Background: Her-2/neu protein is a member of the epidermal growth factor family of receptors which, upon activation, contributes positively to the growth and dissemination of neoplasia. Over-expression of
this protein has been reported in different human tumors and shown to be a valuable prognostic factor especially in breast cancer. A limited number of studies have also shown positive correlation between Her-2/neu over-expression and advanced tumor progression in colorectal cancer. Here we studied the prevalence of Her-2/neu over-expression in Iranian colorectal cancer patients and assessed its correlation with the disease’s progression.
Material/Methods: Fifty-fi ve colorectal cancer patients in different stages of disease were studied. The pathology specimens were immunohistochemically stained using monoclonal antibody against Her-2/neu protein. Correlation of the degree of staining with clinicopathological parameters was investigated.
Results: It was shown that in an Iranian population of colorectal cancer patients, the Her-2/neu oncogene is over-expressed in a signifi cant number of cases and positively correlates with tumor stage and
grade, being more frequent in the advanced and less differentiated samples.
Conclusions: These data can be applied in designating new chemotherapeutic regimens using drugs that block the function of Her-2/neu in colorectal cancer patients in Iran.

Keywords: Colorectal Neoplasms - epidemiology, Iran - epidemiology, Antibodies, Monoclonal - metabolism, Colorectal Neoplasms - pathology, Genes, erbB-2, Iran - epidemiology, Prevalence, Receptor, erbB-2 - metabolism