Involvement of microRNAs-MMPs-E-cadherin in the migration and invasion of gastric cancer cells infected with Helicobacter pylori.

It has been found that Helicobacter pylori （H. pylori）is not only the main cause of gastric cancer, but also closely related to its metastasis. E-cadherin cleavage induced by matrix metalloproteinases (MMPs) plays an important role in the tumor metastasis. In the present study, we investigated the role of microRNAs-MMPs-E-cadherin in migration and invasion of gastric cancer cells treated with H. pylori. The results showed that H. pylori induced migration and invasion of SGC-7901 cells with a down-regulation of E-cadherin expression, which were abolished by MMPs knock down, E-cadherin overexpression, mimics of miR128 and miR148a. MiR128/miR148a inhibitors restored MMP-3/MMP-7 expression, down-regulated E-cadherin level, and accelerated cellular migration and invasion. This study suggests that H. pylori induces migration and invasion of gastric cancer cells through reduction of E-cadherin function by activation of MMP-3, - 7. The present results also suggest that the activated MMPs/E-cadherin pathway is related with down-regulation of miR128/miR148a in the human gastric cancer cells infected with H. pylori.

Matrix Metalloproteinase-28 Is a Key Contributor to Emphysema Pathogenesis.

Chronic obstructive pulmonary disease (COPD) comprises chronic bronchitis and emphysema, and is a leading cause of morbidity and mortality. Because tissue destruction is the prominent characteristic of emphysema, extracellular proteinases, particularly those with elastolytic ability, are often considered to be key drivers in this disease. Several human and mouse studies have implicated roles for matrix metalloproteinases (MMPs), particularly macrophage-derived proteinases, in COPD pathogenesis. MMP-28 is expressed by the pulmonary epithelium and macrophage, and we have found that it regulates macrophage recruitment and polarization. We hypothesized that MMP-28 has contributory roles in emphysema via alteration of macrophage numbers and activation. Because of the established association of emphysema pathogenesis to macrophage influx, we evaluated the inflammatory changes and lung histology of Mmp28-/- mice exposed to 3 and 6 months of cigarette smoke. At earlier time points, we found altered macrophage polarization in the smoke-exposed Mmp28-/- lung consistent with other published findings that MMP-28 regulates macrophage activation. At both 3 and 6 months, Mmp28-/- mice had blunted inflammatory responses more closely resembling nonsmoked mice, with a reduction in neutrophil recruitment and CXCL1 chemokine expression. By 6 months, Mmp28-/- mice were protected from emphysema. These results highlight a previously unrecognized role for MMP-28 in promoting chronic lung inflammation and tissue remodeling induced by cigarette smoke and highlight another potential target to modulate COPD.

Regulation of chondrosarcoma invasion by MMP26.

The molecular mechanism underlying metastasis of chondrosarcoma (CS) remains unclarified. Here, we show that matrix metalloproteinase-26 (MMP26) level is significantly higher in the resected CS than in the adjacent healthy chondral tissue from the patients. To examine the role of MMP26 in CS invasion, we used a human CS line SW1353 and we either overexpressed or inhibited MMP26 in these cells. We found that overexpression of MMP26 in SW1353 cells increased cell invasiveness, while inhibition of MMP26 decreased cell invasiveness. To define the signal transduction cascades downstream of MMP26 activation, we applied specific inhibitors for PI3K, ERK/MAPK, JNK, and Wnt signaling, respectively, to the MMP26-overexpressing SW1353 cells. We found that only inhibition of Wnt signaling by either metformin or IWP-2 significantly decreased the effect of MMP26 on cancer cell invasion, possibly through increasing ß-catenin phosphorylation. Further, a strong correlation was detected between MMP26 levels and the ratio of phosphorylated/total ß-catenin in CS from the patients. Taken together, our study highlights MMP26-regulated Wnt signaling as a novel therapeutic target for CS.

Matrilysin-2 expression in colorectal cancer is associated with overall survival of patients.

Tumor recurrence and metastasis are pressing issues of patients with colorectal cancer who receive surgery. Matrilysin-2 (MMP-26) has been proved to play an important role during invasion and metastasis of some human solid tumor. We aimed to investigate the clinical significance and prognostic value of matrilysin-2 in human colorectal cancer. Colorectal cancer and adjacent normal samples from 201 patients were collected. Matrilysin-2 expression level was investigated by immunohistochemistry assay, and its association with overall survival of patients was analyzed by statistical analysis. Results showed that matrilysin-2 expression level significantly elevated in colorectal cancer compared with adjacent normal specimens. Matrilysin-2 expression was also found to be associated with cancer invasion, lymph node metastasis, distant metastasis, and TNM stage. In addition, survival analysis showed that elevated matrilysin-2 expression was associated with poor overall survival of patients. Cox's proportional hazards model indicated that matrilysin-2 was an independent prognostic marker for patients with colorectal cancer. The present study found that the expression of matrilysin-2 increased in colorectal cancer and was associated with tumor progression. It also provided the first evidence that matrilysin-2 expression was an independent prognostic factor for patients with colorectal cancer, which might be a high specific biomarker for colorectal cancer.

