Evaluation of the Effect of Radiotherapy on CCL5/miR-214 -3p/MALAT1 Genes Expression in Blood Samples of Breast Cancer Patients

Current cancer therapies include chemotherapy, radiation therapy, immunotherapy, and surgery. Despite these treatment methods, a major point in cancer treatment is early detection. RNAs (mRNA, miRNAs, and LncRNA) can be used as markers to improve cancer diagnosis and treatment. This research examined how radiotherapy affected CCL5, miR-214, and MALAT-1 gene expression in the immune pathway in peripheral blood samples from radiation therapy-treated breast cancer patients. Before and after radiotherapy, peripheral blood was collected from 15 patients in four steps. Blood samples were collected in an outpatient facility from 20 healthy female volunteers with no history of malignant or inflammatory conditions. RNA was extracted from the blood samples and cDNA was synthesized. CCL5, miR-214, and MALAT-1 gene expression were determined by real-time polymerase chain reaction (RT-PCR). CCL5 protein levels in the serum were determined in 80 samples (60 BC and 20 healthy controls) using Quantikine Enzyme-Linked Immunosorbent Assay (ELISA) kits (R&D Systems). The data were then statistically evaluated. There was a significant difference between CCL5 levels in tumoral and adjacent normal blood samples (p < 0.05). The results also show that the level of gene expression and serum concentration of CCL5 protein in different phases of radiotherapy is significantly different. On the other hand, the expression level of the miR-214 gene was significantly decreased in patients compared to the control group, but this decrease was not significant for the MALAT-1 gene (p< 0.05). Also, after each stage of radiotherapy, the expression level of these two genes showed a decrease, but in the fourth week after radiotherapy, this decrease was significant (p< 0.05). Radiotherapy is associated with a decrease in the expression of miR-214 and MALAT-1, as a result, an increase in the expression of CCL5. An increase in the concentration of CCL5 protein is accompanied by an increase in the level of monocytes, which ultimately causes the infiltration of macrophages and can ultimately cause cancer recurrence. It is suggested that these genes can probably be used as diagnostic and therapeutic radiotherapy markers in breast cancer.