Expression of TGF-beta1, TGF-beta Receptor Type II and VEGF in Colorectal Adenomas and Adenocarcinomas / 대한소화기내시경학회지

ABSTRACT

BACKGROUND/AIMS: The aim of study was to investigate the expression of TGF-beta, TGF-RII and VEGF determined by immunohistochemical analysis with a comparison of the clinicopathological parameters such as tumor size, grade of dysplasia, lymph node metastasis and Dukes' stage in colorectal adenomas and adenocarcinomas, by use of a tissue microarray method. METHODS: The expression of TGF-beta1, TGF-betaRII, and VEGF was determined by immunohistochemistry in 20 adenomas and 40 adenocarcinomas. Tissue microarrays consisting of 2 mm cores from corresponding blocks were constructed and stained. RESULTS: In adenomas, the staining intensity of TGF-beta, TGF-betaRII and VEGF was increased in a high-grade dysplasia group of patients as compared a with low-grade dysplasia group of patients, respectively. The staining intensity of TGF-betaRII was significantly increased in a high-grade dysplasia group of patients than a low-grade dysplasia group of patients (p =0.021). For the adenocarcinomas, the expression and staining intensity of TGF-beta1, TGF-betaRII and VEGF were increased as compared with the adenomas (p<0.001). However, no significant correlation was observed between the staining intensity of TGF-beta, TGF-betaRII and VEGF and the clinicopathological parameters. CONCLUSIONS: The increased expression of TGF-beta1, TGF-betaRII and VEGF in colorectal adenocarcinoma suggests a role for these proteins in colorectal carcinogenesis. Loss of the growth-inhibitory effect of TGF-beta may commence in the early stage of colorectal carcinogenesis.