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

Dietary patterns associated with benign breast nodules by subtypes: a cross-sectional study in southeast China

Background

Dietary patterns influence women's risk of breast cancer, but few studies have investigated the association with benign breast nodules, a well-established risk factor for breast cancer, especially by subtypes of the disease.

Methods

A cross-sectional study of 3,483 women enrolled in the Fuqing Cohort Study in southeast China was conducted from 2020 to 2021. Dietary patterns were identified from food frequency questionnaires using principal component analysis, and the scores for these patterns were divided into quartiles. Univariate and multivariate logistic regression models were used to calculate odds ratios (OR) with 95% confidence interval (CI) for the association between dietary patterns and benign breast nodules.

Results

We found four dietary patterns among the women: animal-based dietary pattern, plant-based dietary pattern, fried food/dessert pattern, and nuts pattern. Compared with the lowest quartile, women in the highest quartile of the scores for the animal-based dietary pattern were more likely to have cystic breast nodules (OR = 1.61, 95% CI = 1.12-2.32, and the P-value for trend test = 0.007), especially in postmenopausal women. In addition, women with a high score for fried food/dessert pattern also had higher odds of breast cystic nodules (P-value for trend test = 0.012), with an OR (95% CI) of 1.46 (1.01-2.09) for the fourth quartile group. However, there were no associations between these dietary patterns and solid breast nodules.

Conclusion

Animal-based dietary pattern and fried food/dessert pattern were positively associated with cystic breast nodules. These findings suggested the role of unhealthy dietary habits in the development of breast nodules.

Breast Cancer: Extracellular Matrix and Microbiome Interactions

Breast cancer represents the most prevalent form of cancer and the leading cause of cancer-related mortality among females worldwide. It has been reported that several risk factors contribute to the appearance and progression of this disease. Despite the advancements in breast cancer treatment, a significant portion of patients with distant metastases still experiences no cure. The extracellular matrix represents a potential target for enhanced serum biomarkers in breast cancer. Furthermore, extracellular matrix degradation and epithelial-mesenchymal transition constitute the primary stages of local invasion during tumorigenesis. Additionally, the microbiome has a potential influence on diverse physiological processes. It is emerging that microbial dysbiosis is a significant element in the development and progression of various cancers, including breast cancer. Thus, a better understanding of extracellular matrix and microbiome interactions could provide novel alternatives to breast cancer treatment and management. In this review, we summarize the current evidence regarding the intricate relationship between breast cancer with the extracellular matrix and the microbiome. We discuss the arising associations and future perspectives in this field.

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.

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.

The Role of Matrix Metalloproteinase Single-Nucleotide Polymorphisms in the Clinicopathological Properties of Breast Cancer

(1) Background. Breast cancer is the leading cancer type among women. Despite convenient diagnostics at early stages, there is a need for continuous monitoring to predict more aggressive or recurring breast cancer forms. The evidence suggests that the detection of genetic biomarkers could help in improving disease management and reduce mortality. Matrix metalloproteinases (MMPs) are a large family of enzymes that perform physiologically relevant functions and have the potential properties to be biomarkers for cancer assessment. We aimed to evaluate the contribution and association of single-nucleotide polymorphisms (SNPs) in MMP genes (MMP1, MMP2, MMP3, MMP7, MMP8, MMP9) with clinicopathological breast-cancer features. (2) Methods. In this study, 100 breast cancer patients were genotyped by polymerase chain reaction–restriction fragment length polymorphism methodology (PCR–RFLP). (3) Results. The presence of the MMP7 rs11568818 A allele was associated with lower chances for poorly differentiated breast cancer. The lower possibility for HER2-positive breast cancer was associated with the presence of the MMP9 rs3918242 C allele. (4) Conclusions. These results indicate that MMP7 rs11568818 and MMP9 rs3918242 are potential biomarkers for the anticipation of breast cancer aggressiveness.

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.