Matrix metalloproteinase-28 deletion exacerbates cardiac dysfunction and rupture after myocardial infarction in mice by inhibiting M2 macrophage activation.

RATIONALE: Matrix metalloproteinase (MMP)-28 regulates the inflammatory and extracellular matrix responses in cardiac aging, but the roles of MMP-28 after myocardial infarction (MI) have not been explored. OBJECTIVE: To determine the impact of MMP-28 deletion on post-MI remodeling of the left ventricle (LV). METHODS AND RESULTS: Adult C57BL/6J wild-type (n=76) and MMP null (MMP-28((-/-)), n=86) mice of both sexes were subjected to permanent coronary artery ligation to create MI. MMP-28 expression decreased post-MI, and its cell source shifted from myocytes to macrophages. MMP-28 deletion increased day 7 mortality because of increased cardiac rupture post-MI. MMP-28(-/-) mice exhibited larger LV volumes, worse LV dysfunction, a worse LV remodeling index, and increased lung edema. Plasma MMP-9 levels were unchanged in the MMP-28((-/-)) mice but increased in wild-type mice at day 7 post-MI. The mRNA levels of inflammatory and extracellular matrix proteins were attenuated in the infarct regions of MMP-28(-/-) mice, indicating reduced inflammatory and extracellular matrix responses. M2 macrophage activation was impaired when MMP-28 was absent. MMP-28 deletion also led to decreased collagen deposition and fewer myofibroblasts. Collagen cross-linking was impaired as a result of decreased expression and activation of lysyl oxidase in the infarcts of MMP-28(-/-) mice. The LV tensile strength at day 3 post-MI, however, was similar between the 2 genotypes. CONCLUSIONS: MMP-28 deletion aggravated MI-induced LV dysfunction and rupture as a result of defective inflammatory response and scar formation by suppressing M2 macrophage activation.

Epilysin (matrix metalloproteinase-28) contributes to airway epithelial cell survival.

MMP28 is constitutively expressed by epithelial cells in many tissues, including the respiratory epithelium in the lung and keratinocytes in the skin. This constitutive expression suggests that MMP28 may serve a role in epithelial cell homeostasis. In an effort to determine its function in epithelial cell biology, we generated cell lines expressing wild-type or catalytically-inactive mutant MMP28 in two pulmonary epithelial cell lines, A549 and BEAS-2B. We observed that over-expression of MMP28 provided protection against apoptosis induced by either serum-deprivation or treatment with a protein kinase inhibitor, staurosporine. Furthermore, we observed increased caspase-3/7 activity in influenza-infected lungs from Mmp28-/- mice compared to wild-type mice, and this activity localized to the airway epithelium but was not associated with a change in viral load. Thus, we have identified a novel role of MMP28 in promoting epithelial cell survival in the lung.

Molecular characterization of porcine MMP19 and MMP23B genes and its association with immune traits.

MMP19 and MMP23B belong to the Matrix metalloproteases (MMPs) family, which are zinc-binding endopeptidases that are capable of degrading various components of the extracellular matrix. They are thought to play important roles in embryonic development, reproduction and tissue remodeling, as well as in cell proliferation, differentiation, migration, angiogenesis, apoptosis and host defense. However, they are poorly understood in pigs. Here, we obtained the full length coding region sequence and genomic sequence of the porcine MMP19 and MMP23B genes and analyzed their genomic structures. The deduced amino acid sequence shares similar precursor protein domains with human and mouse MMP19 and MMP23B protein, respectively. Using IMpRH panel, MMP19 was mapped to SSC5p12-q11 (closely linked to microsatellite DK) and MMP23B was mapped to SSC8q11-q12 (linked to microsatellite Sw2521). Quantitative real-time PCR showed that MMP19 was abundantly expressed in the liver, while MMP23B was strongly expressed in the ovarian and heart. Furthermore, both genes were all expressed increasingly in prenatal skeletal muscle during development. Three SNPs were detected by sequencing and PCR-RFLP methods, and association analysis indicated that C203T at exon 5 of MMP19 has a significant association with the blood parameters WBC (G/L) and IgG2 (mg/mL) (P<0.05), SNP C131T at exon 3 of MMP23B is significantly associated with the blood parameters HGB (g/L) and MCH (P<0.05), and A150G in exon 4 has no significant association with the economic traits in pigs.

