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Описана актуальность проблемы управления качеством поверхностного слоя при резании с опережающим пластическим деформированием. Представлены результаты исследований шероховатости поверхности при обработке резанием нержавеющих сталей с опережающим пластичес

MicroRNAs (miRNAs) as modulators of gene expression have been described to display both tumor-promoting and tumor-suppressive functions. Although their role has been studied in different tumor types, little is known about how they regulate nuclear factor κB (NF-κB) signaling in breast cancer. Here, we performed an unbiased whole genome miRNA (miRome) screen to identify novel modulators of NF-κB pathway in breast cancer. The screen identified 13 miRNA families whose members induced consistent effects on NF-κB activity. Among those, the miR-520/373 family inhibited NF-κB signaling through direct targeting of RELA and thus strongly reduced expression and secretion of the pro-inflammatory cytokines interleukin (IL)-6 and IL-8. With a combination of in vitro and in vivo approaches, we propose a metastasis-suppressive role of miR-520/373 family. miR-520c and miR-373 abrogated both in vitro cell invasion and in vivo intravasation of highly invasive MDA-MB-231 cells. However, knockdown of RELA did not affect their metastatic ability. mRNA profiling of MDA-MB-231 cells on overexpression of miR-520/373 members revealed a strong downregulation of transforming growth factor-β (TGF-β) signaling. Mechanistically, the metastasis-suppressive role of miR-520/373 can be attributed to direct suppression of TGFBR2, as the silencing of TGFBR2 phenocopied the effects of miR-520/373 overexpression on suppression of Smad-dependent expression of the metastasis-promoting genes parathyroid hormone-related protein, plasminogen activator inhibitor-1 and angiopoietin-like 4 as well as tumor cell invasion, in vitro and in vivo. A negative correlation between miR-520c and TGFBR2 expression was observed in estrogen receptor negative (ER(-)) breast cancer patients but not in the ER positive (ER(+)) subtype. Remarkably, decreased expression of miR-520c correlated with lymph node metastasis specifically in ER(-) tumors. Taken together, our findings reveal that miR-520/373 family has a tumor-suppressive role in ER(-) breast cancer by acting as a link between the NF-κB and TGF-β pathways and may thus contribute to the interplay of tumor progression, metastasis and inflammation.

Hepatitis C virus core protein forms the viral capsid and is targeted to lipid droplets (LDs) by its domain 2 (D2). By using a comparative analysis of two hepatitis C virus genomes (JFH1 and Jc1) differing in their level of virus production in cultured human hepatoma cells, we demonstrate that the core of the genotype 2a isolate J6 that is present in Jc1 mediates efficient assembly and release of infectious virions. Mapping studies identified a single amino acid residue in D2 as a major determinant for enhanced assembly and release of infectious Jc1 particles. Confocal microscopy analyses demonstrate that core protein in JFH1-replicating cells co-localizes perfectly with LDs and induces their accumulation in the perinuclear area, whereas no such accumulation of LDs and only a partial co-localization of core and LDs were found with the Jc1 genome. By using a fluorescence recovery after photobleaching assay, we found that green fluorescent protein-tagged D2 variants are mobile on LDs and that J6- and JFH1-D2 differ in their mobility. Taken together, our results demonstrate that the binding strength of the D2 domain of core for LDs is crucial for determining the efficiency of virus assembly.Hepatitis C virus core protein forms the viral capsid and is targeted to lipid droplets (LDs) by its domain 2 (D2). By using a comparative analysis of two hepatitis C virus genomes (JFH1 and Jc1) differing in their level of virus production in cultured human hepatoma cells, we demonstrate that the core of the genotype 2a isolate J6 that is present in Jc1 mediates efficient assembly and release of infectious virions. Mapping studies identified a single amino acid residue in D2 as a major determinant for enhanced assembly and release of infectious Jc1 particles. Confocal microscopy analyses demonstrate that core protein in JFH1-replicating cells co-localizes perfectly with LDs and induces their accumulation in the perinuclear area, whereas no such accumulation of LDs and only a partial co-localization of core and LDs were found with the Jc1 genome. By using a fluorescence recovery after photobleaching assay, we found that green fluorescent protein-tagged D2 variants are mobile on LDs and that J6- and JFH1-D2 differ in their mobility. Taken together, our results demonstrate that the binding strength of the D2 domain of core for LDs is crucial for determining the efficiency of virus assembly.

Chronic liver disease caused by infection with hepatitis C virus (HCV) is an important global health problem that currently affects 170 million people. A major impediment in HCV research and drug development has been the lack of culture systems supporting virus production. This obstacle was recently overcome by using JFH1-based full-length genomes that allow production of viruses infectious both in vitro and in vivo . Although this improvement was important, because of the restriction to the JFH1 isolate and a single chimera consisting of J6CF and JFH1-derived sequences, broadly based comparative studies between different HCV strains were not possible. Therefore, in this study we created a series of further chimeric genomes allowing production of infectious genotype (GT) 1a, 1b, 2a, and 3a particles. With the exception of the GT3a/JFH1 chimera, efficient virus production was obtained when the genome fragments were fused via a site located right after the first transmembrane domain of NS2. The most efficient construct is a GT2a/2a chimera consisting of J6CF- and JFH1-derived sequences connected via this junction. This hybrid, designated Jc1, yielded infectious titers 100– to 1,000-fold higher than the parental isolate and all other chimeras, suggesting that determinants within the structural proteins govern kinetic and efficiency of virus assembly and release. Finally, we describe an E1-specific antiserum capable of neutralizing infectivity of all HCV chimeras.

Colorectal cancer is the second most common cancer and the second leading cause of cancer related death in men and women in Germany according to the Robert Koch Institute. The leading cause for cancer related mortality is the development of metastasis. In our study, we aim to identify novel regulators of the metastatic process in colorectal cancer. To this end we employed next generation whole genome sequencing of resected tissues from patients with metastatic colorectal cancer. In particular, we sequenced samples from primary tumor, corresponding normal colon mucosa, metastasis and normal tissue from the metastatic site. The DNA from one patient was thereby sequenced on two different platforms, one being Illumina HiSeq the other Complete Genomics (CG). Additionally, we sequenced the transcriptome of this patient to correlate mRNA expression with genetic aberrations. This abstract focusses on the first results regarding metastatic aberrations. The average read coverage for the samples sequenced with the Illumina platform was between 50-60x and for the samples sequenced with CG between 105-135x. In total 3607 SNVs were identified in coding regions in the metastasis with both platforms, 40 of these were in exonic regions and classified as high confidence with both platforms. We also sequenced samples from an additional two patients on one sequencing platform each. One of the patients also presented with liver metastasis, the other one with a lung metastasis. These data were also compared to the data from the first patient to identify possible common aberrations as well as possible differences between the different metastatic sites. We identified several copy number changes occurring in the same chromosomal regions in different patients. Similarly, several genes affected by SNVs were common in two of the patients, while only high confidence APC mutations were common to all three patients. Seven additional genes were affected by high confidence SNVs in the two patients sequenced using the CG platform and three on the Illumina platform, two of which have not yet been characterized in the context of cancer or metastasis. Citation Format: Christine Hauser, Anna Shavinskaya, Barbara Hutter, Mohammed Abba, Olga Tkachenko, Peter Lichter, Roland Eils, Benedikt Brors, Heike Allgayer. Whole genome profiling to identify novel metastasis regulators in colorectal cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2010. doi:10.1158/1538-7445.AM2013-2010