Genetic diversity in the matrix metalloproteinase family. Effects on function and disease progression

The association between genetic polymorphisms in matrix metalloproteinases and caries experience

OBJECTIVES

The variation in the caries susceptibility while environmental factors are similar indicates that the effect of individual factors such as genetics on caries process and tooth development should be revealed. The aim of this study was to evaluate the association between genetic polymorphisms in MMP13 (rs2252070) and MMP20 (rs1784418) with caries experience.

MATERIALS AND METHODS

A cross-sectional study was conducted on 200 subjects aged 6 to 14 years. Demographic data, data on oral health habits were obtained through the statements of guardian of the individuals, caries data was collected by clinical examination. Unstimulated whole saliva was collected to extract the genomic DNA. Genotyping of the selected polymorphisms was carried out by real-time PCR. Allele and genotype frequencies were compared between different subgroups considering caries experience. Data were analyzed using SPSS 16.0 by chi-square test and logistic regression analysis.

RESULTS

Allele distribution of MMP13 was different between caries-affected and caries-free subjects. MMP13 A allele increased the caries risk (p=0.005, OR=1.84, 95% CI 1.20-2.82). Allele and genotype distribution of the polymorphism in MMP20 were not associated with caries experience (p>0.05).

CONCLUSIONS

It is concluded that the genetic variation in MMP13 was associated with the caries experience in selected subjects in Turkey.

CLINICAL RELEVANCE

The knowledge regarding association between the MMP genes and caries experience, might benefit the clinical practice, improving caries-preventive and caries-therapeutic approaches.

Association of MMP-9 gene polymorphisms with acute coronary syndrome in the Uygur population of China

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) plays a pivotal role in early atherosclerosis, vascular remodeling and development of atherosclerotic lesion. The potentially functional MMP-9 gene polymorphism may contribute to the susceptibility of acute coronary syndrome (ACS). This study aimed to investigate the association between two single nucleotide polymorphisms (-1562C>T, R279Q) of the MMP-9 gene in patients with ACS in the Uygur population of China.

METHODS

This case-control study was composed of 361 ACS patients and 432 control subjects, who had undergone coronary angiography. Among the ACS patients, 162 (44.9%) had single-vessel disease, 145 (40.2%) had two-vessel disease, and 54 (14.9%) had three-vessel disease. The genotypes of the two selected SNPs were determined by the method of polymerase chain reaction and restriction fragment length polymorphism (RFLP-PCR). The relationship between the polymorphism of the MMP-9 gene and the severity of coronary arterial stenosis was analyzed.

RESULTS

Analysis of the two SNPs showed that the frequency of CT and TT genotypes in patients with ACS was significantly higher than that in the control group (ACS vs. controls; CT+TT: 25.5% vs. 15.8%, P=0.001). And the -1562 gene allele (C/T) was significantly associated with acute coronary syndrome (ACS vs. controls; C allele: 85.7% vs. 91.5%, T allele: 14.3% vs. 8.5%, P<0.001). But the frequencies of CT+TT and CC genotypes were not statistically different among ACS patients with one, two and three or more significantly diseased vessels (P=0.55). The R279Q polymorphism site with regard to the association with ACS was not significant (P>0.05). The presence of CT or TT genotypes, assuming codominant effect of the T allele, was independently associated with increased risk of coronary artery disease when adjustment was made for age, body mass index, smoking, hypertension and diabetes mellitus [odds ratio=1.737 (95% confidence interval, 1.337-2.257), P=0.018].

CONCLUSIONS

MMP-9-1562C>T polymorphism is associated with the susceptibility to ACS in the Uygur population of China. However, this mutation apparently is not related to the severity of coronary arterial stenosis. Another SNP (R279Q) polymorphism of MMP-9 is not significantly associated with the risk of ACS.

Association of genetic polymorphisms in matrix metalloproteinase-9 and coronary artery disease in the Chinese Han population: a case-control study

OBJECTIVE

Matrix metalloproteinase-9 (MMP-9) plays an important role in inflammation and matrix degradation involved in atherosclerosis and plaque rupture. The T allele of rs3918242 has been reported to lead to a high promoter activity and associate with the extent of coronary artery disease (CAD). And some studies have reported that the G allele of rs17576 might be associated with CAD. The aim of this study was to assess the association between the polymorphisms of the MMP-9 gene and CAD in the Chinese Han population.

