BACKGROUND: The regulation of programmed cell death, or apoptosis, is crucial for normal development and for the maintenance of homeostasis. It has been shown that the novel antiapoptotic protein Bax inhibitor-1 (BI-1) represents a new type of regulator of cell death pathways controlled by Bcl-2 and Bax. METHODS: Surgically resected lung specimens were obtained from 32 patients with peripheral adenocarcinomas, and BI-1 gene expression was examined and compared with expression of the p53, bcl-2 and Bax genes. RESULTS: Fourteen of 32 tumors (43.8%) were positive for BI-1 gene expression by in situ hybridization. BI-1 gene expression in tumor specimens was significantly higher in adenocarcinomas with bronchioloalveolar carcinoma (BAC) and in adenocarcinomas of mixed subtypes with bronchioloalveolar spreading (14 of 17 tumors; 82.4%) than in carcinomas without it spreading. Patients who had BI-1-positive adenocarcinoma showed a relatively favorable prognosis compared with patients who had BI-1-negative adenocarcinoma. Eleven of 32 tumors (34.4%) were positive for the p53 protein, only 1 of 32 tumors (3.1%) was positive for the Bcl-2 protein, and 26 of 32 tumors (81.3%) were positive for the Bax protein. Protein expressions of p53, Bcl-2, and Bax, as detected by immunohistochemistry, were not associated with BI-1 gene expression. CONCLUSIONS: BI-1 gene expression was restricted to tumor cells with lepidic growth and was a prognostic factor for peripheral-type adenocarcinoma. It is believed that BI-1 gene expression is conserved evolutionarily and may act as a key regulator of the apoptotic pathway in BAC. Copyright (c) 2005 American Cancer Society.
BACKGROUND: The regulation of programmed cell death, or apoptosis, is crucial for normal development and for the maintenance of homeostasis. It has been shown that the novel antiapoptotic protein Bax inhibitor-1 (BI-1) represents a new type of regulator of cell death pathways controlled by Bcl-2 and Bax. METHODS: Surgically resected lung specimens were obtained from 32 patients with peripheral adenocarcinomas, and BI-1 gene expression was examined and compared with expression of the p53, bcl-2 and Bax genes. RESULTS: Fourteen of 32 tumors (43.8%) were positive for BI-1 gene expression by in situ hybridization. BI-1 gene expression in tumor specimens was significantly higher in adenocarcinomas with bronchioloalveolar carcinoma (BAC) and in adenocarcinomas of mixed subtypes with bronchioloalveolar spreading (14 of 17 tumors; 82.4%) than in carcinomas without it spreading. Patients who had BI-1-positive adenocarcinoma showed a relatively favorable prognosis compared with patients who had BI-1-negative adenocarcinoma. Eleven of 32 tumors (34.4%) were positive for the p53 protein, only 1 of 32 tumors (3.1%) was positive for the Bcl-2 protein, and 26 of 32 tumors (81.3%) were positive for the Bax protein. Protein expressions of p53, Bcl-2, and Bax, as detected by immunohistochemistry, were not associated with BI-1 gene expression. CONCLUSIONS:BI-1 gene expression was restricted to tumor cells with lepidic growth and was a prognostic factor for peripheral-type adenocarcinoma. It is believed that BI-1 gene expression is conserved evolutionarily and may act as a key regulator of the apoptotic pathway in BAC. Copyright (c) 2005 American Cancer Society.
Authors: Renata Sano; Ying-Chen Claire Hou; Michael Hedvat; Ricardo G Correa; Chih-Wen Shu; Maryla Krajewska; Paul W Diaz; Craig M Tamble; Giovanni Quarato; Roberta A Gottlieb; Masaya Yamaguchi; Victor Nizet; Russell Dahl; David D Thomas; Stephen W Tait; Douglas R Green; Paul B Fisher; Shu-Ichi Matsuzawa; John C Reed Journal: Genes Dev Date: 2012-05-15 Impact factor: 11.361