Zivar Salehi1, Farhad Mashayekhi. 1. Department of Biology, Faculty of Sciences, The University of Guilan, Rasht, Iran. geneticzs@yahoo.co.uk
Abstract
OBJECTIVES: The eukaryotic initiation factor 4E (eIF4E) has been shown to play a key role in cell growth, and several studies have documented an increased expression of eIF4E in a number of solid tumors, including breast, bladder, cervical and head and neck cancers. The aim of this study was to determine the level of expression of eIF4E and eIF4E-binding protein 1 (4E-BP1) in esophageal cancer. DESIGN AND METHODS: Tumor and normal adjacent tissue samples (as controls) were obtained from 99 patients with esophageal cancer. eIF4E and 4E-BP1 levels were determined by using Western blot analysis. eIF4E was purified by affinity chromatography using m(7)GTP-sepharose, and the levels of 4E-BP1 bound to eIF4E were determined. RESULTS: : In cancerous esophageal tissues, eIF4E level was elevated by a mean of 12.59 +/- 1.66-fold, and 4E-BP1 was elevated by a mean of 15.76 +/- 2.45-fold when compared to normal adjacent tissues. Both eIF4E and 4E-BP1 expressions were higher in cancerous compared to noncancerous esophageal tissues. CONCLUSIONS: A higher expression of eIF4E was correlated with advanced stages. The inverse relationship found between the increases in 4E-BP1 levels observed in esophagus tumors and lymph node involvement would support the hypothesis that the overexpression of eIF4E can be involved in tumorigenesis and a possible role of 4E-BP1 as a prognostic factor in esophageal cancer.
OBJECTIVES: The eukaryotic initiation factor 4E (eIF4E) has been shown to play a key role in cell growth, and several studies have documented an increased expression of eIF4E in a number of solid tumors, including breast, bladder, cervical and head and neck cancers. The aim of this study was to determine the level of expression of eIF4E and eIF4E-binding protein 1 (4E-BP1) in esophageal cancer. DESIGN AND METHODS: Tumor and normal adjacent tissue samples (as controls) were obtained from 99 patients with esophageal cancer. eIF4E and 4E-BP1 levels were determined by using Western blot analysis. eIF4E was purified by affinity chromatography using m(7)GTP-sepharose, and the levels of 4E-BP1 bound to eIF4E were determined. RESULTS: : In cancerous esophageal tissues, eIF4E level was elevated by a mean of 12.59 +/- 1.66-fold, and 4E-BP1 was elevated by a mean of 15.76 +/- 2.45-fold when compared to normal adjacent tissues. Both eIF4E and 4E-BP1 expressions were higher in cancerous compared to noncancerous esophageal tissues. CONCLUSIONS: A higher expression of eIF4E was correlated with advanced stages. The inverse relationship found between the increases in 4E-BP1 levels observed in esophagus tumors and lymph node involvement would support the hypothesis that the overexpression of eIF4E can be involved in tumorigenesis and a possible role of 4E-BP1 as a prognostic factor in esophageal cancer.
Authors: Tanasa S Osborne; Ling Ren; John H Healey; Lauren Q Shapiro; Alexander J Chou; Richard G Gorlick; Stephen M Hewitt; Chand Khanna Journal: J Pediatr Hematol Oncol Date: 2011-10 Impact factor: 1.289
Authors: L J Coleman; M B Peter; T J Teall; R A Brannan; A M Hanby; H Honarpisheh; A M Shaaban; L Smith; V Speirs; E T Verghese; J N McElwaine; T A Hughes Journal: Br J Cancer Date: 2009-04-14 Impact factor: 7.640