title: DNA ligase4 as a prognostic marker in nasopharyngeal cancer patients treated with radiotherapy.
abstract: BACKGROUND
  The capability for DNA double-strand breaks (DSBs) repair is crucial for inherent radiosensitivity of tumor and normal cells. We have investigated the clinicopathologic significance of DNA repair gene expression in nasopharyngeal (NP) carcinoma.
  
  
  METHODS
  A total of 65 NP cancer patients who received radiotherapy were included. The immunopositivity to Ku 70, DNA-PKcs, MRN, RAD50, XRCC4, and LIG4 were examined in all tumor tissues.
  
  
  RESULTS
  The patients comprised 42 males and 23 females, with a median age of 56 years (range, 18-84). The expression levels of RAD50 (0,+1,+2,+3) were 27.7%, 32.3%, 21.5%, and 18.5%. LIG4 (±) were 43.1% and 56.9% respectively. The 5-year OS rate of patients with LIG4 (±) were 90% and 67.9%, respectively (p=0.035). The 5-year TTP rate of patients with LIG4 (±) were 75.9%, 55.5%, respectively (P=0.039).
  
  
  CONCLUSIONS
  Our results suggest the possibility of predicting the radiosensitivity of NP cancer by performing immunohistochemical analysis of LIG4.
authors.affiliation: Department of Internal Medicine, Dong-A University College of Medicine, Busan, Korea E-mail : drosy@dau.ac.kr.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Kim
authors.forename: Sung Yong
authors.initials: SY
authors.lastname: Oh
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Kim
authors.forename: Seul
authors.initials: S
authors.lastname: Lee
authors.forename: Myeong Seok
authors.initials: MS
authors.lastname: Koh
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Suee
authors.initials: S
authors.lastname: Lee
authors.forename: Sung-Hyun
authors.initials: SH
authors.lastname: Kim
authors.forename: Heon Soo
authors.initials: HS
authors.lastname: Park
authors.forename: Won Joo
authors.initials: WJ
authors.lastname: Hur
authors.forename: Jin Sook
authors.initials: JS
authors.lastname: Jeong
authors.forename: Mi Ha
authors.initials: MH
authors.lastname: Ju
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Seol
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Choi
authors.forename: Joo Seop
authors.initials: JS
authors.lastname: Chung
authors.forename: Hyo-Jin
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D014408:Biomarkers, Tumor / Q000378:metabolism*; D002277:Carcinoma; D002294:Carcinoma, Squamous Cell / Q000201:enzymology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D059248:Chemoradiotherapy; D000072481:DNA Ligase ATP; D011088:DNA Ligases / Q000378:metabolism*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000201:enzymology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D009364:Neoplasm Recurrence, Local / Q000201:enzymology* / Q000401:mortality / Q000473:pathology / Q000628:therapy; D009367:Neoplasm Staging; D011379:Prognosis; D011836:Radiation Tolerance; D015996:Survival Rate; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C000607893:LIG4 protein, human; D011088:DNA Ligases; D000072481:DNA Ligase ATP