Aiqiang Dong

Tumor-targeting magnetic lipoplex delivery of short hairpin RNA suppresses IGF-1R overexpression of lung adenocarcinoma A549 cells in vitro and in vivo.

Liposomal magnetofection potentiates gene transfection by applying a magnetic field to concentrate magnetic lipoplexes onto target cells. Magnetic lipoplexes are self-assembling ternary complexes of cationic lipids with plasmid DNA associated with superparamagnetic iron oxide nanoparticles (SPIONs). Type1 insulin-like growth factor receptor (IGF-1R), an important oncogene, is frequently overexpressed in lung cancer and mediates cancer cell proliferation and tumor growth. In this study, we evaluated the transfection efficiency (percentage of transfected cells) and therapeutic potential (potency of IGF-1R knockdown) of liposomal magnetofection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshIGF-1Rs) in A549 cells and in tumor-bearing mice as compared to lipofection using Lipofectamine 2000. Liposomal magnetofection provided a threefold improvement in transgene expression over lipofection and transfected up to 64.1% of A549 cells in vitro. In vitro, IGF-1R specific-shRNA transfected by lipofection inhibited IGF-1R protein by 56.1±6% and by liposomal magnetofection by 85.1±3%. In vivo delivery efficiency of the pGFPshIGF-1R plasmid into the tumor was significantly higher in the liposomal magnetofection group than in the lipofection group. In vivo IGF-1R specific-shRNA by lipofection inhibited IGF-1R protein by an average of 43.8±5.3%; that by liposomal magnetofection inhibited IGF-1R protein by 43.4±5.7%, 56.3±9.6%, and 72.2±6.8%, at 24, 48, and 72 h, respectively, after pGFPshIGF-1R injection. Our findings indicate that liposomal magnetofection may be a promising method that allows the targeting of gene therapy to lung cancer.

Effects of polyphyllin I on growth inhibition of human non-small lung cancer cells and in xenograft

Polyphyllin I (PPI), a small molecular monomer extracted from Rhizoma of Paris polyphyllin, shows strong anticancer effects in previous study. Human lung adenocarcinoma A549 cells, human lung squamous cell carcinoma SK-MES-1 cells, and human lung large cell carcinoma H460 cells were cultured and then treated with PPI. Cell proliferation and apoptosis were measured by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, flow cytometry, western blot analysis, and DNA ladder. Athymic nude mice bearing tumors were injected with PPI, and tumor growth was recorded. Our results showed that PPI significantly inhibited the proliferation of three non-small cell lung cancer (NSCLC) cell lines, with the inhibitory concentrations (IC50) of 1.24, 2.40, and 2.33 μg/ml for A549, H460, and SK-MES-1 cells, respectively. After being treated with 2.5 µg/ml of PPI for 24 h, the apoptotic rate of A549 cells was 39.68%, which was remarkably higher than that of the control. Tumor growth was significantly inhibited in the PPI-treated group compared with the group treated with cisplatin (DDP) or PBS in the nude mice. PPI exhibits antitumor ability in NSCLC cells in vitro and in vivo, which might be related to the apoptosis induced by PPI.

Down-regulation of IGF-IR using small, interfering, hairpin RNA (siRNA) inhibits growth of human lung cancer cell line A549 in vitro and in nude mice

Type I insulin‐like growth factor receptor (IGF‐IR), which is frequently overexpressed in a variety of human cancers including lung cancer, mediates cancer cell proliferation and tumor growth. In this study, we used a human U6 promoter‐driven DNA‐template approach to induce hairpin RNA (hpRNA)‐triggered RNAi to silence IGF‐IR gene expression in the human lung cancer cell line A549, and then evaluate its effects on apoptosis, apoptosis‐related gene expression, and the growth of tumor cells in vitro and in nude mice. IGF‐IR expression levels were found to markedly decrease in cells transfected with a plasmid expressing hairpin siRNA for IGF‐IR (by more than 78.9%). Down‐regulation of IGR‐IR concomitantly accompanied reduction of bcl‐2 as well as pERK and pAkt levels, activation of caspase‐3, apoptosis and growth inhibition of A549 cells in vitro. Direct intratumoral injections of plasmid DNA expressing hpRNA for IGF‐IR significantly regressed pre‐established tumors in nude mice. Our results support the therapeutic potential of RNAi as a method for gene therapy in treating lung cancer.

