Polymorphisms in the promoter regions of matrix metalloproteinases 1 and 3 and cancer risk: a meta-analysis of 50 case-control studies

Causal relationships between serum matrix metalloproteinases and estrogen receptor-negative breast cancer: a bidirectional mendelian randomization study

To better clarify the causal effects between matrix metalloproteinases (MMPs) and estrogen-receptor (ER)-negative breast cancer (BC), we investigated the bidirectional causal relationship between MMPs and ER-negative BC by mendelian randomization (MR) analysis. Summary statistic data of five MMPs were extracted from European participants in 13 cohorts. Data of ER-negative BC collected from one of genome-wide association studies of European ancestry was used as experimental datasets and another four ER-negative BC datasets were used as validation sets. Inverse variance weighted method was used for main MR analysis and sensitivity analysis was also conducted. Serum level of MMP-1 has negative effect on ER-negative BC (odds ratio = 0.92, P = 0.0008) but the latter one was not the cause of the former one, which was supported by validation sets. No bidirectional causal effect was detected between the other four types of MMPs and ER-negative BC (P > 0.05). Sensitivity analysis indicated robustness of the above results without remarkable bias. To conclude, serum MMP-1 may be a protective factor against ER-negative BC. No reciprocal causality was found between the other kinds of MMPs and ER-negative BC. MMP-1 was indicated as a biomarker for risk of ER-negative BC.

Association of Matrix Metalloproteinase (MMP) Gene Polymorphisms With Knee Osteoarthritis: A Review of the Literature

Progressive matrix metalloproteinase (MMP)-induced degradation of the extracellular matrix (ECM) of the articular cartilage is one of the major pathogenic osteoarthritis (OA) events. Several single nucleotide polymorphisms (SNPs) in genes encoding MMPs have been identified as affecting MMP expression, production, and enzymatic activity. This study systematically reviews the literature regarding the association between the SNPs of genes encoding MMPs and the risk of knee OA. An electronic search in the PubMed and Web of Science databases from conception to January 2021 was performed addressing studies relating MMPs genetic polymorphisms with the risk of knee OA. We included case-control studies that used validated genotyping methods to detect the SNPs’ association in MMP genes with primary knee OA risk. Ten studies were finally included in this systematic review, evaluating different SNPs in six MMP genes in terms of knee OA pathogenesis: MMP-1 (3 SNPs), MMP-2 (1 SNP), MMP-3 (9 SNPs), MMP-8 (10 SNPs), MMP-9 (6 SNPs), and MMP-13 (1 SNP). Among them, nine SNPs of four MMP genes have been associated with knee OA: (a) MMP-1 -1607 1G/2G (Turkish, Chinese), (b) MMP-3 rs650108, rs650108, rs520540, rs602128, rs679620 (Chinese), (c) MMP-8 rs1940475 and rs376520 (Finnish), and (d) MMP-13 77A/ (rs2252070) (Chinese). The present review summarizes all known SNPs of MMP genes related to a higher risk of knee OA. There are at least nine SNPs in four MMP genes associated with knee OA. No solid correlation between MMP genotype and knee OA phenotype exists. More high-quality studies and modern genetic testing methods are needed to fully elucidate the role of polymorphisms of MMP genes in knee OA pathogenesis.

Contribution of Matrix Metalloproteinase-1 Genotypes to Colorectal Cancer in Taiwan

BACKGROUND/AIM

Matrix metalloproteinase-1 is responsible for extracellular matrix regulation, and its genetic role in colorectal cancer (CRC) is unclear. The aim of the study was to investigate the contribution of Matrix metalloproteinase-1 genotypes to CRC risk in Taiwan.

MATERIALS AND METHODS

A total of 362 cases and 362 controls were included and their MMP-1 -1607 (rs1799705) genotypes were examined. The environmental factors and clinical-pathological records were also analyzed.

RESULTS

The genotypic frequency of MMP-1 rs1799750 were different between the CRC and control groups (p for trend=0.0083). 1G/2G and 1G/1G were associated with lower risk (p=0.0438 and 0.0030, adjusted OR=0.73 and 0.54, 95%CI=0.54-0.90 and 0.37-0.83). Among non-smokers, those with 1G/2G and 1G/1G genotypes were at 0.70- and 0.48-fold odds of having CRC. Among non-alcohol drinkers, people with 1G/2G and 1G/1G genotypes were at 0.71- and 0.54-fold odds. The 1G/1G genotype were statistically lower among CRC patients with lymph node metastasis (7.2%) than those without (19.0%).

CONCLUSION

The genotypes at MMP-1 rs1799705 play a role in determining susceptibility to CRC risk in Taiwan.

