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

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.

Upregulation of Transforming Growth Factor-beta Receptors in the Rat Remnant Kidney / 대한신장학회잡지

TGF-beta1 plays a major role in the regulation of extracellular matrix synthesis and degradation. TGF-beta1 exerts its biological effects by interacting with specific cell surface receptors including type I and II receptors(TGFbetaRI and RII). The purpose of this study is to investigate the expression of TGFbetaRI and RII proteins in the kidney during the development of glomerulosclerosis and renal fibrosis in rats with subtotal nephrectomy. Forty male Sprague-Dawley rats weighing 200 to 220 grams were divided into two groups: 25 rats were subjected to 5/6 renal ablation and 15 to sham operation. The animals were sacrificed 1, 2, 4, 8, and 16 weeks following operation and the kidneys were removed for histological and immunohistochemical studies for TGF-beta1, TGFbetaRI, and TGFbetaRII. The results showed increased glomerulosclerosis, interstitial fibrosis, and mononuclear cellular infiltration with time and progressively higher immunohistochemical TGF-beta1, TGFbetaRI, and TGFbetaRII staining in rats with subtotal nephrectomy. We conclude that increase in TGFbetaRI and RII expression in remnant kidney rats may be causally related with the development of renal fibrosis.