Résumé
Type IV collagenases are thought to play a role in the proteolysis of the basement membrane and the extracellular matrix by the malignant cells that occur early in the development of invasive tumors. In several human tumors, including breast, colonic, ovarian, and hepatocellular carcinomas, type IV collagenase expression has been positively correlated with tumor invasiveness. In this study, we examined the expression and the activation of 72 kDa type IV collagenase in cancerous and normal tissues of the colon and, we attempted to clarify its clinical significance in 45 cases of human colorectal cancer by using northern blot analysis and gelatin zymography.This study showed that the level of 72 kDa type IV collagenase mRNA was increased in colorectal cancer and that this increase was associated with increased enzymatic activity. While there was a difference in the expression and the activation of this enzyme between T2 and T3, this enzyme activity did not show a definite correlation with cancer progress as measured by the depth of tumor invasion and lymph node metastasis.
Sujets)
Humains , Membrane basale , Technique de Northern , Région mammaire , Carcinome hépatocellulaire , Collagenases , Côlon , Tumeurs colorectales , Matrice extracellulaire , Gélatine , Noeuds lymphatiques , Matrix metalloproteinase 2 , Métastase tumorale , Protéolyse , ARN messagerRésumé
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