Dietary patterns and relative expression levels of PPAR-γ, VEGF-A and HIF-1α genes in benign breast diseases: case-control and consecutive case-series designs

We aimed to study dietary patterns in association with the relative expression levels of PPAR-γ, vascular endothelial growth factor-A (VEGF-A) and hypoxia-inducible factor-1α (HIF-1α) in women with benign breast disease (BBD). The study design was combinative, included a case-series and case-control compartments. Initially, eligible BBD patients (n 77, aged 19-52 years old) were recruited at Nour-Nejat hospital, Tabriz, Iran (2012-2014). A hospital-based group of healthy controls was matched for age (n 231, aged 20-63 years old) and sex. Dietary data were collected using a valid 136-item FFQ. Principal component analysis generated two main components (Kaiser-Meyer-Olkin = 0·684), including a Healthy pattern (whole bread, fruits, vegetables, vegetable oils, legumes, spices, seafood, low-fat meat, skinless poultry, low-fat dairy products, nuts and seeds) and a Western pattern (starchy foods, high-fat meat and poultry, high-fat dairy products, hydrogenated fat, fast food, salt and sweets). High adherence to the Western pattern increased the risk of BBD (ORadj 5·59; 95 % CI 2·06, 15·10; P < 0·01), whereas high intake of the Healthy pattern was associated with a 74 % lower risk of BBD (95 % CI 0·08, 0·81; P < 0·05). In the BBD population, the Western pattern was correlated with over-expression of HIF-1α (radj 0·309, P < 0·05). There were inverse correlations between the Healthy pattern and expressions of PPAR-γ (radj -0·338, P < 0·05), HIF-1α (radj -0·340, P < 0·05) and VEGF-A (radj -0·286, P < 0·05). In conclusion, new findings suggested that the Healthy pattern was associated inversely with the risk of BBD, and this could be correlated with down-regulation of PPAR-γ, VEGF-A and HIF-1α genes, which might hold promise to preclude BBD of malignant pathological transformation.

MMP-2 and MMP-9 gene polymorphisms act as biological indicators for ulinastatin efficacy in patients with severe acute pancreatitis

BACKGROUND

Severe acute pancreatitis (SAP) is a severe form of inflammatory disease with a high mortality rate. Ulinastatin, as a urinary trypsin inhibitor (UTI), is a glycoprotein playing a critical role in SAP. Consequently, we identified the hypothesis that both matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) gene polymorphisms might promote the efficacy of ulinastatin in SAP.

METHODS

A total of 235 patients with SAP were treated by intravenous drip of ulinastatin for the duration of 10 days. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed for testing the distribution of genotypes and alleles frequency of MMP-2 and MMP-9 gene polymorphisms, and analyzing association of MMP-2 rs243865, MMP-2 rs2285053, MMP-9 rs3918242, or MMP-9 rs17576 with efficacy of ulinastatin in patients with SAP. Shesis software was adopted for analyzing single genotypes of MMP-2 and MMP-9 gene polymorphisms site A Generalized Multifactor Dimensionality Reduction (GMDR) model and a logistic regression analysis were used for analyzing effect of MMP-2 and MMP-9 gene polymorphisms on the efficacy of ulinastatin in treating patients with SAP.

RESULTS

CC genotype of MMP-2 gene rs243865 C>T was observed to have a better positive effect in promoting the efficacy of ulinastatin in comparison with CT and TT genotypes. Haplotype CCTG, CCTA, CTTG, and CTTA were combined by MMP-2 and MMP-9 gene polymorphisms which have the ability to increase the efficacy of ulinastatin in treating patients with SAP. MMP-2 gene rs243865 C>T site polymorphism was served as a favorable factor while the MMP-9 gene rs3918242 C>T site polymorphism was noticed as an unfavorable factor for the efficacy of ulinastatin in treating patients with SAP.

CONCLUSION

The key findings clearly demonstrated that both the MMP-2 rs243865 and MMP-9 rs3918242 gene polymorphisms served as biological indicators for the efficacy of ulinastatin in treating patients with SAP.

