Influence of XRCC4 expression in esophageal cancer cells  on the response to radiotherapy

We examined 92 patients with esophageal squamous cell carcinoma (ECSS) who were treated by radiotherapy between 1999 and 2008. Immunohistochemical examination of tumor tissue for Ki-67 and DSB-related proteins, including XRCC4, Ku86, and DNA-PKcs, was performed using pretreatment biopsy specimens. Low expression of XRCC4 was detected in 31 of 92 examined samples (33.7  %). The 5-year overall survival (OS) rate was 67.7 % in the low expression group and 31.0 % in the high expression group ( < em class= " a-plus-plus " > P < /em >  = 0.00). Multivariate analysis confirmed that advanced T-stage (HR 3.24, < em class= " a-plus-plus " > P < /em >  = 0.01), radiation dose less than 66 Gy (HR 2.23, < em class= " a-plus-plus " > P < /em >  = 0.02), absence of systemic chemotherapy (HR 2.59, < em class= " a-plus-plus " > P < /em >  = 0.05), and high expression of XRCC4 (HR 12.0, < em class= " a-plus-plus " > P < /em >  = 0.02) were independent prognostic factors for predicting poor OS. Other DSB-related proteins and Ki-67 were not predictive factors. XRCC4 expression might have an influence on results of radiotherapy for patients with ESCC. < /p >
Source: Medical Molecular Morphology - Category: Molecular Biology Source Type: research