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  • Type IV collagenase(s) and TIMPs modulate endothelial cell morphogenesis in vitro. 8344982

    It has been proposed that proteases are important in endothelial cell behavior. We examined the contribution of the gelatinase/type IV collagenase system in an in vitro model of endothelial differentiation. Human umbilical vein endothelial cells rapidly align and form networks of tubes when cultured on a basement membrane preparation, Matrigel. Zymograms of culture supernates demonstrate a 72-kD and a 92-kD gelatinase activity; the cells produce most of the 72-kD gelatinase, whereas the 92-kD activity is derived entirely from the Matrigel. Addition of antibodies against type IV gelatinase/collagenase decreases the area of the tube network. Both tissue inhibitors of metalloproteinases, TIMP-1 and TIMP-2, similarly decrease tube formation when added to cultures. Conversely, exogenous recombinant 72-kD gelatinase increases tube-forming activity. The effects of the anti-gelatinase antibodies and the TIMPs are not additive. Inhibition by either antibodies or TIMPs is greatest when they are added at culture initiation, suggesting that the protease activity is important in the early steps of morphogenesis. However, culture of the cells on Matrigel does not increase early expression of mRNA for the 72-kD gelatinase. Expression of message for the enzyme actually decreases during the course of the assay, while transcription of mRNAs for TIMPs increases, further supporting the concept that collagenases facilitate an early event in tube formation. These data demonstrate that gelatinase/type IV collagenase activity is important in endothelial cell morphogenesis on Matrigel, and suggest a role for collagenases in formation of new capillaries in vivo.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Type IV collagen stimulates pancreatic cancer cell proliferation, migration, and inhibits apoptosis through an autocrine loop 23530721

    Background: Pancreatic cancer shows a highly aggressive and infiltrative growth pattern and is characterized by an abundant tumor stroma known to interact with the cancer cells, and to influence tumor growth and drug resistance. Cancer cells actively take part in the production of extracellular matrix proteins, which then become deposited into the tumor stroma. Type IV collagen, an important component of the basement membrane, is highly expressed by pancreatic cancer cells both in vivo and in vitro. In this study, the cellular effects of type IV collagen produced by the cancer cells were characterized.
    Methods: The expression of type IV collagen and its integrin receptors were examined in vivo in human pancreatic cancer tissue. The cellular effects of type IV collagen were studied in pancreatic cancer cell lines by reducing type IV collagen expression through RNA interference and by functional receptor blocking of integrins and their binding-sites on the type IV collagen molecule.
    Results: We show that type IV collagen is expressed close to the cancer cells in vivo, forming basement membrane like structures on the cancer cell surface that colocalize with the integrin receptors. Furthermore, the interaction between type IV collagen produced by the cancer cell, and integrins on the surface of the cancer cells, are important for continuous cancer cell growth, maintenance of a migratory phenotype, and for avoiding apoptosis.
    Conclusion: We show that type IV collagen provides essential cell survival signals to the pancreatic cancer cells through an autocrine loop.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Reg IV is a direct target of intestinal transcriptional factor CDX2 in gastric cancer. 23133598

    REG4, which encodes Reg IV protein, is a member of the calcium-dependent lectin superfamily and potent activator of the epidermal growth factor receptor/Akt/activator protein-1 signaling pathway. Several human cancers overexpress Reg IV, and Reg IV expression is associated with intestinal phenotype differentiation. However, regulation of REG4 transcription remains unclear. In the present study, we investigated whether CDX2 regulates Reg IV expression in gastric cancer (GC) cells. Expression of Reg IV and CDX2 was analyzed by Western blot and quantitative reverse transcription-polymerase chain reaction in 9 GC cell lines and 2 colon cancer cell lines. The function of the 5'-flanking region of the REG4 gene was characterized by luciferase assay. In 9 GC cell lines, endogenous Reg IV and CDX2 expression were well correlated. Using an estrogen receptor-regulated form of CDX2, rapid induction of Reg IV expression was observed in HT-29 cells. Reporter gene assays revealed an important role in transcription for consensus CDX2 DNA binding elements in the 5'-flanking region of the REG4 gene. Chromatin immunoprecipitation assays showed that CDX2 binds directly to the 5'-flanking region of REG4. These results indicate that CDX2 protein directly regulates Reg IV expression.
    Document Type:
    Reference
    Product Catalog Number:
    17-371
    Product Catalog Name:
    EZ-ChIP™

