原位注射法建立人胰腺癌SW1990裸鼠种植瘤模型及高频内镜超声探头对其的监测

Establish of the orthotopic human pancreatic cancer model in mice and high frequency probe of endoscopy ultrasonographic monitoring

目的建立裸小鼠人胰腺癌原位种植瘤模型，探索监测种植瘤生长的方法。方法将对数生长期的人胰腺癌细胞株SW1990制备成细胞悬液，原位注射于Balb／c—nu裸小鼠胰腺尾部包膜下，利用高频内镜超声（EUS）探头体表观察肿瘤结节的生长及声像图像。结果20只裸小鼠均接种成功，1只裸鼠于接种后25d时死亡。接种后14d，EUS检查的瘤体大小为（8．09±2．61）mm^3，肿瘤结节呈均质低回声，边界清楚，周边有包膜及声晕，形态规则，30％的肿瘤结节周边可见低速环绕彩色血流信号；接种后28d，瘤体增大至（12．40±3．51）mm^3，70％的肿瘤结节呈不规则形，部分为分叶状，肿块呈低回声，不均质，未见液化坏死区，70％的肿瘤结节周边可见低速环绕彩色血流信号。结论原位注射法是建立裸小鼠人胰腺癌原位种植瘤模型较理想的方法，操作简便，成瘤率高；高频内镜超声显像是可靠的监测胰腺原位种植瘤的手段。

Objective To establish the orthotopic human pancreatic cancer model in mice and study the method to detect the tumor growth. Methods Human pancreatic cancer cell lines SW1990 in logarithmic phase was made into cell suspension and in sitn injected into the envelope of pancreatic tail of BALB/c nude mice. High-frequency endoscopy ultrasound was used to observe the growth of tumor mass and its imaging characteristics were studied. Results 20 nude mice were successfully implanted, and 1 died 25 h after implantation. 14 days after implantation, the tumor of pancreatic cancer on EUS was （8.09 ± 2.61 ） mm^3 , the tumor appeared as homogeneous hypoechoic mass with clear boundary, and envelope as well as sound halo was present, and the shape was regular; there was low speed circular vasculature signal in around 30% of tumor. The tumor size increased to （12.40 ± 3.51 ）mm^3, and the shape of 70% tumor was irregular, and some appeared as lobulated, and the tumor appeared as heterogeneous hypoeehoic mass, no necrosis or liquefaction was found 28 days after implantation. There was low speed circular vasculature signal in around 70% tumors. Conclusions The orthotopic pancreatic cancer model in nude mouse can be established by in situ injection and this method is relatively ideal because it is simple and effective. The high frequency probe of endoscopic uhrasonograph is a reliable method for monitoring implanted pancreatic cancer.