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Purpose: The present study investigated the profiles of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) of the aqueous humor (AH) and plasma (PL) in myopia patients, to determine whether there was an association between these levels with their axial length (AL) and to investigate if MMPs/TIMPs were regulated locally or systemically., Methods: A cross-sectional study was conducted. Thirty-nine patients (78 eyes) diagnosed with high myopia were recruited. The AL was measured using IOL Master. And the patients were divided into three groups based on their AL, Group A (AL ≤ 26 mm), Group B (26 < AL ≤ 28 mm), and Group C (AL > 28 mm). The AH in both eyes and blood samples were collected before the patients underwent implantable collamer lens surgery. In all, 78 samples of the AH and 39 samples of the PL were analyzed using MILLIPLEX map assays, followed by statistical analyses of the results., Results: There were 8 patients (16 eyes) in Group A, 22 patients (44 eyes) in Group B, and 9 patients (18 eyes) in Group C. MMP-1 ( p = 0.014, Β = 0.118), MMP-2 ( p ≤ 0.001, Β = 0.278), MMP-9 ( p ≤ 0.001, Β = 0.019), and TIMP-1 ( p = 0.014, Β = 0.062) in the AH were positively associated with the AL. MMP-1 ( p = 0.004, Β = 0.001) and TIMP-1 ( p = 0.030, Β = 1.171) concentrations in the PL increased linearly with longer ALs. No concentration-dependent relationship was found between MMP-2 in the PL and AL., Conclusions: There was a consistent relationship between MMP-2 in the AH and AL. AL was not consistently or substantially affected by MMP-2 in the PL, indicating myopia formation was possibly a localized process. Associations among MMP-1, MMP-9, and TIMP-1 in the AH and AL were also observed., Competing Interests: The authors declare that they have no conflicts of interest. The authors have no commercial interests in the subject of the manuscript or in entities discussed in the manuscript., (Copyright © 2020 Yu Yue et al.)

The skin surface temperature reflects the physiological state of the human body. Quantitative methods of identification of skin cancers based on accurate measurement of effective thermal conductivity (ETC) are among the promising diagnostic tools for differentiating non-invasive and invasive melanomas before surgical treatment. To validate these findings, in this report, the diagnostic methods for invasive and non-invasive extramammary Paget's disease (EMPD) and squamous cell carcinoma (SCC) were further tested by measuring the absolute value of skin surface temperature and the ETC of the skin. In addition, to investigate the stromal factors that might affect ETC, immunohistochemical staining for LL37, periostin (POSTN), MMP12, and MMP28 was performed. The invasive SCC and EMPD group showed a relatively higher skin surface temperature compared to the in situ SCC group. The non-invasive EMPD and SCC group showed significantly lower values of ETC at lesions, whereas the invasive EMPD group showed significantly higher ETC values at lesions compared to healthy skin. Immunohistochemical staining showed that the percentage of LL37-producing cells was significantly increased in invasive EMPD and SCC compared to that in non-invasive EMPD and SCC. Moreover, Spearman's rank correlation test showed a significant inverse correlation between the percentage of MMP12-positive cells and increased levels of ETC-expressing areas in EMPD and SCC (r = -.5997). The present study suggested that differences in ETC could be a novel high-accuracy diagnostic technique for non-melanoma skin cancer, especially for detecting dermal invasion of SCC and EMPD., (© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: Preeclampsia is the most common disorder associated with pregnancy. Our earlier findings revealed a substantial increase in the amount of matrix metalloproteinase-26 (matrilysin 2; MMP-26) in preeclamptic umbilical cord blood. The role of MMP-26 in preeclamptic umbilical cord tissue has not been fully elucidated. Some reports have indicated that the expression of matrilysin 2 and tissue inhibitor of matrix metalloproteinase 4 (TIMP-4) is coordinately regulated during progression of various diseases., Study Design: Therefore, we decided to assess the expression and activity of MMP-26 and TIMP-4 in normal and preeclamptic umbilical cord tissues - umbilical cord arteries (UCA), vein (UCV) and Wharton's jelly (WJ). Tissues obtained from 10 normal (control material) and 10 preeclamptic umbilical cords were assessed using immunoenzymatic assay, Western immunoblotting, reverse transcriptase - polymerase chain reaction and fluorometric determination of the enzyme activity., Results: All umbilical cord tissues, both control and preeclamptic, expressed MMP-26 and TIMP-4 in macromolecular complexes. Preeclampsia induced a significant increase in the content and actual activity of MMP-26 in UCV and WJ, as compared to control. The content of TIMP-4 in preeclamptic UCV and WJ was reduced. The content of MMP-26 mRNA was lower in UCA and UCV, whereas higher in WJ in preeclampsia., Conclusions: Divergent changes in MMP-26 mRNA and protein expression suggest a difference in the factors controlling the matrilysin synthesis in healthy and preeclamptic subjects. The decrease in TIMP-4 content in preeclamptic UCV might be the main reason for significantly higher actual activity of MMP-26 in that tissue. Only in preeclamptic Wharton's jelly the changes were compatible in terms of the content and activity of MMP-26 and TIMP-4. It cannot be excluded that similar alterations can be observed for the whole vascular system of newborns delivered by mothers with preeclampsia., (Copyright © 2018. Published by Elsevier B.V.)

