PURPOSE: The purpose is to characterize alterations of the annexin I gene, its mRNA, and protein expression in esophageal squamous cell carcinoma. EXPERIMENTAL DESIGN: Fifty-six cases of esophageal squamous cell carcinoma were analyzed using four microsatellite markers flanking the annexin I gene (9q11-q21) to identify loss of heterozygosity. In addition, we performed (a) single-strand conformation polymorphism and DNA sequencing along the entire promoter sequence and coding region to identify mutations, (b) real-time quantitative reverse transcription-PCR of RNA from frozen esophageal squamous cell carcinoma tissue (n = 37) and in situ hybridization (n = 5) on selected cases to assess mRNA expression, and (c) immunohistochemistry (n = 44) to evaluate protein expression. The prevalence of the allelic variants identified in the first 56 patients was refined in 80 additional esophageal squamous cell carcinoma patients and 232 healthy individuals. RESULTS: Forty-six of 56 (82%) esophageal squamous cell carcinoma patients showed loss of an allele at one or more of the four microsatellite markers; however, only one (silent) mutation was seen. Two intragenic variants were identified with high frequency of allelic loss (A58G, 64%; L109L, 69%). Thirty of 37 (81%) esophageal squamous cell carcinoma patients showed reduced annexin I mRNA expression, which was confirmed by in situ hybridization, whereas annexin I protein expression was reduced in 79% of poorly differentiated tumor cell foci but in only 5% of well-differentiated tumor foci, although allelic loss on chromosome 9 was found in both tumor grades. CONCLUSIONS: Allelic loss of annexin I occurs frequently, whereas somatic mutations are rare, suggesting that annexin I is not inactivated in esophageal squamous cell carcinoma via a two-hit mechanism. A decrease in annexin I protein expression was confirmed, consistent with a quantitative decrease in mRNA expression, and appeared to be related to tumor cell differentiation. We conclude that annexin I is not the tumor suppressor gene corresponding to the high levels of loss of heterozygosity observed on chromosome 9 in esophageal squamous cell carcinoma; however, dysregulation of mRNA and protein levels is associated with this tumor type.
PURPOSE: The purpose is to characterize alterations of the annexin I gene, its mRNA, and protein expression in esophageal squamous cell carcinoma. EXPERIMENTAL DESIGN: Fifty-six cases of esophageal squamous cell carcinoma were analyzed using four microsatellite markers flanking the annexin I gene (9q11-q21) to identify loss of heterozygosity. In addition, we performed (a) single-strand conformation polymorphism and DNA sequencing along the entire promoter sequence and coding region to identify mutations, (b) real-time quantitative reverse transcription-PCR of RNA from frozen esophageal squamous cell carcinoma tissue (n = 37) and in situ hybridization (n = 5) on selected cases to assess mRNA expression, and (c) immunohistochemistry (n = 44) to evaluate protein expression. The prevalence of the allelic variants identified in the first 56 patients was refined in 80 additional esophageal squamous cell carcinomapatients and 232 healthy individuals. RESULTS: Forty-six of 56 (82%) esophageal squamous cell carcinomapatients showed loss of an allele at one or more of the four microsatellite markers; however, only one (silent) mutation was seen. Two intragenic variants were identified with high frequency of allelic loss (A58G, 64%; L109L, 69%). Thirty of 37 (81%) esophageal squamous cell carcinomapatients showed reduced annexin I mRNA expression, which was confirmed by in situ hybridization, whereas annexin I protein expression was reduced in 79% of poorly differentiated tumor cell foci but in only 5% of well-differentiated tumor foci, although allelic loss on chromosome 9 was found in both tumor grades. CONCLUSIONS:Allelic loss of annexin I occurs frequently, whereas somatic mutations are rare, suggesting that annexin I is not inactivated in esophageal squamous cell carcinoma via a two-hit mechanism. A decrease in annexin I protein expression was confirmed, consistent with a quantitative decrease in mRNA expression, and appeared to be related to tumor cell differentiation. We conclude that annexin I is not the tumor suppressor gene corresponding to the high levels of loss of heterozygosity observed on chromosome 9 in esophageal squamous cell carcinoma; however, dysregulation of mRNA and protein levels is associated with this tumor type.
Authors: Giang Huong Nguyen; Aaron J Schetter; David B Chou; Elise D Bowman; Ronghua Zhao; Jason E Hawkes; Ewy A Mathé; Kensuke Kumamoto; Yiqiang Zhao; Anuradha Budhu; Nobutoshi Hagiwara; Xin Wei Wang; Masao Miyashita; Alan G Casson; Curtis C Harris Journal: Clin Cancer Res Date: 2010-10-14 Impact factor: 12.531
Authors: Arunangshu Das; James D Bortner; Cesar A Aliaga; Aaron Baker; Anne Stanley; Bruce A Stanley; Matthew Kaag; John P Richie; Karam El-Bayoumy Journal: Prostate Date: 2012-08-21 Impact factor: 4.104
Authors: Mikiko Takikita; Nan Hu; Jian-Zhong Shou; Quan-Hong Wang; Carol Giffen; Philip R Taylor; Stephen M Hewitt Journal: BMC Cancer Date: 2009-09-03 Impact factor: 4.430