内皮祖细胞磁共振成像活体评价经肝动脉、门静脉途径介入治疗兔门静脉癌栓的实验研究

Background:.Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world. Approximately 45% of new cases per year are in China. Approximately 67.1% of HCC were found to have PVTT by histopathological analysis. It was reported that transcatheter arterial chemoembolization (TACE) confers a survival benefit to patients of HCC with PVTT. It was deeply concerned about by interventional radiologist and surgeon that the feeding blood of PVTT is uncertain. Is the feeding blood of PVTT from hepatic artery or portal vein? Recently, emerging evidence suggests that endothelial progenitor cells (EPCs) play an important role in tumor angiogenesis. Several researchers have reported that in vivo MR imaging can explore the temporal and spatial migration of magnetically labeled EPCs homing to the tumor and involving in tumor angiogenesis. In the present study, magnetically labeled EPCs were tuansfused into hepatic artery or port vein of PVTT rabbit. MR imaging was performed to follow up MR signal changes of PVTT due to magnetically labeled EPCs. We postulate that in vivo MR imaging of EPCs may be a potential new technique to explore the feeding blood of PVTT and evaluate the interventional treatment of rabbit portal vein tumor thrombus via hepatic artery and portal vein..Purpose:.The purpose of the present study is to investigate the feeding blood and interventional treatment of PVTT using MR cellular imaging..Methods:.EPCs are collected by in vitro culture of rabbit peripheral blood derived mononuclear cells (MNCs). Co-incubation method is employed for EPCs labeling in vitro using Fe2O3-poly-L-lysine (Fe2O3-PLL)..The catheter is put into the portal vein after opening the abdominal of rabbit. The portography is carried out then. VX2 tumor is cut into particles. The particles of VX2 tumor are injected into the rabbit portal vein to establish PVTT model. .Magnetically labeled EPCs is tuansfused into PVTT rabbit via hepatic artery, port vein and ear vein. In vivo serial MR imaging is performed to follow-up the PVTT at different time points after transfusion of EPCs. Tumor angiogenesis and the feeding blood of PVTT is analyzed based on MR signal changes due to magnetically labeled EPCs and Histopathology. .Anticancer drugs are perfused into hepatic artery or port vein of PVTT rabbit. After the perfusion, magnetically labeled EPCs is tuansfused into PVTT rabbit via hepatic artery or port vein. In vivo serial MR imaging is performed to follow-up the PVTT at different time points after transfusion of EPCs. The treatment efficacy is evaluated by the analysis of MR signal changes due to magnetically labeled EPCs.

一般认为门静脉癌栓（PVTT）由肝动脉和门静脉共同供血，但该理论缺乏足够的科学实验数据。本实验用MR细胞成像来活体半定量评价兔PVTT的血供方式和介入疗效。（1）兔外周血分离培养内皮祖细胞（EPCs），超顺磁性氧化铁纳米粒子体外标记EPCs。（2）将VX2瘤块注入兔门静脉建立PVTT模型。（3）将标记的EPCs经肝动脉、门静脉、耳缘静脉途径输注入PVTT兔血管内，MRI活体检测PVTT的信号改变，与病理相对照，分析血管生成状况。比较不同途径输注EPCs后PVTT信号，探讨PVTT的血供方式。（4）将抗肿瘤药物经肝动脉和、或门静脉注入治疗兔PVTT，再经相同途径注入磁性标记的EPCs，MRI活体检测PVTT的信号，比较治疗组和对照组PVTT信号，评价治疗疗效。预期结果：MR细胞成像能活体半定量分析PVTT的血供方式，并评价其治疗疗效。从而为PVTT的血供方式提供理论依据和活体实验数据。

门静脉癌栓（PVTT）是由肝动脉供血，还是由门静脉供血？这是PVTT生物学的基本问题，是临床介入治疗的理论基础。本研究用磁共振细胞成像活体评价兔PVTT的肝动脉和门静脉血供方式及其介入治疗，为临床提供理论依据。.建立PVTT动物模型。将VX2瘤粒（0.1- 0.2 cm）或瘤条（0.1 cm×1.5-2.0 cm）注入兔门静脉，建立门静脉主干或分支、伴有或不伴有弥漫性肝脏转移的PVTT 模型，不同的PVTT模型可用于不同的实验研究目的。.建立经兔耳动脉入路行肝动脉造影的方法。经兔耳中央动脉置入微导管，行肝动脉造影。与经股动脉途径相比，经耳动脉操作时间短、创伤小、且不会留下肢体残疾，能满足一般介入诊疗实验要求。.磁共振细胞成像活体评价兔PVTT的血供方式。PVTT兔4组， A、B、C组分别从肝动脉、门静脉和耳缘静脉注入磁性标记的单个核细胞，D组注入生理盐水。1天后活体磁共振观察PVTT的T2WI信号。A组和B组的信号明显低于C组和D组，（group A vs. group C, U = 4.000, p= 0.025; group A vs. group D, U = 2.000, p= 0.010; group B vs. group C, U = 4.000, p= 0.025; U = 1.000, group B vs. group D, p= 0.006）。A组和B组之间的信号无明显差异。研究数据表明，门静脉和肝动脉都是兔种植性门静脉癌栓的血供来源，此结果有助于对PVTT血供方式的理解，也为临床行肝动脉、门静脉化疗治疗PVTT提供了理论依据。.磁性纳米热疗微球栓塞治疗兔VX2肝癌、PVTT。兔VX2肝癌3组，分别经肝动脉注入微球并行热疗、仅注入微球、仅注入碘油行栓塞治疗。CT随访观察肿瘤的大小。热疗微球栓塞组兔VX2肝癌体积平均缩小了23%，微球栓塞组和碘油栓塞组肿瘤体积分别增长了11％和36％。磁介导热疗微球经肝动脉栓塞治疗对兔VX2肝癌有较好的疗效。PVTT兔随机分为三组，将磁性纳米微球分别经兔肝动脉（A组）、门静脉（B组）注入到兔肝癌PVTT内，1天后磁共振观察肝癌门静脉癌栓的大小、信号。与对照组（C组）相比，经肝动脉和门静脉注入磁性纳米微球，磁共振成像可以活体观察到肝癌PVTT信号明显降低。经肝动脉和门静脉输注微球可以用作兔肝癌PVTT的治疗。