Degeneration of IVD is a progressive and irreversible process and can be evaluated with immunohistochemical examination or radiological grading. MMPs are a family of proteolytic enzymes and involved in the degradation of the matrix components of the IVD. We aimed to compare MMP-1, -2, -3, and -9 expressions with demographic features, visual analogue scale (VAS), Oswestry Disability Index (ODI) and radiological (MRI) grades. The study involved 60 participants. We recorded data about age, complaint, radiological imaging, expression levels of MMP-1, -2, -3, and -9, ODI and VAS for back pain retrospectively. Intervertebral disc degeneration was graded on a 0-5 scale according to the Pfirrmann classification. As a result of the study, the median age was 52.09±12.74years. There were statistical significances between age and MMP-1, and MMP-2. There was a close correlation between grade and MMP-9. We found correlation between the VAS and the MMP-9 expression. In addition, there was relationship between expression of MMP-2 and MMP-1, MMP-3, MMP-9. In conclusion, the expressions of MMP-1 and -2 are increased with aging. There was no relationship between radiological evaluation of IVDD and aging. Increased expression of MMPs affected IVDD positively. The relationship with MMPs is not explained. This study adds to our understanding of the interaction between MMPs and IVDD., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Osteoarthritis (OA) is a chronic inflammatory disease and is characterized as a degenerative process. This study aimed to evaluate and compare the effects of a topical nonsteroidal anti-inflammatory drug (NSAID), physical activity, and photobiomodulation therapy (PBMT) applied alone and/or in combination between them in an experimental model of knee OA. OA was induced by injection of papain in the knees of rats. After 21 days, the animals started to be treated with the above treatment. Histological analysis shows that the experimental model of OA induction causes morphological changes consistent with the disease, and among treatments, the PBMT is the most effective for reducing these changes. Moreover, the results demonstrate that PBMT and NSAID reduce the total number of cells in the inflammatory infiltrate (p<0.05) and PBMT was the most effective for reducing the activity of myeloperoxidase (p<0.05). Finally, we observed that both NSAID and PBMT were effective for reducing the gene expression of MMP-3 (p<0.05), but in relation to the gene expression of MMP-13, PBMT was the most effective treatment (p<0.05). The results of this study indicate that PBMT is the most effective therapy in stopping disease progression, and improving inflammatory conditions observed in OA.

Objectives: In a previous study on smelter workers we, found significant relationship between exposure to dust and accelerated annual decline in forced expiratory volume in 1 s (FEV1). In this cross-sectional study at the end of a follow-up, we aimed to investigate the possible association between annual decline in FEV1 and markers of airways, and systemic inflammation in smelter workers., Methods: Employees (n=76 (27 current smokers)) who had been part of a longitudinal study (9-13 years) that included spirometry (>6 measurements) and respiratory questionnaires, performed induced sputum, exhaled NO and had blood drawn. Participants with annual decline in FEV1≥45 mL were compared with participants with annual decline <45 mL; also 26 non-exposed controls were included., Results: Compared with non-exposed controls, smelter workers demonstrated a significantly increased percentage of neutrophils (mean (SD)) (57% (17) vs 31% (15)) and matrix metalloproteinases 8 (MMP-8) levels in sputum, and MMP-9, surfactant protein D (SpD) and transforming growth factor β (TGFb) levels in blood. A significant association in FEV1≥45 mL was found for blood neutrophils when controlling for smoking habits (OR=1.7 (95% CI 1.0 to 2.8), p=0.045). Airway and blood protein markers were not associated with annual decline in FEV1., Conclusions: All workers displayed airway and systemic inflammation characterised by increased levels of neutrophils and MMP-8 in sputum, and MMP-9, SpD and TGFβ in blood compared with non-exposed controls. Blood neutrophils in particular were significantly elevated in those workers with the most rapid decline in lung function. A similar observation was not seen with airway neutrophils. In the present study, we were able to identify systemic but not airway inflammatory markers that can predict increased decline in FEV1 in smelter workers., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

