Project description:Despite the growing recognition of the role of the stroma in cancer growth, invasive behavior and metastasis, the exact mechanisms of its participation remain unclear. We have explored the relationships between the epithelial/mesenchymal (E/M) state of colorectal cancer cells, their ability to activate fibroblasts, and the expression of collagen related genes. To this end, we studied (i) co-cultures of colorectal cancer cells with different hybrid E/M states and normal fibroblasts in a collagen matrix and (ii) patient-derived cancer-associated fibroblasts (CAFs). Using RNA-sequencing, we found that the different cancer cells can activate normal fibroblasts, which could form dense collagen networks. The functional enrichment analysis of differentially expressed genes indicates more mesenchymal phenotype and greater motility of SW480 cells compared to HT29 cells. The genes related to collagen biosynthesis and catabolism tend to be more active in SW480 cells rather than HT29 cells. Moreover, LOXL2 and LOXL3 genes, which are necessary for collagen fibril organization, are SW480 specific, which may indicate greater input of this cell line in collagen remodeling compared to HT29 cells. The expression of several CAF marker genes is activated in NFs upon co-cultivation with HT29 and SW480. Interestingly, a more-epithelial cell line HT29 activates the fibroblasts to a greater extent, than does SW480. The co-cultivation of colon cancer cell lines HT29 or SW480 with NFs leads to the activation of collagen biosynthesis and collagen fibril organization genes in NFs. Our findings suggest that the normal fibroblasts, activated by cancer cells, contribute to the organization of the extracellular matrix. Therefore, targeting the ability of cancer cells to activate normal fibroblasts can be considered as a new therapeutic strategy.
Project description:We have sequenced miRNA libraries from human embryonic, neural and foetal mesenchymal stem cells. We report that the majority of miRNA genes encode mature isomers that vary in size by one or more bases at the 3’ and/or 5’ end of the miRNA. Northern blotting for individual miRNAs showed that the proportions of isomiRs expressed by a single miRNA gene often differ between cell and tissue types. IsomiRs were readily co-immunoprecipitated with Argonaute proteins in vivo and were active in luciferase assays, indicating that they are functional. Bioinformatics analysis predicts substantial differences in targeting between miRNAs with minor 5’ differences and in support of this we report that a 5’ isomiR-9-1 gained the ability to inhibit the expression of DNMT3B and NCAM2 but lost the ability to inhibit CDH1 in vitro. This result was confirmed by the use of isomiR-specific sponges. Our analysis of the miRGator database indicates that a small percentage of human miRNA genes express isomiRs as the dominant transcript in certain cell types and analysis of miRBase shows that 5’ isomiRs have replaced canonical miRNAs many times during evolution. This strongly indicates that isomiRs are of functional importance and have contributed to the evolution of miRNA genes
Project description:Homo sapiens fresh whole blood was infected with Candida parapsilosis. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Homo sapiens gene expression.
Project description:Homo sapiens fresh whole blood was infected with Candida glabrata. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Candida glabrata gene expression.
Project description:Homo sapiens fresh whole blood was infected with Candida tropicalis. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Measurement of Candida tropicalis gene expression.
Project description:Homo sapiens fresh whole blood was infected with Candida albicans SC5314. RNA-pool of both species extracted at 0min (control), 15, 30, 60, 120, 240 min. Samples are rRNA depleted. Expression measurement of Homo sapiens genes.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.