Integrinβ1 asODN-inhibition of Cell Attachment and Invasion of the Human Gastric Cancer Cell Line SGC7901

OBJECTIVE To study the inhibition of adhesion and invasion of SGC7901cells into the ECM by integrinβ1 antisense oligodeoxynucleotide asODN.METHODS asODN and control ODN were transfected into SGC7901 cells using liposomes as vectors. The distribution of the ODN was followed by immunochemistry and changes in the expression of integrinβ1 mRNA and protein were determined by RT-PCR and FCM, respectively. The adhesion and invasion into the ECM were measured by the MTT and Boyden chamber methods, respectively.RESULTS Integrinβ1 asODN which was transfected into SGC7901 cells distributed evenly in the cytoplasm and nucleus. PCR and FCM revealed a weakened band at 489bp and a left-shift curve, respectively. Adhesion and invasion assays showed decreased activity with an inhibition rate of 54% and 76%. The extent of decrease induced by integrinβ1 asODN was larger than that caused by random control ODN (P＜0.001).CONCLUSION Transfection of integrinβ1 asODN into SGC7901 cells induced a decrease in the expression of integrinβ1 mRNA and protein,resulting in a decrease in adhesion and invasion into the ECM, with a greater effect than random control ODN.     

反义寡核苷酸聚甲基丙烯酸酯亚微粒入胞行为的研究反义寡核苷酸聚甲基丙烯酸酯亚微粒入胞行为的研究

反义寡核苷酸(antisense oligodeoxynucleotides,AS-ODN)是一种能与特定的DNA或RNA特异性结合并阻断基因表达的生物效应分子,具有作用强、特异性高等优点,受到广泛关注[1]。然而由于AS-ODN为亲水性大分子,细胞通透性差,使得它的应用受到极大限制。为了增加AS-ODN在体内的稳定性     

联合新型Bcl-2反义核酸与足叶乙苷抑制人小细胞肺癌细胞的增殖

目的　研究一种新型Bcl 2反义寡核苷酸 F95 1在与足叶乙苷 (VP16 )联合使用时 ,对人小细胞肺癌细胞增殖的影响。方法　分别单独及联合应用F95 1、VP16于人小细胞肺癌细胞株NCI H4 4 6 ,通过MTT法检测细胞存活率 ,通过集落形成法检测集落生存率 ,按Welander法计算联合应用组的预测值 ,通过实测值与预测值的比较进行效应分析。结果　细胞存活率 (MTT法 )和集落生存率 (集落形成法 )均显示联合应用F95 1、VP16组的实测值明显低于预测值。结论　联合应用F95 1与VP16对人小细胞肺癌细胞的增殖有协同的抑制作用。     

Rb反义寡核苷酸对人结肠癌细胞凋亡及化疗药敏的影响

目的　观察Rb反义寡核苷酸 (AS ODN)对人结肠癌(HT 2 9)细胞凋亡及化疗药物敏感性的影响。方法　人工合成RbAS ODN经脂质体 (Lip)包裹后作用HT 2 9细胞。采用免疫组化、WesternBlot检测转染前后Rb蛋白表达状况 ,流式细胞术测定HT 2 9细胞转染前后 5 Fu诱导凋亡程度 ,MTT法观察化疗药敏的变化。结果　经RbAS ODN处理的HT 2 9细胞Rb蛋白表达量明显下降 ,RbAS ODN处理的HT 2 9细胞加 5 Fu作用后与对照组比较 ,细胞凋亡率明显下降 ,化疗药物敏感性降低。结论　RbAS ODN阳离子脂质体转染具有抑制化疗药诱导大肠癌HT 2 9细胞凋亡的作用及降低化疗药物敏感性作用。     

β1肾上腺素能受体反义寡核苷酸对肾性高血压大鼠血流动力学及心肌肥厚的影响

目的 :观察阳离子脂质体 (DOTAP DOPE)介导的 β1肾上腺素能受体mRNA反义寡核苷酸 (β1 AS ODN)对肾性高血压大鼠血流动力学及心肌肥厚的影响。方法 :建立二肾一夹 (2K1C)肾性高血压大鼠模型 ,随机分为假手术组、模型组、反向寡核苷酸组、反义寡核苷酸组和卡维地洛 (carvedilol)组。ODN与DOTAP DOPE以 1 2摩尔比混合 ,4周末尾静脉注射 0 .5mg·kg-1,卡维地洛 10mg·kg-1·d-1灌胃 4周。定期测血压 ,8周末测血流动力学参数 ,左室重量指数 (LVWI)及血浆内皮素 1(ET 1)浓度 ,并对LVWI与ET 1进行线性相关分析。结果 :与反向寡核苷酸组比 ,β1 AS ODN能降低血压最高达39mmHg并持续 2 7d(30 .4 4± 6 .5 0 ,P <0 .0 1) ,降低左室收缩压 (LVSP) (P <0 .0 5 )、左室舒张末压 (LV EDP) (P <0 .0 1) ,升高左室最大收缩和舒张速率 (±dp dtmax) (P <0 .0 1) ,降低LVWI(P <0 .0 5 )及血浆ET 1(P <0 .0 1) ;与卡维地洛组比 ,各指标均无显著性差异。LVWI与ET 1显著正相关 (r =0 .74 9,P <0 .0 1)。结论 :DOTAP DOPE介导的 β1 AS ODN单剂量静脉注射能持续降压 ,改善血流动力学 ,预防心肌肥厚 ,可能与其降低血浆ET 1有关。     

