Polymorphisms of matrix metalloproteinases 1, 2, 3 and 9 and susceptibility to lung, breast and colorectal cancer in over 30,000 subjects

Association of MMP1 gene polymorphisms with breast cancer risk: A narrative review

Background and Aims

Breast cancer is a multifactorial malignancy with different clinicopathological and molecular characteristics. It is the most frequent cancer in women in terms of both incidence and mortality. Matrix metallopeptidase 1 or MMP1 is a zinc-dependent endopeptidase associated with several physiological processes through the modification of the extracellular matrix and tumor microenvironment. However, previous results did not suggest any concluding remarks on the correlation between MMP1 gene polymorphisms and the risk of breast cancer.

Methods

A comprehensive literature search was performed in PubMed database to retrieve relevant articles and extract data from suitable ones. The literature written only in English was selected for this review.

Results

A total of 26 articles were included in the present narrative review. From the available studies, it is observed that MMP1 is upregulated in breast cancer tissues and found to be correlated with metastasis and invasion. The expression of MMP1 gene is mediated by numerous factors, including polymorphisms which act as a potential risk factor for the progression of breast cancer. To establish the correlation between genetic polymorphisms in MMP1 and the risk of breast cancer, several case-control studies, as well as genetic analyses, have been carried out in different ethnicities. The association of genetic polymorphisms in MMP1 with the risk and survival of breast cancer in different populations has been reviewed in this study. Moreover, the structural domain of MMP1 and the role of MMP1 in breast cancer metastasis and invasion are also discussed which will help to understand the potential impact of MMP1 as a genetic biomarker.

Conclusions

This review provides an overview of the MMP1 gene polymorphisms in breast cancer. However, we recommend future studies concentrating on combined analysis of multiple SNPs, gene-gene interactions, and analysis of epigenetics, proteomics, and posttranscriptional modifications that will provide the best outcome.

The multifaceted roles of matrix metalloproteinases in lung cancer

Background

Though the matrix metalloproteinases (MMPs) are widely investigated in lung cancer (LC), however, almost no review systematically clarify their multi-faced roles in LC.

Methods

We investigated the expression of MMPs and their effects on survival of patients with LC, the resistance mechanisms of MMPs in anti-tumor therapy, the regulatory networks of MMPs involved, the function of MMPs inducing CSCLs, MMPs-related tumor immunity, and effects of MMP polymorphisms on risk of LC.

Results

High expression of MMPs was mainly related to poor survival, high clinical stages and cancer metastasis. Role of MMPs in LC are multi-faced. MMPs are involved in drug resistance, induced CSCLs, participated in tumor immunity. Besides, MMPs polymorphisms may increase risk of LC.

Conclusions

MMPs might be promising targets to restore the anti-tumor immune response and enhance the killing function of nature immune cells in LC.

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.

Matrix Metalloproteinase Gene Polymorphisms Are Associated with Breast Cancer in the Caucasian Women of Russia

We conducted this study to explore the association between matrix metalloproteinase (MMP) gene polymorphisms and breast cancer (BC) risk in the Caucasian women of Russia. In total, 358 affected (BC) and 746 unaffected (cancer-free) women were included in this case-control retrospective study. From BC-related genes in previous studies, ten single nucleotide polymorphisms (SNPs) in five MMP genes (MMP1, 2, 3, 8, 9) were genotyped. The BC risk was calculated by logistic regression (to evaluate the SNPs’ independent effects) and model-based multifactor dimensionality reduction (MB-MDR) (to identify SNP−SNP interactions) methods. The allelic variants’ distribution of c.836 A > G (rs17576) and c. 1721 C > G (rs2250889) MMP9 was significantly different between BC and cancer-free women: for G minor alleles, these SNPs manifested disorder protective effects (OR 0.82 and OR 0.67−0.71, respectively, pperm ≤ 0.035). Eleven haplotypes of six SNPs MMP9 were involved in BC risk (nine haplotypes) and protective (two haplotypes) effects. All 10 SNPs of the MMP genes examined were associated with BC within the 13 SNP−SNP interaction simulated models, with a pivotal role of the two-locus (rs17577 × rs3918242) MMP9 epistatic interaction (defined as 1.81% BC entropy within more than 60% of the genetic models). Under in silico bioinformatics, BC susceptibility MMP polymorphic loci are located in functionally active genome regions and impact genes expression and splicing “regulators” in the mammary gland. The biological pathways of BC MMP candidate genes are mainly realized due to metalloendopeptidase activity and extracellular matrix organization (structure, disassembly, metabolic process, etc.). In conclusion, our data show that MMP gene polymorphisms are related to BC susceptibility in the Caucasian women of Russia.

Matrix Metalloproteinases as Biomarkers and Treatment Targets in Mesothelioma: A Systematic Review

Metalloproteinases (MMPs) have an important role in tissue remodeling and have been shown to have an effect on tumor progression, invasion, metastasis formation, and apoptosis in several tumors, including mesothelioma. Mesothelioma is a rare tumor arising from pleura and peritoneum and is frequently associated with asbestos exposure. We have performed a systematic search of PubMed.gov and ClinicalTrials.gov databases to retrieve and review three groups of studies: studies of MMPs expression in tumor tissue or body fluids in patients with mesothelioma, studies of MMPs genetic variability, and studies of MMPs as potential novel drug targets in mesothelioma. Several studies of MMPs in mesothelioma tissues reported a link between higher expression levels of commonly studied MMPs and clinical parameters, such as overall survival. Fewer studies have investigated genetic variability of MMP genes. Nevertheless, these studies suggested that certain genetic variants in MMP genes can have either protective or tumor-promoting effects on mesothelioma patients. MMPs have been also reported as novel drug targets, but so far no clinical trials of MMP inhibitors are registered in mesothelioma. In conclusion, MMPs play an important role in mesothelioma, but further studies are needed to elucidate the potentials of MMPs as biomarkers and drug targets in mesothelioma.

