In vivo gene transfer methods into bladder without viral vectors

目的基因治疗已成为治疗癌症的一种新策略。当考虑将其应用于膀胱癌时，安全、高效和可重复的体内基因转移方法是必不可少的。在这里，我们研究了三种没有病毒载体的体内基因转移方法。材料与方法将具有膜融合活性的日本血凝病毒（HVJ）脂质体腔内注入大鼠膀胱。用粒子枪对兔膀胱粘膜进行dna包被金微载体轰击。粘膜下注射DNA溶液后，用针电极间产生的脉冲直流电（0.15-0.2 A, 50msec，重复8次）对兔膀胱进行电转染。以-半乳糖苷酶基因和氯霉素乙酰转移酶（CAT）基因作为标记基因。结果hvj脂质体有效转染尿路上皮浅层，在第5天达到表达高峰。粒子枪在尿路上皮较深层产生了不均匀但有效的转染。转染粘膜下间质细胞和尿上皮细胞。三种方法均未见重大并发症。结论hvj脂质体在原位癌治疗中具有潜在的应用价值。经过进一步完善，后两种方法可能适合于局部膀胱肿瘤的辅助治疗。

objective GEne therapy has been adapted as a new strategy for treating cancers. When considering this application to bladder cancer, safe, efficient and repeatable in vivo geno transfer metods are essential. Here, we examined three in vivo gene transfer methods without viral vectors.Materials and methods Hemagglutinating virus of Japan (HVJ)-liposomes possessing the membrane fusion activity were intraluminally injected into rat bladders. Using a particle gun, rabbit bladder mucosa was bombarded with DNA-Coated gold microcarriers. Electrotransfection was also examined in rabbit bladder by pulse direct currents (0.15-0.2 A, 50msec, repeated 8 times) generated between needle electrodes after submucous injection of DNA solution. beta-galactosidase gene and chloramphenicol acetyl-transferase (CAT) gene were used as marker genes.Results HVJ-liposomes efficiently transfected superficial layrs of urothelium with a peak of expression on day 5. The particle gun produced non-uniform but efficient transfection in deeper layrs of the urothelim. By electransfection, submucous interstitial cells were transfected as well as urothelim. No major complications were observed in these three metheds.Conclusion HVJ-liposomes are potentially useful for treating carcinoma in situ. With further refinement, the latter two methods may be suitable for adjuvant therapies in treating localized bladder tumors.