of the vessel and ischemic events to tissues in need of nutrients. Homocysteine has been shown to activate MMPs via an increase in oxidative stress and acting as a signaling molecule on receptors like the peroxisome proliferator activated receptor-γ and N-methyl-D-aspartate receptor. Nitric oxide has been shown to be beneficial in some cases of deactivating MMPs. However, in other cases, it has been shown to be harmful. Further studies are warranted on the scenarios that are beneficial versus destructive. Hydrogen sulfide (H₂S) has been shown to decrease MMP activities in all cases in the literature by acting as an antioxidant and vasodilator. Various MMP-knockout and gene-silencing models have been used to determine the function of the many different MMPs. This has allowed us to discern the role that each MMP has in promoting or alleviating pathological conditions. Furthermore, there has been some study into the MMP polymorphisms that exist in the population. The purpose of this review is to examine the role of MMPs and their polymorphisms on the development of atherosclerosis, with emphasis placed on pathways that involve nitric oxide, hydrogen sulfide, and homocysteine.

Association of matrix metalloproteinase-9 C1562T polymorphism and coronary artery disease: a meta-analysis

OBJECTIVE

Many investigations have studied the associations between matrix metalloproteinase-9 (MMP-9) C1562T polymorphisms and coronary artery disease (CAD). However, the conclusions of these studies were inconsistent. Therefore, this study was aimed at clarifying the association between MMP-9 C1562T polymorphisms and CAD in a large-scale meta-analysis.

METHODS

The PubMed and Embase databases were retrieved to collect all publications on the association between MMP-9 C1562T polymorphisms and CAD. Then the odd ratios (ORs) and 95% confidence intervals (95% CIs) for C1562T TT+TC versus CC genotype between CAD and the control groups were evaluated. Subgroup analysis was also performed according to different races. The meta-analysis was performed by Stata 10.0.

RESULTS

Sixteen case-control studies were included in our meta-analysis, involving 11032 CAD patients and 4628 non-CAD controls. Compared with C allele carriers, East Asian T allele carriers TT+TC had a significantly higher risk of CAD (OR=1.43; 95% CI: 1.03-1.99; P=0.031); however, there were no significant associations in Western populations (OR=1.06; 95% CI: 0.96-1.18; P=0.240) or West Asians (OR=1.13; 95% CI: 0.75-1.70; P=0.565). When further analyzing the association between C1562T polymorphisms and myocardial infarction (MI, the most serious type of CAD), the risk of TT+TC genotype versus CC genotype for MI was significantly higher for the overall (OR=1.21; 95% CI: 1.04-1.40; P=0.012) and for East Asians (OR=1.58; 95% CI: 1.26-1.97; P=0.000) but not in Western populations (OR=1.12; 95% CI: 0.99-1.26; P=0.078).

CONCLUSIONS

Our meta-analysis suggested an obvious ethnic difference in the association between MMP-9 C1562T polymorphisms and CAD. MMP-9 C1562T polymorphism was significantly related to CAD in East Asians. However, no significant associations were observed in either West Asians or Western populations.

Matrix metalloproteinases and genetic mouse models in cancer research: a mini-review

Carcinogenesis is a multistep and also a multifactorial process that involves agents like genetic and environmental factors. Matrix metalloproteinases (MMPs) are major proteolytic enzymes which are involved in cancer cell migration, invasion, and metastasis. Genetic variations in genes encoding the MMPs were shown in human studies to influence cancer risk and phenotypic features of a tumor. The complex role of MMPs seems to be important in the mechanism of carcinogenesis, but it is not well recognized. Rodent studies concentrated particularly on the better understanding of the biological functions of the MMPs and their impact on the pathological process, also through the modification of Mmp genes. This review presents current knowledge and the existing evidence on the importance of selected MMPs in genetic mouse models of cancer and human genetic association studies. Further, this work can be useful for scientists studying the role of the genetic impact of MMPs in carcinogenesis.

Association between -1562C>T polymorphism in the promoter region of matrix metalloproteinase-9 and coronary artery disease: a meta-analysis

AIMS

The present study was undertaken to determine the association between -1562C>T polymorphism in the promoter region of matrix metalloproteinase-9 (MMP-9) and coronary artery disease (CAD) risk.

