79 research outputs found

    Bad Tumors Made Worse: SPINK1

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    Structure and computation-guided yeast surface display for the evolution of TIMP-based matrix metalloproteinase inhibitors

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    The study of protein-protein interactions (PPIs) and the engineering of protein-based inhibitors often employ two distinct strategies. One approach leverages the power of combinatorial libraries, displaying large ensembles of mutant proteins, for example, on the yeast cell surface, to select binders. Another approach harnesses computational modeling, sifting through an astronomically large number of protein sequences and attempting to predict the impact of mutations on PPI binding energy. Individually, each approach has inherent limitations, but when combined, they generate superior outcomes across diverse protein engineering endeavors. This synergistic integration of approaches aids in identifying novel binders and inhibitors, fine-tuning specificity and affinity for known binding partners, and detailed mapping of binding epitopes. It can also provide insight into the specificity profiles of varied PPIs. Here, we outline strategies for directing the evolution of tissue inhibitors of metalloproteinases (TIMPs), which act as natural inhibitors of matrix metalloproteinases (MMPs). We highlight examples wherein design of combinatorial TIMP libraries using structural and computational insights and screening these libraries of variants using yeast surface display (YSD), has successfully optimized for MMP binding and selectivity, and conferred insight into the PPIs involved

    Design of Mixing Station for Alternative Gaseous Fuels

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    Úkolem diplomové práce je navrhnout potrubní rozvod plynů do směšovací stanice a následně i navrhnout samotnou směšovací stanici. V textové části je nejprve vytvořena rešerše týkající se využívání technických a topných plynů v praxi. Na tuto část postupně navazují specifikace plynů, které se budou dopravovat do směšovací stanice. Ve výpočtové části se práce prostřednictvím výpočtových vztahů zabývá složením směsného plynu, fyzikálními vlastnostmi jednotlivých plynů i samotného plynu směsného, přičemž jsou vypočteny a navrženy potrubní tratě jednotlivých plynů směřujících do směšovací stanice. Konstrukční část práce se zabývá návrhem směšovací stanice a směšovací komory, ve které se jednotlivé plyny mísí. Grafická část práce obsahuje schémata jednotlivých potrubních tratí a směšovací stanice, 3D model směšovací komory a výkres směšovací komory.The task of the diploma thesis is to design the pipeline distribution of gases to the mixing station and then design the mixing station itself. In the text part is first created a search regarding the use of technical and heating gases in practice. This part is followed by the gas specifications that will be transported to the mixing station. In the computational part, the work with the help of calculation relations deals with the composition of the mixed gas, the physical properties of the individual gases and the mixing gas itself, and the pipelines of the individual gases leading to the mixing station are calculated and designed. The construction part deals with the design of the mixing station and the mixing chamber, in which the individual gases are mixed. The graphical part of the thesis contains diagrams of individual pipeline lines and mixing stations, a 3D model of the mixing chamber and a drawing of the mixing chamber.361 - Katedra energetikyvýborn

    Novel Pathogenic PRSS1 Variant p.Glu190Lys in a Case of Chronic Pancreatitis

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    Mutations in the PRSS1 (serine protease 1) gene encoding human cationic trypsinogen cause hereditary pancreatitis or may be associated with sporadic chronic pancreatitis. The mutations exert their pathogenic effect either by increasing intra-pancreatic trypsinogen activation (trypsin pathway) or by causing proenzyme misfolding and endoplasmic reticulum stress (misfolding pathway). Here we report a novel heterozygous c.568G>A (p.Glu190Lys) variant identified in a case with chronic pancreatitis. The parents of the index patient had no history of pancreatitis but were unavailable for genetic testing. Functional characterization revealed 2.5-fold increased autoactivation of the mutant trypsinogen relative to wild type. Unlike many other clinically relevant PRSS1 mutations, p.Glu190Lys did not alter the chymotrypsin C (CTRC)-dependent degradation of trypsinogen nor did it increase CTRC-mediated processing of the trypsinogen activation peptide. Cellular secretion of the mutant protein was unchanged indicating normal folding behavior. Based on the genetic and functional evidence, we classify the p.Glu190Lys PRSS1 variant as likely pathogenic, which stimulates autoactivation of cationic trypsinogen independently of CTRC

    Matrix Metalloproteinase-Induced Epithelial-Mesenchymal Transition in Breast Cancer

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    Matrix metalloproteinases (MMPs) degrade and modify the extracellular matrix (ECM) as well as cell-ECM and cell-cell contacts, facilitating detachment of epithelial cells from the surrounding tissue. MMPs play key functions in embryonic development and mammary gland branching morphogenesis, but they are also upregulated in breast cancer, where they stimulate tumorigenesis, cancer cell invasion and metastasis. MMPs have been investigated as potential targets for cancer therapy, but clinical trials using broad-spectrum MMP inhibitors yielded disappointing results, due in part to lack of specificity toward individual MMPs and specific stages of tumor development. Epithelial-mesenchymal transition (EMT) is a developmental process in which epithelial cells take on the characteristics of invasive mesenchymal cells, and activation of EMT has been implicated in tumor progression. Recent findings have implicated MMPs as promoters and mediators of developmental and pathogenic EMT processes in the breast. In this review, we will summarize recent studies showing how MMPs activate EMT in mammary gland development and in breast cancer, and how MMPs mediate breast cancer cell motility, invasion, and EMT-driven breast cancer progression. We also suggest approaches to inhibit these MMP-mediated malignant processes for therapeutic benefit

    Matrix Metalloproteinase-10 Is Required for Lung Cancer Stem Cell Maintenance, Tumor Initiation and Metastatic Potential

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    Matrix metalloproteinases (Mmps) stimulate tumor invasion and metastasis by degrading the extracellular matrix. Here we reveal an unexpected role for Mmp10 (stromelysin 2) in the maintenance and tumorigenicity of mouse lung cancer stem-like cells (CSC). Mmp10 is highly expressed in oncosphere cultures enriched in CSCs and RNAi-mediated knockdown of Mmp10 leads to a loss of stem cell marker gene expression and inhibition of oncosphere growth, clonal expansion, and transformed growth in vitro. Interestingly, clonal expansion of Mmp10 deficient oncospheres can be restored by addition of exogenous Mmp10 protein to the culture medium, demonstrating a direct role for Mmp10 in the proliferation of these cells. Oncospheres exhibit enhanced tumor-initiating and metastatic activity when injected orthotopically into syngeneic mice, whereas Mmp10-deficient cultures show a severe defect in tumor initiation. Conversely, oncospheres implanted into syngeneic non-transgenic or Mmp10−/− mice show no significant difference in tumor initiation, growth or metastasis, demonstrating the importance of Mmp10 produced by cancer cells rather than the tumor microenvironment in lung tumor initiation and maintenance. Analysis of gene expression data from human cancers reveals a strong positive correlation between tumor Mmp10 expression and metastatic behavior in many human tumor types. Thus, Mmp10 is required for maintenance of a highly tumorigenic, cancer-initiating, metastatic stem-like cell population in lung cancer. Our data demonstrate for the first time that Mmp10 is a critical lung cancer stem cell gene and novel therapeutic target for lung cancer stem cells
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