Screening alternative splicing on long noncoding RNAs regulated by PTB in glioma / 基础医学与临床

Objective To further investigate the role of PTB in regulating the alternative splicing of lncRNAs in a glioblastoma tumorigenesis,and analyze spliced lncRNAs. Methods Analyzing array data and screening a specific set of alternative spliced lncRNAs. Total RNA was isolated from PTB knockdown glioblastoma cells (U87MG) or glioblastoma and normal cell lines and tissue samples,and subjected to real-time PCR(RT-PCR) assays to detect the expression level of spliced transcripts. Alternatively spliced lncRNAs were identified as target genes that may be regulated by PTB protein by knocking down method. Nuclear and cytoplasmic isolation were performed on T98G cells to identify cellular location of lncRNA. Results Our results uncovered PTB which impact on the transcript level of several lncRNAs including linc00882. Interestingly,the lncRNA linc00882 significantly exhibited differential spli-cing patterns between two splice variants in the PTB-abundant glioblastoma cells. The alternative splicing transcripts were located in cell cytoplasm. Conclusions The results suggest that PTB may have an effect on the alternative spli-cing of linc00882 in glioma.

Role of Dlx1 natural antisense transcript in mice brain development / 中国医学科学院学报

<p><b>OBJECTIVE</b>To explore the role of Dlx1as, a natural antisense transcript, in mice brain development.</p><p><b>METHODS</b>Based on the bioinformatic and molecular biological findings, we confirmed whether the Dlx1as has a poly-A tail. The temporal expressions of Dlx1as and Dlx1 mRNA were determined by quantitative real-time PCR and the spatial expressions of Dlx1as and Dlx1 mRNA were compared by using in situ hybridization.</p><p><b>RESULTS</b>Dlx1as had a poly-A signal. Dlx1as's expression was at a high level through a period of time in the embryo development, which was similar with Dlx1 mRNA in temporal but different in spatial.</p><p><b>CONCLUSIONS</b>Dlx1as is highly expressed in a certain period during mice brain development, which spatially supplements the mRNA expression of D1x1. Therefore, it is supposed that Dlx1as influences the mice brain development by regulating Dlx1 mRNA.</p>

Mechanism of arsenic trioxide-induced apoptosis in hepatic blastoma cells HepG2 / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of arsenic trioxide (As(2)O(3)) induced apoptosis in hepatic blastoma cells HepG2 and its effects on cell nuclear matrix related protein promyelocytic leukaemia (PML).</p><p><b>METHODS</b>HepG2 cells were cultured in MEM medium and treated with different concentrations of As(2)O(3) for either 24 h or 96 h. In situ terminal deoxynucleotidyl transferase (TdT) labeling (TUNEL) and DNA ladder were applied to detect apoptosis. Confocal microscopy and western blot were performed to observe the expression of PML.</p><p><b>RESULTS</b>TUNEL positive apoptotic cells and DNA ladder could be detected in As(2)O(3) treated groups. The expression of PML decreased in HepG2 cells with 2 micro mol/L As(2)O(3), and micropunctates characteristic of PML protein in HepG2 cell nuclei almost disappeared after the treatment of 5 micro mol/L As(2)O(3).</p><p><b>CONCLUSION</b>As(2)O(3) induces HepG2 tumor cell apoptosis in a time- and concentration-dependent manner. As(2)O(3) may degradate the PML protein in HepG2 cell nuclei. The decreased expression of PML is closely correlated with apoptosis. Nuclear matrix associated protein PML could be the target of As(2)O(3) therapy.</p>