Osteopontin modulates malignant pleural mesothelioma cell functions in vitro.
BACKGROUND
Although serum osteopontin (OPN) concentration is elevated in patients with malignant pleural mesothelioma (MPM), the role of OPN in the pathogenesis and development of MPM remains unknown.


METHODS
To determine the roles of OPN in MPM, immunohistochemical staining was performed to investigate the concentration of OPN in the pleural tumor of patients with mesothelioma; cell adhesion, proliferation and migration assays of H28 cells, an MPM cell line, were also carried out in vitro.


RESULTS
H28 cells cultured on OPN-coated plates revealed enhanced adhesion, proliferation, migration, cell survival and phosphorylated focal adhesion kinase activities. As expected, these enhancements were markedly suppressed with the addition of anti-alphavbeta3 antibody or arginine-glycine-aspartic acid serine (RGDS) peptide to the medium.


CONCLUSIONS
OPN is speculated to play an important role in the enhancement of adhesion, proliferation and migration activities of H28 cells, presumably by interacting with the alphavbeta3 integrin.
Ohashi
Rina
R
Department of Respiratory Medicine, Juntendo University, School of Medicine, Bunkyo-Ku, Tokyo 113-8421, Japan. rinaohas@juntendo.ac.jp
Tajima
Ken
K
Takahashi
Fumiyuki
F
Cui
Ri
R
Gu
Tao
T
Shimizu
Kazue
K
Nishio
Kazuto
K
Fukuoka
Kazuya
K
Nakano
Takashi
T
Takahashi
Kazuhisa
K
D017209:Apoptosis; D015153:Blotting, Western; D002448:Cell Adhesion; D002465:Cell Movement; D049109:Cell Proliferation; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D047468:Immunoprecipitation; D066298:In Vitro Techniques; D039302:Integrin alphaVbeta3 / Q000378:metabolism; D008654:Mesothelioma / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D009842:Oligopeptides / Q000378:metabolism; D053495:Osteopontin / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D010997:Pleural Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D039302:Integrin alphaVbeta3; D009842:Oligopeptides; D012333:RNA, Messenger; D053495:Osteopontin; C049554:glycyl-arginyl-glycyl-aspartyl-serine; D051416:Focal Adhesion Protein-Tyrosine Kinases