The MMP-1 Gene rs1799750 Polymorphism Is Associated with Breast Cancer Risk

Numerous studies investigating an association between the matrix metalloproteinase-1 (MMP-1) gene rs1799750 polymorphism and breast cancer (BC) risk have reported inconsistent results. Therefore, this meta-analysis was undertaken to obtain a more precise estimate of the possible association between this genetic locus and BC susceptibility. Methods: Eight eligible studies involving 3439 cases and 3517 controls were identified by searching the PubMed, Google, CNKI, and EMBASE databases systematically through October 1, 2020. Results: The MMP-1 rs1799750 polymorphism was associated with a reduced BC risk in the overall study population under the heterozygous model. Stratification analyses indicated that this association is strong in Asians. Conclusion: There is evidence of an association between the MMP-1 rs1799750 polymorphism and BC susceptibility, viewed as a decreased risk factor for BC. More extensive studies with more diverse ethnic populations are necessary to confirm these findings.

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Association between matrix metalloproteinase 9 polymorphisms and breast cancer risk: An updated meta-analysis and trial sequential analysis

BACKGROUND

Numerous studies have sought associations between matrix metalloproteinase 9 (MMP-9) polymorphisms and breast cancer risk. However, these studies have yielded conflicting results. Hence, we performed an updated meta-analysis to clarify the effects of four MMP-9 gene polymorphisms (rs3918242, rs2250889, rs3787268, and rs17576) on breast cancer risk.

METHODS

A comprehensive literature search for eligible studies was conducted in five electronic databases, including PubMed, Embase and Web of Science, up to March 1, 2020. Summary odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of associations in random-effects models. For the reduction of type I errors, a trial sequential analysis (TSA) was performed.

RESULTS

Twenty-one studies (8813 breast cancer cases and 9323 controls) were included in the quantitative analysis. For rs3918242, the overall ORs were significant under allelic comparison (OR _{A vs. G} = 1.34; 95% CI 1.03, 1.74, P = 0.028) and the recessive genetic model (OR _{AA vs. GG+GA} = 1.40; 95% CI 1.06, 1.84, P = 0.016). For rs2250889, the ORs were significant under homozygote comparison (OR _{GG vs. CC} = 2.57; 95% CI 1.22, 5.42, P = 0.013), heterozygote comparison (OR _{GC vs. CC} = 2.48; 95% CI 1.17, 5.23, P = 0.018), and the dominant genetic model (OR _{GG+GC vs. CC} = 2.53; 95% CI 1.23, 5.20, P = 0.012). No associations were observed for rs3787268 or rs17576. The subgroup analyses indicated that the risk effect of the rs3918242 A allele was observed only among Asians. TSA showed that the findings for rs3918242, rs3787268, and rs17576 were robust, but many more patients are needed before definitive conclusions can be made for rs2250889.

CONCLUSION

Our meta-analysis suggests that MMP-9 rs3918242, but not rs3787268 and rs17576 polymorphisms, may be risk factors for breast cancer. The effect of rs2250889 needs further confirmation with a larger sample size.

Association of matrix metalloproteinases 3 and 9 single nucleotide polymorphisms with breast cancer risk: A case-control study

Two single nucleotide polymorphisms (SNPs) of matrix metalloproteinase (MMPs) 3 and 9 are functionally implicated in the progression of various types of cancer, including breast cancer (BC). However, the roles of these SNPs remain controversial. In addition, they also vary between one population and another. Therefore, the present study aimed to investigate the possible association between MMP3-1171 5A/6A and MMP9-1562 CT SNPs and the risk of BC among Egyptians, and to elucidate the alteration of MMP3 and MMP9 gene expression in patients with BC. The present case-control study enrolled 162 patients with BC and 146 control subjects. Restriction fragment length polymorphism-PCR was performed for analysis of the selected SNPs, gene expression of MMP3 and MMP9 was also assessed in 50 patients and 50 control subjects by reverse transcription-quantitative PCR. The frequencies of 5A/6A genotype and 5A allele of MMP3 were significantly higher in patients with BC compared with in healthy subjects. On the other hand, the distributions of MMP9 genotypes and alleles were not significantly different among patients and healthy subjects. Compared with healthy subjects, the expression levels of the two genes were found to be upregulated in patients with BC. Therefore, the present study indicated that MMP3-1171 5A/6A SNP, not MMP9-1562 C>T SNP may be a risk factor for developing BC among Egyptian females.

Association between Expression of Tissue Inhibitors of Metalloproteinases-1, Matrix Metalloproteinase-2, and Matrix Metalloproteinase-9 Genes and Axillary Lymph Nodes Metastasis in Patients with Breast Cancer

Background

Certain enzymatic biomarkers such as matrix metalloproteinase (MMPs) are instrumental in the breast cancer. Hence, they are viewed as predictive biomarkers in the primary prognosis of this type of cancer. Furthermore, they enjoy a predictive value in the evaluation of the disease, recurrence of tumor, invasion of tumor cells to other areas as well as therapeutic outcomes. The present study aimed to determine the association between the expression of the three tissue inhibitors of metalloproteinases-1 (TIMP1), MMP2, and MMP9 genes and axillary lymph nodes involvement in patients with breast cancer.