C/EBPβ Promotion of MMP3-Dependent Tumor Cell Invasion and Association with Metastasis in Colorectal Cancer

AIMS

Tumor metastasis is a significant obstacle to curing colorectal cancer (CRC). C/EBPβ is thought to play an important role in CRC invasion and metastasis. In this study, we assessed whether C/EBPβ-mediated tumor invasion was dependent on MMP3, the expression of which is upregulated by C/EBPβ. We then determined whether C/EBPβ upregulation was associated with MMP3 levels and metastatic status in human CRC patients.

MATERIALS AND METHODS

A total of 102 patients were recruited for this study. mRNA and protein levels of C/EBPβ and MMP3 in CRC cell lines and patient specimens were determined by reverse transcription-polymerase chain reaction and western blot, respectively. Tumor cell invasion was analyzed using an in vitro Matrigel Invasion Assay. The correlation between C/EBPβ and MMP3 expression was determined by Pearson's correlation analysis.

RESULTS

Both mRNA and protein levels of MMP3 were upregulated by C/EBPβ overexpression and downregulated by C/EBPβ siRNA in HCT116 CRC cell cultures. C/EBPβ-enhanced tumor cell invasion was inhibited by MMP3 siRNA. In human CRC patients, C/EBPβ levels were correlated with MMP3 levels and metastatic status.

CONCLUSIONS

C/EBPβ upregulation promoted tumor cell invasion in an MMP3-dependent manner in vitro and was associated with metastatic status in CRC.

Synergistic effect of collagenase-1 (MMP1), stromelysin-1 (MMP3) and gelatinase-B (MMP9) gene polymorphisms in breast cancer

Background

Extracellular matrix degradation by matrix metalloproteinases (MMPs) is an important mechanism involved in tumor invasion and metastasis. Genetic variations of MMPs have shown association with multiple cancers. The present study is focused to elucidate the association of MMP-1, 3 and 9 genetic variants with respect to epidemiological and clinicopathological variables by haplotype, LD, MDR, survival in silico analyses among South Indian women.

Material and methods

MMP3–1171 5A/6A and MMP9–1562 C/T SNPs were genotyped by Allele specific polymerase chain reaction and MMP1-1607 1G/2G polymorphism by restriction fragment length polymorphism assays respectively, in 300 BC patients and age-matched 300 healthy controls. Statistical analysis was performed using the SNPStats and SPSS software. Linkage disequilibrium and gene-gene interactions were performed using Haploview and MDR software respectively. Further, transcription factor binding sites in the promoter regions of SNPs under study were carried out using AliBaba2.1 software.

Results

We have observed an increased frequency of 2G-allele of MMP1, 6A-allele of MMP3 and T-allele of MMP9 (p<0.05) respectively in BC subjects. The 2G-6A haplotype (minor alleles of MMP-1 and MMP-3 respectively) has shown an increased susceptibility to BC. Further, MMP polymorphisms were associated with the clinical characteristics of BC patients such as steroid hormone receptor status, lymph node involvement and metastasis. SNP combinations were in perfect LD in controls. MDR analysis revealed a positive interaction between the SNPs. 5-years survival rate and cox-regression analysis showed a significant association with clinicopathological variables.

Conclusion

Our results suggest that MMP1–1607 1G/2G, MMP3–1171 5A/6A and MMP9–1562 C/T gene polymorphisms have synergistic effect on breast cancer. The interactions of MMPs clinical risk factors such as lymph node involvement has shown a strong correlation and might influence the 5-years survival rate, suggesting their potential role in the breast carcinogenesis.

MMP1 rs1799750 single nucleotide polymorphism and lung cancer risk: a meta-analysis

BACKGROUND

Numerous studies have investigated the association of matrix metalloproteinase 1 (MMP1) rs1799750 single nucleotide polymorphism with lung cancer susceptibility, but the findings are inconsistent. Therefore, we performed a meta-analysis to comprehensively evaluate any possible association.

METHODS

We searched publications from MEDLINE, EMBASE and CNKI databases which assessed links between the MMP1 rs1799750 polymorphism and lung cancer risk. We calculated the pooled odds ratio (OR) and its 95% confidence interval (95%CI) using either fixed-effects or random-effects models.

RESULTS

The meta-analysis was based on 9 publications encompassing 4,823 cases and 4,298 controls. The overall results suggested there was a significant association between the MMP1 rs1799750 polymorphism and lung cancer risk (1G vs. 2G: OR = 0.83, 95%CI = 0.73-0.94; 1G1G vs. 2G2G: OR = 0.73, 95%CI = 0.59-0.92; 1G1G vs. 1G2G/2G2G: OR = 0.87, 95%CI = 0.79-0.97; 1G1G/1G2G vs. 2G2G: OR = 0.78, 95%CI = 0.64-0.95). In the subgroup analysis by ethnicity, the association was still obvious in Asians (all P values < 0.05), but there was no association in Caucasians (all P values > 0.05).

