用金属蛋白酶抑制剂——TIMP-2基因体外转染的胃癌SGC-7901细胞系建立裸鼠肾包膜下种植的侵袭模型,并应用免疫组化对侵袭部位的组织Ⅳ型胶原酶前体——MT-MMP的表达及基底膜的改变作了研究.结果显示,正常肾脏组织Ⅳ型胶原酶反应阳性率为39.64%,在种植肿瘤中阳性率为69.14%,两者差异显著(P<0.01),Ⅳ型胶原染色显示,肾小管及肾小球基底膜完整,而肿瘤中基底膜出现断裂或缺失,在肿瘤浸润部见Ⅳ型胶原酶表达异常丰富,而Ⅳ型胶原缺如.表明Ⅳ型胶原酶对基底膜的破坏是胃癌浸润转移的重要机制.

The invasive model of gastric carcinoma in nude mice was constructed with gastric carcinoma cells SGC-7901 and SGC-7901-T2. The expression of type IVcollagenase (MT-MMP) and the changes of basement membrane (BM) in normal kidey tissue and malignant lesion of gastric were studied by immunohistochemical technique. The results showed that the positive rate of type IV collagenase(MT-MMP)was 36.6%in normal kidey tissue and 70% in malignant lesions (P < 0.05). The intact patterns of BM were observed in normal groups while the disruptive and fragmentary patterns in malignants. The results suggest that the tissue inhibitor of matrix metalloproteinase-2 gene plays an important role in the destruction of BM and the invasion and metastasis of gastric carcinoma.