title: Prognostic role of sensitive-to-apoptosis gene expression in rectal cancer.
abstract: OBJECTIVE
  To investigate the association between prognosis of rectal cancer treated with chemoradiotherapy (CRT) and expression of sensitive-to-apoptosis (SAG), B-cell lymphoma-extra large (Bcl-X(L)) and Bcl-2 homologous antagonist/killer (Bak).
  
  
  METHODS
  Real-time quantitative polymerase chain reaction was used to determine the expression of proteins of interest, namely SAG, Bcl-X(L), Bak and β-actin, in rectal carcinoma patients who had a follow-up period of 3 years after CRT. Biopsy specimens were excised from the rectal tumor preceding CRT.
  
  
  RESULTS
  SAG, Bcl-X(L) and Bak proteins showed significant correlations with each other. In multivariate analysis, patients with high vs low SAG expression showed a statistically significant difference in 2-year survival rates: 56% vs 73%, respectively (P = 0.056). On the other hand, there were no significant correlations between the expression levels of all three genes and metastatic rates or tumor responses to CRT. Mean overall survival in the patients with elevated SAG expression was 27.1 mo ± 3.9 mo [95% confidence interval (CI): 19.3-34.9], and in patients with reduced expression, it was 32.1 mo ± 2.5 mo (95% CI: 27.3-36.9). The corresponding values for Bcl-X(L) were 28.0 mo ± 4.1 mo (95% CI: 19.9-36.1) and 31.7 mo ± 2.9 mo (95% CI: 26.0-37.5), and those for Bak were 29.8 mo ± 3.7 mo (95% CI: 22.5-37.2) and 30.6 mo ± 2.4 mo (95% CI: 25.5-35.0), respectively.
  
  
  CONCLUSIONS
  Two-year survival rates significantly correlated with low SAG expression, and SAG may be a candidate gene for good prognosis, independent of therapeutic response of different individuals.
authors.affiliation: Clinic of Radiation Oncology, Dr. Lütfi Kırdar Kartal Education and Research Hospital, 34890 Istanbul, Turkey.
authors.forename: Sevgi A
authors.initials: SA
authors.lastname: Ozden
authors.forename: Hazan
authors.initials: H
authors.lastname: Ozyurt
authors.forename: Zerrin
authors.initials: Z
authors.lastname: Ozgen
authors.forename: Olca
authors.initials: O
authors.lastname: Kilinc
authors.forename: Mustafa
authors.initials: M
authors.lastname: Oncel
authors.forename: Aylin E
authors.initials: AE
authors.lastname: Gul
authors.forename: Nimet
authors.initials: N
authors.lastname: Karadayi
authors.forename: Nedime
authors.initials: N
authors.lastname: Serakinci
authors.forename: Beki
authors.initials: B
authors.lastname: Kan
authors.forename: Oya
authors.initials: O
authors.lastname: Orun
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy; D003937:Diagnosis, Differential; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012004:Rectal Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology / Q000628:therapy; D015996:Survival Rate; D016896:Treatment Outcome; D044767:Ubiquitin-Protein Ligases / Q000235:genetics* / Q000378:metabolism*; D050998:bcl-2 Homologous Antagonist-Killer Protein / Q000235:genetics / Q000378:metabolism; D051020:bcl-X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C494772:BAK1 protein, human; C494811:BCL2L1 protein, human; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein; C118307:RNF7 protein, human; D044767:Ubiquitin-Protein Ligases