  • Type IV collagen as a tumour marker for colorectal liver metastases. 21620632

    About 50% of patients with primary colorectal cancer (CRC) will develop liver metastases (CLM). Currently, carcinoembryonic antigen (CEA) is the most common tumour marker for CRC and CLM. However, the sensitivity and specificity of this marker is not optimal, as almost 50% of patients have tumours that do not produce CEA. Therefore there is a need for better markers for CRC and CLM.
    Document Type:
    Reference
    Product Catalog Number:
    MAB1910
    Product Catalog Name:
    Anti-Collagen Type IV α 2 Chain Antibody, clone 23IIC3

  • Type IV collagen is a tumour stroma-derived biomarker for pancreas cancer. 19491897

    Pancreas cancer is a dreaded disease with high mortality, despite progress in surgical and oncological treatments in recent years. The field is hampered by a lack of good prognostic and predictive tumour biomarkers to be used during follow-up of patients.The circulating level of type IV collagen was measured by ELISA in pancreas cancer patients and controls. The expression pattern of type IV collagen in normal pancreas, pancreas cancer tissue and in pancreas cancer cell lines was studied by immunofluorescence and Western blot techniques.Patients with pancreas cancer have significantly increased circulating levels of type IV collagen. In pancreas cancer tissue high levels of type IV collagen expression was found in close proximity to cancer cells in the tumour stroma. Furthermore, pancreas cancer cells were found to produce and secrete type IV collagen in vitro, which in part can explain the high type IV collagen expression observed in pancreas cancer tissue, and the increased circulating levels in pancreas cancer patients. Of clinical importance, our results show that the circulating level of type IV collagen after surgery is strongly related to prognosis in patients treated for pancreas cancer by pancreatico-duodenectomy with curative intent. Persisting high levels of circulating type IV collagen after surgery indicates a quick relapse in disease and poor survival.Our results most importantly show that stroma related substances can be evaluated as potential cancer biomarkers, and thereby underline the importance of the tumour microenvironment also in this context.
    Document Type:
    Reference
    Product Catalog Number:
    MAB1910
    Product Catalog Name:
    Anti-Collagen Type IV α 2 Chain Antibody, clone 23IIC3

  • M(r) 92,000 type IV collagenase is increased in plasma of patients with colon cancer and breast cancer. 8416738

    Overproduction of matrix metalloproteinases (MMPs) is a common characteristic of metastatic cancer cells. Since MMPs can be identified in plasma, we proposed that enhanced MMP-9 secretion by invasive cancer cells may be detected by plasma assay. To this end, we developed a specific sandwich enzyme-linked immunosorbent assay which uses two mouse monoclonal antibodies to human M(r) 92,000 type IV collagenase (MMP-9). The plasma concentration of MMP-9 (mean +/- SD) in 60 healthy subjects (9 +/- 11 ng/ml), 136 patients without cancer, and 179 patients with cancer of the lung, genitourinary tract, or lymphomas-leukemias did not differ significantly. In contrast, plasma MMP-9 was significantly increased (P < 0.01) in 122 patients with gastrointestinal tract cancer and breast cancer (18 +/- 23 and 21 +/- 22 ng/ml, respectively). Whereas carcinoembryonic antigen levels were significantly increased in patients with stage IV gastrointestinal cancer, MMP-9 concentrations were not significantly increased in patients with metastatic disease as compared to those with nonmetastatic cancer. Combining both assays improves sensitivity of detection of colon cancer. MMP-9 was also significantly increased during pregnancy which is consistent with the extensive ongoing tissue remodeling and the leaching of the tissue proteinase into plasma.
    Document Type:
    Reference
    Product Catalog Number:
    CC1048
    Product Catalog Name:
    MMP-9, human, proform

  • Interaction of 92-kDa type IV collagenase with the tissue inhibitor of metalloproteinases prevents dimerization, complex formation with interstitial collagenase, and acti ... 1311314

    Secreted metalloproteases initiating proteolytic degradation of collagens and proteoglycans play a critical role in remodeling of the connective tissue. Activation of the secreted proenzymes and interaction with their specific inhibitors TIMP and TIMP-2 are responsible for regulation of enzyme activity in extracellular space. We have previously demonstrated that 92- and 72-kDa Type IV procollagenases, in contrast to interstitial collagenase (ClI), form specific complexes with TIMP and the related inhibitor TIMP-2, respectively. The physiologic significance of the proenzyme-inhibitor complex and the mechanism of activation of Type IV collagenases remained unclear. Here, we demonstrate that in the absence of TIMP, 92-kDa Type IV procollagenase (92T4Cl) can form a covalent homodimer and a novel complex with ClI. In the presence of TIMP, the formation of a 92T4Cl proenzyme complex with TIMP prevents dimerization, formation of the complex with ClI, and activation of the 92T4Cl proenzyme by stromelysin, a related metalloprotease. The proenzyme homodimer is unable to form a complex with TIMP. All TIMP-free forms of the proenzyme can be activated by stromelysin. The 92T4Cl-ClI complex can be activated to yield a complex active against both gelatin and fibrillar Type I collagen, suggesting a mechanism for cooperative action of two enzymes in reducing collagen fibrils to small peptides under physiologic conditions.
    Document Type:
    Reference
    Product Catalog Number:
    CC1048
    Product Catalog Name:
    MMP-9, human, proform