CONCLUSIONS

The MMP1 rs1799750 polymorphism is associated with decreased lung cancer risk, and a race-specific effect may exist in this association.

Plasma matrix metalloproteinase 9 as an early surrogate biomarker of advanced colorectal neoplasia

INTRODUCTION

Matrix metalloproteinases (MMPs) are overexpressed at different stages of colorectal carcinogenesis and could serve as early surrogate biomarkers of colorectal neoplasia.

OBJECTIVE

To assess the utility of plasma MMP2 and MMP9 levels in the detection of advanced colorectal neoplasia and their correlation with tissue levels.

METHODS

We analysed blood and tissue samples from patients with non-advanced adenomas (n=25), advanced adenomas (n=25), colorectal cancer (n=25) and healthy controls (n=75). Plasma and tissue gelatinase levels were determined by Luminex XMAP technology and gelatin zymography. Receiver operating characteristic (ROC) curve analysis was used to calculate the optimum cut-off for the detection of advanced colorectal neoplasia.

RESULTS

Plasma MMP2 levels were similar between groups whatever the type of lesion. Plasma MMP9 levels were significantly higher in patients with neoplastic lesions than in healthy controls (median 292.3ng/ml vs. 139.08ng/ml, P<0.001). MMP9 levels were also higher in colorectal cancer than in non-advanced adenomas (median 314.6ng/ml vs. 274.3ng/ml, P=0.03). There was a significant correlation between plasma and tissue levels of MMP9 (r=0.5, P<0.001). The plasma MMP9 cut-off range with the highest diagnostic accuracy was between 173ng/ml and 204ng/ml (AUC=0.80 [95% CI: 0.72-0.86], P<0.001; sensitivity, 80-86% and specificity, 57-67%).

CONCLUSION

Plasma MMP9 could be a surrogate biomarker for the early detection of advanced colorectal neoplasia, although its diagnostic performance could be increased by combination with other biomarkers.

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 of MMP-1 -1607 1G/2G (rs1799750) polymorphism with primary knee osteoarthritis in the Greek population

Osteoarthritis is the most common form of arthritis with still unknown pathogenic etiology and considerable contribution of genetic factors. One of the mechanisms of cartilage degradation in osteoarthritis is enzymatic proteolysis of the extracellular matrix by metalloproteinases. MMP-1, produced by chondrocytes and synovial cells, is a major proteinase of the MMPs family. The present study aims at evaluating the association of MMP1 gene -1607 1G/2G (rs1799750) polymorphism with primary knee osteoarthritis in the Greek population. One hundred fifty five patients with primary symptomatic knee osteoarthritis participated in the study along with 139 controls. Genotypes were determined using PCR-RLFP technique. Allelic and genotypic frequencies were compared between both study groups. There was no significant association between MMP1 -1607 1G/2G polymorphism and knee osteoarthritis, in crude analysis; however, after multiple logistic regression analysis, 1G/2G was associated with reduced odds of knee osteoarthritis by 75% in males, compared to genotypes 1G/1G + 2G/2G, adjusting for age and BMI (adjusted OR: 0.25, 95% CI: 0.069, 0.910, p = 0.035). The present study shows that MMP1 -1607 1G/2G (rs1799750) polymorphism might be a risk factor for knee osteoarthritis susceptibility in the Greek population. Further investigations are needed to confirm this association in the pathogenesis of osteoarthritis.

The contribution of the genetic variations of the matrix metalloproteinase-1 gene to the genetic susceptibility of gastric cancer

Matrix metalloproteinase-1 (MMP-1), an interstitial collagenase, is responsible for the proteolytic degradation of basement membrane and extracellular matrix. MMP-1 plays a major role in the invasion of gastric cancer (GC). The role of the genetic polymorphisms in the functional regions of MMP-1 on the risk of GC remains unclear. To identify the markers that contribute to the genetic susceptibility to GC, we examined the potential association between GC and nine single-nucleotide polymorphisms (rs 1799750, rs 498186, rs 475007, rs 514921, rs 494379, rs 996999, rs 2071232, rs 1938901, and rs 2239008) of the MMP-1 gene using the MassARRAY system in this study. The participants enrolled in this study included 422 patients with GC and 428 healthy subjects as the healthy controls from a Chinese Han population. The analysis revealed a weak association between the rs 1799750 (in the promoter region) genotype distribution and GC (p=0.020). The frequency of the 2G allele was significantly higher in the patients with GC than in the healthy controls (p=0.005, odds ratio [OR]=1.324, 95% confidence interval [CI]: 1.087-1.613). Moreover, the patients with the 2G/2G genotype of rs 1799750 had a significantly increased risk of cancer invasion compared with patients with the 1G/1G+1G/2G genotype (p=0.001, OR=0.505, 95% CI: 0.331-0.771). Strong linkage disequilibrium was observed in three blocks (D'>0.9). Significantly, more C-2G haplotypes (block 3) (p=0.0005 after Bonferroni correction) were found in GC subjects. These findings point to a role for MMP-1 promoter polymorphism in GC among a Han Chinese population, and may be informative for future genetic or biological studies on GC.

