Résumé
OBJECTIVE@#To explore the effect of all-trans-retinoic acid (ATRA) on the growth inhibition and cellular differentiation of C6 glioma cells.@*METHODS@#Human glioma C6 cells were treated with 5 mg/L ATRA,and the inhibition of cell growth was assessed by methyl thiazolyl tetrazolium assay. The differentiation of C6 cells was determined by flow cytometry, microscopy,transmission electron microscope, and immunohistochemical technique.@*RESULTS@#Treatment of ATRA could result in the growth inhibition of C6 cells, and the cell density significantly decreased(P0.05).Whereas, early apoptosis was observed under the transmission electron microscope, the vacuoles increased, the mitochondria and endoplasmic reticulum were abundant in the cytoplasm, and the cellular structures tended to be normal.The expression of glial fibrillaryacidic protein in C6 cells increased in the treatment group.@*CONCLUSION@#ATRA can inhibit the proliferation, and induce the differentiation of C6 glioma cells.
Sujets)
Animaux , Humains , Souris , Antinéoplasiques , Pharmacologie , Tumeurs du cerveau , Anatomopathologie , Prolifération cellulaire , Transformation cellulaire néoplasique , Gliome , Anatomopathologie , Trétinoïne , Pharmacologie , Cellules cancéreuses en cultureRésumé
OBJECTIVE@#To examine the expression absence of LRRC4 gene in glioblastoma cell lines.@*METHODS@#RT-PCR and Northern blot were used to detect the expression of LRRC4 gene in 6 glioblastomas cells lines. Polymerase chain reaction and DNA sequencing were used to screen the LRRC4 gene mutation, while bioinformation assay was used to search for the reason of LRRC4 gene absence in U251 cell lines.@*RESULTS@#The expression of LRRC4 was absent in 6 malignant glioma cell lines (U251, U87, BT325, SF126, SF767 and M17), which were examined by Northern-blot and RT-PCR assay. All sequencing of PCR products from gDNA of SF126, SF767, and M17 cell lines contained the point mutation at the same position ( LRRC4 geneT977A) (3/5), which was a synonymous mutation. However, PCR products from gDNA of U251 and U87 cell lines (2/5) were not obtained. The expression absence of LRRC4 was ascribed to the loss of homozygosity of 7q32-ter in U251 cell lines.@*CONCLUSION@#The expression of LRRC4 gene is absent in glioblastoma cell lines, and it offers the important experiment proof for LRRC4 to act as a new candidate of brain tumor suppressor gene from glioma. The loss of homozygosity of 7q32-ter contributed to the expression absence of LRRC4 in U251 cell lines.
Sujets)
Humains , Séquence nucléotidique , Technique de Northern , Tumeurs du cerveau , Génétique , Anatomopathologie , Lignée cellulaire tumorale , Analyse de mutations d'ADN , Régulation de l'expression des gènes tumoraux , Glioblastome , Génétique , Anatomopathologie , Protéines de tissu nerveux , Génétique , Mutation ponctuelle , RT-PCRRésumé
OBJECTIVE@#To explore the effect of LRRC4 on the mobility and invasion of glioblastomas U251 cells through the SDF-1alpha/CXCR4 axis.@*METHODS@#RT-PCR, transfilter cell invasion assay, adhesion assay, scraping test, scrape loading, and dye transfer assay were used to determine the effect of LRRC4 on U251 cells.@*RESULTS@#SDF-1 alpha could increase the invasion in U251 which expressed CXCR4. The reintroduction of LRRC4 in U251 cells could inhibit the expression of CXCR4. LRRC4 also inhibited the adhesion ability of U251 to ECV304 as well as the mobility and invasion ability in vitro, which was mediated by the SDF-1alpha/CXCR4 axis. Furthermore, LRRC4 could greatly enhance the gap junctional intercellular communication of U251 cells.@*CONCLUSION@#The reintroduction of LRRC4 in U251 cells can inhibit the expression of CXCR4 and the SDF-1alpha/CXCR4 axis-mediated cell invasion in vitro.
Sujets)
Humains , Adhérence cellulaire , Lignée cellulaire tumorale , Mouvement cellulaire , Chimiokine CXCL12 , Métabolisme , Glioblastome , Anatomopathologie , Invasion tumorale , Protéines de tissu nerveux , Génétique , Récepteurs CXCR4 , MétabolismeRésumé
The genetic analysis of herpesviruses has been a constant challenge, due to the large, complex genomes of herpesviruses and mutagenesis of viral genes by conventional recombination methods in cell culture. Recently, a completely new approach for full-length infectious clones of herpesviruses based on bacterial artificial chromosomes (BACs) has been developed. This technique allows the maintenance, propagation and genetic modification of the viral genome as a BAC plasmid in E.coli, thus making the procedures fast, safe and effective in prokaryotic cells. This technique also makes it possible for the reconstitution of viral progeny or mutants by transfection of the BAC plasmid into eukaryotic cells, thereby facilitating the analysis of viral gene functions in the context of genome. In this presentation, Epstein-Barr virus was used as an example to describe the principle, establishment of the technique and mutation introduction into the BAC plasmid, and to discuss the perspective in the use of BAC-cloned herpesviruses.