Expression Patterns Of MMP-9 Research Articles

Immunoxpression of MMPs -9, -13 and TIMP-3 after Using Etch-and-rinse Adhesive

The aim of the present study was to determine the expression of MMP-9, MMP-13 and TIMP-3 after using the XP Bond ™ (Dentsply) dentin-bonding agent on 21 human teeth. Class I deep cavities were prepared and restored. After 01, 07, 14, 21, 30, 90 and 120 days, the teeth were extracted and processed for an immunohistochemical assessment (n=3). Immunohistochemical staining was performed using the monoclonal antibody anti-MMP-9, and polyclonal antibodies anti-MMP-13 and anti-TIMP-3. The immunoreactivity of metalloproteinases 9 and 13 was considered intense and moderate in the first storage intervals, before decreasing over time. In contrast, the immunoreactivity of TIMP-3 was considered absent in dentin and weak in pulp in the first time intervals, and completely absent in the subsequent intervals. MMP-9 expression in dentin and in pulp was prevalent in the dentinal tubules and odontoblastic layer, respectively. MMP-13 expression in dentin and in pulp was predominant in the pre-dentine region and odontoblastic layer, respectively. TIMP-3 expression was absent in dentin and predominantly located in the odontoblastic layer for pulp. In conclusion, the expression patterns of MMP-9, MMP-13 and TIMP-3 altered in the different time intervals studied. The increased expression of TIMP-3 in the first time intervals could suggest a synchronous response to the increased expression of MMPs in the same periods. The results confirmed the low performance of TIMP-3 in the physiological processes of the pulp-dentin complex for the conditions and materials tested herein.

Temporospatial expression of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in mouse antigen-induced arthritis

Several lines of evidence speak for an important role of matrix metalloproteinases (MMPs) in the development of progressive joint destruction. To better understand the role of MMPs and their tissue inhibitors (TIMPs) in this process, we have used the antigen-induced arthritis model to study the temporospatial expression of several MMPs and TIMPs during the progression of arthritis. Arthritis was induced by a single intra-articular injection of methylated bovine serum albumin (mBSA) into one or both knee joints of adult mice previously immunised against mBSA. Samples were collected at 3, 7, 21 and 42 days after induction of arthritis for histology and RNA extraction, and analysed by Northern hybridisation, histochemistry and immunohistochemistry for production of several MMPs and TIMPs -1, -2 and -3. A systematic analysis of MMP and TIMP mRNA levels in mouse knee joints demonstrated a general upregulation of both MMPs and TIMPs during progression of arthritis. Upregulation of MMP-9, -13 and -14 coincided with the advancement of cartilage degeneration, but the expression patterns of MMP-9 and -13 also followed the course of synovial inflammation. TIMPs were steadily upregulated throughout the examination period. Immunohistochemical localisation of MMPs and TIMPs suggested the synovium to be the major source of MMP and TIMP production in arthritis, although articular cartilage chondrocytes also showed an increased production of both MMPs and TIMPs.

Short-term glucocorticoid treatment of piglets causes changes in growth plate morphology and angiogenesis

Objective: Glucocorticoid treatment of children often leads to growth retardation, and the precise target(s) in the growth plate responsible for this effect are unknown. Angiogenesis is an important part of the endochondral ossification process, and VEGF expressed in the growth plate is essential for proper angiogenesis to occur. Since glucocorticoid treatment down-regulates VEGF expression in cultured chondrocytes, we hypothesized that in vivo glucocorticoid treatment could result in VEGF down-regulation in the growth plate and disturbed angiogenesis, thus contributing to the growth retardation. Design: We treated 6-week-old prepubertal piglets (10 kg) for 5 days with prednisolone (50 mg/day). Tibial growth plate sections were studied for apoptosis and the expression of VEGF protein and mRNA and MMP-9 protein. Capillaries in the metaphysis were visualized by CD31 immunostaining. Growth plate morphology (width of various zones) was determined by interactive measurements on hematoxylin/eosin stained sections and apoptotic cells were detected by TUNEL assay. Results: In the prednisolone-treated animals, the total width of the growth plate decreased to 81% of controls ( P<0.02), which was explained by a decrease of the width of the proliferative zone to 73% ( P<0.05). The treatment had no effect on the orderly organization of the chondrocyte columns. In the growth plates of control animals, apoptosis was shown in 5.8% of the hypertrophic chondrocytes and was limited to the terminal hypertrophic chondrocytes. In prednisolone-treated animals, 40.5% of the hypertrophic chondrocytes was apoptotic ( P<0.02), with apoptotic chondrocytes also appearing higher in the hypertrophic zone. We observed fewer capillaries and loss of their parallel organization in the metaphysis in the prednisolone-treated animals. The capillaries were shorter and chaotic in appearance. In contrast to controls, in prednisolone-treated animals VEGF mRNA and protein could not be detected in the hypertrophic zone of the growth plate. Trabecular bone length in the primary spongiosa was also diminished by the treatment. No changes were observed in the expression pattern of MMP-9, a matrix metalloproteinase, which is also important for angiogenesis and bone formation. Conclusions: These results indicate that short-term glucocorticoid treatment of growing piglets severely disturbs the width of the growth plate, apoptosis of chondrocytes, VEGF expression by hypertrophic chondrocytes, the normal invasion of blood vessels from the metaphysis to the growth plate and bone formation at the chondro-osseous junction. These effects could alter the dynamics of endochondral ossification and thus contribute to glucocorticoid-induced growth retardation.