As the newest identified member of the matrix metalloproteinase (MMP) family, the expression pattern and function of epilysin (MMP-28) are still not well understood. Although epilysin was found to play an evolutionarily conserved role in neural development, the expression and function of epilysin in malignant glioma are unknown. Therefore, the aim of the present study was to quantitatively evaluate the expression level of epilysin in glioblastoma (GBM) and its association with clinical outcome of patients. For this purpose, a total of 216 GBM specimens and 31 normal brain specimens were collected in the present study. Expression level of epilysin was determined by immunohistochemistry assay and immunoreactivity score system. MGMT promoter methylation and IDH1/2 mutation status in GBM were also evaluated. Results showed that the positive rate of epilysin staining in GBM was significantly elevated compared with that in normal brain. Positive epilysin staining was associated with low KPS score, unmethylated MGMT promoter and wild-type IDH. Kaplan-Meier analysis showed that patients with GBM of positive epilysin staining were more likely to have unfavorable overall survival. Multivariate analysis revealed that epilysin was an independent and significant prognostic marker of GBM. These results proved for the first time that epilysin expression was significantly elevated in GBM and can be potentially used to predict prognosis in patients with GBM.

Human extravillous trophoblast (EVT) invades the decidua via integrin receptors and subsequently degrades extracellular matrix proteins. In preeclampsia (PE), shallow EVT invasion elicits incomplete spiral artery remodeling, causing reduced uteroplacental blood flow. Previous studies show that preeclamptic decidual cells, but not interstitial EVTs, display higher levels of extracellular matrix-degrading matrix metalloproteinase (MMP)-9, but not MMP-2. Herein, we extend our previous PE-related assessment of MMP-2 and MMP-9 to include MMP-1, which preferentially degrades fibrillar collagens, and MMP-3, which can initiate a local proteolytic cascade. In human first-trimester decidual cells incubated with estradiol, tumor necrosis factor-α (TNF-α) significantly enhanced MMP-1, MMP-3, and MMP-9 mRNA and protein levels and activity measured by real-time quantitative RT-PCR, ELISA, immunoblotting, and zymography, respectively. In contrast, interferon γ (IFN-γ) reversed these effects and medroxyprogesterone acetate elicited further reversal. Immunoblotting revealed that p38 mitogen-activated protein kinase signaling mediated TNF-α enhancement of MMP-1, MMP-3, and MMP-9, whereas IFN-γ inhibited p38 mitogen-activated protein kinase phosphorylation. Unlike highly regulated MMP-1, MMP-3, and MMP-9, MMP-2 mRNA and protein expression was constitutive in decidual cells. Because inflammation underlies PE-associated shallow EVT invasion, these results suggest that excess macrophage-derived TNF-α augments expression of MMP-1, MMP-3, and MMP-9 in decidual cells to interfere with normal stepwise EVT invasion of the decidua. In contrast, decidual natural killer cell-derived IFN-γ reverses such TNF-α-induced MMPs to protect against PE., (Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

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-21 (MMP-21) has been shown to enhance tumor invasion and metastasis ability in some solid tumors. In the present study, we investigated the expression of MMP-21 as well as its association with overall survival of gastric cancer patients. MMP-21 expression was investigated in 296 cases of gastric cancer by immunohistochemistry assay. Statistical analysis was utilized to evaluate the association of MMP-21 expression with overall survival of patients. MMP-21 expression was proved to be increased in gastric cancer compared with that in normal tissues (P < 0.05). It was also proved MMP-21 expression was associated with tumor invasion, metastasis and TNM stage (P < 0.001). MMP-21 expression was showed to be associated with overall survival of gastric cancer patients for patients with tumor of higher MMP-21 expression tend to have worse overall survival (P < 0.001). Multivariate analysis proved MMP-21 to be an independent prognostic factor for overall survival of gastric cancer patients (P < 0.001). These results suggested the potential role of MMP-21 in progression of human gastric cancer. It might also be a novel molecular marker to predict overall survival of patients with gastric cancer.