Common matrix metalloproteinase-2 gene variants and altered susceptibility to breast cancer and associated features in Tunisian women

A role for matrix metalloproteinase polymorphisms in breast cancer development and progression was proposed, but with inconclusive results. We assessed the relation of matrix metalloproteinase-2 variants with breast cancer and related phenotypes in Tunisians. This case-control retrospective study involved 430 women with breast cancer and 498 healthy controls. Genotyping of matrix metalloproteinase-2 rs243866, rs243865, rs243864, and rs2285053 was analyzed by allelic exclusion. The minor allele frequency of rs2285053 was significantly lower in women with breast cancer cases as compared to control women; minor allele frequencies of the remaining single-nucleotide polymorphisms were similar between cases and control women. The distribution of rs243865 and rs2285053 genotypes was significantly different between breast cancer patients and control subjects. This persisted when key covariates were controlled for. None of the matrix metalloproteinase-2 variants were associated with estrogen receptor positivity, progesterone receptor positivity, or with double estrogen receptor–progesterone receptor positivity in breast cancer patients. Matrix metalloproteinase-2 rs243866, rs243865, and rs243864 were positively associated with menstrual irregularity and histological type, while rs243866 and rs2285053 were negatively associated with menarche and nodal status. In addition, rs2285053 was negatively associated with triple negativity, tumor size, distance metastasis, molecular type, and chemotherapy. Haploview analysis revealed high linkage disequilibrium between matrix metalloproteinase-2 variants. Four-locus Haploview analysis identified haplotypes GCTT and GTTC to be negatively associated with breast cancer, which remained statistically after controlling for key covariates. Matrix metalloproteinase-2 alleles and genotypes, along with four-locus haplotypes, are related to reduced susceptibility to breast cancer in Tunisian women, suggesting a protective effect.

A translational approach to the genetics of anxiety disorders

There have been important advances in our understanding of the genetic architecture of anxiety disorders. At the same time, relatively few genes have reached genome wide significance in anxiety disorders, and there is relatively little work on how exposure to an adverse environment impacts on gene expression in either animal models or human clinical populations. Here we assessed differential expression of genes of the dorsal striatum involved in synaptic transmission in an animal models of early adversity (maternal separation followed by restraint stress), and investigated whether variants in these genes were associated with risk for anxiety disorders, particularly in the presence of environmental stressors. Fifty-two male Sprague Dawley rats underwent maternal separation, and gene expression was studied using array technology. The human homologues of the differentially expressed genes were screened and analysed in a DSM-IV anxiety disorders cohort, and healthy controls (patients, n = 92; controls, n = 194), using blood. Two candidate genes (Mmp9 and Bdnf) were aberrantly expressed in the experimental rodent group relative to controls. Four single nucleotide polymorphisms (SNPs) in the human homologues of these genes were significantly associated with susceptibility for anxiety disorders (MMP9: rs3918242 and BDNF: rs6265, rs10835210 and rs11030107). Three of these (BDNF: rs6265, rs10835210, rs11030107) were found to interact significantly with childhood trauma severity resulting in increased likelihood of an anxiety disorder diagnosis. This study provides insights into the utility of rat models for identifying molecular candidates for anxiety disorders in humans.

MMP-7 A-181G Polymorphism in Breast Cancer Patients from Western Iran

BACKGROUND

Matrix metalloproteinases (MMPs) are upregulated in tumors. The MMP-7 A-181G polymorphism is associated with increased expression of the MMP-7 gene. Aim of the present study was to investigate the association between the MMP-7 A-181G polymorphism and susceptibility to breast cancer.

PATIENTS AND METHODS

The MMP-7 A-181G variants were studied in a cohort of 251 subjects consisting of 100 breast cancer patients and 151 healthy controls; all were from Western Iran. The MMP-7 A-181G genotypes were identified using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis.

RESULTS

The frequencies of the MMP-7 AA, AG, and GG genotypes in healthy individuals were 34.4, 50.4, and 15.2%, respectively. In breast cancer patients, the frequencies of AA (34%), AG (52%), and GG (14%) genotypes (p = 0.95) were similar to those in the controls. There was a trend toward an increased frequency of the combined genotype of MMP-7 AG+GG in patients with lymph node metastasis (70.4%) compared to those without metastasis (66.7%). Also, in patients with invasive lobular carcinoma, the frequency of the MMP-7 AG+GG genotype tended to be higher (71.4%) compared to that in patients with invasive ductal carcinoma (66.2%) (p = 0.78).

CONCLUSION

Our findings indicate that the MMP-7 A-181G polymorphism may not be correlated with susceptibility to breast cancer in our population.