Functional polymorphisms in the matrix metalloproteinase genes and their association with bladder cancer risk and recurrence: a mini-review

Molecular pathogenesis of muscle invasive bladder cancer and non-muscle invasive bladder cancer is incompletely elucidated. It is believed that matrix metalloproteinases, which are involved in the processes of uncontrolled extracellular matrix substrates degradation and participate in modulating the activity of a variety of non-matrix proteins, can contribute to carcinogenesis. Polymorphisms in the MMP genes associated with unique genomic changes in bladder cancer patients are still being investigated to discover direct links with pathophysiological mechanisms. Because of the functional polymorphisms in the MMP genes, which have a proven or likely effect on their protein expression, they could possibly affect the tumor process. The current mini-review synthesizes findings regarding the association of genetic polymorphisms in the MMP genes with bladder cancer risk and recurrence in patients. We discuss the current views on the feasibility of genetic polymorphisms in the MMP1, 2, 3, 7, 8, 9 and 12 genes as a risk, and prognostic markers for patients with bladder cancer. The majority of the research described in the present mini-review proves that the genetic polymorphism in the MMP1 (rs1799750) is the most widely studied, and suggests that the rare genotype, 2G2G, of that gene might show increased susceptibility for bladder cancer, especially among smokers. However, existing statistically significant associations between the genetic polymorphisms in the MMP genes and bladder cancer risk have not been clearly shown, and further studies are necessary in order to positively confirm them or dispel potential false hopes.

Association of matrix metalloproteinase-3 -1171(5A>6A) polymorphism with cancer risk: a meta-analysis of 41 studies

Background and Objective

Evidence has shown that matrix metalloproteinases-3 (MMP3) is important for cancer progression. Recent studies about the association between the -1171(5A>6A) polymorphism in MMP3 promoter region and cancer risk have yielded conflicting results.

Methodology/Principal Findings

We performed a meta-analysis of 41 studies including 11112 cases and 11091 controls to determine whether the -1171(5A>6A) polymorphism of MMP3 was associated with cancer risk. We assessed the strength of association and performed sub-group analyses by cancer types, ethnicity, smoking status, genotyping method, source of controls and sample size. The pooled results revealed that no significant association of the -1171(5A>6A) polymorphism with overall cancer risk in any of four models. Further sub-group analysis revealed that individuals with the 6A allele had lower risk of gastrointestinal cancer in two models: heterozygote comparison (6A/5A vs. 5A/5A: OR = 0.74, 95%CI: 0.60—0.91; I² = 1.9%), and dominant model (6A/6A+6A/5A vs. 5A/5A: OR = 0.77, 95%CI: 0.64—0.94; I² = 29.0%). Additionally, the associations were significant in Asian populations for three models: homozygote comparison (6A/6A vs. 5A/5A, OR = 0.68, 95%CI: 0.52—0.90; I² = 26.7%), heterozygote comparison (6A/5A vs. 5A/5A: OR = 0.75, 95%CI: 0.58—0.98; I² = 0.0%), and dominant model (6A/6A+6A/5A vs. 5A/5A: OR = 0.69, 95%CI: 0.54—0.88; I² = 0.5%). It was noteworthy that we had a contrary finding in non-smokers: the variant 6A/6A homozygote might statistically increase cancer risk compared with 6A/5A+5A/5A genotype (OR = 1.92, 95%CI: 1.25—2.96; I² = 72.7%).

Conclusion

This meta-analysis suggests that the -1171(5A>6A) polymorphism in MMP3 promoter region is not associated with overall cancer risk, but it may contribute to decreased cancer risk in Asian population when compared with Caucasian population and significantly reduce the risk of gastrointestinal cancer.

The association of matrix metalloproteinase-1 genetic polymorphism (-1607 1G>2G) with colorectal cancer: a meta-analysis

Several case-control studies on the relation between matrix metalloproteinase (MMP)-1 gene -1607 1G>2G polymorphism and colorectal cancer do not have similar conclusions. The previous two meta-analyses focusing on the same issue also were inconsistent. To further evaluate the relation between the MMP-l gene polymorphism and colorectal cancer, we selected eight case-control studies related to MMP-1 gene polymorphism and colorectal cancer by searching MEDLINE, Embase, CANCERLIT, American Association for Cancer Research, Chinese Biomedical Literature Database, Chinese CNKI, and Wanfang database. Q test and I (2) test were used to test the heterogeneity. We utilized the random effects model to calculate the odds ratio (OR), 95% confidence interval (CI), and the overall effect of P value using the RevMan 5.2 software. The present study included 1,403 patients with colorectal cancer and 1,754 healthy control subjects. Both -1607 2G/2G genotype carriers [OR = 1.59, 95 % CI (1.27-2.01); P < 0.001] and the -1607 2G allele carriers [OR = 1.26, 95% CI (1.05-1.51); P = 0.01] were found to have an increased risk of colorectal cancer. Therefore, we concluded that MMP-1 -1607 1G>2G polymorphism was associated with colorectal cancer.