Aim: Matrix metalloproteinase (MMP)-14 and MMP-19 have been demonstrated to play an important role in the development of human gliomas. However, their prognostic values are not clear. The aim of this study was to investigate whether co-expression of MMP-14 and MMP-19 has prognostic relevance in human gliomas., Methods: Immunohistochemistry and western blot were used to investigate the expression of MMP-14 and MMP-19 proteins in 128 patients with gliomas., Results: The expression levels of MMP-14 and MMP-19 proteins in glioma tissues were both significantly higher (both P < 0.001) than those in non-neoplastic brain tissues according to the immunohistochemistry analysis, which was confirmed by the western blot analysis. Additionally, the overexpression of either MMP-14 or MMP-19 was significantly associated with the advanced WHO grade (both P = 0.02), the low Karnofsky performance score (KPS) (P = 0.008 and 0.01, respectively) and the poor overall survival (both P = 0.01). Moreover, the Multivariate Cox proportional-hazards regression analysis revealed that the increased expressions of MMP-14 and MMP-19 were both independent prognostic factors for poor overall survival (both P = 0.02). Furthermore, the co-expression of MMP-14 and MMP-19 was additively and more significantly (P = 0.006) associated with adverse prognosis in patients with gliomas than respective expression of MMP-14 and MMP-19., Conclusions: These findings indicated for the first time that the co-expression of MMP-14 and MMP-19 is significantly correlated with prognosis in glioma patients, suggesting that the co-expression of these proteins may be used as both an early diagnostic and independent prognostic marker.

Background: The current understanding of hormonal regulation of matrix metalloproteinase-26 (MMP-26) in the primate endometrium is incomplete. The goal of this work was to clarify estrogen and progesterone regulation of MMP-26 in the endometrium of ovariectomized, hormone-treated rhesus macaques., Methods: Ovariectomized rhesus macaques (n= 66) were treated with estradiol (E(2)), E(2) plus progesterone, E(2) followed by progesterone alone or no hormone. Endometrium was collected from the hormone-treated animals during the early, mid- and late proliferative and secretory phases of the artificial menstrual cycle. MMP-26 expression was quantified by real-time PCR, and MMP-26 transcript and protein were localized by in situ hybridization and immunohistochemistry and correlated with estrogen receptor 1 and progesterone receptor (PGR)., Results: MMP-26 was localized to glandular epithelium and was undetectable in the endometrial stroma and vasculature. MMP-26 transcript levels were minimal in the hormone-deprived macaques and treatment with E(2) alone did not affect MMP-26 levels. Treatment with progesterone both in the presence and absence of E(2) stimulated MMP-26 expression in the early and mid-secretory phases (P < 0.001). MMP-26 expression preceded decidualization of endometrial stroma. MMP-26 levels then declined to baseline in the late secretory phase (P < 0.01) despite continued E(2) plus progesterone treatment. Loss of detectable MMP-26 expression in the late secretory phase was correlated with late secretory phase loss of glandular epithelial PGR., Conclusions: Endometrial MMP-26 expression is dependent on the presence of progesterone in the early secretory phase and then gradually becomes refractory to progesterone stimulation in the late secretory phase. In the macaque, MMP-26 is a marker of the pre-decidual, secretory endometrium. During the second half of the late secretory phase, and during decidualization, MMP-26 loses its response to progesterone concurrent with the loss of epithelial PGR. The decline in MMP-26 levels between the mid- and late secretory phases may play a role in the receptive window for embryo implantation.