Non-small cell lung cancer invasion and metastasis promoted by MMP-26.

Matrix metalloproteinase 26 (MMP-26) is a novel member of the matrix metalloproteinase (MMP) family and is widely expressed in cancer cells of epithelial origin. MMP-26 has been shown to contribute to tumor development and to the restoration of tissue injury. In this study, in order to identify the functions of MMP-26 that contribute to the biological phenotype and behavior of human lung carcinoma A549 cells, we established an MMP-26 low-expressing tumor cell model using RNA interference (RNAi) transfection. These cells were used to investigate the role of MMP-26 in tumor progression. The MTT, colony forming, adhere-nce and spreading, wound-healing and Transwell chamber invasion assays were performed to analyze the invasion ability of pshRNA-MMP26-transfected A549 cells. Semi-quantitative reverse transcription polymerase chain reaction, Western blotting and double immunofluorescent staining were employed to detect the relationship between MMP-26 and MMP-9. Results showed that the adhesive rate was down-regulated in pshRNA-MMP26-transfected cells, compared to the controls. Silencing of the MMP-26 gene significantly retarded the invasiveness of A549 cells in Transwell insert invasion assays. The cells proliferated in the three-dimensional (3D) culture system. A549 cells transfected with the pshRNA-MMP26-C plasmid mainly developed reticular structures in morphology, and formed few clones with clear and smooth edges as well as tight intercellular junctions. The mRNA and protein expression of MMP-9 in pshRNA-MMP26-transfected cells were significantly lower than those of the controls. Double immunofluorescence labeling and focal laser scanning microscopy showed that MMP-26 was colocalized with MMP-9 in the controls. In conclusion, we successfully established an MMP-26 low-expressing cell model and confirmed that MMP-26 contributed to A549 cell invasion and migration in vitro. We also demonstrated that MMP-26 plays an important role in local invasion at least in part through coordination with MMP-9.

Catalytic activity of Matrix metalloproteinase-19 is essential for tumor suppressor and anti-angiogenic activities in nasopharyngeal carcinoma.

The association of Matrix metalloproteinase-19 (MMP19) in the development of nasopharyngeal carcinoma (NPC) was identified from differential gene profiling, which showed MMP19 was one of the candidate genes down-regulated in the NPC cell lines. In this study, quantitative RT-PCR and Western blot analysis showed MMP19 was down-regulated in all seven NPC cell lines. By tissue microarray immunohistochemical staining, MMP19 appears down-regulated in 69.7% of primary NPC specimens. Allelic deletion and promoter hypermethylation contribute to MMP19 down-regulation. We also clearly demonstrate that the catalytic activity of MMP19 plays an important role in antitumor and antiangiogenesis activities in comparative studies of the wild-type and the catalytically inactive mutant MMP19. In the in vivo tumorigenicity assay, only the wild-type (WT), but not mutant, MMP19 transfectants suppress tumor formation in nude mice. In the in vitro colony formation assay, WT MMP19 dramatically reduces colony-forming ability of NPC cell lines, when compared to the inactive mutant. In the tube formation assay of human umbilical vein endothelial cells and human microvascular endothelial cells (HMEC-1), secreted WT MMP19, but not mutant MMP19, induces reduction of tube-forming ability in endothelial cells with decreased vascular endothelial growth factor (VEGF) in conditioned media detected by enzyme-linked immunosorbent assay (ELISA). The anti-angiogenic activity of WT MMP19 is correlated with suppression of tumor formation. These results now clearly show that catalytic activity of MMP19 is essential for its tumor suppressive and anti-angiogenic functions in NPC.

Epilysin (MMP-28) restrains early macrophage recruitment in Pseudomonas aeruginosa pneumonia.

Several members of the matrix metalloproteinase (MMP) family function in various processes of innate immunity, particularly in controlling leukocyte influx. Epilysin (MMP-28) is expressed in numerous tissues and, in adult mice, it has the highest expression in lung, where it is detected in bronchial epithelial cells (Clara cells). Epilysin is also expressed by bone marrow-derived macrophages, but not by alveolar macrophages, suggesting that its expression by macrophages is dependent on localization and differentiation. To assess the role of this MMP, we generated epilysin-null (Mmp28(-/-)) mice. Although epilysin is constitutively expressed in normal tissues, Mmp28(-/-) mice have no overt phenotype. However, using a murine model of Pseudomonas aeruginosa pneumonia, we found that Mmp28(-/-) mice had an early increase in macrophage recruitment into the lungs, as well as enhanced bacterial clearance and reduced pulmonary neutrophilia, which we predicted were due to accelerated macrophage influx. Macrophage depletion in WT and Mmp28(-/-) mice confirmed a role for macrophages in clearing P. aeruginosa and regulating neutrophil recruitment. Furthermore, we observed that macrophages derived from Mmp28(-/-) mice migrated faster than did wild-type cells to bronchoalveolar lavage fluid from P. aeruginosa-treated mice of either genotype. These observations indicate that epilysin functions as an intrinsic negative regulator of macrophage recruitment by retarding the chemotaxis of these cells.