METHODS

This meta-analysis was on the basis of 26 studies that included 12,776 cases and 6371 controls, heterogeneity of which was assessed by the Q-statistic test and the I(2)-statistic test. Sensitivity analysis was conducted by sequentially omitting any single study and recalculating the odds ratios (ORs) and 95% confidence intervals (CIs). Funnel plots and Egger's test were performed to test the potential publication bias. All data were analyzed by using STATA version 12.0.

RESULTS

We found that -1562C>T polymorphism did not contribute to the risk of CAD in the overall results. But the stratified analysis by ethnicity indicated that -1562C>T polymorphism might decrease susceptibility to CAD in Asians (OR, 0.94; 95% CI, 0.88-1.00; ph=0.956 for CC vs. CT+TT).

CONCLUSIONS

Our meta-analysis supports the fact that -1562C>T polymorphism may have association with CAD risk in Asian populations. But further larger studies are required to confirm our findings.

Matrix metalloproteinase-9: Many shades of function in cardiovascular disease

Matrix metalloproteinase (MMP)-9, one of the most widely investigated MMPs, regulates pathological remodeling processes that involve inflammation and fibrosis in cardiovascular disease. MMP-9 directly degrades extracellular matrix (ECM) proteins and activates cytokines and chemokines to regulate tissue remodeling. MMP-9 deletion or inhibition has proven overall beneficial in multiple animal models of cardiovascular disease. As such, MMP-9 expression and activity is a common end point measured. MMP-9 cell-specific overexpression, however, has also proven beneficial and highlights the fact that little information is available on the underlying mechanisms of MMP-9 function. In this review, we summarize our current understanding of MMP-9 physiology, including structure, regulation, activation, and downstream effects of increased MMP-9. We discuss MMP-9 roles during inflammation and fibrosis in cardiovascular disease. By concentrating on the substrates of MMP-9 and their roles in cardiovascular disease, we explore the overall function and discuss future directions on the translational potential of MMP-9 based therapies.

Matrix metalloproteinases in coronary artery disease

Matrix metalloproteinases (MMP) are a family of zinc-containing endoproteinases that degrade extracellular matrix (ECM) components. MMP have important roles in the development, physiology and pathology of cardiovascular system. Metalloproteases also play key roles in adverse cardiovascular remodeling, atherosclerotic plaque formation and plaque instability, vascular smooth muscle cell (SMC) migration and restenosis that lead to coronary artery disease (CAD), and progressive heart failure. The study of MMP in developing animal model cardiovascular systems has been helpful in deciphering numerous pathologic conditions in humans. Increased peripheral blood MMP-2 and MMP-9 in acute coronary syndrome (ACS) may be useful as noninvasive tests for detection of plaque vulnerability. MMP function can be modulated by certain pharmacological drugs that can be exploited for treatment of ACS. CAD is a polygenic disease and hundreds of genes contribute toward its predisposition. A large number of sequence variations in MMP genes have been identified. Case-control association studies have highlighted their potential association with CAD and its clinical manifestations. Although results thus far are inconsistent, meta-analysis has demonstrated that MMP-3 Glu45Lys and MMP-9 1562C/T gene polymorphisms were associated with CAD risk.

Meta-analysis of MMP9-562C/T and the risk of coronary heart disease

INTRODUCTION

Previous case-control studies have suggested that the -1562C/T and R279Q polymorphisms of the matrix metalloproteinase 9 gene (MMP9) are associated with coronary heart disease (CHD). However, other studies do not confirm these relationships. The objective is to assess these relationships using meta-analysis.

METHODS

Databases, including PubMed and ScienceDirect, were searched to access the genetic association studies. Then data were extracted. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated. Moreover, subgroup and sensitive analysis were performed.

RESULTS

The meta-analysis of the -1562C/T polymorphism included 12 studies with 8,336 cases and 3,984 controls. The -1562T allele was significantly associated with CHD (OR 1.25, 95% CI 1.08-1.45, p = 0.004). There was heterogeneity among the 12 studies (I2 = 61%, p = 0.003). The overall results were consistent and were not changed substantially by the removal of any data set. The meta-analysis of the R279Q polymorphism, including 6 studies with 6,983 cases and 3,282 controls, showed that the R279Q polymorphism was not associated with CHD (p = 0.16).

CONCLUSIONS

The synthesis of available evidence supports the fact that the MMP9 -1562C/T polymorphism is a risk factor for CHD.