大鼠正常脑组织伽玛刀照射后VEGF表达的实验研究

目的研究伽玛刀(γ-刀)立体定向放射外科照射大鼠正常脑组织后亚急性期血管内皮细胞生长因子(VEGF)随时间变化的表达,探讨VEGF与放射损伤的关系。方法30只Wistar大鼠,随机分为6组,每组5只。其中1组为假照射组,其余5组行γ-刀照射。运用Leksell23004B型γ-刀4 mm准直器以50Gy照射大鼠右侧尾壳核。不同组别的大鼠分别在照射后1、2、4、8、12周深度麻醉下断头取出脑组织,行免疫组织化学染色观察VEGF的表达。结果假照射组及照射后1、2周靶区内无VEGF阳性细胞：照射后4周靶区发现有少数细胞呈弱阳性表达；照射后8周时可见照射侧VEGF阳性细胞数目增加；照射后12周可见VEGF阳性细胞进一步增多。结论γ-刀放射外科以50Gy照射大鼠单侧尾壳核后,照射靶区VEGF出现阳性表达,并且随时间延长呈增高趋势。     

白藜芦醇对U251人胶质瘤细胞抑制生长作用的研究

白藜芦醇（Res）是一种广泛存在于植物中的植物补体。而Res对胶质瘤的抑瘤作用报道甚少，近年来有关胶质瘤的大量的研究证实，表皮生长因子受体（EGFR）介导的信号转导通路在恶性胶质瘤发生、发展中发挥着关键的作用。本实验进一步就Res对U251脑胶质瘤细胞生长增殖的抑制、诱导细胞凋亡及其与胶质瘤增殖及其相关机制进行了探讨。     

脑膜瘤的伽玛刀放射外科治疗

目的：总结评价伽玛刀放射外科治疗颅内脑膜瘤的效果。方法：８０例患者年龄１６￣８１岁,平均５２．２０岁;男２５例,女５５例。病史０．５￣１６８个月,平均３４．８６个月,中位时间为１５个月。２４例为手术后复发或残留,肿瘤容积为０．８８￣３５．９０ｍｌ,平均１０．５７ｍｌ。局麻下立体定向强化ＭＲＩ定位。应用边缘剂量１０￣２０Ｇｙ,平均１４．２７Ｇｙ。中心剂量２２．５￣４０Ｇｙ,平均２９．４０Ｇｙ。等剂量     

颅内囊性肿瘤伽玛刀治疗的容积效应

评价颅内囊性肿瘤经立体定向抽液前后容积变化在伽玛刀治疗中的作用。方法：对３９例颅内囊性肿瘤ＭＲＩ定位后,确定穿刺道和靶点坐标,采用立体定向技术抽吸瘤内囊液使肿瘤社会公德只缩小,然后二次ＭＲＩ室位行伽玛刀治疗。边缘剂量为１０－２５Ｇｙ,平均１５．１７Ｇｙ。确定３％风险概率为警戒线,应用Ｌｏｇｉｓｔｉｃ综合方程（Ｎｅｕｒｅｔ）分析剂量－容积关系和应用平均剂量１５Ｇｙ的社会公德只－风险概率的相关性。将抽     

腺病毒介导的靶向P85和Akt1短发夹RNA对人胃腺癌细胞生长抑制作用的研究

目的 构建靶向P85和蛋白激酶B1(PKB1/Akt1)的短发夹RNA(shRNA)腺病毒载体,研究其对人胃腺癌细胞SGC-7901生长的抑制效果.方法 构建腺病毒载体rAd5-P+A,体外转染SGC-7901细胞后,以实时定量PCR和Western blot分别检测P85和Akt1的mRNA和蛋白质的表达.以噻唑蓝比色分析法(MTT法)和流式细胞法评价转染后胃癌细胞的增殖活性.构建裸鼠皮下荷瘤模型进一步观察rAd5-P+A对SGC-7901细胞生长的抑制效果,并应用原位末端标记技术(TUNEL法)检测肿瘤细胞的凋亡情况.结果 成功构建的rAd5-P+A重组腺病毒载体转染SGC-7901细胞后可显著抑制p85和Akt1的mRNA表达,而P85和Aktl蛋白表达量在转染48 h、72 h后分别下调57.5%、63.7%和67.8%、75.6%,与空白对照组和通用腺病毒对照(rAd5-HK)组相比,差异具有统计学意义(P=0.005,P=0.003).与空白对照组和rAd5-HK组相比,SGC-7901细胞的增殖活性在rAd5-P+A转染后第2天明显下降(P<0.001),且rAd5-P+A转染组进入S期的细胞数减少了5.9%～7.1%,而进入G0/G1期的细胞增加了12.1%～13.7%.裸鼠皮下荷瘤模型治疗实验也显示,rAd5-P+A可抑制胃癌细胞的生长,诱导细胞的凋亡.结论 腺病毒介导的靶向P85和Akt1的shRNA可抑制人胃腺癌细胞的生长,这可能为胃腺癌靶向性联合基因治疗提供新的策略.     