Methods

Patients in this study were categorized into two groups, first with axillary lymph nodes involvement (as the case group) and second group without the involvement of axillary lymph nodes (as the control group) referred to Cancer Institute at Imam Khomeini Hospital in Tehran in 2016. The gene expression was assessed using the reverse transcription polymerase-chain reaction technique.

Results

There was no significant difference in the mRNA level of MMP2 and MMP9 genes between the cancer tissues with and without axillary lymph node metastasis in comparison with normal samples. However, the mRNA level of TIMP1 gene was considerably higher in the cancer tissue with axillary lymph node metastasis as compared to the samples without metastasis. In other words, the presence of axillary lymph node metastasis induced a 77.8-fold increase in mRNA expression when compared to condition without metastasis.

Conclusions

The expression of TIMP1 gene is strongly associated with axillary lymph node metastasis in breast cancer patients.

Role of MMP-2(-1306 C/T) and TIMP-2(-418G/C) Polymorphism in Chinese Han Patients with Acne Vulgaris

Acne is the most common chronic inflammatory skin diseases. Multiple factors, such as hormonal, environmental, immunological, and genetic factors, are thought to be involved in acne. However, genetic studies have yet to elucidate the full mechanism of acne. The aim of this study was to investigate the association of MMP-2 (-1306C/T) and TIMP-2 (-418G/C) polymorphisms with the risk of acne vulgaris in a Chinese Han population. We also analyzed the correlation of clinical parameters and family history in patients with acne vulgaris. This study included 251 acne patients and 121 age- and sex-matched healthy controls. Genomic DNA was extracted from peripheral blood, and genotyping was performed by PCR and DNA sequencing techniques. There is a significant correlation between the MMP-2 (-1306C/T) polymorphism and the acne vulgaris (P<0.001). Although no association was found between the TIMP-2 (-418G/C) polymorphism and the acne vulgaris, patients with the MMP-2 CT/TIMP-2 GG or GC allele are at higher risk of acne vulgaris. There is also a significant difference in the severity of the disease between acne vulgaris patients with and without family history (P<0.001). This study indicated that the MMP-2 (-1306C/T) polymorphism, in combination with the TIMP-2 (-418G/C) polymorphism, contributes to acne vulgaris susceptibility in the Chinese Han population.

Taiwanin E inhibits cell migration in human LoVo colon cancer cells by suppressing MMP-2/9 expression via p38 MAPK pathway

Taiwanin E is a natural compound which is structurally analogous to estrogen II and is abundantly found in Taiwania cryptomerioides. It has been previously reported for its anticancer effects; however, the pharmaceutical effect of Taiwanin E on Human LoVo colon cancer cells is not clear. In this study, we investigated the effects of Taiwanin E on metastasis and the associated mechanism of action on Human LoVo colon cancer cells with respect to the modulations in their cell migration and signaling pathways associated with migration. The results showed that Taiwanin E inhibited cell migration ability correlated with reduced expression and activity of MMP-2 and MMP-9. In addition, Taiwanin E induced activation of p38 through phosphorylation. Inhibition of p38α/β significantly abolished the effect of Taiwanin E on cell migration and MMP-2/-9 activity. Our results conclude that Taiwanin E inhibited cell migration chiefly via p38α MAPK pathway and in a lesser extend via p38β MAPK. The results elucidate the potential of the phytoestrogen natural compound Taiwanin E as a cancer therapeutic agent in inhibiting the cell migration. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 2021-2031, 2017.

Heterologous Matrix Metalloproteinase Gene Promoter Activity Allows In Vivo Real-time Imaging of Bleomycin-Induced Lung Fibrosis in Transiently Transgenized Mice

Idiopathic pulmonary fibrosis is a very common interstitial lung disease derived from chronic inflammatory insults, characterized by massive scar tissue deposition that causes the progressive loss of lung function and subsequent death for respiratory failure. Bleomycin is used as the standard agent to induce experimental pulmonary fibrosis in animal models for the study of its pathogenesis. However, to visualize the establishment of lung fibrosis after treatment, the animal sacrifice is necessary. Thus, the aim of this study was to avoid this limitation by using an innovative approach based on a double bleomycin treatment protocol, along with the in vivo images analysis of bleomycin-treated mice. A reporter gene construct, containing the luciferase open reading frame under the matrix metalloproteinase-1 promoter control region, was tested on double bleomycin-treated mice to investigate, in real time, the correlation between bleomycin treatment, inflammation, tissue remodeling and fibrosis. Bioluminescence emitted by the lungs of bleomycin-treated mice, corroborated by fluorescent molecular tomography, successfully allowed real time monitoring of fibrosis establishment. The reporter gene technology experienced in this work could represent an advanced functional approach for real time non-invasive assessment of disease evolution during therapy, in a reliable and translational living animal model.

The association between MMP2 -1306 C > T (rs243865) polymorphism and risk of prostate cancer

BACKGROUND

Prostate cancer is the second most common cancer in men. Matrix metalloproteinase-2 (MMP2) is the most important member of the matrix metalloproteinase family. MMP2 digests the basement membrane and causes changes in the extracellular matrix which in turn facilitate cancer invasion. It, therefore, has a major role in tumor angiogenesis. Previous studies have identified a single-nucleotide polymorphism C/T at position -1306 of MMP2 gene promoter which is a key regulatory factor in cancer progression.