Role of MUC20 overexpression as a predictor of recurrence and poor outcome in colorectal cancer

Background

Colorectal cancer (CRC) remains one of the most common cancers worldwide. We observed that MUC20 was significantly up-regulated in CRC patients with poor prognosis based on the microarray analysis. However, little is known about the role of MUC20 in CRC.

Methods

Microarray experiments were performed on the Affymetrix U133 plus 2.0 GeneChip Array. The protein and mRNA levels of MUC20 were examined by immunohistochemistry (IHC) and Real-Time quantitative PCR (RT-qPCR) in CRC tissues and adjacent noncancerous tissues (ANCT). ShRNA and overexpression plasmids were used to regulate MUC20 expression in CRC cell lines in vitro; wound healing, Transwell migration assays, and Western blotting were used to detect migration and invasion changes.

Results

MUC20 was one of the up-regulated genes in CRC patients with poor prognosis by microarray. Using IHC and RT-qPCR, we showed that MUC20 expression was significantly higher in CRC tissues than in ANCT (P < 0.05). We further showed that MUC20 overexpression was correlated with recurrence and poor outcome (P < 0.05). The Kaplan-Meier survival curves indicated that disease-free survival (DFS) and overall survival (OS) were significantly worse in CRC patients with MUC20 overexpression. The Cox multivariate analysis revealed that MUC20 overexpression and TNM stage were independent prognostic factors. Elevated expression of MUC20 in cells promoted migration and invasion, whereas ShRNA-mediated knockdown inhibited these processes. In addition, Western blotting demonstrated that MUC20-induced invasion was associated with MMP-2, MMP-3, and E-cadherin.

Conclusions

Cumulatively, MUC20 may serve as an important predictor of recurrence and poor outcome for CRC patients. MUC20 overexpression could enhance migration and invasion abilities of CRC cells. Translation of its roles into clinical practice will need further investigation and additional test validation.

Comparative study and meta-analysis of meta-analysis studies for the correlation of genomic markers with early cancer detection

A large number of common disorders, including cancer, have complex genetic traits, with multiple genetic and environmental components contributing to susceptibility. A literature search revealed that even among several meta-analyses, there were ambiguous results and conclusions. In the current study, we conducted a thorough meta-analysis gathering the published meta-analysis studies previously reported to correlate any random effect or predictive value of genome variations in certain genes for various types of cancer. The overall analysis was initially aimed to result in associations (1) among genes which when mutated lead to different types of cancer (e.g. common metabolic pathways) and (2) between groups of genes and types of cancer. We have meta-analysed 150 meta-analysis articles which included 4,474 studies, 2,452,510 cases and 3,091,626 controls (5,544,136 individuals in total) including various racial groups and other population groups (native Americans, Latinos, Aborigines, etc.). Our results were not only consistent with previously published literature but also depicted novel correlations of genes with new cancer types. Our analysis revealed a total of 17 gene-disease pairs that are affected and generated gene/disease clusters, many of which proved to be independent of the criteria used, which suggests that these clusters are biologically meaningful.

The behavior of matrix metalloproteinases and their inhibitors in colorectal cancer

Matrix metalloproteinases (MMPs) play an important role in the degradation of extracellular matrix components crucial for tumor growth, invasion and metastasis. MMPs are controlled by natural inhibitors called tissue inhibitors of metalloproteinases (TIMPs). We and others have demonstrated that MMPs and TIMPs are especially important in the process of tumor invasion, progression and the metastasis of colorectal cancer (CRC). It has been proposed that MMPs and TIMPs might play a part not only in tumor invasion and initiation of metastasis but also in carcinogenesis from colorectal adenomas. Several recent studies demonstrated that high preoperative serum or plasma MMP-2, MMP-9 and TIMP-1 antigen levels are strong predictive factors for poor prognosis in patients with CRC and their determination might be useful for identification of patients with higher risk for cancer recurrence. MMP-9 and TIMP-1 have significant potential tumor marker impact in CRC. Their diagnostic sensitivity is consistently higher than those of conventional biomarkers. The pharmacological targeting of CRC by the development of a new generation of selective inhibitors of MMPs, that is highly specific for certain MMPs, is a promising and challenging area for the future.

