The Expression Levels of RAD51 after Ionizing Radiation in Peripheral Blood Lymphocytes for Evaluation of DNA Repair in Breast Cancer Patients Referred to Ahvaz Golestan Hospital

Document Type : Original Article


1 Departmant of Medical GeneticAhvaz, Cellular and Molecular Biology Research Center, University of Medical Sciences. Ahvaz, Iran.

2 Departmant of Medical Physics, Ahvaz,University of Medical Sciences, Ahvaz, Iran

3 Department of Radiotherapy & Oncology, Golestan Hospital.

4 Department of Epidemiology& Biostatistics, Diabetes Research Center, School of Health, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.


Background and Objective: Breast cancer is one of the most common cancers among the women. One of the radical method for treatment of breast cancer is radiotherapy. Radiation induces different responses in cells, including cell cycle checkpoint activation, DNA repair and apoptosis. To check cellular responses and radiosensitivity in each patient, DNA repair mechanism and proteins, as biological markers, can be evaluated. Based on the repair capacity and radiosensitivity of cells in each patient we can design a treatment planning using radiation therapy  The purpose of this study was to evaluate to the radiosensitivity in breast cancer patients to improve treatment planning
Subjects and Methods:A  quantitative  reverse  transcriptase
PCR-based assay for measurement of the expression  level  of  RAD51  in lymphocyte cells for all breast cancer patients and healthy controls. Statistical analyses were performed using SPSS17 software. The relation between the expression level of RAD51and clinical characteristics of patients was analyzed by using the nonparametric Mann-Whitney and Kruskal-Wallis tests.
Results:The expression level of RAD51 significantly up regulated in the peripheral blood lymphocytes of patients (P= 0.006, 8 Fold change) compared to healthy controls. A significantcorrelation between the expression level of RAD51 and HER2/neu (P=0.024) as well as patients age (P= 0.03).
Conclusion: Expression level of RAD51 in lymphocyte cells can be a useful biological marker for evaluation of radiosensitivity in breast cancer.


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