AIM

The present study aimed to determine the association between MMP2 polymorphism and the risk of prostate cancer in Iranian men.

METHODS

This case-control study was performed on 50 paraffin-embedded prostate cancer tissue samples and 54 blood samples from healthy men. Genotyping of the samples was performed using high-resolution melting analysis (HRM). Finally, 20 % of the genotypes were confirmed by sequencing.

RESULTS

No significant associations were found between CT and TT genotypes and the risk of prostate cancer. However, there were no significant relationships between the genotypes and the studied factors, e.g., age, pathological stage, and Gleason Score.

CONCLUSION

MMP2 -1306 C > T (rs243865) polymorphism was not significantly related with prostate cancer susceptibility in Iranian men.

Genetic Polymorphism of MMP2 Gene and Susceptibility to Prostate Cancer

BACKGROUND AND AIMS

The polymorphic genetic variants of matrix metalloproteinase (MMPs) can play critical roles in development and progression of cancer. The purpose of this study was to investigate if any association exists between MMP2 -1306/T and risk of prostate cancer (PCa).

METHODS

This case-control study comprised a total number of 241 subjects, including 102 patients with PCa and 139 controls with benign prostatic hyperplasia (BPH). MMP2 genotypes were detected by RFLP.

RESULTS

There is no significant difference between different genotypes of MMP2 polymorphism and risk of developing PCa (p = 0.08). Although these genotypes increased the risk of developing PCa 79% (CT vs. CC) and 54% (TT vs. CC), none had a significant effect (p = 0.09 and p = 1 respectively). There were no significant differences in genotype frequencies between patients with low and high degrees of PCa (p = 0.4). Therefore, this polymorphism cannot be considered as a protective factor for PCa metastasis. It seems that MMP2 polymorphism has no protective effect on the grading of the tumor (p = 0.8). Our results indicated that MMP2 polymorphism had no role in the vascular invasion of PCa.

CONCLUSION

We found no association between MMP2 polymorphism and cancer risk, overall or by grade, stage or age of diagnosis. Finally, there was no association between the different genotypes and PSA plasma levels among cases or controls. Further evaluations with larger samples from our population may illuminate the effects of polymorphisms on PCa risk and thus help early diagnosis, follow-up and prognostic determinations for PCa patients.

Relationship between single-nucleotide polymorphism of matrix metalloproteinase-2 gene and colorectal cancer and gastric cancer susceptibility: a meta-analysis

Background

Recently, the published data on the association between matrix metalloproteinase-2 (MMP-2) (C-1306T) polymorphism and colorectal cancer (CRC) and gastric cancer (GC) (gastrointestinal cancer) risk remained controversial. The aim of this study is to investigate the relationship between the risk of CRC and GC and single-nucleotide polymorphism of MMP-2(C-1306T).

Methods

Medline, Embase, Science Citation Index, and PubMed were thoroughly searched to identify relevant studies. Odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of the association.

Results

We performed a meta-analysis of 14 studies including 642 cases and 692 controls for CRC and 1,936 cases and 3,490 controls for GC. The result indicates that there is significant relationship between MMP-2(C-1306T) polymorphism and CRC risk in recessive model and codominant model (TT vs CC/CT: OR: 2.39, 95% CI: 1.30–4.37, P=0.005; TT vs CC: OR: 2.36, 95% CI: 1.29–4.34, P=0.006). In subgroup analysis according to ethnicity, significant associations were found in Caucasians (TT vs CC/CT: OR: 2.87, 95% CI: 1.43–5.78, P=0.003; TT vs CC: OR: 2.86, 95% CI: 1.41–5.80, P=0.003), but we did not find significant evidence with GC in all genetic models, and in stratified analysis according to ethnicity, no significant risk was found in the subgroup too.

Conclusion

This meta-analysis considered that the MMP-2(C-1306T) polymorphism is a risk factor for CRC susceptibility, especially in Caucasians, but it does not support any relationship to GC, and further studies are needed to explore the association.

Lack of association between the matrix metalloproteinase-2 -1306C>T polymorphism and breast cancer susceptibility: a meta-analysis

BACKGROUND

Since inconsistent results have been reported regarding the relation between the matrix metalloproteinase-2 (MMP-2) -1306C>T polymorphism and susceptibility for breast cancer, we performed a meta-analysis to investigate the issue.

MATERIALS AND METHODS

An internet search of PubMed and EMBASE was performed to identify eligible studies. Pooled odds ratios (ORs) with their corresponding confidence intervals (CIs) were calculated to evaluate any association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility.

RESULTS

Nine case-control studies were included in the meta-analysis, involving 9,858 cases and 10,871 controls. Overall, there was no evidence of any association between the MMP-2 -1306C>T polymorphism and breast cancer susceptibility in different genetic models (T-allele vs C-allele: OR=0.95, 95%CI, 0.82-1.10, p=0.49; TT vs CC: OR=1.03, 95%CI, 0.90-1.19, p=0.66; TT+TC vs CC: OR=0.93, 95%CI, 0.78-1.10, p=0.38; TT vs TC+CC: OR=1.02, 95%CI, 0.89-1.17, p=0.77). In the subgroup analysis by ethnicity, CC was associated with a significant increase in breast susceptibility among Latin-Americans in the dominant model (OR=0.61, 95%CI, 0.40-0.93, p=0.02), but the association disappeared in other models. No significant association was observed among Europeans, East Asians and others in different genetic models. In the subgroup analysis by their source of controls, no significant association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility was noted among population-based studies and hospital-based studies in different genetic models.

