title: Overexpression of immunoglobulin (CD79a) binding protein1 (IGBP-1) in small lung adenocarcinomas and its clinicopathological significance.
abstract: Immunoglobulin binding protein 1 (IGBP-1) was initially identified as a signal transduction molecule coprecipitating with MB1 (Igα) of the B cell antigen receptor (BCR) complex and was later found to be broadly expressed. Immunoglobulin binding protein 1 has been characterized as an associated and regulatory component of the catalytic subunits of protein phosphatase 2A (PP2A), which is the most abundant phosphatase and plays important roles in cell growth and cell cycle control. The aim of this study was to investigate the expressional characteristics of IGBP-1 and PP2Ac during pulmonary adenocarcinogenesis. The positivity rate of IGBP-1 increased during the course of sequential progression from non-invasive carcinoma (8/30, 26.7%) to invasive adenocarcinoma (37/46, 80.4%) among cases that showed areas of lepidic growth. In contrast, all of the small adenocarcinomas showing a non-lepidic growth pattern were positive for IGBP-1 (20/20, 100%). All cancers that proved ultimately fatal were positive for IGBP-1, and log-rank analysis showed that IGBP-1 positivity was significantly correlated with a poor prognosis. In contrast, atypical adenomatous hyperplasias and lung adenocarcinomas were uniformly positive for PP2Ac. Protein phosphatase 2A was not associated with carcinoma progression. Thus we have demonstrated that IGBP-1 is expressed universally in advanced lung adenocarcinomas, and that its overexpression is significantly related to outcome.
authors.affiliation: Department of Pathology Thoracic Surgery, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Sakashita
authors.forename: Dongping
authors.initials: D
authors.lastname: Li
authors.forename: Naohumi
authors.initials: N
authors.lastname: Nashima
authors.forename: Yuko
authors.initials: Y
authors.lastname: Minami
authors.forename: Shuuichiro
authors.initials: S
authors.lastname: Furuya
authors.forename: Yukio
authors.initials: Y
authors.lastname: Morishita
authors.forename: Keisei
authors.initials: K
authors.lastname: Tachibana
authors.forename: Yukio
authors.initials: Y
authors.lastname: Sato
authors.forename: Masayuki
authors.initials: M
authors.lastname: Noguchi
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000230:Adenocarcinoma / Q000378:metabolism* / Q000401:mortality / Q000556:secondary / Q000601:surgery; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D005260:Female; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D007564:Japan / Q000453:epidemiology; D008175:Lung Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology / Q000601:surgery; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D018832:Molecular Chaperones; D009367:Neoplasm Staging; D054648:Protein Phosphatase 2 / Q000378:metabolism*; D015996:Survival Rate
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D014408:Biomarkers, Tumor; C490467:IGBP1 protein, human; D047908:Intracellular Signaling Peptides and Proteins; D018832:Molecular Chaperones; D054648:Protein Phosphatase 2