人胃癌裸鼠原位移植模型的生物学行为研究

目的建立人胃癌裸鼠胃壁原位移植瘤模型，并与相应的皮下移植瘤作比较，以探讨宿主器官微环境对胃癌细胞浸润及转移等生物学行为的影响．方法将人胃癌细胞系ＭＧｃ８０３及其克隆株Ｃ１１癌细胞分别接种于裸鼠胃壁及背部皮下，比较原位和皮下移植瘤的成瘤率、生长率、生长方式及浸润、转移等生物学行为，以及体外回复培养后瘤细胞的增殖能力．结果胃壁原位及皮下移植瘤体内成瘤率、生长率及形态学上均无明显不同；其体外增殖能力也无显著性差异．但皮下移植瘤多呈局限性生长，无肝、脾、肾转移，其转移仅限于肺及个别局部淋巴结．胃壁原位移植瘤则浸润破坏胃壁各层组织结构，并直接蔓延到邻近各器官组织．其转移既有经血道至肝、肺、脾、肾等部位，也有经淋巴道至多数局部及远处淋巴结，其淋巴结的转移率较皮下移植瘤有显著增高（Ｐ＜００５）；且多伴有腹、盆腔内广泛种植性转移．结论裸鼠胃壁微环境较皮下组织更适合于人胃癌ＭＧｃ８０３及Ｃ１１移植瘤的浸润及转移的表达，该原位移植瘤模型的恶性生物学行为更接近临床胃癌患者的体内侵袭及转移的实际．

Biological behavior of orthotopic implantation model of human gastric carcinoma in nude mice

AIM To establish an orthotopic model of human gastric carcinoma in the stomach wall of nude mice, and compare with its ectopic implantation counterpart in the subcutaneous tissues in oder to investigate whether the microenvironment of the host organ influenced the biological behavior such as invasion and metastasis of the carcinoma cells. METHODS The human gastric carcinoma cell line MGc 803 and its clonal line C11 were inoculated into the stomach wall and the subcutaneous tissues of nude mice respectively. The tumor formation rate, the growth rate, the mode of growth, the invasion and metastatic behavior of the orthotopic and ectopic xenografts were investigated and compared. The specimens from the xenografts was cultured in vitro , and the cell proliferation ability was determined. RESULTS No significant differences were found between the orthotopic and ectopic xenografts in vitro and their cultured cells in vitro with respect to tumor formation rate, growth rate, morphologic characteristics, and the proliferation ability. However, tumor grew in subcutaneous tissue in lungs and few local lymph nodes. In contrast, tumors in the stomach wall invaded and destroyed the normal structure of the stomach wall, also infiltrated to the nearby organs. They metastasized to different organs, the lungs, the liver, spleen, and kidney. The lymph node (local and distant) metastasis incidence of the orthotopic xenografts was obviously frequent ( P <0 05) versus that of ectopic tumors, and the metastatic tumors could spread through the peritoneal and pelvic cavity. CONCLUSION The stomach wall of nude mice provided a more suitable microenvironment for the human gastric carcinoma MGc 803 and C11 xenografts to express their invasion and metastasis. The malignant biologic behavior of this orthotopic implantation model is similar to the metastasis of the gastric carcinoma in clinical patients.