CONCLUSIONS

The results of this meta-analysis suggest that MMP-2 -1306C>T polymorphism is not associated with breast cancer susceptibility, although the association among Latin-Americans in the dominant model was significant.

Matrix metalloproteinase-9 -1562T allele and its combination with MMP-2 -735 C allele are risk factors for breast cancer

BACKGROUND

Expression of matrix metalloproteinases (MMPs) is up-regulated in human cancers. The aim of present study was to investigate the role of MMP-9 C-1562T polymorphism and its interaction with MMP- 2 C-735T polymorphism in susceptibility to breast cancer in a population from Western Iran with Kurdish ethnic background.

MATERIALS AND METHODS

The study sample of 205 individuals consisted of 101 breast cancer patients and 104 healthy subjects. MMP-9 C-1562T and MMP-2 C-735T variants were identified using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

RESULTS

Among 67.4% of studied patients the breast cancer developed in the third and forth decades of the life. The frequency of MMP-9 T allele was 17.3% in patients and 10.1% in controls. The presence of T allele significantly increased the risk of breast cancer by 1.87-fold [OR=1.87 (95% CI 1.05-3.33, p=0.035)]. The frequency of MMP-9 CT+TT genotype tended to be higher in those patients with a family history of cancer in first degree-relatives (36.8%) than those without a family history (28.3%, p=0.37). We observed an interaction between the MMP-9 -1562 T allele with MMP-2 -735 C allele that significantly increased the risk of breast cancer [OR=1.42 (95% CI 1.02- 1.98, p=0.036)].

CONCLUSIONS

The present study demonstrated that MMP-9 C-1562T polymorphism alone and in combination with MMP-2 C-735T polymorphism increased the risk of breast cancer that might be a useful biomarker in identifying women at risk of developing breast cancer. Also, this study revealed that in most women from Western Iran breast cancer presents in third and fourth decades of life.

Meta-analysis of associations between four polymorphisms in the matrix metalloproteinases gene and gastric cancer risk

BACKGROUND

Matrix metalloproteinases (MMPs) play important roles in pathogenesis and development of cancer. Recently, many studies have show associations between polymorphisms in the promoter regions of MMPs and risk of gastric cancer. The present meta-analysis was conducted in order to investigate the potential association between four polymorphisms in the MMP gene and gastric cancer risk.

METHODS

A computerized literature search was conducted in databases of Med-line, Embase, Science Citation Index and PubMed till June 2013 for any MMP genetic association study of gastric cancer. Odds ratios (ORs) and 95 % confidence intervals (CIs) were estimated for each gene under dominant and recessive models, and heterogeneity between studies was assessed using the Q test and I2 value. Overall and subgroup analyses according to ethnicity were carried out with Stata 12.0.

RESULTS

14 reports covering 8,146 patients (2,980 in the case group and 5,166 in the control group) were included in the present meta-analysis. We found that the MMP-7 (-181A>G) polymorphism increased the gastric cancer risk in therecessive model (GG vs. AA/AG, OR=1.768, 95% CI =1.153-2.712). For MMP2 ?1306 C>T, MMP1-1607 1G/2G, and MMP9?1 562 C>T, there were no associations between these polymorphisms and the risk of gastric cancer under dominant or recessive models.

CONCLUSION

This meta-analysis suggested that the MMP7-181 A>G polymorphism may contribute to gastric cancer susceptibility. More studies are needed, especially in Europeans, in the future.

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 between promoters polymorphisms of matrix metalloproteinases and risk of digestive cancers: a meta-analysis

PURPOSE

A variety of studies have been performed to elucidate the polymorphisms in promoter regions of matrix metalloproteinases (MMPs) associated with the risk of digestive cancers, and yet, results remain conflicting and heterogeneous. Thus, we undertook a systematic meta-analysis to determine the genetic susceptibility of MMPs to digestive cancers.

METHODS

A computerized literature search was conducted in databases of PubMed, Embase, and ISI Web of Knowledge till October 2012 for any MMP genetic association study in oral squamous, gastric, esophageal, and colorectal carcinomas. Odds ratios (OR) and 95 % confidence interval (CI) were estimated for each gene under dominant and recessive models, and the heterogeneity between studies was assessed using Q test and I (2) value. Overall and subgroup analysis according to anatomical sites and ethnicity was carried out. Statistical analysis was performed with Review Manager 5.0.

RESULTS

A total of 40 eligible publications with 68 comparisons were included in this study. For MMP1 nt-1607, individuals with 2G state could increase risk of digestive cancers in total analysis (dominant: OR = 1.31, 95 % CI = 1.16-1.48, P < 0.00001; recessive: OR = 1.29, 95 % CI = 1.11-1.50, P = 0.0009). In the subgroup of tumor sites, significant associations were also observed in esophageal cancer and colorectal cancer under both genetic models. For MMP2 nt-1306, CT or TT carriers performed significant protection against digestive cancer in the dominant model (OR = 0.69, 95 % CI = 0.55-0.85, P = 0.0007) of the overall. In the subgroup analysis, significant association was found in esophageal cancer, with borderline effects in gastric cancer and oral squamous cell carcinoma. For MMP7 -181 A/G, significant association was observed under two genetic models in the overall (dominant: OR = 1.26, 95 % CI = 1.10-1.43, P = 0.0009; recessive: OR = 1.33, 95 % CI = 1.11-1.60, P = 0.002) and in the individual cancer subgroup of esophageal cancer and gastric cancer. For MMP9 -1,562 C/T, a borderline effect was found with digestive cancers in the total and stratified analysis of the colorectal cancer under dominant model. No association was observed in either the overall or subgroup analysis for MMP3 -1,171 5A/6A.

