Azam Ahmadi1, Mohammad Reza Bayatiani2, Fatemeh Seif2, Jamshid Ansari2, Parisa Rashidi2, Mona Moghadasi3, Mobarakeh Etemadi3. 1. Infectious Diseases Research Center (IDRC), Arak University of Medical Sciences, Arak, Iran. 2. Department of Medical Physics and Radiotherapy, Arak University of Medical Sciences and Khansari Hospital, Arak, Iran. 3. Students Research Committee, Arak University of Medical Sciences, Arak, Iran.
Abstract
Background: Current cancer treatments include surgery, radiotherapy, chemotherapy, and immunotherapy. Despite these treatments, a main issue in cancer treatment is early detection. microRNAs (miRNAs) can be used as markers to diagnose and treat cancers. This study investigated the effect of radiotherapy on miR-374 expression, and APC and GSK-3β, two of its target genes, in the WNT pathway, in peripheral blood samples from radiotherapy-treated colorectal cancer (CRC) patients. Methods: Peripheral blood was collected from 25 patients before and after radiotherapy. RNA was extracted from the blood and cDNA synthesized. miR-374, APC, and GSK-3β expression was determined by real-time polymerase chain reaction (RT-PCR) and the amplicons were sequenced. Finally, the data were statistically evaluated. Results: Quantitative RT-PCR revealed significant down-regulation of miR-374 (0.63-fold) and up-regulation of APC (1.12-fold) and GSK-3β (1.22-fold) in CRC patients after five weeks of radiotherapy. Sequencing of PCR-produced amplicons confirmed the conservation of mature and precursor sequences encoding miR-374. miR-374 expression changed with time after radiotherapy treatment and related tumor grading. Increased age and tumor grade positively correlated with decreased miR-374 expression. Conclusion: miR-374 expression, and that of its two target genes, APC and GSK-3β, changed after radiotherapy. These genes can likely be used as diagnostic radiotherapy markers in CRC.
Background: Current cancer treatments include surgery, radiotherapy, chemotherapy, and immunotherapy. Despite these treatments, a main issue in cancer treatment is early detection. microRNAs (miRNAs) can be used as markers to diagnose and treat cancers. This study investigated the effect of radiotherapy on miR-374 expression, and APC and GSK-3β, two of its target genes, in the WNT pathway, in peripheral blood samples from radiotherapy-treated colorectal cancer (CRC) patients. Methods: Peripheral blood was collected from 25 patients before and after radiotherapy. RNA was extracted from the blood and cDNA synthesized. miR-374, APC, and GSK-3β expression was determined by real-time polymerase chain reaction (RT-PCR) and the amplicons were sequenced. Finally, the data were statistically evaluated. Results: Quantitative RT-PCR revealed significant down-regulation of miR-374 (0.63-fold) and up-regulation of APC (1.12-fold) and GSK-3β (1.22-fold) in CRC patients after five weeks of radiotherapy. Sequencing of PCR-produced amplicons confirmed the conservation of mature and precursor sequences encoding miR-374. miR-374 expression changed with time after radiotherapy treatment and related tumor grading. Increased age and tumor grade positively correlated with decreased miR-374 expression. Conclusion: miR-374 expression, and that of its two target genes, APC and GSK-3β, changed after radiotherapy. These genes can likely be used as diagnostic radiotherapy markers in CRC.
Authors: Musthafa Chalikandy Peedikayil; Prem Nair; S M Seena; Lakshmi Radhakrishnan; Shine Sadasivan; V A Naryanan; V Balakrishnan Journal: Indian J Gastroenterol Date: 2010-04-28