  • 72 KD and 92 KD type IV collagenase, type IV collagen, and laminin mRNAs in breast cancer: a study by in situ hybridization. 8014478

    It is widely accepted that basement membrane (BM) components are synthesized by epithelial cells and that production of BM-degrading proteases by cancer cells is necessary for invasive growth. In this study we used nucleic acid in situ hybridization (ISH) to investigate the presence of mRNAs for 72 KD and 92 KD Type IV collagenase, alpha 1 (IV) chain of Type IV collagen, and laminin B1 chain in 20 breast carcinomas of various histological types. The mRNA signals for 72 KD Type IV collagenase, Type IV collagen, and laminin were much more abundant in stromal fibroblasts and endothelial cells than in carcinoma cells. The signal for 92 KD Type IV collagenase mRNA was strong in carcinoma cells and considerably weaker in stromal fibroblasts and endothelial cells. Labeling for 72 KD and 92 KD Type IV collagenase mRNA was also found in benign fibroadenomas and for 92 KD Type IV collagenase in non-neoplastic ducts and acini. The results indicate that stromal cells have a more important role in the synthesis and degradation of BMs in breast carcinomas than previously thought and that production of these enzymes is not restricted to malignancy.
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple

  • Astragaloside IV prevents MPP⁺-induced SH-SY5Y cell death via the inhibition of Bax-mediated pathways and ROS production. 22278385

    Parkinson's disease (PD) is characterized by a progressive degeneration of dopaminergic neurons in the substantia nigra. Oxidative stress and neural degeneration are suggested to be involved in the pathogenesis of PD. Previous studies have revealed that Astragaloside IV (AS-IV) can reduce inflammation and oxidation, making it a potential therapeutic agent for neurodegenerative disease. In this study, we investigated whether AS-IV protect against 1-methyl-4-phenylpyridnium ion (MPP(+))-induced dopaminergic neurotoxicity in SH-SY5Y cells and determined the mechanism of AS-IV neuroprotection. We found that pretreatment with AS-IV significantly reversed the loss of cell viability, nuclear condensation, the generation of intracellular reactive oxygen species (ROS), and the increase in Bax/Bcl-2 ratio and the activity of caspase-3 induced by MPP(+). Our study suggests that the neuroprotective effect of AS-IV is related to mechanisms including ROS production and the inhibition of Bax-mediated pathway. The present study supports the notion that AS-IV may be a promising neuroprotective agent for the treatment of neurodegenerative disorders such as PD.
    Document Type:
    Reference
    Product Catalog Number:
    AB3623
    Product Catalog Name:
    Anti-Caspase 3 Antibody, active (cleaved) form

  • The angiotensin IV analog Nle-Tyr-Leu-psi-(CH2-NH2)3-4-His-Pro-Phe (norleual) can act as a hepatocyte growth factor/c-Met inhibitor. 20086056

    The angiotensin (Ang) IV analog norleual [Nle-Tyr-Leu-psi-(CH2-NH2)(3-4)-His-Pro-Phe] exhibits structural homology with the hinge (linker) region of hepatocyte growth factor (HGF) and is hypothesized to act as a hinge region mimic. Norleual competitively inhibited the binding of HGF to its receptor c-Met in mouse liver membranes, with an IC(50) value of 3 pM. Predictably, norleual was able to inhibit HGF-dependent signaling, proliferation, migration, and invasion in multiple cell types at concentrations in the picomolar range. Ex vivo studies demonstrated that norleual exhibited potent antiangiogenic activity, an attribute that would be predicted for a HGF/c-Met antagonist. Furthermore, norleual suppressed pulmonary colonization by B16-F10 murine melanoma cells, which are characterized by an overactive HGF/c-Met system. Together, these data suggest that AngIV analogs exert at least some of their biological activity through interference with the HGF/c-Met system and may have utility as therapeutic agents in disorders that are dependent on an intact HGF/c-Met system. Finally, the ability of norleual to induce marked biological responses in human embryonic kidney cells, which do not express insulin-responsive aminopeptidase (IRAP), coupled with the observed effects of norleual on the HGF/c-Met system, casts doubt on the physiological significance of AngIV-dependent inhibition of IRAP. [Corrected]
    Document Type:
    Reference
    Product Catalog Number:
    Multiple
    Product Catalog Name:
    Multiple