CONCLUSIONS

Our meta-analysis demonstrated the fact that polymorphisms in promoter regions of MMP genes might be related to the susceptibility of digestive cancers, with cancer development for MMP1 and MMP7, and a protection against cancer for MMP2 and MMP9. Further evidences with adequate sample sizes need to be conducted.

Matrix metalloproteinase (MMP)-1 induces lung alveolar epithelial cell migration and proliferation, protects from apoptosis, and represses mitochondrial oxygen consumption

Idiopathic pulmonary fibrosis is a devastating lung disorder of unknown etiology. Although its pathogenesis is unclear, considerable evidence supports an important role of aberrantly activated alveolar epithelial cells (AECs), which produce a large variety of mediators, including several matrix metalloproteases (MMPs), which participate in fibroblast activation and lung remodeling. MMP-1 has been shown to be highly expressed in AECs from idiopathic pulmonary fibrosis lungs although its role is unknown. In this study, we explored the role of MMP-1 in several AECs functions. Mouse lung epithelial cells (MLE12) transfected with human Mmp-1 showed significantly increased cell growth and proliferation at 36 and 48 h of culture (p < 0.01). Also, MMP-1 promoted MLE12 cell migration through collagen I, accelerated wound closing, and protected cells from staurosporine- and bleomycin-induced apoptosis compared with mock cells (p < 0.01). MLE12 cells expressing human MMP-1 showed a significant repression of oxygen consumption ratio compared with the cells with the empty vector. As under hypoxic conditions hypoxia-inducible factor-1α (HIF-1α) mediates a transition from oxidative to glycolytic metabolism, we analyzed activation of HIF-1α. Ηigher activation of this factor was detected in MMP-1-transfected cells under normoxia and hypoxia. Likewise, a significant decrease of both total and mitochondrial reactive oxygen species was observed in MMP-1-transfected cells. Paralleling these findings, attenuation of MMP-1 expression by shRNA in A549 (human) AECs markedly reduced proliferation and migration (p < 0.01) and increased the oxygen consumption ratio. These findings indicate that epithelial expression of MMP-1 inhibits mitochondrial function, increases HIF-1α expression, decreases reactive oxygen species production, and contributes to a proliferative, migratory, and anti-apoptotic AEC phenotype.

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.

Matrix metalloproteinase genes are associated with breast cancer risk and survival: the Breast Cancer Health Disparities Study

Matrix metalloproteinases (MMPs) contribute to cancer through their involvement in cancer invasion and metastasis. We evaluated genetic variation in MMP1 (9 SNPs), MMP2 (8 SNPs), MMP3 (4 SNPs), and MMP9 (3 SNPs) and breast cancer risk among Hispanic (2111 cases, 2597 controls) and non-Hispanic white (NHW) (1481 cases, 1586 controls) women in the Breast Cancer Health Disparities Study. Ancestral informative markers (n = 104) were assessed to determine Native American (NA) ancestry. MMP1 [4 single nucleotide polymorphisms (SNPs)] and MMP2 (2 SNPs) were associated with breast cancer overall. MMP1 rs996999 had strongest associations among women with the most NA ancestry (OR 1.61,95% CI 1.09,2.40) as did MMP3 rs650108 (OR 1.36, 95% CI 1.05,1.75) and MMP9 rs3787268 (OR 1.52, 95% CI 1.09,2.13). The adaptive rank truncated product (ARTP) showed a significant pathway p_artp value of 0.04, with a stronger association among women with the most NA ancestry (p_artp = 0.02). Significant pathway genes using the ARTP were MMP1 for all women (p_artp = 0.02) and MMP9 for women with the most NA ancestry (p_artp = 0.024); MMP2 was borderline significant overall (p_artp = 0.06) and MMP1 and MMP3 were borderline significant for women with the most NA ancestry (p_artp = 0.07 and 0.06 respectively). MMP1 and MMP2 were associated with ER+/PR+ and ER+/PR-tumors; MMP3 and MMP9 were associated with ER−/PR− tumors. The pathway was highly significant with survival (p_artp = 0.0041) with MMP2 having the strongest gene association (p_artp = 0.0007). Our findings suggest that genetic variation in MMP genes influence breast cancer development and survival in this genetically admixed population.

Genetic variation in TLR or NFkappaB pathways and the risk of breast cancer: a case-control study

Background

Toll-like receptors (TLRs) and the transcription factor nuclear factor-κB (NFκB) are important in inflammation and cancer.

Methods

We examined the association between breast cancer risk and 233 tagging single nucleotide polymorphisms within 31 candidate genes involved in TLR or NFκB pathways. This population-based study in the Seattle area included 845 invasive breast cancer cases, diagnosed between 1997 and 1999, and 807 controls aged 65–79.