Comparison 30-day clinical complications between transfemoral versus transapical aortic valve replacement for aortic stenosis: a meta-analysis review

BackgroundSince 2002, transapical aortic valve replacement has been developed as a clinical pathway for transcatheter aortic valve implantation (TAVI). However the appropriate role of TA in the AS population versus TF remains unclear. We performed a meta-analysis to assess if TF has any benefit in reduction of 30-day clinical complications in AS.MethodsWe conducted a comprehensive search on pub-med and web of knowledge from 2002 through September 2012 using following terms: aortic stenosis, aortic valve replacement, transcatheter aortic valve implantation, TAVI, trans-artery, transfemoral, trans-apical. Studies in the original research or review articles were also considered. Included studies must meet the preconditioned criterias. Two investigators independently browsed the studies by title and abstract, finally making decision according to full-text. Disagreements were discussed in group.ResultsA total of 20 studies met inclusion criteria’s and were included in the analysis (including 4267 patients in TF group, 2242 in TA group). No random clinical trial, one was a retrospective study, others were prospective trials. Our meta-analysis found that TF had the low incidence of 30-day mortality compared with TA procedure (7.5% versus 11.3%). The incidence of stroke at ≤ 30 days was relatively low (3.8% in TF versus 4.0% in TA). Although the incidence of post-operative heart block was high (8.5% versus 7.5%), but no differences were indicated [1.06,95% CI(0.85,1.33)].ConclusionsThe result of our meta-analysis suggested that TF may have a low risk for 30-day mortality against TA procedure. No difference was found in the incidence of post-operative stroke and heart block.

Evaluation of the safety and efficacy of transcatheter aortic valve implantation in patients with a severe stenotic bicuspid aortic valve in a Chinese population

ObjectiveThe purpose of this study is to evaluate the safety and efficacy of transcatheter aortic valve implantation (TAVI) in patients with a severe stenotic bicuspid aortic valve (BAV) in a Chinese population. While several groups have reported the feasibility, efficacy, and safety of TAVI for patients with a BAV, worldwide experience of the technique is still limited, especially in China.MethodsFrom March 2013 to November 2014, high surgical risk or inoperable patients with symptomatic severe aortic stenosis (AS) who had undergone TAVI at our institution were selected for inclusion in our study. Results were compared between a BAV group and a tricuspid aortic valve (TAV) group.ResultsForty patients were included in this study, 15 (37.5%) of whom were identified as having a BAV. In the BAV group, the aortic valve area was smaller ((0.47±0.13) vs. (0.59±0.14) cm2), the ascending aortic diameter was larger ((40.4±4.4) vs. (36.4±4.3) mm), and the concomitant aortic regurgitation was lower. No significant differences were found between the groups in the other baseline characteristics. No differences were observed either in the choice of access or valve size. The procedural success achieved in this study was 100%. There were no differences between groups in device success (86.7% vs. 88.0%), 30-d mortality (6.7% vs. 8.0%), or 30-d combined end point (13.3% vs. 12.0%). The incidences of new pacemaker implantation, paravalvular regurgitation and other complications, recovery of left ventricle ejection fraction and heart function were similar in both groups.ConclusionsPatients with a severely stenotic BAV can be treated with TAVI, and their condition after treatment should be similar to that of people with a TAV.摘要目的评估经导管主动脉瓣置入术在中国人群二叶式主动脉瓣重度狭窄中的安全性和有效性。创新点首次在中国人群比较经导管主动脉瓣置入术在二叶式和三叶式主动脉瓣重度狭窄中的安全性和有效性。方法选取2013年3月至2014年9月行经导管主动脉瓣置入术的40位主动脉瓣狭窄的患者, 分二叶式和三叶式主动脉瓣两组, 比较基线水平、 手术以及随访1月结果的差别。结论经导管主动脉瓣置入术在中国人群中二叶式主动脉瓣重度狭窄中的应用是安全有效的。