Nitric oxide involvement in TNF-alpha and IL-1 beta-mediated changes in human mesangial cell MMP-9 and TIMP-1.

BACKGROUND: Mesangial cells are known to secrete metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) that are capable of disrupting the glomerular basement membrane (GBM). Disruption of the GBM appears to be an important mechanism in the renal disease process, however little is known about the mechanisms involved. Therefore we examined the potential role of nitric oxide (NO) in the regulation of MMP-9 and TIMP-1 by tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) using the human mesangial cell line (HMCL). METHODS: The HMCL was treated with various concentrations of cytokines and NO inhibitors. Activity of MMP-9 was examined by gelatin zymography and TIMP-1 expression was analysed by Western blotting. NO production was measured using the Greiss assay. RESULTS: In this study, stimulation of HMCL cells with TNF-alpha or IL-1 beta, alone or in combination, led to a substantial increase in NO production, which was shown to result from an increase in the expression of the inducible form of NOS (iNOS). Treatment of cells with the specific iNOS inhibitor L-NIL potentiated the increase in MMP-9 production induced by TNF-alpha, but prevented the suppression of TIMP-1 production observed following cytokine treatment. The NO donor, sodium nitroprusside, also stimulated a substantial increase in NO production in HMCL cells, which was associated with a reduction in basal and TNF-alpha-stimulated MMP-9 and a potentiation of the cytokine-induced decrease in TIMP-1. CONCLUSIONS: Our study provides convincing evidence of a modulatory role for NO on cytokine-induced MMP-9 and TIMP-1 production in human mesangial cells.

Epilysin (MMP-28)--structure, expression and potential functions.

Epilysin (MMP-28) is the newest member of the matrix metalloproteinase (MMP) family of extracellular proteases. Together the MMPs can degrade almost all components of the extracellular matrix (ECM). MMPs also regulate cell behaviour by releasing growth factors and biologically active peptides from the ECM by modulating cell surface receptors and adhesion molecules and by regulating the activity of mediators of the inflammatory pathways. Epilysin differs from most other MMPs as it is expressed in a number of normal tissues, suggestive of functions in tissue homeostasis. The epilysin homologue in Xenopus laevis (XMMP-28) is expressed in neural tissues, where it cleaves the neural cell adhesion molecule. Enhanced expression of epilysin has been observed in basal keratinocytes during wound healing and in different forms of cancer. There are, however, also reports on the downregulation of epilysin in malignant cells. The roles of epilysin in cancer seem to vary based on tumor type and stage of the disease. Importantly, epilysin can induce stable epithelial to mesenchymal transition (EMT) when overexpressed in epithelial lung carcinoma cells. Transforming growth factor beta (TGF-beta) is a crucial mediator of this process, which was characterized by the loss of E-cadherin and increased cell migration and invasion. Current results suggest a plausible interaction between epilysin and TGF-beta also under physiological circumstances, where epilysin activity may not induce EMT but, instead, trigger less permanent changes in TGF-beta signalling and cell motility.

MMP19 is essential for T cell development and T cell-mediated cutaneous immune responses.

Matrix metalloproteinase-19 (MMP19) affects cell proliferation, adhesion, and migration in vitro but its physiological role in vivo is poorly understood. To determine the function of MMP19, we generated mice deficient for MMP19 by disrupting the catalytic domain of mmp19 gene. Although MMP19-deficient mice do not show overt developmental and morphological abnormalities they display a distinct physiological phenotype. In a model of contact hypersensitivity (CHS) MMP19-deficient mice showed impaired T cell-mediated immune reaction that was characterized by limited influx of inflammatory cells, low proliferation of keratinocytes, and reduced number of activated CD8(+) T cells in draining lymph nodes. In the inflamed tissue, the low number of CD8(+) T cells in MMP19-deficient mice correlated with low amounts of proinflammatory cytokines, especially lymphotactin and interferon-inducible T cell alpha chemoattractant (I-TAC). Further analyses showed that T cell populations in the blood of immature, unsensitized mice were diminished and that this alteration originated from an altered maturation of thymocytes. In the thymus, thymocytes exhibited low proliferation rates and the number of CD4(+)CD8(+) double-positive cells was remarkably augmented. Based on the phenotype of MMP19-deficient mice we propose that MMP19 is an important factor in cutaneous immune responses and influences the development of T cells.