靶向性蛋白激酶B1和环氧合酶-2 shRNA腺病毒载体的构建和在人胃癌细胞的表达

Objective To construct a short hairpin RNA (shRNA) adenovirus vector targeting protein kinase BI (PKB1/Akt1) and cyclooxygenase-2 (COX-2) and observe their expression in human gastric carcinoma cell line SGC-7901. Methods Akt1 and COX-2 shRNA expression frames were sub-cloned to pGSadeno adenovirus vector by homologous recombination technology to construct pGSadeno-Aktl + COX-2 ( pGSadeno-A + C) vector. Furthermore after screening and amplification,recombinant ade-novirus vector was digested with Pacl and transfected into HEK293 cells. The replication adenovirus rAd5-A + C was packed and amplified in the HEK293 cells, and its titer was detected. After human SGC-7901 cells in vitro were transfected by rAd5-A + C,Akt1 and COX-2 mRNA and protein expression levels were detected by real-time PCR and Western blot respectively. Compared with rAdS-A + C,SGC-7901 and gen-eral rAd5-HK were selected as the negative controls. Results The recombinant adenovirus rAd5-A + C was constructed successfully and its titer reached 1.0 ×1010 pfu/ml. Aktl and COX-2 mRNA expression was downregulated significantly, and their ACt values ( 12.26±0.05 and 5.41±0.09 respectively ) were higher than rAd5-HK group (10.63±0.02 and 3.75 +0.08 respectively) and control group (10.57± 0.02 and 3.73±0.08 respectively) (P <0.01 ). There was no significant difference between rAd5-HK and control groups (P >0.05). Aktl and COX-2 protein expression was downregulated by 70.5% and 63.7% respectively ( P < 0.01 ) in rAd5-HK group as compared with control group ( P > 0.05 ). Conclu-sion The shRNA aclenovirus vector targeting Akt1 and COX-2 can specifically inhibit Akt1 and COX-2 expression,and this may be a new strategy in gastric carcinoma gene therapy targeting Akt1 and COX-2.     

PTEN基因治疗鼠C6胶质瘤的体内实验研究

目的 探讨PTEN基因在动物体内对脑胶质瘤的生长作用。方法 将大鼠C6胶质瘤细胞（对照组）和转染PTEN cDNA的C6细胞（转染组）种植于SD大鼠右侧尾状核。荷载C6脑胶质瘤鼠用PTEN cDNA原位治疗（治疗组）。并以空载体治疗作为对照（空载组）。每组10只。观察大鼠的一般情况、生存期、肿瘤体积变化以及肿瘤病理组织学与细胞生物学特征变化。结果 对照组和空载组大鼠均于3周内死亡。而转染组5只大鼠和治疗组6只大鼠观察60d内无自然死亡，生存期较对照组明显延长（P〈0．01）。结论 PTEN基因在动物体内可以抑制脑胶质瘤的生长。可以成为恶性胶质瘤基因治疗的优选靶之一。     

RNA干扰技术靶向P13K/AKT信号通路抵制胃腺癌SGC7901细胞侵袭转移的研究

Objective To observe the inhibitory effects on the invasion of gastric adenocarcinoma SGC7901 cells by small hairpin RNA targeting PIK3R1 and AKT1 in vitro. Methods The recombinant adenovirus vector plasmid expression vector which contained PIK3R1 and AKT1 shRNA was transfected into SGC7901 cells. Real time PCR and Western blot were used to detect the expression of P1K3R1 and AKT1. ELESA was used to measure the change in the MMP-2 and MMP-9 expression. The invasion ability of the tumor ceils was examined by Scarification, Transwell and 3-dimensional matrigel matrix tests. Re-sults rAdS-A-P mediated shRNA targeting PIK3R1 ,and AKT1 dramatically down-regulated their expres-sion in SGC7901 cells. MMP-2 and MMP-9 were downregulated,and TIMP-2 was upregulated. The extra-cellular levels of MMP-2 and MMP-9 were decreased. Scarification test indicated that the invision ability was decreased obviously. Transwell showed that the number of cells invading through the matrigel in con-trol. nonsense sequence, and rAd5-A-P transfection groups was 105.0±4.0,102.5±6.4, and 67.0±3.9 respectively. In the rAdS-A-P transfection group, cells formed only small aggregates as compared with the control and nonsense sequence groups in 3-dimensional matrigel matrix growth test. Conclusion ShRNA targeting PIK3R1 ,and AKTI downregulated significantly their expression in a sequence-specific manner, and inhibited the invasion of gastric adenocarcinoma SGC7901 cells in vitro.     

RNA干扰技术靶向P13K/AKT信号通路抵制胃腺癌SGC7901细胞侵袭转移的研究

Objective To observe the inhibitory effects on the invasion of gastric adenocarcinoma SGC7901 cells by small hairpin RNA targeting PIK3R1 and AKT1 in vitro. Methods The recombinant adenovirus vector plasmid expression vector which contained PIK3R1 and AKT1 shRNA was transfected into SGC7901 cells. Real time PCR and Western blot were used to detect the expression of P1K3R1 and AKT1. ELESA was used to measure the change in the MMP-2 and MMP-9 expression. The invasion ability of the tumor ceils was examined by Scarification, Transwell and 3-dimensional matrigel matrix tests. Re-sults rAdS-A-P mediated shRNA targeting PIK3R1 ,and AKT1 dramatically down-regulated their expres-sion in SGC7901 cells. MMP-2 and MMP-9 were downregulated,and TIMP-2 was upregulated. The extra-cellular levels of MMP-2 and MMP-9 were decreased. Scarification test indicated that the invision ability was decreased obviously. Transwell showed that the number of cells invading through the matrigel in con-trol. nonsense sequence, and rAd5-A-P transfection groups was 105.0±4.0,102.5±6.4, and 67.0±3.9 respectively. In the rAdS-A-P transfection group, cells formed only small aggregates as compared with the control and nonsense sequence groups in 3-dimensional matrigel matrix growth test. Conclusion ShRNA targeting PIK3R1 ,and AKTI downregulated significantly their expression in a sequence-specific manner, and inhibited the invasion of gastric adenocarcinoma SGC7901 cells in vitro.