Twist regulates proliferation, migration and invasion of osteosarcoma cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of Twist in regulating the proliferation, migration, and invasion of osteosarcoma cells with different levels of malignancy.</p><p><b>METHODS</b>The baseline expressions of Twist in 3 different osteosarcoma cell lines (143B, MG63 and TE85) were detected using real-time PCR and Western blotting. The cells were infected with the recombinant adenoviruses Ad-Twist or Ad-siTwist for Twist overexpression or knockdown, respectively, and the cell growth curves were drawn to assess the cell proliferation. The migration abilities and invasiveness of the cells were evaluated using wound healing assay and Transwell assay. Luc-labeled 143B cells infected with Ad-Twist or Ad-siTwist were intrathecally injected to establish nude mouse models bearing osteosarcoma xenografts, in which the tumor formation was monitored using living body imaging technique.</p><p><b>RESULTS</b>The baseline expressions of Twist in the 3 osteosarcoma cells were significantly higher than that in C3H10 cells (P<0.05). Twist expression was the highest in 143B cells followed by MG63 cells, and was the lowest in TE85 cells, indicating its positive correlation with the level of malignancy of the osteosarcoma cells. Ad-Twist or Ad-siTwist infection efficiently enhanced or lowered Twist expressions at both mRNA and protein levels in osteosarcoma cells (P<0.05). Twist overexpression resulted in enhanced proliferation, migration and invasion abilities of osteosarcoma cells, and Twist knockdown obviously inhibited the cell proliferation, migration and invasion. In nude mice, 143B cells with Twist overexpression showed accelerated tumor formation compared with the control cells, while Twist knockdown significantly inhibited the tumor formation ability of the cells.</p><p><b>CONCLUSION</b>Twist overexpression can promote the proliferation, migration, invasion and tumorigenicity of osteosarcoma cells.</p>

Studies on wnt5a inducing differentiation of cardiac progenitor cells to myocardial cells / 解放军医学杂志

Objective To investigate the effect of Wnt5a on inducing differentiation of Cp15-5a cell to myocardial cell.Methods Recombinant adenovirus wnt5a (Ad-wnt5a) and Ad-GFP was amplified with human embryo kidney 293 cells (HEK293 cells),and then transfected into CP15-5a cells and 3 experiment groups were set up:wnt5a group,GFP group and blank control group.Flow cytometry was used to detect the transfection efficiency of Ad-wnt5a and Ad-GFP.One week after transfection,the expressions of genes GATA binding protein 4 (GATA4) and myocardial enhancement factor 2C (MEF2C) were analyzed by realtime quantitative PCR (qRT-PCR).Two weeks after transfection,the expressions of cardiac-specific connexin 43 (Cx43) and cardiac troponin T (cTnT) in Ad-wnt5a-induced CP15-5a cells were detected by Western blotting and immunofluorescence techniques.The sodium current expression (INa) was detected by whole cell patch clamp techniques.Results The transfection efficiency of Ad-wnt5a and Ad-GFP was 42.8％ and 44.3％,respectively.One week after transduction,the expressions of GATA4 and MEF2C were significantly higher in wnt5a group (1.717 ± 0.220 and 1.847 ± 0.190) than in GFP group (1.003 ± 0.087 and 0.456 ± 0.042,P＜0.05) and blank control group (0.961 ± 0.063 and 0.500 ± 0.095,P＜0.05),while no significant difference existed between GFP group and blank control group.Two weeks after transduction,the expressions of CX43 and cTnT were significantly higher in wnt5a group (1.597 ± 0.267 and 0.727 ± 0.100) than in GFP group (0.723 ± 0.047 and 0.217 ± 0.021,P＜0.05) and blank control group (0.783 ± 0.1333 and 0.253 ± 0.102,P＜0.01),while no significant difference existed between GFP group and blank control group.INa was detected in the wnt5a group compared with GFP group and blank control group.Conclusion wnt5a may induce differentiation of cp 15-5a cell into myocardial cell.