Results

Variant alleles in four genes were associated with breast cancer risk based on gene-level tests: MAP3K1, MMP9, TANK, and TLR9. These results were similar when the risk of breast cancer was examined within ductal and luminal subtypes. Subsequent exploratory pathway analyses using the GRASS algorithm found no associations for genes in TLR or NFκB pathways. Using publicly available CGEMS GWAS data to validate significant findings (N = 1,145 cases, N = 1,142 controls), rs889312 near MAP3K1 was confirmed to be associated with breast cancer risk (P = 0.04, OR 1.15, 95% CI 1.01–1.30). Further, two SNPs in TANK that were significant in our data, rs17705608 (P = 0.05) and rs7309 (P = 0.04), had similar risk estimates in the CGEMS data (rs17705608 OR 0.83, 95% CI 0.72–0.96; CGEMS OR 0.90, 95% CI 0.80–1.01 and rs7309 OR 0.83, 95% CI 0.73–0.95; CGEMS OR 0.91, 95% CI 0.81–1.02).

Conclusions

Our findings suggest plausible associations between breast cancer risk and genes in TLR or NFκB pathways. Given the few suggestive associations in our data and the compelling biologic rationale for an association between genetic variation in these pathways and breast cancer risk, further studies are warranted that examine these effects.

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.

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.

Progress in tumor vascular normalization for anticancer therapy: challenges and perspectives

Antitumor angiogenic therapy has been shown promising in the treatment of several advanced cancers since the approval of the first antiangiogenic drug Avastin in 2004. Although the current antiangiogenic drugs reduce the density of tumor blood vessels and result in tumor shrinkage at the early stage of treatment, recent studies have shown that antiangiogenic therapy has transient and insufficient efficacy, resulting in tumor recurrence in patients after several months of treatment. Blockage of blood and oxygen supplies creates a hypoxic and acidic microenvironment in the tumor tissues, which fosters tumor cells to become more aggressive and metastatic. In 2001, Jain proposed tumor vascular normalization as an alternative approach to treating cancers based on the pioneering work on tumor blood vessels by several other researchers. At present, normalizing the disorganized tumor vasculature, rather than disrupting or blocking them, has emerged as a new option for anticancer therapy. Preclinical and clinical data have shown that tumor vascular normalization using monoclonal antibodies, proteins, peptides, small molecules, and pericytes resulted in decreased tumor size and reduced metastasis. However, current tumor vascular normalizing drugs display moderate anticancer efficacy. Accumulated data have shown that a variety of vasculogenic/angiogenic tumor cells and genes play important roles in tumor neovascularization, growth, and metastasis. Therefore, multiple-targeting of vasculogenic tumor cells and genes may improve the efficacy of tumor vascular normalization. To this end, the combination of antiangiogenic drugs with tumor vascular normalizing therapeutics, as well as the integration of Western medicine with traditional Chinese medicine, may provide a good opportunity for discovering novel tumor vascular normalizing drugs for an effective anticancer therapy.

Association between polymorphisms in the promoter regions of matrix metalloproteinases (MMPs) and risk of cancer metastasis: a meta-analysis

BACKGROUND

A variety of studies have evaluated the associations between polymorphisms in the promoter regions of Matrix metalloproteinases (MMPs) and cancer metastasis. However, the results remain inconclusive. To better understand the roles of MMP polymorphisms in metastasis, we conducted a comprehensive meta-analysis.

METHODS

Electronic databases were searched (from January 2000 to June 2011) for any MMP genetic association studies in metastasis. Overall and subgroup analyses were performed. Odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the associations between MMP polymorphisms and metastasis. Statistical analysis was performed with Review Manager 5.0 and STATA11.0.

RESULTS

Thirty-three studies addressing five MMP polymorphisms were analyzed among 10,516 cancer cases (4,059 metastasis-positive cases and 6,457 metastasis-negative cases). For MMP1 (-1607)1G/2G, genotype 2G/2G increased the overall risk of metastasis under the recessive model (OR = 1.44, 95% CI = 1.05-1.98). In subgroup analysis based on cancer type, associations were found in head/neck and breast cancer under the recessive model, and also in breast cancer under the dominant model. For MMP3 (-1171) 5A/6A, the polymorphism decreased the overall risk of metastasis under two genetic models (recessive: OR = 0.80, 95%CI = 0.64-0.99, dominant: OR = 0.72, 95%CI = 0.56-0.93). The polymorphisms of MMP7 (-181) A/G and MMP9 (-1562) C/T increased metastatic risk. However, no association was observed between MMP2 (-1306) C/T and metastasis.

CONCLUSIONS

Our investigations demonstrate that polymorphisms in the promoter regions of MMP1, 3, 7 and 9 might be associated with metastasis in some cancers. Further studies with large sample size for MMP2 should be conducted.

Analysis of matrix metalloproteinase-1 gene polymorphisms and expression in benign and malignant breast tumors

A guanine insertion polymorphism in matrix metalloproteinase-1 promoter (MMP-1 2G) is linked to early onset and aggressiveness in cancer. We determined the role of MMP-1 2G on MMP-1 expression and breast cancer severity in patients with breast diseases. We observed no significant difference in genotype distribution among different disease groups. However, MMP-1 expression was significantly higher in atypical ductal hyperplasia than in benign breast disease and in invasive breast cancer compared to in situ breast cancer. MMP-1 2G insertion polymorphism in the invasive group also correlated significantly with the expression of MMP-1 and breast cancer prognostic markers HER2 and P53.