Local and systemic tolerability of a 2′O-methoxyethyl antisense oligonucleotide targeting interleukin-4 receptor-α delivery by inhalation in mouse and monkey

Abstract

Antisense oligonucleotides (ASOs) bind and facilitate degradation of RNA and inhibit protein expression in pathways not easily targeted with small molecules or antibodies. Interleukin (IL)-4 and IL-13 potentiate signaling through the shared IL-4 receptor-α (IL-4Rα) subunit of their receptors. ASO targeting of IL-4Rα mRNA in a mouse model of asthma led to attenuation of airway hyperactivity, demonstrating potential benefit in asthma patients. This study focused on tolerability of inhaled IL-4Rα-targeting ASOs. Toxicity studies were performed with mouse- (ISIS 23189) and human-specific (ISIS 369645) sequences administered by inhalation. Four week (monkey) or 13 week (mouse) repeat doses at levels of up to 15?mg/kg/exposure (exp) and 50?mg/kg/exp, respectively, demonstrated dose-dependent effects limited to increases in macrophage size and number in lung and tracheobronchial lymph nodes. The changes were largely non-specific, reflecting adaptive responses that occur during active exposure and deposition of ASO and other material in the lung. Reversibility was observed at a rate consistent with the kinetics of tissue clearance of ASO. Systemic bioavailability was minimal, and no systemic toxicity was observed at exposure levels appreciably above pharmacological doses and doses proposed for clinical trials.     

Targeted therapies for the myeloid leukaemias

Although the standard approach to myeloid leukaemias remains chemotherapy, the agents currently available rarely result in cure. Recent advances in understanding the biology of these disorders have lead to the development of targeted treatment strategies. In acute promyelocytic leukaemia (APL), all-trans retinoic acid (ATRA), sodium phenylbutyrate and arsenic trioxide are agents which either induce differentiation or apoptosis and have been used to successfully achieve remission. The tyrosine kinase inhibitor, STI-571, antisense oligonucleotides, and bcr-abl vaccines are strategies which focus on the oncogenic events in chronic myelogenous leukaemia (CML). Two anti-CD33 monoclonal antibody conjugates, Y90-HuM195 and CMA-676, have been used in acute myelogenous leukaemia (AML) and have shown some efficacy. Although the preliminary results with these targeted therapies are promising, further studies are needed to establish them as effective, less toxic alternatives to the current standard of care.     

Cytotoxic effects and specific gene expression alterations induced by I-125-labeled triplex-forming oligonucleotides

Abstract

Purpose: Triplex-forming oligonucleotides (TFO) bind to the DNA double helix in a sequence-specific manner. Therefore, TFO seem to be a suitable carrier for Auger electron emitters to damage exclusively targeted DNA sequences, e.g., in tumor cells. We studied the influence of I-125 labeled TFO with regard to cell survival and induction of DNA double-strand breaks (DSB) using TFO with different genomic targets and target numbers. Furthermore, the ability of TFO to alter the gene expression of targeted genes was examined.

Materials and methods: TFO were labeled with I-125 using the primer extension method. DNA triplex formation and sequence-specific DSB were demonstrated in vitro. Cell survival was analyzed by colony-forming assay and DNA damage was assessed by microscopic quantification of protein 53 binding protein 1 (53BP1) foci in the human squamous carcinoma cell line II (SCL-II). Quantitative real-time polymerase-chain-reaction (qRT-PCR) was performed to analyze gene expression alterations.

Results: The sequence-specific induction of a single DSB in a 1695 bp long DNA double stranded fragment was demonstrated in vitro. I-125-labeled TFO binding to single and multiple targets were shown to induce a pronounced decrease in cell survival and an increase of DSB. TFO targeting multiple sites differing in the total target number showed a significant different cell killing per decay that is also in good accordance with the observed induction of DSB. Single gene targeting I-125-labeled TFO significantly decreased cell survival and altered gene expression in the targeted gene.

Conclusions: I-125-labeled TFO enable specific targeting of DNA in vitro as well as in a cellular environment and thus induce sequence-specific complex DNA lesions. Therefore I-125-labeled TFO might be a very useful tool for basic DNA repair research.     

Challenges posed to the European pharmaceutical regulatory system by highly personalized medicines

The European pharmaceutical regulatory system has not yet been challenged by issues related to highly personalized medicines such as those to be found with active substances that affect RNA biochemistry. We review the current status of RNA-based pharmacology and present three possible case histories. The implications for the European pharmaceutical regulatory system are discussed.