MicroRNA-150 aggravates H2O2-induced cardiac myocyte injury by down-regulating c-myb gene

MicroRNAs (miRNAs) are one class of non-coding RNAs that play an important role in post-transcriptional regulation via the degradation or translational inhibition of their target genes. MicroRNA-150 (miR-150) plays a vital role in regulating the development of B and T lymphocytes. Although the dysregulation of miR-150 was confirmed in human myocardial infarction, little is known regarding the biological functions of miR-150 in response to reactive oxygen species (ROS)-mediated gene regulation in cardiac myocytes. Using quantitative real-time reverse transcription-polymerase chain reaction, we demonstrated that the level of miR-150 was up-regulated in cardiac myocytes after treatment with hydrogen peroxide (H2O2). To identify the potential roles of miR-150 in H2O2-mediated gene regulation, we modulated expression of miR-150 using miR-150 inhibitor and miR-150 mimics. Results showed that silencing expression of miR-150 decreased H2O2-induced cardiac cell death and apoptosis. In lymphocytes, c-myb was a direct target of miR-150. In cardiac myocytes, we found that c-myb was also involved in miR-150-mediated H2O2-induced cardiac cell death. These results suggested that miR-150 participates in H2O2-mediated gene regulation and functional modulation in cardiac myocytes. MiR-150 may play an essential role in heart diseases related to ROS, such as cardiac hypertrophy, heart failure, myocardial infarction, and myocardial ischemia/reperfusion injury.

Tissue distribution and cancer growth inhibition of magnetic lipoplex-delivered type 1 insulin-like growth factor receptor shRNA in nude mice

The targeted delivery of therapeutic genes into specific tissues, as well as the determination of the biological fate and potential toxicity of nanoparticles, remains a highly relevant challenge for gene-based therapies. Type 1 insulin-like growth factor receptor (IGF-1R), an important oncogene, is frequently over-expressed in lung cancer and mediates cancer cell proliferation as well as tumor growth. In our previous studies, we have successfully applied gene delivery mediated by commercially available nanoparticles (CombiMAG) under a magnetic field, which suppresses IGF-1R expression in a non-small cell lung cancer cell line (A549) in vitro. In the present study, we aimed to investigate the biological distribution and target tumor suppression of magnetofection, as well as its potential toxicity via CombiMAG-carrying plasmids expressing green fluorescent protein (GFP) and short hairpin RNAs (shRNAs) targeting IGF-1R (pGFPshIGF-1Rs) in tumor-bearing mice. The peak expression in various organs appeared 48 h after transfection. Transgene expression via magnetofection was 3-fold improvement than via lipofection. On the 30th day after injection, the tumor size and weight of the CombiMAG-treated group (789.32 ± 39.43 mm(3), 105.5 ± 6.1 mg) were significantly decreased compared with those of the lipofection group (893.83 ± 31.23 mm(3), 164.5 ± 9.1 mg; P< 0.05), and the suppression rate was ∼36%. After a 30-day observation, the injection of CombiMAG did not cause any apparent toxicity. Therefore, IGF-1R shRNA nanoparticles can be valuable and safe delivery agents for RNA interference therapy to tumors in vivo.

Anterolateral minithoracotomy versus median sternotomy for the treatment of congenital heart defects: a meta-analysis and systematic review

