Razi Journal of Medical Sciences

Background: Colorectal cancer is the fourth most common cancer in the world. It is the third largest risk factor for cancer individuals. The number of new cases is rising since 1975. Hyper activities of EGFR family have been reported in various cancers. The purpose of this study was to investigate the expression levels of HER2 in colorectal cancer and its possible association with advanced stages of disease.

Methods: In this study 20 samples of colorectal cancer paraffin block and 10 non-tumor individual samples were collected. After de-paraffin, RNA molecules were extracted from samples by RNX plus solution, after that CDNA was synthetized by reverse transcription method and finally the relative HER2 gene expression was evaluated by Real Time PCR.

Results: In 20 cases of colorectal cancer compared with non-tumor samples, over expression of HER2 gene was observed. The increased expression compared with non-tumor samples observed in all patient samples and the amount of over expressed HER2 in patients with stage III was more than stage II and I. expression levels were also increased by increasing the age. The observation showed that the increased expression of HER2 occurs from the early stages of the disease.

Conclusion: Due to the increased HER2 expression in colorectal cancer, it is clear that the HER2 assessment can be considered as a valuable prognostic factor for screening especially in early stages of disease.