MMP1-1607(1G>2G) polymorphism and the risk of lung cancer in Lebanon

CONTEXT:

Matrix metalloproteinases (MMPs) are a family of enzymes that degrade various components of the extracellular matrix and are involved in the development and progression of cancer. Lung cancer is the most commonly diagnosed cancer in Lebanon. MMP1 is responsible for degrading stromal collagens, which enhance the ability of neoplastic cells to cross basal membrane of both the endothelium and the vascular endothelium. A recent meta-analysis has suggested that the MMP1-1607 2G allele may be associated with an increased risk for certain types of cancers.

AIM:

This study was undertaken to investigate the association between guanine insertion polymorphism in the MMP1 promoter and the susceptibility to lung cancer in the Lebanese population.

SETTINGS AND DESIGN:

This case-control study was conducted on 41 patients with lung cancer and 51 age-matched healthy controls, recruited from different regions of Lebanon.

METHODS:

Cases were histologically confirmed lung cancer patients obtained from different hospitals in Lebanon. Controls were healthy unrelated individuals with no history of cancer or genetic diseases. All subjects were genotyped for MMP1 -1607(1G>2G) polymorphism using polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP).

RESULTS:

No statistically significant differences were found when genotype and allele distribution of MMP1 -1607(1G>2G) polymorphism were compared between patients with lung cancer and controls [P= 0.6 by chi-squared test on a 3×2 contingency table; allelic P=0.61, OR (95% CI) = 1.18 (0.60-2.31)].

CONCLUSION:

Our data shows that MMP1 promoter polymorphism is not associated with lung cancer susceptibility in the Lebanese population.

Influence of single nucleotide polymorphisms in the MMP1 promoter region on cutaneous melanoma progression

Recently, we reported on the associations of seven single nucleotide polymorphisms (SNPs) in the promoter region of MMP1 gene with susceptibility to cutaneous melanoma (CM). Considering the reported correlation between MMP1 expression and melanoma progression, we hypothesized that these promoter SNPs might affect CM progression and prognosis. In this study, we examined the associations of seven SNPs with overall survival, as well as six clinicopathological factors in 754 patients with CM. After adjustment for 11 covariates, we observed significant associations of the SNP -422A>T (rs475007) with ulceration status (P=0.012), primary tumor thickness (P=0.040), and anatomic site (P=0.030). We also observed significant associations of the SNP -755T>G (rs498186) with ulceration status (P=0.038) and anatomic site (P=0.003). Two SNPs, -839G>A and -519A>G, were marginally associated with primary tumor thickness, ulceration status, and anatomic site. Furthermore, the frequency of haplotype 2G-G-G-A-A-G-T was higher in patients with ulceration (odds ratio=2.18, 95% confidence interval: 1.08-4.40, P=0.030) compared with those without ulceration. However, we did not find significant associations of these SNPs with overall survival and other clinical factors. As primary tumor thickness and ulceration status are two important indicators of tumor progression and have significant associations with melanoma prognosis, our results suggested that these promoter SNPs in MMP1 might have potential effects on melanoma progression and prognosis by influencing related clinical factors.

Genetic polymorphisms in MMP 2, 9 and 3 genes modify lung cancer risk and survival

Background

Matrix metalloproteases (MMPs) are proteolytic enzymes that contribute to all stages of tumour progression, including the later stages of invasion and metastasis. Genetic variants in the MMP genes may influence the biological function of these enzymes and change their role in carcinogenesis and progression. We have investigated the association between the -735 C/T, the -1171 5A/6A, and the -1562 C/T polymorphisms in the MMP2, MMP3 and MMP9 genes, respectively, and the risk and survival of lung cancer.

Methods

The case-control study includes 879 lung cancer patients and 803 controls from a Caucasian population in Spain (CAPUA study). Genotypes were determined by PCR-RFLP. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression. The Kaplan-Meier method, long-rank test and Cox's were used for the survival analysis.

Results

The MMP9 -1562 T/T genotype was associated with a statistically significant decreased risk of developing lung cancer (OR = 0.23; 95% CI: 0.06-0.85), whereas no association was found for the MMP2 -735 C/T and MMP3 -1171 5A/6A polymorphisms. The MMP2 -735 T/T genotype was statistically significantly associated with a decreased survival in non-small cell lung cancer (NSCLC) patients, identified as an independent prognosis factor of survival (hazard ratio (HR) = 1.79; 95% CI: 1.00-3.20). In contrast, no association was found between the MMP3 -1171 5A/6A and the MMP9 -1562 C/T polymorphisms and survival.

Conclusions

These findings support the hypothesis that the MMP9 -1562 C/T polymorphism is associated with a protective effect against the development of lung cancer and suggest that the MMP2 -735 C/T polymorphism modify the length of survival in NSCLC patients.