METHODS

This case-control study comprised 258 CAD cases and 153 controls from the Chinese Han Population. The genomic DNA of MMP-9 was isolated from whole blood. Polymerase chain reaction-based restriction fragment length polymorphism was used to determine the rs3918242 and rs17576 genotypes in the MMP-9 gene and the total serum levels of MMP-9 were measured using enzyme-linked immunosorbent assay in both case and control groups.

RESULTS

Analysis of MMP-9 gene polymorphisms showed that the frequencies of the T allele and CT+TT genotypes of rs3918242 were significantly higher in the case group than in the control group (p<0.05). However, the distribution of variant genotypes of rs17576 did not differ between the case and control groups (p>0.05). The total serum level of MMP-9 was significantly higher in the case group than in the control group (p<0.05). The subjects carrying T alleles in the CAD group had higher average serum MMP-9 levels compared with CC genotypes (p<0.05).

CONCLUSIONS

Our results suggest that the single-nucleotide polymorphism of rs3918242 in the MMP-9 gene is associated with CAD and high serum levels of MMP-9 are also associated with CAD in the Chinese Han population. Therefore, genetic variation of rs3918242 may participate in the development of CAD through influencing MMP-9 expression.

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.

Matrix metalloproteinases

Remodeling of extracellular matrix is crucial for many physiological (cell migration, proliferation, growth, and development) and pathological (remodeling of heart, carcinogenesis, metastasis, etc.) events. Thus, the interaction between cells and extracellular matrix plays a key role in normal development and differentiation of organism and many pathological states as well. Changes in extracellular matrix are regulated by a system of proteolytic enzymes that are responsible for proteolysis of huge quantity of extracellular matrix components. Matrix metalloproteinases (MMPs) represent the main group of regulating proteases in ECM. Ability of matrix metalloproteinases to modify the structural integrity of tissues is essential for certain aspects of normal physiology and pathology. The ability to process molecules such as growth factors, receptors, adhesion molecules, other proteinases, and proteinase inhibitors makes MMPs potent controllers of physiological and pathological events in the cell microenvironment. Overactivation of MMPs has been implicated in numerous disease states.

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

OBJECTIVES

Matrix metalloproteinase 9 (MMP-9) plays a pivotal role in early atherosclerosis, vascular remodeling, and development of arterial plaque rupture. The potentially functional MMP-9 gene polymorphism may contribute to the susceptibility of myocardial infarction (MI). We aimed to investigate the association between the interaction of 2 single-nucleotide polymorphisms ([SNPs] -1562C>T and R279Q) of the MMP-9 gene and smoking with MI in a Uighur population of China.

METHODS

A case-control study composed of 384 coronary angiography proven patients with MI and 451 sex-matched and ethnically matched control participants were enrolled in the study. The genotypes of the 2 selected SNPs were determined by the method of polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP).

RESULTS

Analysis of 2 SNPs, the frequency of -1562 CT and TT genotypes in MI group was significantly higher than in control group (25.52% vs 17.29%; P = .004). And the -1562 T allele showed significant association with MI (MI vs controls: 14.19% vs 9.31%; P = .002). R279Q locus did not show significant differences between patients and controls ( P > .05). Multiple logistic regression analysis showed that -1562 T allele (CT or TT genotype; odds ratio [OR] 1.31, 95% confidence interval [CI] 1.22-1.40; P = .004), the interaction between -1562 T allele and smoking (OR 4.42, 95% CI 2.74-7.13; P < .001), and the interaction between 279 Q allele and smoking (OR 2.07, 95% CI: 1.04-4.13; P = .021) were independent risk factors for MI.

CONCLUSIONS

There findings suggest that MMP-9 -1562C>T polymorphism could be associated with the susceptibility to MI. Another SNP (R279Q) polymorphism was not significantly associated with MI. The -1562C>T or R279Q polymorphism of MMP-9 gene and smoking have a synergistic effect and are significantly associated with the risk of MI in Chinese Uighur population, respectively.

