title: XRCC2 as a predictive biomarker for radioresistance in locally advanced rectal cancer patients undergoing preoperative radiotherapy.
abstract: XRCC2 has been shown to increase the radioresistance of some cancers. Here, XRCC2 expression was investigated as a predictor of preoperative radiotherapy (PRT) treatment response in locally advanced rectal cancer (LARC). XRCC2 was found to be overexpressed in rectal cancer tissues resected from patients who underwent surgery without PRT. In addition, overall survival for LARC patients was improved in XRCC2-negative patients compared with XRCC2-positive patients after treatment with PRT (P < 0.001). XRCC2 expression was also associated with an increase in LARC radioresistance. Conversely, XRCC2-deficient cancer cells were more sensitive to irradiation in vitro, and a higher proportion of these cells underwent cell death induced by G2/M phase arrest and apoptosis. When XRCC2 was knocked down, the repair of DNA double-strand breaks caused by irradiation was impaired. Therefore, XRCC2 may increases LARC radioresistance by repairing DNA double-strand breaks and preventing cancer cell apoptosis. Moreover, the present data suggest that XRCC2 is a useful predictive biomarker of PRT treatment response in LARC patients. Thus, inhibition of XRCC2 expression or activity represents a potential therapeutic strategy for improving PRT response in LARC patients.
authors: Department of Gastrointestinal and Pancreatic Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.|Department of Gastrointestinal Surgery, Huaihe Hospital of Hennan University, Kaifeng, China.
authors: Chang-Jiang
authors: CJ
authors: Qin
authors: Department of Gastrointestinal and Pancreatic Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors: Xin-Ming
authors: XM
authors: Song
authors: Department of Gastrointestinal and Pancreatic Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors: Zhi-Hui
authors: ZH
authors: Chen
authors: Department of Gastrointestinal Surgery, Huaihe Hospital of Hennan University, Kaifeng, China.
authors: Xue-Qun
authors: XQ
authors: Ren
authors: Department of Gastrointestinal and Pancreatic Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors: Kai-Wu
authors: KW
authors: Xu
authors: Department of Pathology, Huaihe Hospital of Hennan University, Kaifeng, China.
authors: Hong
authors: H
authors: Jing
authors: Department of Gastrointestinal and Pancreatic Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
authors: Yu-Long
authors: YL
authors: He
mesh_terms: D017209:Apoptosis / Q000528:radiation effects; D016923:Cell Death / Q000528:radiation effects; D045744:Cell Line, Tumor; D053903:DNA Breaks, Double-Stranded; D004260:DNA Repair; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D059565:G2 Phase Cell Cycle Checkpoints / Q000528:radiation effects; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D034622:RNA Interference; D011836:Radiation Tolerance; D018714:Radiotherapy, Adjuvant; D012004:Rectal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D013997:Time Factors; D014162:Transfection; D016896:Treatment Outcome
chemical_list: D004268:DNA-Binding Proteins; C113187:XRCC2 protein, human
keywords: Clinical Section; XRCC2; preoperative radiotherapy; radioresistance; rectal cancer