Wang Yiru, Yao Binwei, Li Hongfei, Zhang Yan, Gao Hanjing, Gao Yabin, Peng Ruiyun, Tang Jie
Department of Ultrasound, Chinese PLA General Hospital, Beijing, China.
Department of Experimental Pathology, Beijing Institute of Radiation Medicine, Beijing, China.
J Ultrasound Med. 2017 May;36(5):955-963. doi: 10.7863/ultra.16.03066. Epub 2017 Mar 4.
To investigate the stiffness of human prostate cancer in a xenograft implantation model using shear wave elastography and compare the pathologic features of tumors with varying elasticity.
Human prostate cancer DU-145 cells were injected into 24 nude male mice. The mice were divided into 3 groups according to the time of transplantation (6, 8, and 10 weeks). The volume, elasticity, and Young modulus of tumors were recorded by 2-dimensional sonography and shear wave elastography. The tumors were collected for pathologic analyses: hematoxylin-eosin staining, Ponceau S, and aniline staining were used to stain collagen and elastic fibers, and picric acid-sirius red staining was used to indicate type I and III collagen. The area ratios of collagen I/III were calculated. The correlation between the Young modulus of the tumor and area ratio of collagen I/III were evaluated. Immunohistochemistry of vimentin and α-smooth muscle actin was performed.
Nineteen tumors in 3 groups were collected. The volume and mean Young modulus increased with the time of transplantation. There were more collagen fibers in the stiff tumors, and there were significant differences in the area ratios of collagen I/III between groups 1 (mean ± SD, 0.50 ± 0.17) and 3 (1.97 ± 0.56; P < .01). The Young modulus of the tumors showed a very significant correlation with the area ratios of collagen I/III (r = 0.968; P < .05). The expression level of α-smooth muscle actin protein was higher in group 3 than in the other groups, but differences in vimentin expression were barely seen.
Shear wave elastography is a novel useful technology for showing the elasticity of human prostate cancer xenograft implantation tumors. Collagen fibers, especially collagen type I, play a crucial role in the elasticity in the human prostate cancer xenograft implantation model.
利用剪切波弹性成像技术研究人前列腺癌异种移植模型中的肿瘤硬度，并比较不同弹性肿瘤的病理特征。
将人前列腺癌DU-145细胞注射到24只雄性裸鼠体内。根据移植时间（6周、8周和10周）将小鼠分为3组。通过二维超声和剪切波弹性成像记录肿瘤的体积、弹性和杨氏模量。收集肿瘤进行病理分析：采用苏木精-伊红染色、丽春红S和苯胺染色对胶原纤维和弹性纤维进行染色，苦味酸-天狼星红染色用于显示I型和III型胶原。计算I/III型胶原的面积比。评估肿瘤杨氏模量与I/III型胶原面积比之间的相关性。进行波形蛋白和α-平滑肌肌动蛋白的免疫组织化学检测。
3组共收集到19个肿瘤。肿瘤体积和平均杨氏模量随移植时间增加。硬度较高的肿瘤中胶原纤维较多，第1组（均值±标准差，0.50±0.17）和第3组（1.97±0.56；P<0.01）之间I/III型胶原面积比存在显著差异。肿瘤杨氏模量与I/III型胶原面积比呈非常显著的相关性（r=0.968；P<0.05）。第3组α-平滑肌肌动蛋白蛋白表达水平高于其他组，但波形蛋白表达差异不明显。
剪切波弹性成像是一种显示人前列腺癌异种移植肿瘤弹性的新型有用技术。胶原纤维，尤其是I型胶原，在人前列腺癌异种移植模型的弹性中起关键作用。