The collagenase-1 (MMP-1) gene promoter polymorphism - 1607/2G is associated with favourable prognosis in patients with colorectal cancer

Matrix metalloproteinase (MMP) overexpression has been implicated in the pathogenesis of colorectal carcinoma (CRC). Accumulating evidence suggests that MMP promoter single nucleotide polymorphisms (SNPs) effecting gene transcription are associated with enhanced susceptibility for the development of malignant disease, increased tumour invasiveness and poor patient survival. The aim of the current investigation was to determine whether such associations exist in a large CRC patient/control study population. Using an allelic discrimination real-time polymerase chain reaction, polymorphisms in the MMP-1, MMP-2 and MMP-3 gene promoters (−1607, −1306, and −1612 bp, respectively) were assessed in normal blood mononuclear cells from patients with CRC (n=503) and control subjects (n=471). Genotypes corresponding to each MMP SNP were correlated with tumour characteristics and clinical outcome. The frequency of each genotype was not statistically different between patients and control subjects and no significant differences were noted between the genotypes and tumour characteristics for the three MMP SNPs. CRC patients with the 2G/2G genotype for the MMP-1 SNP had significantly better 5-year survival compared to patients with a 1G allele (P<0.05). Our results demonstrate that CRC patients with a 2G/2G genotype in the MMP-1 gene promoter SNP have a favourable prognosis. Although our results were unexpected, given that this genotype is associated with enhanced MMP-1 transcriptional activity, they are consistent with recent data highlighting the anti-tumorigenic properties of MMPs.

Clinical implications of matrix metalloproteinases

Matrix metalloproteinases (MMPs) are a family of neutral proteinases that are important for normal development, wound healing, and a wide variety of pathological processes, including the spread of metastatic cancer cells, arthritic destruction of joints, atherosclerosis, pulmonary fibrosis, emphysema and neuroinflammation. In the central nervous system (CNS), MMPs have been shown to degrade components of the basal lamina, leading to disruption of the blood brain barrier and to contribute to the neuroinflammatory responses in many neurological diseases. Inhibition of MMPs have been shown to prevent progression of these diseases. Currently, certain MMP inhibitors have entered into clinical trials. A goal to the future should be to design selective synthetic inhibitors of MMPs that have minimum side effects. MMP inhibitors are designed in such a way that these can not only bind at the active site of the proteinases but also to have the characteristics to bind to other sites of MMPs which might be a promising route for therapy. To name a few: catechins, a component isolated from green tea; and Novastal, derived from extracts of shark cartilage are currently in clinical trials for the treatment of MMP-mediated diseases.

Premature coronary artery disease shows no evidence of linkage to loci encoding for tissue inhibitors of matrix metalloproteinases

Tissue inhibitors of metalloproteinases (TIMP1, TIMP2, TIMP3) are naturally occurring inhibitors of matrix metalloproteinases (MMPs). It has been proposed that MMPs have a role in weakening the fibrous cap and subsequent plaque rupture. We hypothesized that TIMP polymorphisms could predispose to premature coronary artery disease. As a first step, we examined the relevant loci using a linkage approach. Sibling pairs recruited for the British Heart Foundation (BHF) Family Heart Study with premature coronary artery disease were examined. Two to three microsatellite markers were examined per TIMP gene. These markers were either intragenic or very close to the locus encoding for the gene. Products were analyzed by capillary gel electrophoresis. Single and multipoint linkage analysis based on the likelihood ratio test was performed using SPLINK and Mapmaker/Sibs software; 417 families were genotyped consisting of 385 sibling pairs, 27 trios, and five sets of four siblings. We were unable to detect linkage of premature coronary artery disease to loci encoding for TIMP1-3. Polymorphisms of the tissue inhibitors of MMP genes do not predispose to premature coronary artery disease in an epidemiologically significant way.

Stress-related modulation of matrix metalloproteinase expression

Matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs), whose expression can be controlled by cytokines, play a role in extracellular matrix remodeling in physiological and pathological processes. Using a blister chamber wound model on UV-B-exposed human forearm skin, we examined whether stress or mood-associated neuroendocrine alteration is sufficient to modulate MMP and TIMP expression. We did not find evidence that depressive symptoms were reliably associated with modulation of either MMP or TIMP expression. However, we did find that activation of the hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal medullary (SAM) axes can modulate levels of MMPs. A positive association between plasma norepinephrine levels and MMP-2 protein levels, and a negative correlation between plasma cortisol levels and MMP-2 levels were found. The data suggest that activation of the HPA and SAM axes, even in individuals within the normal range of depressive symptoms, could mediate MMP levels and wound healing in blister wounds.