Single nucleotide polymorphisms of matrix metallopeptidase 3 and risk of gliomas in a Chinese Han population

Matrix metallopeptidases (MMPs) play an important role in central nervous system tumor growth, invasion and spreading. The currently available data provide clear evidence for the involvement of MMP3 in the pathophysiology of glioma. The study aims to explore the association of single nucleotide polymorphisms (SNPs) across the MMP3 gene with glioma risk. Three haplotype tagging and additional two promoter SNPs were genotyped among 766 glioma patients and 824 cancer-free controls from East China. None of these polymorphisms alone had a significant effect on risk of gliomas. However, when three promoter polymorphisms were evaluated together by the number of putative risk of genotypes (i.e., rs645419AA, 632478CA+AA, rs522616AA), a statistically significantly increased risk of gliomas was associated with the combined genotypes with two to three risk genotypes, compared with those with zero to one risk genotypes (adjusted odds ratio (OR) = 1.32; 95% confidence interval (CI) = 1.03-1.68). This increased risk was also more pronounced among adults (adjusted OR = 1.14, 95%CI = 1.02-1.27), males (adjusted OR = 1.19, 95%CI = 1.05-1.36), smokers (adjusted OR = 1.28, 95%CI = 1.07-1.52), subjects with no family history of cancer (adjusted OR = 1.21, 95%CI = 1.07-1.37), and patients with nonastrocytic gliomas (adjusted OR = 1.23, 95%CI = 1.06-1.43). In summary, our results suggest that any one of MMP3 variants may not have a substantial effect on glioma risk, but a joint effect of MMP3 promoter polymorphisms may contribute to risk of gliomas, particularly for adult gliomas.

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.

Single-nucleotide polymorphisms of matrix metalloproteinases and their inhibitors in gastrointestinal cancer

Matrix metalloproteinases (MMPs) are implicated in cancer development and progression and are associated with prognosis. Single-nucleotide polymorphisms (SNPs) of MMPs, most frequently located in the promoter region of the genes, have been shown to influence cancer susceptibility and/or progression. SNPs of MMP-1, -2, -3, -7, -8, -9, -12, -13 and -21 and of the tissue inhibitor of metalloproteinases (TIMPs) TIMP-1 and TIMP-2 have been studied in digestive tract tumors. The contribution of these polymorphisms to the cancer risk and prognosis of gastrointestinal tumors are reviewed in this paper.

Current evidence on the relationship between four polymorphisms in the matrix metalloproteinases (MMP) gene and breast cancer risk: a meta-analysis

The matrix metalloproteinases (MMP) can degrade various components of the extracellular matrix and its functional genetic polymorphisms may be associated with breast cancer risk. However, this relationship remains controversial. A meta-analysis was conducted in order to investigate the potential association between four polymorphisms in the MMP gene and breast cancer risk. A database search yielded a total of 9 studies involving 2,597 cases and 2,618 controls. Four polymorphisms were included in the meta-analysis: MMP-1 -1607 2G/1G (rs1799750), MMP-2 -1306 C/T (rs243865), MMP-3 -1171 6A/5A (rs3025058) and MMP-9 -1562 C/T (rs3918242). Crude odds ratios (OR) with 95% confidence intervals (CI) were used to assess the strength of association. When all the studies were pooled into the meta-analysis, we found that breast cancer cases had a significantly higher frequency of CC genotype (OR = 1.27, 95% CI = 1.10, 1.47; P = 0.001) and lower frequency of CT genotype (OR = 0.78, 95% CI = 0.67, 0.91; P = 0.001) of MMP-2. No significant difference was found in any genotype of MMP-1, MMP-3 or MMP-9. In conclusion, this meta-analysis suggested that MMP-2 -1306 C/T polymorphism may contribute to breast cancer susceptibility. More studies were needed especially in Asians in the future.

The Arg194Trp polymorphism in the XRCC1 gene and cancer risk in Chinese Mainland population: a meta-analysis

The Arg194Trp polymorphism in the X-ray repair cross-complementing group 1 (XRCC1) gene has been proved to be in association with cancer risk in Chinese Mainland population, but a large number of studies have reported inconclusive results. A more comprehensive and precise estimation of the relationship is needed to clear the way towards future studies. Thus, we performed a meta-analysis to analysis these associations. A total of 34 case-control studies in 34 articles were included in this meta-analysis. The results showed that the 194Trp/Trp homozygote had a 31% increased risk of cancer than 194Trp/Arg and 194Arg/Arg genotypes, OR was 1.31 and 95%CI was 1.13 to 1.53. In the subgroup analysis by cancer sites, the Arg194Trp polymorphism was associated with increased risks of lung cancer (OR = 1.27 and 95%CI: 1.07-1.50 for Trp/Trp versus Arg/Arg + Arg/Trp) and esophageal cancer (OR = 1.68 and 95%CI: 1.33-2.13 for Trp/Trp versus Arg/Arg + Arg/Trp). This meta-analysis suggested that the Arg194Trp polymorphism of the XRCC1 gene is a cancer susceptible factor among Chinese Mainland population. More intensive and deeper studies are needed to further reveal the mechanism between Arg194Trp polymorphisms of XRCC1 gene and cancer risks in Chinese Mainland population.

