TIMP-2基因转染在裸鼠胃癌中Ⅳ型胶原酶及Ⅳ型胶原改变的研究

STUDY ON TYPE Ⅳ COLLAGENASE AND TYPE Ⅳ COLLAGEN IN GASTRIC CARCINOMA OF NUDE MICE TRANSFECTED WITH TIMP 2 GENE

目的：探讨金属蛋白酶抑制剂（ＴＩＭＰ－２）基因体外转染胃癌ＳＧＧ－７９０１细胞系后建立的裸鼠侵袭模型中的Ⅳ型胶原和Ⅳ型胶原酶改变的情况。方法：用ＴＩＭＰ－２基因体外转染的胃癌ＳＧＧ－７９０１细胞系建立裸鼠肿瘤侵袭模型，并应用免疫组化对侵袭部位的组织Ⅳ型胶原和Ⅳ型胶原酶前体（ＭＴ－ＭＭＰ）的改变作了研究。结果：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％，两者有显著性差异（Ｐ＜０．０１）。Ⅳ型胶原染色显示，肾小管及肾小球基底膜完整呈连续性线状分布，而肿瘤部位的Ⅳ型胶原在基底膜处出现断裂和缺失，肿瘤浸润部见Ⅳ型胶原酶表达异常丰富。结论：组织金属蛋白酶抑制剂ＴＩＭＰ－２基因转染参与肿瘤细胞分泌胶原酶的调控过程，抑制了Ⅳ型胶原的降解，是肿瘤侵袭。

OBJECTIVE To explore the change in type Ⅳ collagen and matrix metalloproteinase (MT-MMP) in nude mice transfected with TIMP 2 gene.METHODS An invasive model of gastric carcinoma in nude mice was re constructed with gastric carcinoma cell SGC 7901 and SGC 7901 T2.The expression of type Ⅳ collagenase(MT MMP) and the changes in basement membrane (BM) in normal kidney tissue and malignant lesion of gastric were studied by immunohistochemical technique.RESULTS The results showed that the positive rate of type Ⅳ collagenase (MT MMP) was 36 6% in normal kindey tissue and 70% in malignant lesions ( P <0 05).The intact patterns of BM were observed in the normal group, while the disruptive and fragmentary patterns were seen in the neoplasns、.CONCLUSIONS The inhibitor of matrix metalloproteninase 2 gene inhibiting degradation of MT MMP,may play an important role in invasion and metastasis of gastric carcinoma.