Project description:Mammary gland branching morphogenesis is thought to depend on the mobilization of the membrane-anchored matrix metalloproteinases, MT1-MMP and MT2-MMP, that drive epithelial cell invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that these proteinases play during mammary gland development in vivo remains undefined. A mammary gland branching program that occurs during the first 10 days of early postnatal development was used to characterize the impact of global Mt1-mmp or Mt2-mmp targeting on mammary gland morphogenesis. Transcriptome profiling of ductal networks and associated stroma was used to investigate the functional roles of MT1-MMP in the early postnatal mammary gland in an unbiased fashion.
Project description:Mammary gland branching morphogenesis is thought to depend on the mobilization of the membrane-anchored matrix metalloproteinases, MT1-MMP and MT2-MMP, that drive epithelial cell invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that these proteinases play during mammary gland development in vivo remains undefined. A mammary gland branching program that occurs during the first 10 days of early postnatal development was used to characterize the impact of global Mt1-mmp or Mt2-mmp targeting on mammary gland morphogenesis. Transcriptome profiling of ductal networks and associated stroma was used to investigate the functional roles of MT2-MMP in the early postnatal mammary gland in an unbiased fashion.
Project description:Expression of the MT1-MMP gene induces a significant upregulation of of oncogenes and tumorignenic genes in 184B5-MT1 cells. Keywords: Genetic modification
Project description:Mammary gland branching morphogenesis is thought to relie on the mobilization of the membrane-anchored matrix metalloproteinase, Mmp14/MT1-MMP, to drive mammary epithelial invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that this proteinase plays during postnatal mammary gland development in vivo remain undefined. A mammary gland branching program that occurs during the first 4 weeks of postnatal mouse development, in tandem with recently developed Mmp14-floxed mice and MMTV-Cre transgenics that express Cre recombinase throughout the mammary epithelial cell compartment, were used to characterize the impact of deleting epithelial cell Mmp14 on mammary gland morphogenesis. Transcriptome profiling of mammary epithelial cells was used to investigate the functional roles of MT1-MMP in the postnatal mammary epithelial cell compartment in an unbiased fashion
Project description:Integrin signaling plays a fundamental role in the establishment of focal adhesions and the subsequent formation of invadopodia in malignant cancer cells. Invadopodia facilitate localized adhesion and degradation of the extracellular matrix (ECM), which promote tumour cell invasion and metastasis. Degradation of ECM components is often driven by membrane type-1 matrix metalloproteinase (MT1-MMP), and we have recently shown that regulation of enzyme internalization is dependent on signaling downstream of β1 integrin. Phosphorylation of the cytoplasmic tail of MT1-MMP is required for its internalization and delivery to Rab5-marked early endosomes, where it is then able to be recycled to new sites of invadopodia formation and promote invasion. Here we found that inhibition of β1 integrin, using the antibody AIIB2, inhibited the internalization and recycling of MT1-MMP that is necessary to support long-term cellular invasion. MT1-MMP and β1 integrin were sequestered at the cell surface when β1-integrin was inhibited, and their association under these conditions was detected using immunoprecipitation and mass spectrometry analysis. Sequestration of β1 integrin and MT1-MMP at the cell surface resulted in the formation of large invadopodia and local ECM degradation; however, the impaired internalization and recycling of MT1-MMP and β1 integrin ultimately led to a loss of invasive behaviour.
Project description:Invasive cancers employ pericellular proteolysis to breach the extracellular matrix and basement membrane barriers and invade the surrounding tissue. Pro-invasive, pro-tumorigenic MT1-MMP is the primary mediator of proteolytic events on the cancer cell surface. Cellular MT1-MMP is synthesized as a latent zymogen. The latency of MT1-MMP is maintained by its N-terminal inhibitory prodomain. Our study reveals a critical mechanism underlying the activation pathway and subsequent execution of the tumor-promoting function of MT1-MMP. Evidence suggests that the prodomain undergoes intradomain cleavage at the PGD↓L50 cleavage site followed by the release of the degraded prodomain by furin cleavage of the R108RKR111↓Y112 site. These events, only if combined, cause the activation of MT1-MMP. The significance of these molecular events to the pro-tumorigenic function of MT1-MMP in malignancy remained, however, unidentified. To identify the functional importance of the PGD↓L50 intradomain cleavage in the activation and tumorigenic program of MT1-MMP, our current studies employed the cells which expressed the wild-type prodomain-based fluorescent biosensor and the mutant biosensor with the inactivated PGD↓L50 cleavage site (L50D mutant) and also the cells with the enforced expression the wild-type and mutant MT1-MMP. Using cell-based tests and orthotopic breast cancer xenografts in mice, we demonstrated that the intradomain cleavage of the PGD↓L50 sequence of the prodomain is essential for the pro-tumorigenic function of MT1-MMP. Our study contributes to the growing consensus for the design of selective, precisely focused MT1-MMP inhibitors in cancer. Analysis of global gene expression in orthotopic tumor and cultured breast cancer cells expressing wild-type and mutant Mt1-MMP forms
Project description:Invasive cancers employ pericellular proteolysis to breach the extracellular matrix and basement membrane barriers and invade the surrounding tissue. Pro-invasive, pro-tumorigenic MT1-MMP is the primary mediator of proteolytic events on the cancer cell surface. Cellular MT1-MMP is synthesized as a latent zymogen. The latency of MT1-MMP is maintained by its N-terminal inhibitory prodomain. Our study reveals a critical mechanism underlying the activation pathway and subsequent execution of the tumor-promoting function of MT1-MMP. Evidence suggests that the prodomain undergoes intradomain cleavage at the PGD↓L50 cleavage site followed by the release of the degraded prodomain by furin cleavage of the R108RKR111↓Y112 site. These events, only if combined, cause the activation of MT1-MMP. The significance of these molecular events to the pro-tumorigenic function of MT1-MMP in malignancy remained, however, unidentified. To identify the functional importance of the PGD↓L50 intradomain cleavage in the activation and tumorigenic program of MT1-MMP, our current studies employed the cells which expressed the wild-type prodomain-based fluorescent biosensor and the mutant biosensor with the inactivated PGD↓L50 cleavage site (L50D mutant) and also the cells with the enforced expression the wild-type and mutant MT1-MMP. Using cell-based tests and orthotopic breast cancer xenografts in mice, we demonstrated that the intradomain cleavage of the PGD↓L50 sequence of the prodomain is essential for the pro-tumorigenic function of MT1-MMP. Our study contributes to the growing consensus for the design of selective, precisely focused MT1-MMP inhibitors in cancer.
Project description:Genome-wide expression profiling of MT1-MMP–overexpressing versus MT1-MMP–silenced cancer cells and a further data mining analysis of the preexisting expression database of 190 human tumors of 14 cancer types led us to identify 11 genes, the expression of which correlated firmly and universally with that of MT1-MMP (P < 0.00001).
Project description:VSMC-specific MT1-MMP gene targeting in APOE-null mice promotes atherosclerosis and iliac artery aneurysm formation. To determine the MT1-MMP-dependent regulation of VSMC function, whole-genome transcriptomes of wild-type and MT1-MMP-null APOE-null VSMCs were determined. We used microarray-based transcriptome analysis to detect MT1-MMP-dependent regulation of VSMC function under atherogenic conditions.
Project description:In order to investigate the impact of MMP-14 (MT1-MMP) on the transcriptomes of a human breast adenocarcinoma cell line, we performed a microarray analysis from RNAs isolated from MCF-7 cells expressing either an empty vector (VEC) or human MMP-14 cDNA (MT1) in monolayer growth conditions.