BACKGROUND
Resistance to the potent growth inhibitory effects of TGF- (transforming growth factor-) is a characteristic of many malignancies. TGF- insensitivity has been attributed to alterations in the number and function of the TGF- receptors as well as disturbances of downstream signal transduction. The aim of this study was to examine the expression of TGF-1 and its receptors in human colorectal cancer tissue and determine its relationship with cancer growth and with prognostic factors.
METHODS
Immunohistochemical staining of TGF-1, TGF-RI, and TGF-RII was performed on 20 human colorectal adenomas, 30 carcinomas and 10 normal mucosas as a control.
RESULTS
The staining indices of TGF-1, TGF-RI, and TGF-RII increased in adenomas and carcinomas compared with normal mucosas and adenomas, respectively. In adenomas the staining index of TGF-1 significantly increased with the severity of atypism. The staining index of TGF-RII increased in the carcinomas in the right colon and rectum, compared with those in the left colon.
CONCLUSION
The enhanced expression of TGF-1, TGF-RI and II in the colorectal carcinoma suggests an important role of colorectal carcinogenesis and tumor progression.