Objective: To evaluate the immunohistochemical expression of MMP-1, -2, -7, -9 and -26 in oral squamous cell carcinomas (SCCs) according to tumour site and histological grade of malignancy., Study Design: Fifteen cases of SCC of the lower lip and 15 cases of tongue SCC were selected and divided into low grade malignancy (n = 17) and high grade malignancy (n = 13)., Results: Higher immunohistochemical expression of MMPs by neoplastic cells was observed in tongue SCCs, with a statistically significant difference for MMP-9 (P < 0.05). High-grade SCCs showed a higher expression of MMPs, except for MMP-2, with a statistically significant difference for MMP-7 (P < 0.05) and MMP-26 (P < 0.05). In addition, a direct association was observed between morphological scores of malignancy and MMP immunoreactivity, with the association being significant for MMP-7 and MMP-26., Conclusion: The present results demonstrate the important role of MMPs in the development of SCCs of the lower lip and tongue., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Studies on metastasic lesions from human carcinomas are scarce. Therefore there is a need for such studies to identify the expression of the biological factors that will help in the assessment of the natural history of breast cancer. Here an immunohistochemical study was performed using tissue arrays and specific antibodies against matrix metalloproteinases (MMPs)-1, 2, 7, 9, 11, 13, 14 and tissue inhibitors of metalloproteases (TIMPs)-1, 2 and 3 in 39 patients with breast cancer. Specimens from 39 patients with node-positive carcinomas were examined and the analysis was performed at the central core of the tumour, at the invasive front, and in the metastasic axillary lymph nodes (MALNs). Global expression of MMP-1, 7 and 14, TIMP-1, and 3, were significantly higher at the centre of the tumour compared with the invasive front or the MALNs. Significantly higher expression of MMP-7 and 14, and TIMP-3, by fibroblast-like cells and mononuclear inflammatory cells (MICs) was seen in MALNs. In addition, in the tumour centre, the expression of MMP-11 and TIMP-1 and 2 by MICs, as well as TIMP-2 expression by fibroblast-like cells, were associated significantly with the occurrence of distant metastasis. In contrast, TIMP-3 expression by tumour cells or by fibroblast-like cells in this same tumour locations, as well as TIMP-1 expression by fibroblast-like cells at the invasive front, were associated significantly with poor prognosis. However, the expression of all of these biological factors in MALNs was not associated with the development of distant metastasis. Our data suggest that there is prognostic relevance to the expression of MMPs and TIMPs in the stromal cells of primary tumours, rather than to the expression of these enzymes in MALNs.

Background: Ameloblastoma is the most common clinically-significant epithelial odontogenic tumor, and is considered a benign but locally-aggressive tumor of the craniofacial region. Osteonectin/secreted protein acidic and rich in cysteine (SPARC) is induced in response to a number of biological processes such as tumor growth and metastasis, whereas matrix metalloproteinases (MMPs) degrade the extracellular matrix and participate in various biological processes including tumor invasion and metastasis. We hypothesize that SPARC acts with MMPs for the local invasiveness of ameloblastoma. The aim of this study was to examine the association of SPARC with MMP-1, MMP-2, and MMP-9 in ameloblastoma., Method: Immunohistochemical expression of SPARC, MMP-1, MMP-2, and MMP-9 as well as co-expression of SPARC and MMP-9 were examined in a cohort of 23 cases of ameloblastoma., Results: SPARC, MMP-1, -2, and -9 were detected in the cytoplasm of the ameloblastic-like columnar cells and stellate-reticulum-like cells as well as in the stromal tissues of fibroblasts and endothelial cells of our cohort of ameloblastoma patients. Furthermore, co-expression of SPARC and MMP-9 were found in 23 cases of ameloblastoma. This may be the first study to demonstrate that the expression level of SPARC was statistically correlated with MMP-9 but not with MMP-1 or -2 in ameloblastoma., Conclusion: Our results suggest a putative association between SPARC and MMPs (especially MMP-9) in ameloblastoma to regulate tumor invasion.

Objective: The aim was to evaluate the expression of matrix metalloproteinases (MMPs) 7 and 26 in ameloblastomas and adenomatoid odontogenic tumors (AOTs)., Study Design: Twenty intraosseous solid ameloblastomas and 10 intraosseous AOTs were evaluated regarding immunohistochemical expression of MMP-7 and -26 in the epithelium and stroma., Results: There was no statistically significant difference in MMP-7 and -26 expression between the epithelium of ameloblastomas (P = .50) and AOTs (P = .90). Stromal staining for MMP-7 was evident in all cases. For MMP-26, stromal staining was observed in 65% of ameloblastomas and 50% of AOTs, and this difference was not statistically significant (P = .69)., Conclusion: The marked expression of these matrilysins suggests their role in the process of tissue remodeling and growth in the studied tumors, but it does not relate to the their distinct patterns of aggressiveness.

