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Aims: Xenograft models, namely heterotransplantation of human cancer cells or tumor biopsies into immunodeficient rodents are the major preclinical approach for the development of novel cancer therapeutics. However, in these models the animals must be used only after the severe systemic immune suppression in order to ensure graft survival. Thus, additional new human brain tumor models without immune suppression of the recipient rodent may be required. Place and Duration of Study: Laboratory of Immunochemistry, V.P. Serbsky National Research Centre for Social and Forensic Psychiatry and Department of Nanobiotechnology, N.I. Pirogov Russian State Medical University and Department of Biosynthesis of Nucleic Acids, Institute of Molecular Biology and Genetics between June 2009 and July 2010. Methodology: Brain tumor modeling was performed by intracerebral stereotactic implantation of cells to the healthy adult rats without any artificial immunodepression. Cells were implanted to the striatum region of ketamine-anesthetized rats at specific coordinates according to Swanson's rat brain atlas. Tumor growth was monitored weekly via registration of neurological signs and in vivo Bruker MRI system. Results: On the 21st day after implantation of C6 glioma, U251 or 293_CHI3L1 cells severe neurological deficit appeared in rats. Huge intracerebral tumors were found in each animal under investigation while no tumor growth was observed for at least 8 weeks in rats injected with empty vector-transfected 293 cells. Tumors contained the dense superficial cell layer and prominent lobules with central newly ingrowing blood vessels. Histological assay revealed displacement of median cerebral structures and hydrocephalus in contralateral hemisphere. All tumors were surrounded by numerous GFAP-positive reactive astrocytes. Conclusion: Positive results with transplantation of 293_CHI3L1 cells into adult rat brains without any immunosupression show the validity of this animal model. In all experiments such implantations provoked malignant tumor formation while there were no visible tumors in control rats. We believe this to be the first animal model of human brain tumor that displays the possibility to study various biologic features of and host therapeutic response to brain tumor in an immunocompetent host.
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Objective In order to provide experimental model for the research of Human hepatocellular carcinoma(HCC), characterize two newly human hepatocellular carcinoma cell lines established from fresh tumor tissues of two patients with HCC infected HBV.Methods The two cell lines were analyzed by morphology, double time, isoenzyme pedigree(LDH), AFP、HBsAg detection, karyotype analysis, heterotransplantation utilizing hematoxylin and eosin、ELISA、flow cytometry、Southern blot and so on. Results The two cell lines have been in continuous culture over 50 passages, which showed typical epithelial-like cells in morphology; the doubling time of cell population were found to be 19.5~59.2 hours,which showed aneuploidy and revealed chromosome average number ranging from 50 to 105. Hepatitis-B-virus(HBV)DNA was integrated in the genomes of XMS-1.No lines produced alpha-fetoprotein(AFP) and HBsAg at the protein level.Their LDH isenozyme spectrum were similar to those of embryonic liver and clinical hepatoma with the increase of the percentage of LDH-1(H-type); Cell cycle analysis showed that the ratio of cells in S、G2-M phase increased for the both cell lines compared with healthy human peripheral blood lymphocyte; LXY-1 produced solid tumors after subcutaneous heterotransplantation into nude mice and the tumor formation ratio of heterotransplantation were 100%.Conclusions The two cell lines maintained the biologic characteristics as human hepatocellular carcinoma, and will serve as a model for further studies of HCC.
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AIM To invesigate the effect of subarachnoid transplantation of APA microcapsulized bovine chromaffin cells (BCCs) on mRNA expression for Nav1.8 in the dorsal root ganglia neurons(DRG) of rats with neuropathic pain by means of in situ hybridization. METHODS SD rats were randomly divided into four groups of five. Normal rats were used as control group (group C). Rats with right sciatic nerve been ligated were used as CCI group. Five to six hundred empty APA microcapsules(group APA) or 5?10 6 APA microcapsulized BCCs (group APA-BCCs) were grated into subarachnoid space of CCI rats 7 days after operation. Allodynia and hyperalgesia were measured by Von-Frey filaments and CO 2 laser 7 days after transplantation. DRG in lumbar four and five was taken out and 15 ?m freezing sections were made 7 days after tansplantation. Sections was used to detect mRNA expression for TTX-resistent Na + Nav1.8 by in situ hybridization with Dig-labeled RNA probe. RESULTS The mRNA hybridization signal for Nav1.8 in DRG of group CCI and group APA was lower than that of group C. The expression of mRNA for Nav1.8 in DRG was higher in group APA-BCCs than that in group CCI and group APA with abatement of allodynia and hyperalgesia. There was no difference in the mRNA hybridization signal for Nav1.8 in DRG between group APA-BCCs and group C. CONCLUSION mRNA expression for Nav1.8 in DRG of CCI ratswas down-regulated. APA microcapsulized BCCs grafting can reverse the down-regulation of mRNA expression for Nav1.8 in DRG of CCI rats. Restoration of mRNA expression for Nav1.8 in DRG contributes to the analgesic effect of subarachnoid transplantation of APA microcapsulized BCCs.