TLR4 protein contributes to cigarette smoke-induced matrix metalloproteinase-1 (MMP-1) expression in chronic obstructive pulmonary disease

Cigarette smoke is the major risk factor associated with the development of chronic obstructive pulmonary disease and alters expression of proteolytic enzymes that contribute to disease pathology. Previously, we reported that smoke exposure leads to the induction of matrix metalloproteinase-1 (MMP-1) through the activation of ERK1/2, which is critical to the development of emphysema. To date, the upstream signaling pathway by which cigarette smoke induces MMP-1 expression has been undefined. This study demonstrates that cigarette smoke mediates MMP-1 expression via activation of the TLR4 signaling cascade. In vitro cell culture studies demonstrated that cigarette smoke-induced MMP-1 was regulated by TLR4 via MyD88/IRAK1. Blockade of TLR4 or inhibition of IRAK1 prevented cigarette smoke induction of MMP-1. Mice exposed to acute levels of cigarette smoke exhibited increased TLR4 expression. To further confirm the in vivo relevance of this signaling pathway, rabbits exposed to acute cigarette smoke were found to have elevated TLR4 signaling and subsequent MMP-1 expression. Additionally, lungs from smokers exhibited elevated TLR4 and MMP-1 levels. Therefore, our data indicate that TLR4 signaling, through MyD88 and IRAK1, plays a predominant role in MMP-1 induction by cigarette smoke. The identification of the TLR4 pathway as a regulator of smoke-induced protease production presents a series of novel targets for future therapy in chronic obstructive pulmonary disease.

Matrix metalloproteinase pharmacogenomics in non-small-cell lung carcinoma

Non-small-cell lung carcinoma demonstrated considerable variability in its chemoresponse. However, the prospect of individualized medicine holds high hopes for improving patient survival. The study of tumor and patient genetic profiles, relative to drug-related genes, may offer new opportunities for tailoring treatments. Matrix metalloproteinases (MMPs) are zinc-containing endopeptidases, which degrade the extracellular matrix and basement membrane, and process bioactive mediators involved in promoting aspects of tumor growth. Polymorphisms in MMP genes known to influence the protein-expression patterns has been shown to influence therapy outcomes by altering signaling pathways. In this article, we address the polymorphic association of MMPs in response to chemotherapy in non-small-cell lung carcinoma. Advances in genome technology and their comprehensive and systematic deployment to elucidate the genomic basis of MMP differences promise to ultimately enhance the efficacy of chemotherapy while reducing its toxicity for the treatment of various cancers.

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.

Functional polymorphism of the MMP-1 promoter (-1607 1G/2G) in potentially malignant and malignant head and neck lesions in an Indian population

Matrix metalloproteinases (MMP) are a family of zinc-dependent proteases that degrade the entire component of the extracellular matrix. Our study explores the association of the MMP1 gene promoter (-1607 1G/2G) polymorphisms in oral submucous fibrosis (OSMF) and head and neck squamous cell carcinoma (HNSCC) in an Indian population. The MMP1 single-nucleotide polymorphism (SNP) was genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis in 412 patients with OSMF, 422 with HNSCC and 426 controls. Our results showed that the frequency of 1G/2G or 2G/2G promoter genotypes having the 2G allele is associated with higher enzymatic activity and significantly increases in OSMF (p<0.001) and HNSCC cases (p<0.00). In this study, results concluded that SNPs in the MMP1 promoter region may be associated with susceptibility to OSMF as well as HNSCC in an Indian population and addiction habits such as areca nut chewing and alcohol abuse may enhance the expression of the 2G allele of MMP1 genes in OSMF and HNSCC cases.

The EGF 61A/G polymorphism - a predictive marker for recurrence of liver metastases from colorectal cancer

BACKGROUND

Epidermal growth factor (EGF) plays an important role in tumorigenesis. Variations in the DNA sequence of the gene EGF can lead to alterations in EGF activity, which is suspected to influence tumor progression. This retrospective study aimed to investigate the influence of EGF 61A/G polymorphism on the recurrence of liver metastases after hepatic surgery in patients with colorectal cancer.

METHODS

EGF 61A/G polymorphism was determined in 268 consecutive patients (175 [65%] men and 93 [35%] women, mean age 62 +/- 10.3 years) who had liver metastases at primary diagnosis and were treated by surgery with curative intent (R0) for liver metastases from colorectal cancer.

RESULTS

Overall, 81 of 268 (30%) patients exhibited wild-type EGF 61 A/A, 137 (51%) were heterozygous EGF 61 A/G and 50 (19%) were homozygous EGF 61 G/G. After adjusting for age, sex, UICC stage and tumor location, we observed a trend-wise 1.6-fold increased risk for hepatic recurrence (HR 1.6; 95% CI 1.0-2.5, P = 0.06) in individuals with the G/G genotype compared with carriers of the A-allele. The effect was much more pronounced in younger patients (<or= 65 years), who showed a 2.0-fold increased risk of hepatic recurrence (HR 2.0; 95% CI 1.1-3.5, P = 0.021). No effect was observed in older patients (>or= 65 years). Interestingly, male patients with EGF G/G had a 1.6-fold higher risk of recurrence (HR 1.6; 95% CI 1.0-2.5, P = 0.07). A significant correlation (P = 0.033) was detected between Dukes classification and the homozygous 61 G/G genotype.

CONCLUSION

Despite the limitations of our study, the retrospective results indicate that carriers of the EGF polymorphism might be at higher risk of developing liver recurrences. If confirmed in subsequent studies, genotyping for the EGF A/G variant might help in identification of patients at high risk of recurrence of liver metastases.

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.