title: High XRCC1 protein expression is associated with poorer survival in patients with head and neck squamous cell carcinoma.
abstract: OBJECTIVE
  We evaluated X-ray repair complementing defective repair in Chinese hamster cells 1 (XRCC1) protein in head and neck squamous cell carcinoma (HNSCC) patients in association with outcome.
  
  
  METHODS
  XRCC1 protein expression was assessed by immunohistochemical (IHC) staining of pretreatment tissue samples in 138 consecutive HNSCC patients treated with surgery (n = 31), radiation (15), surgery and radiation (23), surgery and adjuvant chemoradiation (17), primary chemoradiation (51), and palliative measures (1).
  
  
  RESULTS
  Patients with high XRCC1 expression by IHC (n = 77) compared with patients with low XRCC1 expression (n = 60) had poorer median overall survival (OS; 41.0 months vs. OS not reached, P = 0.009) and poorer progression-free survival (28.0 months vs. 73.0 months, P = 0.031). This association was primarily due to patients who received chemoradiation (median OS of high- and low-XRCC1 expression patients, 35.5 months and not reached respectively, HR 3.48; 95% CI: 1.44-8.38; P = 0.006). In patients treated with nonchemoradiation modalities, there was no survival difference by XRCC1 expression. In multivariable analysis, high XRCC1 expression and p16(INK4a)-positive status were independently associated with survival in the overall study population (HR = 2.62; 95% CI: 1.52-4.52; P < 0.001 and HR = 0.21; 95% CI: 0.06-0.71; P = 0.012, respectively) and among chemoradiation patients (HR = 6.02; 95% CI: 2.36-15.37; P < 0.001 and HR = 0.26; 95% CI: 0.08-0.92, respectively; P = 0.037).
  
  
  CONCLUSIONS
  In HNSCC, high XRCC1 protein expression is associated with poorer survival, particularly in patients receiving chemoradiation. Future validation of these findings may enable identification of HNSCC expressing patients who benefit from chemoradiation treatment.
authors: UNC Lineberger Comprehensive Cancer Center; Department of Biostatistics, UNC School of Medicine, Chapel Hill, North Carolina, USA.
authors: Mei-Kim
authors: MK
authors: Ang
authors: Mihir R
authors: MR
authors: Patel
authors: Xiao-Ying
authors: XY
authors: Yin
authors: Sneha
authors: S
authors: Sundaram
authors: Karen
authors: K
authors: Fritchie
authors: Ni
authors: N
authors: Zhao
authors: Yufeng
authors: Y
authors: Liu
authors: Alex J
authors: AJ
authors: Freemerman
authors: Matthew D
authors: MD
authors: Wilkerson
authors: Vonn
authors: V
authors: Walter
authors: Mark C
authors: MC
authors: Weissler
authors: William W
authors: WW
authors: Shockley
authors: Marion E
authors: ME
authors: Couch
authors: Adam M
authors: AM
authors: Zanation
authors: Trevor
authors: T
authors: Hackman
authors: Bhishamjit S
authors: BS
authors: Chera
authors: Stephen L
authors: SL
authors: Harris
authors: C Ryan
authors: CR
authors: Miller
authors: Leigh B
authors: LB
authors: Thorne
authors: Michele C
authors: MC
authors: Hayward
authors: William K
authors: WK
authors: Funkhouser
authors: Andrew F
authors: AF
authors: Olshan
authors: Carol G
authors: CG
authors: Shores
authors: Liza
authors: L
authors: Makowski
authors: D Neil
authors: DN
authors: Hayes
mesh_terms: D000818:Animals; D016466:CHO Cells; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000401:mortality*; D045744:Cell Line, Tumor; D059248:Chemoradiotherapy; D006224:Cricetinae; D003412:Cricetulus; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D005260:Female; D055786:Gene Knockout Techniques; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D000077195:Squamous Cell Carcinoma of Head and Neck; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D019941:Cyclin-Dependent Kinase Inhibitor p16; D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human