Comparative Expression of Breast Cancer 1 Tumor Suppressor Protein in Cancerous and Healthy Colorectal Specimens

Document Type : Original Article (s)


1 Associate Professor, Department of Anatomical Sciences, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran

2 Student of Medicine, School of Medicine AND Student Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran


Background: Various tumor suppressor genes play a role in colorectal cancer; the role of breast cancer 1 (BRCA1) tumor suppressor gene is of the most importance among them. The biological performance of breast cancer 1 (BRCA1) in cancer has been recognized and its prognostic significance has been verified in colorectal cancer; decrease in the expression of this protein in cancer indicates a poor prognosis for patients. The aim of the current study was to evaluate BRCA1 protein expression in cancerous colorectal specimens compared to healthy tissue surrounding the tumor using immunohistochemistry method.Methods: A total of 50 cancerous colorectal and 50 healthy specimens were collected. The expression of BRCA1 protein was evaluated upon paraffin sections through immunohistochemistry method.Findings: The findings of the current study showed that the level of BRCA1 protein expression significantly decreased in cancerous specimens compared to healthy tissue surrounding the tumor (P = 0.026).Conclusion: The expression of BRCA1 could be used as an appropriate biological marker in the diagnosis and prognosis of colorectal cancer.


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