Phenotypic complexity, measurement bias, and poor phenotypic resolution contribute to the missing heritability problem in genetic association studies

BACKGROUND

The variance explained by genetic variants as identified in (genome-wide) genetic association studies is typically small compared to family-based heritability estimates. Explanations of this 'missing heritability' have been mainly genetic, such as genetic heterogeneity and complex (epi-)genetic mechanisms.

METHODOLOGY

We used comprehensive simulation studies to show that three phenotypic measurement issues also provide viable explanations of the missing heritability: phenotypic complexity, measurement bias, and phenotypic resolution. We identify the circumstances in which the use of phenotypic sum-scores and the presence of measurement bias lower the power to detect genetic variants. In addition, we show how the differential resolution of psychometric instruments (i.e., whether the instrument includes items that resolve individual differences in the normal range or in the clinical range of a phenotype) affects the power to detect genetic variants.

CONCLUSION

We conclude that careful phenotypic data modelling can improve the genetic signal, and thus the statistical power to identify genetic variants by 20-99%.

Meta-analysis of association between matrix metalloproteinases 2, 7 and 9 promoter polymorphisms and cancer risk

Matrix metalloproteinase (MMP) 2, MMP7 and MMP9 are important members of the MMP family. Four polymorphisms in the promoter region of these MMPs, which are MMP2 -1306 C>T, MMP2 -735 C>T, MMP7 -181 A>G and MMP9 -1562 C>T, have been reported to be functional and may contribute to genetic susceptibility to cancers. However, the associations between these polymorphisms and cancer risk remain inconclusive due to conflicting results from different case-control studies. To better evaluate the role of these polymorphisms in cancer development, we conducted a meta-analysis that included 51 studies, with more than 40,000 subjects. The results showed that under dominant genetic model, MMP2 -1306 T was associated with lower susceptibility to lung cancer [odds ratio (OR) = 0.50, 95% confidence interval (CI) 0.43-0.59, P(heterogeneity) = 0.147, I(2) = 44.1%], head and neck cancer (OR = 0.53, 95% CI 0.41-0.69, P(heterogeneity) = 0.974, I(2) = 0.0%) and oesophageal cancer (OR = 0.67, 95% CI 0.55-0.80, P(heterogeneity) = 0.593, I(2) = 0.0%); MMP2-735T was associated with lower risk in lung cancer (OR = 0.65, 95%CI 0.53-0.79, P(heterogeneity) = 0.42, I(2) = 0.0%) and oesophageal cancer (OR = 0.84, 95% CI 0.70-0.99, P(heterogeneity) = 0.206, I(2) = 37.4%); MMP7 -181 AG and GG genotype carriers had an increased gastric cancer risk (OR = 1.90, 95% CI 1.43-2.51, P(heterogeneity) = 0.992, I(2) = 0.0%) and MMP9 -1562 C>T was not associated with cancer risk in the whole group analysis (OR = 0.99, 95% CI 0.91-1.08, P(heterogeneity) = 0.419, I(2) = 3.0%) and subgroup analyses. In all, our meta-analysis suggests that MMP2 -1306 C>T, MMP2 -735 C>T and MMP7 -181 A>G may play allele-specific roles in cancer development, while MMP9 -1562 C>T may not be a major risk factor for most cancer types. Large case-control studies should be performed to clarify the possible roles of these four polymorphisms in different kinds of cancer in more detail.

Genetic polymorphisms of matrix metalloproteinases and their inhibitors in potentially malignant and malignant lesions of the head and neck

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteinases that are capable of cleaving all extra cellular matrix (ECM) substrates. Degradation of matrix is a key event in progression, invasion and metastasis of potentially malignant and malignant lesions of the head and neck. It might have an important polymorphic association at the promoter regions of several MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) and TIMP-2 (-418 G/C or C/C). Tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring inhibitors of MMPs, which inhibit the activity of MMPs and control the breakdown of ECM. Currently, many MMP inhibitors (MMPIs) are under development for treating different malignancies. Useful markers associated with molecular aggressiveness might have a role in prognostication of malignancies and to better recognize patient groups that need more antagonistic treatment options. Furthermore, the introduction of novel prognostic markers may also promote exclusively new treatment possibilities, and there is an obvious need to identify markers that could be used as selection criteria for novel therapies. The objective of this review is to discuss the molecular functions and polymorphic association of MMPs and TIMPs and the possible therapeutic aspects of these proteinases in potentially malignant and malignant head and neck lesions. So far, no promising drug target therapy has been developed for MMPs in the lesions of this region. In conclusion, further research is required for the development of their potential diagnostic and therapeutic possibilities.