The protective role of the -1306C>T functional polymorphism in matrix metalloproteinase-2 gene is associated with cervical cancer: implication of human papillomavirus infection

Cervical cancer is the major reproductive health problem among women caused by persistent infection of high-risk human papillomavirus (HR-HPV). Metalloproteinase-2 (MMP-2) is an endopeptidase highly expressed in cervical cancer; however, the genetic link between aberrant expression of MMP-2 and cervical carcinogenesis is not known. The genotypic distribution, expression pattern of MMP-2 and HPV infection, was analyzed in a total of 300 fresh surgically resected cervical tissue biopsies. The MMP-2 C1306T (rs243865) promoter polymorphism dominant model (CC v/s CT + CT + TT) revealed that the CC genotype had a 4.33-fold significant increased risk for development of cervical cancer (OR = 4.33; 95 % CI = 2.36-4.02, p = 0.0001) compared to those with variant genotypes (-1306 CT + TT). The C allele was associated with 3-fold significant increased risk (OR = 2.95; 95 % CI = 1.90-4.60, p = 0.0002) compared to T allele. Interestingly, a significant correlation was found between high expression of MMP-2 protein and CC genotype in cancer patients (p = 0.001) compared to normal controls (p = 0.012). Further analysis showed that the risk of cancer was extremely pronounced in HPV positive patients (OR = 9.33; 95 % CI = 2.88-30.20, p = 0.0001) compared to HPV negative ones, implicating the possible interaction between -1306CC genotype and HPV infection in increasing the cancer risk (p = 0.0001). The leads from the present study suggest the protective role of gene variant -1306C>T at the promoter region of the MMP-2 against HPV-mediated cervical cancer. These findings substantiate the functional role of MMP-2 C1306T polymorphism in a significant downregulation of MMP-2 protein in women with variant genotype (CT/TT) compared to the normal wild CC genotype.

Association between four MMP-9 polymorphisms and breast cancer risk: a meta-analysis

BACKGROUND

The role of matrix metalloproteinase 9 (MMP-9) polymorphisms in breast cancer risk remains unclear. The purpose of this study was to evaluate the association between MMP-9 variants and breast cancer susceptibility.

MATERIAL AND METHODS

Case-control studies were searched on electronic databases to retrieve related articles published between 2000 and 2014 concerning the role of MMP-9 variants in breast cancer risk. Pooled odds ratios (OR) with correlative 95% confidence intervals (CI) were employed to assess this association.

RESULTS

Ten articles were screened out, including 6177 breast cancer patients and 6726 matched-controls. For rs3918242 (-1562 C/T), 6 studies contained 1435 patients and 1446 controls. Although the frequency of risk allele C was higher in breast cancer patients than in controls, only TT genotype in recessive model was significantly associated with increased risk of breast cancer (TT vs. CT+CC: OR=1.55, 95% CI=1.12-2.16, P=0.009) in a fixed-effects model. This significant relationship was not observed in other genetic models (P>0.05). No significant association was found between breast cancer risk and rs17576, rs2250889, and rs3787268 under any genetic models.

CONCLUSIONS

Our results show that TT genotype of MMP-9-1562 C/T polymorphism might be a risk factor for breast cancer. More studies are needed to further explore this 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.

Common low-penetrance risk variants associated with breast cancer in Polish women

Background

Breast cancer is the most common type of cancer and the second leading cause of cancer-death among women in Poland. The known high-risk mutations account for 25% of familial aggregation cases and 5% of total breast cancer predisposition. Genome-wide association studies have identified a number of common low-penetrance genetic variants, but their contribution to disease risk differs between populations.

Methods

To verify selected associations with breast cancer susceptibility among Polish women, the replication study was performed, included 1424 women with breast cancer and 1788 healthy persons. Sixteen single-nucleotide polymorphisms (SNPs) were analyzed using TaqMan SNP Genotyping Assays. Allele frequency differences were tested using chi²-test implemented in PLINK v1.07 and Cochran-Armitage trend test was performed using R software.

Results

Significant differences (Bonferroni corrected p-value_cor ≤ 0.0197) in the frequency of alleles distribution between all cancer and control subjects were observed for four (rs2736098, rs13281615, rs1219648, rs2981582) out of 16 SNPs. The same result was obtained for group of patients without high-risk BRCA1/2 mutations. The rs1219648 (p-value_cor ≤ 6.73E-03) and rs2981582 (p-value_cor ≤ 6.48E-03) SNPs showed significant association with both familial and sporadic cancers. Additionally, rs2736098 (p-value_cor ≤ 0.0234) was associated with only sporadic cancers; also in group without carriers of high-risk mutation. All these associations revealed their significance also in Cochran-Armitage trend test. Opposite to other SNPs, rs2736098 was associated with a decreased risk of breast cancer.