Background and Objective: Matrix metalloproteinase (MMP)-26 has been implicated in genesis, progression, invasion and metastasis of several types of human cancers. This study was to investigate the expression of MMP-26 protein in invasive non-small cell lung cancer (NSCLC), pre-invasive lung cancer and normal lung tissues, thus to explore the role of MMP-26 in the progression and prognosis of NSCLC., Methods: SP immunohistochemistry was used to measure the expression of MMP-26 protein in 72 specimens of NSCLC, 14 specimens of atypical hyperplasia and 10 specimens of normal lung tissues., Results: The high expression rate of MMP-26 was 0 (0/10) in normal lung tissues, 14.3% (2/14) in atypical hyperplasia and 59.7% (43/72) in NSCLC. The expression rate of MMP-26 protein was significantly higher in NSCLC than in atypical hyperplasia and normal lung tissues (p < 0.01); the expression was higher in atypical hyperplasia than in normal lung tissues, but the difference was not significant (p > 0.05). The high expression rate of MMP-26 protein was significantly correlated to stage (p < 0.05) and lymph node metastasis (p < 0.05), but not to age, gender, tumor size and differentiation (p > 0.05). Multivariate analysis showed that MMP-26 and stage were independent prognostic factors of NSCLC (p < 0.05). The disease-free survival and overall survival were shorter in NSCLC patients with high expression of MMP-26 than in those with low expression of MMP-26 (log-rank = 19.34 and 23.2, both p < 0.001)., Conclusions: High expression of MMP-26 protein is correlated to carcinogenesis, lymph node metastasis, clinical stage and prognosis of NSCLC. Therefore, MMP-26 may be served as a tumor marker in monitoring progression and predicting prognosis of NSCLC.

Matrix metalloproteinases (MMPs) are zinc-dependent proteases whose physiological roles include control of leukocyte migration. They are implicated in tissue destruction in inflammatory and infectious diseases. MMPs are not only capable of degrading all components of the extracellular matrix, but they also can modulate the immune response by cleaving cytokines and chemokines to alter their activity. Macrophages secrete a broad range of MMPs and represent a key source of MMPs in inflammatory lesions such as granulomas. Zymography is substrate-based gel electrophoresis that allows direct visualization of MMP activity. Here we describe measurement of MMP secretion from macrophages focusing on quantitative zymography. We also discuss complementary methods that should be used in parallel with zymography. The ability to analyze and quantify MMP secretion by macrophages offers an additional window through which to understand the contributions of macrophages to a wide variety of infectious, inflammatory, and immunologic disorders.

Matrix metalloproteinases (MMPs) are a family of 23 extracellular proteases that are best known for their collective ability to degrade all components of the extracellular matrix. We previously demonstrated that genetic ablation of MMP-7 reduced tumour multiplicity in multiple intestinal neoplasia (Min) mice possessing a genetic alteration in the adenomatous polyposis coli gene (APC). These mice, commonly referred to as APC-Min mice, are a frequently used model of early intestinal tumourigenesis. To examine further the role of MMPs in intestinal tumour development, we generated APC-Min mice genetically deficient in MMP-2, -9, -12 or -19. Genetic ablation of MMP-2, -12 or -19 did not affect multiplicity or size of intestinal tumours when crossed into the APC-Min system. However, MMP-9 deficient animals developed 40% fewer tumours than littermate controls, although tumour size distribution remained unaffected. Intestinal adenomas from MMP-9 deficient mice demonstrated a 50% decrease in proliferating cells compared with control tissues, with no difference in apoptosis. To determine the cellular origin of MMP-9 in these tumours, immunofluorescent co-staining with markers for different leucocyte lineages was used to demonstrate that intratumoural MMP-9 is largely a product of neutrophils. These studies extend the potential targets for chemoprevention of intestinal adenomas to MMP-9 in addition to MMP-7 and exclude MMP-2,-12,-19 as attractive targets for intervention.