BackgroundAnterolateral Minithoracotomy (ALMT) for the radical correction of Congenital Heart Defects is an alternative to Median Sternotomy (MS) due to reduce operative trauma accelerating recovery and yield a better cosmetic outcome after surgery. Our purpose is to conduct whether ALMT would bring more short-term benefits to patients than conventional Median Sternotomy by using a meta-analysis of case–control study in the published English Journal.Methods6 case control studies published in English from 1997 to 2011 were identified and synthesized to compare the short-term postoperative outcomes between ALMT and MS. These outcomes were cardiopulmonary bypass time, aortic cross-clamp time, intubation time, intensive care unit stay time, and postoperative hospital stay time.ResultsALMT had significantly longer cardiopulmonary bypass times (8.00 min more, 95% CI 0.36 to 15.64 min, p = 0.04). Some evidence proved that aortic cross-clamp time of ALMT was longer, yet not significantly (2.38 min more, 95% CI −0.15 to 4.91 min, p = 0.06). In addition, ALMT had significantly shorter intubation time (1.66 hrs less, 95% CI −3.05 to −0.27 hrs, p = 0.02). Postoperative hospital stay time was significantly shorter with ALMT (1.52 days less, 95% CI −2.71 to −0.33 days, p = 0.01). Some evidence suggested a reduction in ICU stay time in the ALMT group. However, this did not prove to be statistically significant (0.88 days less, 95% CI −0.81 to 0.04 days, p = 0.08).ConclusionALMT can bring more benefits to patients with Congenital Heart Defects by reducing intubation time and postoperative hospital stay time, though ALMT has longer CPB time and aortic cross-clamp time.

Anterolateral minithoracotomy versus median sternotomy for mitral valve disease: a meta-analysis

Objective: Mitral valve disease tends to be treated with anterolateral minithoracotomy (ALMT) rather than median sternotomy (MS), as ALMT uses progressively smaller incisions to promote better cosmetic outcomes. This meta-analysis quantifies the effects of ALMT on surgical parameters and post-operative outcomes compared with MS. Methods: One randomized controlled study and four case-control studies, published in English from January 1996 to January 2013, were identified and evaluated. Results: ALMT showed a significantly longer cardiopulmonary bypass time (P=0.001) and aortic cross-clamp time (P=0.05) compared with MS. However, the benefits of ALMT were evident as demonstrated by a shorter length of hospital stay (P<0.00001). According to operative complications, the onset of new arrhythmias following ALMT decreased significantly as compared with MS (P=0.05); however, the incidence of perioperative mortality (P=0.62), re-operation for bleeding (P=0.37), neurologic events (P=0.77), myocardial infarction (P=0.84), gastrointestinal complications (P=0.89), and renal insufficiency (P=0.67) were similar to these of MS. Long-term follow-up data were also examined, and revealed equivalent survival and freedom from mitral valve events. Conclusions: Current clinical data suggest that ALMT is a safe and effective alternative to the conventional approach and is associated with better short-term outcomes and a trend towards longer survival.

Polymer-based delivering of shRNA to rabbit aortic smooth muscle cells suppressed the expression of IGF-1R in vitro and in vivo

Restenosis is one of clinical limitations for vein graft in coronary bypass graft. It has been proved that signal pathway IGF-1 and its receptor (IGF-1R) activated by hemodynamic mechanical stretch are responsible for the vascular smooth muscle cells proliferation in vein graft neointima formation. Unfortunately, there is no routinely successful method to resolve this problem. Gene delivering to vein graft possesses great therapeutic potential to prevent neointima formation. Polymer is one kind of nanoparticles, which can activate the process of endocytosis of cells. In this study, we evaluated the transfection efficiency and therapeutic potential of polymer-based transfection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshIGF-1Rs) to smooth muscle cells and rabbit external jugular vein graft. Results showed that polymer-based transfection provided high efficiency of transgene expression in smooth muscle cells in vitro. In vitro, IGF-1R-specific shRNA transfected by polymer inhibited IGF-1R protein expression by 52 ± 3.6%, when compared with mock transfected cells. In vivo delivering efficiency of pGFPshIGF-1R plasmid into the rabbit external jugular vein graft was significantly high in the polymer-based transfection group, when compared with negative control group. In vivo, polymer-based transfection IGF-1R-specific shRNA efficiently inhibited the expression of IGF-1R protein by 77 ± 3.6%, 65.6 ± 4.9%, and 76.7 ± 4.3% at 24, 48, and 72 h, respectively, when compared with negative control group. Our findings indicated that polymer-based transfection may be a promising technique that allows the targeting of gene therapy for vein graft restenosis.