Red ginseng and cancer treatment / 中国天然药物

The ginseng family, including Panax ginseng (Asian ginseng), Panax quinquefolius (American ginseng), and Panax notoginseng (notoginseng), is commonly used herbal medicine. White ginseng is prepared by air-drying after harvest, while red ginseng is prepared by a steaming or heating process. The anticancer activity of red ginseng is significantly increased, due to the production of active anticancer ginsenosides during the steaming treatment, compared with that of white ginseng. Thus far, anticancer studies have been mostly focused on Asian ginseng. In this article, we review the research progress made in the anticancer activities of red Asian ginseng, red American ginseng and red notoginseng. The major anticancer mechanisms of red ginseng compounds include cell cycle arrest, induction of apoptosis/paraptosis, and inhibition of angiogenesis. The structure-function relationship analysis has revealed that the protopanaxadiol group ginsenosides have more potent effects than the protopanaxatriol group. Sugar molecules in ginsenosides inversely impact the antiproliferative potential of these compounds. In addition, ginsenoside stereoselectivity and double bond position also influence the anticancer activity. Future studies should focus on characterizing active red ginseng derivatives as potential anticancer drugs.

Inhibition of HBV replication and antigen expression by RNA interference against different targets / 中华肝脏病杂志

<p><b>OBJECTIVES</b>To observe the inhibition of HBV replication and antigen expression by RNA interference aimed at different parts of the HBV genome.</p><p><b>METHODS</b>Following the rules of shRNA expression vector design and construction, we constructed seven kinds of sequence specific vectors and two kinds of mutant shRNA expression ones. We then cotransfected those shRNA and HBV expression vectors into HepG2 cells using lipofectamine2000. The level of HBV replication was investigated using Southern blot and the antigen expression using ELISA.</p><p><b>RESULTS</b>The replication of HBV DNA was inhibited by many shRNAs, especially the ones against P1, S2, C2, S1 and X. The inhibition rate against P1 was as high as 95%. Results obtained with ELISA showed that the shRNAs targeting C2, C1 and S2 had high rates of inhibition to HBsAg.</p><p><b>CONCLUSION</b>The replication and antigen expression of HBV could be inhibited by shRNAs aimed at four different open read frames, and higher inhibition rates of HBV replication and surface antigen expression could be obtained by P1 and C2, respectively.</p>

Potent and specific inhibition of SARS-CoV antigen expression by RNA interference / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Severe acute respiratory syndrome (SARS) is an infectious disease caused by SARS-CoV. There are no effective antiviral drugs for SARS although the epidemic of SARS was controlled. The aim of this study was to develop an RNAi (RNA interference) approach that specifically targeted the N gene sequence of severe acute respiratory syndrome associated coronavirus (SARS-CoV) by synthesizing short hairpin RNA (shRNA) in vivo, and to assess the inhibitory effect of this shRNA on SARS-CoV N antigen expression.</p><p><b>METHODS</b>The eukaryotic expression plasmid pEGFP-C1-N, containing SARS-CoV N gene, was co-transfected into 293 cells with either the RNAi plasmid pshRNA-N or unrelated control plasmid pshRNA-HBV-C4. At 24, 48 and 72 hours post transfection, the green fluorescence was observed through a fluorescence microscope. The RNA levels of SARS-CoV N were determined by reverse transcription polymerase chain reaction (RT-PCR). The expression of Green Fluorescent Protein (GFP) and protein N were detected using Western blot.</p><p><b>RESULTS</b>The vector, pshRNA-N expressing shRNA which targeted the N gene of SARS-CoV, was successfully constructed. The introduction of RNAi plasmid efficiently and specifically inhibited the synthesis of protein N. RT-PCR showed that RNAs of N gene were clearly reduced when the pEGFP-C1-N was cotransfected with pshRNA-N, whereas the control vector did not exhibit inhibitory effect on N gene transcription.</p><p><b>CONCLUSIONS</b>Our results demonstrate that RNAi mediated silencing of SARS-CoV gene could effectively inhibit expression of SARS-CoV antigen, hence RNAi based strategy should be further explored as a more efficacious antiviral therapy of SARS-CoV infection.</p>