Conclusion

The association of four known susceptibility SNPs, representing three individual loci, with breast cancer risk in Polish women was confirmed. One of them (rs2736098) seems to be specific for the Polish population. Due to the population differences in allele frequencies, identification of general genetic risk factors requires sets of association studies conducted on different populations.

Two nonsynonymous polymorphisms (F31I and V57I) of the STK15 gene and breast cancer risk: a meta-analysis based on 5966 cases and 7609 controls

OBJECTIVES

This meta-analysis examined the relationship between two nonsynonymous polymorphisms (F31I and V57I) of the aurora kinase A (STK15) gene and breast cancer risk.

METHODS

A systematic search of the PubMed® and EMBASE™ databases was undertaken to identify case-control studies that investigated the relationship between STK15 gene polymorphisms and breast cancer risk.

RESULTS

This meta-analysis included seven case-control studies (5966 breast cancer cases; 7609 controls). Combined results, based on all seven studies, showed that breast cancer cases had a significantly higher frequency of the 31 Ile/Ile genotype. In a subgroup analysis by race, breast cancer cases had a significantly higher frequency of the 31 Ile/Ile genotype in Asians and Caucasians. Combined results, based on four studies, suggested that the STK15 V57I gene polymorphism was unlikely to be associated with breast cancer risk in either Asians or Caucasians.

CONCLUSIONS

The present meta-analysis suggests that the STK15 F31I polymorphism is a strong predisposing risk factor for breast cancer, but no significant association existed between the STK15 V57I polymorphism and the risk of breast cancer.

Does mammographic density reflect the expression of breast cancer markers?

Mammographic density reflects variation in breast tissue composition as detected on mammogram. It is associated with a number of well-known breast cancer risk factors and itself is considered one of the strongest risk factors for breast cancer. If the expression of several proteins and genes within the breast tissue influences mammographic density in the same way as it influences breast cancer risk, then mammographic density might serve as an intermediate biomarker in future epidemiological studies on breast cancer. This has the potential to provide a quick means for predicting the effect of changes in the breast microenvironment on breast cancer risk without having to wait for an eventual development of breast cancer. In this review, the expression of several proteins and genes (growth factors, enzymes, proteoglycans and pro-inflammatory markers) within the breast tissue is shown to be associated with mammographic density. These proteins and genes are suspected to play a role in breast carcinogenesis. More studies assessing differential expression of proteins and genes in mammary epithelium and stroma and their association with mammographic density among premenopausal and postmenopausal women are required. Identification of proteins and genes influencing mammographic density may provide further insight on the molecular causes of breast cancer.

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.

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

PURPOSE

Matrix metalloproteinase (MMP) 1, MMP2, MMP3 and MMP9 are important members of the MMP family. Recently, many studies have been carried out on the association between polymorphisms of MMP1-1607 1G/2G, MMP2-735 C/T, MMP2-1306 C/T, MMP3-1171 5A/6A and MMP9-1562 C/T and lung cancer risk. However the results of these studies remained inconclusive due to conflicting results from different case-control studies. To clarify these associations, we conducted a meta-analysis.

METHODS

We conducted a comprehensive search in Medline, EMBASE, OVID and Chinese Biomedical Literature Database (date from Jan 2000 to Aug 2012). Overall and subgroup analysis by the ethnicity of study population was carried out. Odds ratio (OR) with 95% confidence interval (95%CI) was used to assess the strength of the association.

RESULTS

There were 17 studies involving five polymorphic sites in four MMP genes. For MMP1-1607,increased lung cancer risk was found under dominant model (MMP1-1607 1G/2G: OR=1.14, 95%CI=1.03-1.26, P=0.01), but not in the Caucasian population. For MMP2-1306 C/T, T polymorphism decreased lung cancer risk under dominant and recessive models (dominant, OR=0.63, 95%CI=0.46-0.88, P=0.0006; recessive, OR=0.61, 95%CI=0.38-0.99, P=0.04). For MMP9-1562 C/T, TT genotype decreased this risk under the recessive model (OR=0.38, 95%CI=0.19-0.75, P=0.005), but not in the Asian population. For MMP2-735 C/T and MMP3-1171 5A/6A, there was no association between this polymorphism and lung cancer risk under the dominant and recessive models.

