en زیست شناسی سلولی Cell Biology مقالات اصلی Original Article <div style="text-align: justify;"><strong><em>Background:</em></strong> Current cancer treatments include surgery, radiotherapy, chemotherapy, and immunotherapy.&nbsp;Despite these treatments, a main issue in cancer treatment is early detection. microRNAs (miRNAs) can be&nbsp;used as markers to diagnose and treat cancers. This study investigated the effect of radiotherapy on miR-374&nbsp;expression, and APC and GSK-3&beta;, two of its target genes, in the WNT pathway, in peripheral blood samples&nbsp;from radiotherapy-treated colorectal cancer (CRC) patients.<br> <br> <strong><em>Methods:</em></strong> Peripheral blood was collected from 25 patients before and after radiotherapy. RNA was&nbsp;extracted from the blood and cDNA synthesized. miR-374, APC, and GSK-3&beta; expression was determined&nbsp;by real-time polymerase chain reaction (RT-PCR) and the amplicons were sequenced. Finally, the data were&nbsp;statistically evaluated.<br> <br> <strong><em>Results:</em></strong> Quantitative RT-PCR revealed significant down-regulation of miR-374 (0.63-fold) and upregulation&nbsp;of APC (1.12-fold) and GSK-3&beta; (1.22-fold) in CRC patients after five weeks of radiotherapy.&nbsp;Sequencing of PCR-produced amplicons confirmed the conservation of mature and precursor sequences<br> encoding miR-374. miR-374 expression changed with time after radiotherapy treatment and related tumor&nbsp;grading. Increased age and tumor grade positively correlated with decreased miR-374 expression.<br> <br> <strong><em>Conclusions:</em></strong> miR-374 expression, and that of its two target genes, APC and GSK-3&beta;, changed after&nbsp;radiotherapy. These genes can likely be used as&nbsp; diagnostic radiotherapy markers in CRC.</div> Biomarker, Colorectal cancer, Mir-374, Radiotherapy. 614 621 http://rbmb.net/browse.php?a_code=A-10-555-2&slc_lang=en&sid=1 Azam Ahmadi 100319475328460012449 100319475328460012449 No Infectious Diseases Research Center (IDRC), Arak University of Medical Sciences, Arak, Iran. Mohamd Reza Bayatiani 100319475328460012450 100319475328460012450 No Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran. Fatemeh Seif ahar_s59@yahoo.com. 100319475328460012451 100319475328460012451 Yes Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran. Jamshid Ansari 100319475328460012452 100319475328460012452 No Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran. Parisa Rashidi 100319475328460012453 100319475328460012453 No Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran. Mona Moghadasi 100319475328460012454 100319475328460012454 No Students Research Committee, Arak University of Medical Sciences, Arak, Iran. Mobarakeh Etemadi 100319475328460012455 100319475328460012455 No Students Research Committee, Arak University of Medical Sciences, Arak, Iran.