Background: Carotid endarterectomy to prevent a stroke is less beneficial for women compared with men. This benefit is lower in asymptomatic women compared with asymptomatic men or symptomatic patients. A possible explanation for this gender-associated difference in outcome could be found in the atherosclerotic carotid plaque phenotype. We hypothesize that women, especially asymptomatic women, have more stable plaques than men, resulting in a decreased benefit of surgical plaque removal., Methods: Carotid endarterectomy specimens of 450 consecutive patients (135 women, 315 men) were studied. The culprit lesions were semi-quantitatively analyzed for the presence of macrophages, smooth muscle cells, collagen, calcifications, and luminal thrombus. Plaques were categorized in three phenotypes according to overall presentation and the amount of fat. Protein was isolated from the plaques for determination of interleukin-6 (IL-6) and IL-8 concentrations and matrix metalloproteinase-8 (MMP-8) and MMP-9 activities., Results: Atheromatous plaques (>40% fat) were less frequently observed in women than in men (22% vs 40%; P < .001). In addition, plaques obtained from women more frequently revealed low macrophage staining (11% vs 18%; P = .05) and strong smooth muscle cell staining (38% vs 24%; P = .001). Compared with men, women had a lower plaque concentration of IL-8 (P = .001) and lower MMP-8 activity (P = .01). The observed differences were most pronounced in asymptomatic women, who showed the most stable plaques, with an atheromatous plaque in only 9% of cases compared with 39% in asymptomatic men (P = .02). In addition, a large proportion of plaques obtained from asymptomatic women showed high smooth muscle cell content (53% vs 30%; P = .03) and high collagen content (55% vs 24%; P = .003). All relations between gender and plaque characteristics, except for MMP-8, remained intact in a multivariate analysis, including clinical presentation and other cardiovascular risk factors., Conclusion: Carotid artery plaques obtained from women have a more stable, less inflammatory phenotype compared with men, independent of clinical presentation and cardiovascular risk profile. Asymptomatic women demonstrate the highest prevalence of stable plaques. These findings could explain why women benefit less from carotid endarterectomy compared with men.

Primary neuroendocrine carcinoma of the skin, or Merkel cell carcinoma, is the most aggressive cutaneous neoplasm. In spite of its similarities to small cell carcinomas from other locations, Merkel cell carcinoma shows many peculiarities probably related to its epidermal origin and the etiologic role of UV radiation. We have immunohistochemically investigated 43 markers on a tissue microarray in which 31 surgically resected Merkel cell carcinomas were represented. Of these, 15 patients remained free of disease after removal, whereas 16 developed metastases. Immunoreactivity was scored according to staining intensity and the percentage of positive cells. We found statistically significant correlations between metastatic tumor spread and overexpression of matrix metalloproteinase (MMP) 7, MMP10/2, tissue inhibitor of metalloproteinase 3, vascular endothelial growth factor (VEGF), P38, stromal NF-kappaB, and synaptophysin. Also detected were statistically significant correlations between the expression levels of MMP7 and VEGF, MMP7 and P21, MMP7 and P38, MMP10/2 and VEGF, P38 and synaptophysin, P38 and P53, and P21 and stromal NF-kappaB. These findings may be helpful in predicting the clinical course of Merkel cell carcinoma and are potentially useful for the development of targeted therapies.

The induction of the expression of matrix metalloproteinases (MMPs) and their extracellular activation are key processes in connective tissue degradation in the chorioallantoid membrane during rat labour. However, the regulatory mechanisms remain largely unknown. Here, we report the identification of a calcium-dependent high molecular weight complex composed of MMP-9, MMP-3, MMP-2, tissue inhibitor of metalloproteinase 1 (TIMP-1) and TIMP-2, identified by zymography and western blotting. Molecular sieve chromatography confirmed the presence of a complex of MMPs and TIMPs with an exclusion volume >670 kDa. Differential scanning calorimetry of the complex confirmed the existence of a macromolecular complex that unfolds with a broad transition; it is denatured over a wide range of temperatures and has a T(m) of 72 degrees C in the presence of Ca(2+). When denatured in the absence of Ca(2+), there were at least eight transitions with T(m)s that corresponded to pro-MMP-9, MMP-9, pro-MMP-3, MMP-3, pro-MMP-2, MMP-2, TIMP-1 and TIMP-2. Co-localization of the same molecular components was demonstrated by confocal microscopy using cell-depleted chorioallantoid membranes. The assembly and disassembly of the complex can be reproduced at physiological concentrations of Ca(2+). This complex provides a potential mechanism for the enzymatic regulation of MMPs, which may participate in connective tissue degradation leading to the rupture of the fetal membranes during labour.