CONCLUSIONS

MMP1-1607 1G/2G polymorphism increased lung cancer risk in Asians. It was also found that MMP2-1306 C/T polymorphism decreased lung cancer risk in Asians, while MMP9-1562 C/T polymorphism decreased lung cancer risk in Caucasians. No significant difference was found in any genotype of MMP2-735 C/T and MMP3-1171 5A/6A. Further studies with larger sample sizes should be carried out.

Plasma matrix metalloproteinases and postmenopausal breast cancer risk: a nested case-control study in the Multiethnic Cohort study

The survival of malignant breast cells depends upon the remodeling of the extracellular matrix, including complex interactions with matrix metalloproteinases (MMPs). It has been hypothesized that circulating MMPs may serve as early indicators of breast cancer development in hospital-based case-control studies. A nested case-control study of the association of pre-diagnostic plasma levels of MMPs with the subsequent risk of postmenopausal breast cancer was conducted within the Multiethnic Cohort. During the follow-up period, 713 women with incident invasive breast cancer were identified and individually (1:1) matched to controls. Four types of MMPs (1, 2, 3, and 7) were analyzed by microsphere immunofluorescence assay. Mean plasma levels of MMPs did not differ significantly between cases and controls; nor were there differences in breast cancer risk by MMP level. No difference in the risk of breast cancer by plasma level of the MMPs was found within strata of age, or ethnicity, although MMP-1 levels were positively associated with breast cancer risk in obese women and women by hormone replacement medications (P values for interaction <0.05). Few significant differences in risk by levels of the MMPs were found by any of the clinical variables. Circulating MMPs were not associated with postmenopausal breast cancer risk.

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.

MMP-1 expression has an independent prognostic value in breast cancer

Background

Breast cancer consists of a variety of tumours, which differ by their morphological features, molecular characteristics and outcome. Well-known prognostic factors, e.g. tumour grade and size, Ki-67, hormone receptor status, HER2 expression, lymph node status and patient age have been traditionally related to prognosis. Although the conventional prognostic markers are reliable in general, better markers to predict the outcome of an individual tumour are needed.

Matrix metalloproteinase-1 (MMP-1) expression has been reported to inversely correlate with survival in advanced cancers. In breast cancer MMP-1 is often upregulated, especially in basal-type breast tumours. The purpose of this retrospective study was to analyse MMP-1 expression in breast cancer cells and in cancer associated stromal cells and to correlate the results with traditional prognostic factors including p53 and bcl-2, as well as to patient survival in breast cancer subtypes.

Methods

Immunohistochemical analysis of MMP-1, ER, PR, Ki-67, HER2, bcl-2, p53 and CK5/6 expression was performed on 125 breast cancers. Statistical analyses were carried out using Kruskal-Wallis and Mann-Whitney -tests. In pairwise comparison Bonferroni-adjustment was applied. Correlations were calculated using Spearman rank-order correlation coefficients. Kaplan-Meier survival analyses were carried out to compare breast cancer-specific survival curves. Factors significantly associated with disease-specific survival in univariate models were included in multivariate stepwise.

Results

Positive correlations were found between tumour grade and MMP-1 expression in tumour cells and in stromal cells. P53 positivity significantly correlated with MMP-1 expression in tumour cells, whereas HER2 expression correlated with MMP-1 both in tumour cells and stromal cells. MMP-1 expression in stromal cells showed a significant association with luminal A and luminal B, HER2 overexpressing and triple-negative breast cancer subtypes.

Conclusions

The most important finding of this study was the independent prognostic value of MMP-1 as well as Ki-67 and bcl-2 expression in tumour cells. Our study showed also that both tumoural and stromal MMP-1 expression is associated with breast tumour progression and poor prognosis. A significant difference of MMP-1 expression by cancer associated stromal cells in luminal A, luminal B and triple-negative breast cancer classes was also demonstrated.

Please see related commentary article http://www.biomedcentral.com/1741-7015/9/95

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.