自杀基因治疗鼠C6脑胶质瘤模型的动态MRI研究

The Therapeutic Effect of Suicide Gene on Rat C6 Glioma Model Dynamic Observation with HR MRI

目的：用高分辨ＭＲＩ动态观察携带ＨＳＶＴＫ自杀基因的逆转录病毒载体及ＧＣＶ治疗系统对在体大鼠Ｃ６脑胶质瘤模型的治疗效果及ＭＲＩ表现的演变规律。材料与方法：３６只ＳＤ大鼠，使用颅内立体定向接种法制作模型。按接种细胞类型分４组：①Ｃ６胶质瘤；②Ｃ６ｔｋ；③Ｃ６＋Ｃ６ｔｋ（１∶１）；④Ｃ６＋ＰＡ３１７ｔｋ。瘤龄７天后腹腔注射ＧＣＶ３０ｍｇ／ｋｇ／天，共１４天。用１．５ＴＭＲ机行Ｔ１ＷＩ、Ｔ２ＷＩ和增强扫描，１次／１～２周；并行常规病理、免疫组化（ＧＦＡＰ和Ｓ１００蛋白）、凋亡和电镜检查。结果：ＭＲＩ显示①组瘤龄１４天时病灶呈圆形长Ｔ１长Ｔ２信号，明显强化，中心见坏死区，肿瘤平均１９６ｍｍ３，中位存活期１６天。②～④组，自然存活期大于１８０天，１４天时病灶平均体积３５ｍｍ３；２８天时肿瘤消失率８０％，１８０天肿瘤消失率９３％。结论：１．５ＴＭＲ扫描可清楚显示肿瘤的大小、形态和内部结构，与病理结果高度相关；

Objective: To evaluate the therapeutic effect of retrovirus vector, bearing Herpes Simplex Virus Thymidine Kinase Gene and Ganciclovir (HSV TK/GCV) System, on rat C6 glioma model, observed dynamically with high resolution MR imaging.Materials and Methods: Thirty six adult Spraque Dawley rats weighing 150～200g were divided into four groups: ①C6 glioma group (〖WT5”BX〗n〖WT5”BZ〗=6); ②C6tk group (〖WT5”BX〗n〖WT5”BZ〗=10); ③C6+C6tk (1∶1) group n=10); ④C6+PA317tk group (〖WT5”BX〗n〖WT5”BZ〗=10). When the tumor was 7 days old, 30mg/kg/day of GCV was intraperitoneally injected for 14 days. T 1WI, T 2WI and enhanced MR scanning with a 1.5T MR unit were performed on all rats, reexamined every 1 or 2 weeks. Twenty rats were sacrificed at different experimental day and pathological examination was made.Results:MRI clearly showed the changing sequences of the lesion after treatment. In group ②, ③ and ④, the tumors regressed significantly, or even disappeared in some cases.Conclusion: 1.5T MR scan unit can clearly show the size, configuration and inner structure of rat C6 glioma lesion, which were highly correlated with histopathological findings, thus, MRI can be used to observe and confirm the therapeutic effect of HSV TK/GCV.