Imbalance between Matrix Metalloproteinase 9 and Tissue Inhibitor of Metalloproteinases 1 Expression by Tumor Cells Implicated in Liver Metastasis from Colorectal Carcinoma.

We have evaluated the degree of MMP-9 and TIMP-1 messenger RNA (mRNA) expressions according to cell types in tumor tissues, and evaluated the implication of balance between the MMP-9 mRNA and the TIMP-1 mRNA expression in liver metastasis using orthotopic-implanted colon cancer in nude mouse, and also in 47 patients with colorectal cancer. The grade of MMP-9 or TIMP-1 mRNA expression was classified into 4 categories according to positive cell ratio. A higher grade of MMP-9 mRNA expression in tumor cells was correlated with liver metastasis in the experimental colon cancer, but was not statistically correlated in the clinical colorectal cancer. In contrast, the expression of TIMP-1 mRNA in the stromal cells of human colorectal cancer was correlated with liver metastasis. In both experimental and clinical colorectal cancer, a balance between the expression of MMP-9 mRNA and that of TIMP-1 mRNA was correlated with the occurrence of liver metastasis. The imbalance of MMP-9 dominance in tumor cells was implicated in liver metastasis. However, there was no significant relationship between the incidence of liver metastasis and the expression patterns of MMP-9 and TIMP-1 mRNA in the stromal cells. These results suggest that the balance between the expressions of MMP-9 and TIMP-1 in the tumor cells is more closely related to tumor biological behavior rather than the balance in the stromal cells.

Expression of MMP-2 and MMP-9, their inhibitors, and the activator MT1-MMP in primary breast carcinomas.

Enhanced expression of the type IV collagenases MMP-2 and MMP-9, or lack of their inhibitors TIMP-1 and TIMP-2, has been associated with tumour invasion and metastatic potential in several experimental models. Regulation of enzyme activity is clearly a key step in tumour invasion, and recently a potent activator of MMP-2, the membrane-associated MT1-MMP, has been described and characterized. Using an immunohistochemical approach, this study has examined the expression and distribution of the type IV collagenases, their inhibitors, and the activator MT1-MMP, in a series of 79 infiltrating ductal carcinomas (IDCs), 8 tubular carcinomas, and 27 infiltrating lobular carcinomas (ILCs). MMP-2 and MT1-MMP were expressed in more than 90 per cent of all carcinomas, with predominantly stromal and tumour cell cytoplasmic staining. However, reactivity localized on tumour cell membranes was recorded for MMP-2 in 34 per cent of cases with a monoclonal antibody and 55 per cent of cases with a polyclonal antibody, and for MT1-MMP in 68 per cent of tumours. In each case, this pattern of staining was significantly associated with the presence of lymph node metastasis (p=0.001, p=0. 008, and p=0.1, respectively). Both tumour cell and stromal staining was observed for TIMP-2, but there was no correlation with metastatic status. The 92 kD gelatinase MMP-9 was expressed by 68 per cent of carcinomas, either in the stromal compartment or by tumour cells. There was a highly significant correlation between the expression pattern of MMP-9 and tumour type, with ILCs displaying greater frequency and more homogeneous cytoplasmic staining than IDCs (p=0.0004). Staining for TIMP-1 was seen in the stroma and also in relation to small blood vessels, with more than 90 per cent of tumours showing this staining pattern using a polyclonal antibody. This study indicates distinct patterns of expression for different MMPs and demonstrates the potential importance of the MMP-2/MT1-MMP system in breast tumour progression. The association of MMP-9 with the infiltrating lobular phenotype may reveal novel mechanisms of control for this metalloproteinase.