title: Identification and evaluation of metastasis-related proteins, oxysterol binding protein-like 5 and calumenin, in lung tumors.
abstract: Metastasis is an important prognosis factor in lung cancer, therefore, it is imperative to identify target molecules and elucidate molecular mechanism of metastasis for developing new therapeutics and diagnosis methods. We searched for metastasis-related proteins by utilizing a novel antibody proteome technology developed in our laboratory that facilitated efficient screening of useful target proteins. Two-dimensional differential in-gel electrophoresis (2D-DIGE) analysis identified sixteen proteins, which were highly expressed in metastatic lung cancer cells, as protein candidates. Monoclonal single-chain variable fragments (scFvs) binding to candidates were isolated from a scFv-displaying phage library by affinity selection. Tissue microarray analysis of scFvs binding to candidates revealed that oxysterol binding protein-like 5 (OSBPL5) and calumenin (CALU) were expressed at a significantly higher levels in the lung tissues of metastasis-positive cases than that in the metastasis-negative cases (OSBPL5; p=0.0156, CALU; p=0.0055). Furthermore, 80% of OSBPL5 and CALU double-positive cases were positive for lymph node metastasis. Consistent with these observations, overexpression of OSBPL5 and CALU promoted invasiveness of lung cancer cells. Conversely, knockdown of these proteins using respective siRNAs reversed the invasiveness of the lung cancer cells. Moreover, these proteins were expressed in lung tumor tissues, but not in normal lung tissues. In conclusion, OSBPL5 and CALU are related to metastatic potential of lung cancer cells, and they could be useful targets for cancer diagnosis and also for development of drugs against metastasis.
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Nagano
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Sunao
authors.initials: S
authors.lastname: Imai
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Xiluli
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Yoshioka
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Abe
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Mukai
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Haruhiko
authors.initials: H
authors.lastname: Kamada
authors.affiliation: Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
authors.forename: Shinsaku
authors.initials: S
authors.lastname: Nakagawa
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tsutsumi
authors.affiliation: Laboratory of Biopharmaceutical Research, National Institute of Biomedical Innovation, Ibaraki, Osaka 567-0085, Japan.
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Tsunoda
mesh_terms: D002135:Calcium-Binding Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology*; D009362:Neoplasm Metastasis; D019151:Peptide Library; D040901:Proteomics / Q000379:methods; D011987:Receptors, Steroid / Q000378:metabolism*; D057825:Two-Dimensional Difference Gel Electrophoresis / Q000379:methods; D015854:Up-Regulation; D000098825:Oxysterol Binding Proteins
chemical_list: C510527:CALU protein, human; D002135:Calcium-Binding Proteins; D019151:Peptide Library; D011987:Receptors, Steroid; D000098825:Oxysterol Binding Proteins