MMP13 promoter polymorphism is associated with atherosclerosis in the abdominal aorta of young black males

Previous studies suggested that remodeling of connective tissue is important in progression of atherosclerosis. We investigated the importance of matrix metalloproteinase 13 (MMP13), in the pathogenesis of atherosclerosis using 995 samples from the Pathobiological Determinants of Atherosclerosis in Youth collection in an association study. We identified two new MMP13 promoter polymorphisms. The genotype for one of the MMP13 polymorphisms was associated with fibrous plaque (P=0.024) in black males. Immunohistochemistry using antibodies for MMP13 showed that MMP13 is expressed in all layers of the aorta. In-vitro transfection experiments with reporter gene constructs and electrophoretic mobility-shift assays showed that the MMP13 polymorphism was a functional variant. MMP13 is therefore, a genetic risk factor for extent of fibrous plaque in the abdominal aorta in young black males. Elucidation of the currently unknown mechanism of the MMP13 polymorphism's action may provide for pharmacological intervention to reduce the severity of atherosclerotic changes in susceptible individuals.

Pharmacogenetics of Lipid-lowering Therapies

Cardiovascular disease is associated with nonmodifiable risk factors such as age, gender, and genetic background, and with modifiable risk factors such as lipid concentrations. Lowering serum lipid levels has been demonstrated to slow the progression of, or even induce regression in, atherosclerosis. However, like any other drug treatment, the magnitude of plasma lipid responses to drug therapies varies considerably among individuals. Pharmacogenetics provides the experimental basis to understand the variability in response to drugs as a function of the individual genetic makeup. Information from small clinical trials reveals that several candidate genes may hold some promise in our quest to predict individual success to hypolipemic drug treatment. However, the current clinical relevance of this knowledge is quite limited due to the small effects observed for each of the genetic markers examined. Future progress in this area will be driven by studying gene-gene and gene-treatment interactions in much larger patient populations.

Matrix metalloproteinases in colorectal cancer

Matrix metalloproteinases (MMPs) appear to play a key role in the development and progression of human malignancies. MMPs mediate the destruction of the extracellular matrix, which is an important early step in tumor invasion and metastasis. Growing evidence suggests that MMPs also have angiogenic activity and participate in the early stages of tumorigenesis and primary tumor growth. Investigations in experimental animal models have confirmed the importance of MMPs in the pathogenesis of colorectal cancer, and studies in humans show a direct association between increased MMP expression and tumor invasiveness, development of metastases, and shortened survival. In this review, the physiologic role of MMPs in normal tissues is examined and data supporting the role of MMPs in the pathogenesis of colorectal cancer are reviewed. The results of clinical trials with MMP inhibitors in colorectal cancer and promising areas for future investigation are also discussed.

Candidate genes as potential links between periodontal and cardiovascular diseases

Recent epidemiological associations between periodontal disease and cardiovascular disease have led to a search for biological mechanisms that explain the associations. Genetic factors that influence biological processes involved in both diseases represent one of the potential mechanisms that may link periodontitis and cardiovascular disease. At present, several candidate genes have been investigated in one of the diseases but not the other. Although there are limited data to support a specific candidate gene as the explanation for observed associations between the 2 diseases, a few candidates look promising. One candidate that influences inflammation, interleukin-1 gene polymorphisms, has been associated with periodontal disease and cardiovascular disease. This review will consider biological mechanisms and genes that may be reasonable candidates for an etiological mechanism that influences the clinical characteristics of both periodontal disease and cardiovascular disease.

Analytical models of atherosclerosis

Atherosclerosis is responsible for approximately 50% of all mortalities in the USA, Europe, and Japan. An innovative approach for investigating atherosclerotic lesions using a thermodynamic model and a boundary value model and an analytical example of a human abdominal aorta vessel with an initial lesion are presented in the paper. Analytical results given by both models propose that increased transient boundary layer thickness and reduced surface energy of adhesion in regions of the arterial branch points play crucial roles in initial lesion formation. This study also improves the understanding of atherosclerotic mechanisms and helps to interpret clinical and experimental results.