title: Lack of Bax expression is associated with irinotecan-based treatment activity in advanced colorectal cancer patients.
abstract: BACKGROUND
  Currently, first-line chemotherapy in advanced colorectal cancer is not tailored on predictive biomarkers. Bax proapoptotic protein may correlate to chemosensitivity and differential response to irinotecan or oxaliplatin-based combinations.
  
  
  METHODS
  Bax expression was assessed by immunohistochemistry in 49 advanced colorectal cancer patients enrolled at our institution from 2002 to 2004 within a multicenter, phase II, randomized trial of first-line UFT/leucovorin/irinotecan (TEGAFIRI) versus UFT/leucovorin/oxaliplatin (TEGAFOX).
  
  
  RESULTS
  Bax-positive and negative samples were 49 and 51 %. Response was significantly lower in Bax positive (25 %) as compared to Bax negative (56 %) (Odds ratio = 0.26; p = 0.03). No significant difference was noted in TEGAFOX subgroup; in TEGAFIRI arm, responses were lower in Bax positive (18 %) than Bax negative (67 %) (Odds ratio = 0.11; p = 0.03). No difference in terms of progression-free and overall survival was observed according to Bax.
  
  
  CONCLUSIONS
  Bax-negative colorectal cancer may identify a specific phenotype of patients with significantly higher chance to respond to doublet irinotecan-based chemotherapy.
authors.affiliation: Medical Oncology Unit 1, Medical Oncology Department, Fondazione IRCCS Istituto Nazionale Dei Tumori, Via Venezian 1, 20133, Milan, Italy. filippo.pietrantonio@istitutotumori.mi.it
authors.forename: F
authors.initials: F
authors.lastname: Pietrantonio
authors.forename: P
authors.initials: P
authors.lastname: Biondani
authors.forename: M
authors.initials: M
authors.lastname: Milione
authors.forename: F
authors.initials: F
authors.lastname: Melotti
authors.forename: G
authors.initials: G
authors.lastname: Bertarelli
authors.forename: F
authors.initials: F
authors.lastname: Perrone
authors.forename: F
authors.initials: F
authors.lastname: de Braud
authors.forename: L
authors.initials: L
authors.lastname: Mariani
authors.forename: G
authors.initials: G
authors.lastname: Fanetti
authors.forename: D
authors.initials: D
authors.lastname: Cortinovis
authors.forename: M
authors.initials: M
authors.lastname: Di Bartolomeo
mesh_terms: D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002166:Camptothecin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000627:therapeutic use; D015179:Colorectal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D000077146:Irinotecan; D002955:Leucovorin / Q000008:administration & dosage / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents; D051028:bcl-2-Associated X Protein; D000077146:Irinotecan; D002955:Leucovorin; D002166:Camptothecin