Elevated expression of CTRP3/cartducin contributes to promotion of osteosarcoma cell proliferation.
CTRP3/cartducin, a novel secretory protein, is a member of the C1q and tumor necrosis factor (TNF)-related protein (CTRP) superfamily, and plays important roles in regulating both embryonic cartilage development and postnatal longitudinal bone growth. CTRP3/cartducin is expressed in human osteosarcomas. We hypothesized that CTRP3/cartducin might have a role in osteosarcoma tumor growth and metastasis. Murine osteosarcoma cell lines, NHOS and LM8, were used as a model. RT-PCR analysis showed that the mRNA level of CTRP3/cartducin was increased in these two murine osteosarcoma cell lines compared with its level in normal murine osteoblast MC3T3-E1 cells. Western blot analysis showed that the protein level of CTRP3/cartducin was also increased in these two osteosarcoma cell lines. Stimulation of NHOS and LM8 cells by CTRP3/cartducin promoted tumor cell growth but not migration in vitro. Further, CTRP3/cartducin stimulation led to the activation of extracellular signal-regulated kinase 1/2 (ERK1/2) in these two osteosarcoma cell lines. MAPK/ERK kinase 1/2 (MEK1/2) inhibitor, U0126, blocked CTRP3/cartducin-induced cell proliferation. These results suggest that CTRP3/cartducin expression may play a role in osteosarcoma tumor growth associated with activation of the ERK1/2 signaling pathway.
Department of Anatomy and Cell Biology, Graduate School of Dentistry, Osaka University, Osaka 565-0871, Japan.
Hironori
H
Akiyama
Souhei
S
Furukawa
Satoshi
S
Wakisaka
Takashi
T
Maeda
D054392:Adipokines; D000818:Animals; D001859:Bone Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D012516:Osteosarcoma / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D011506:Proteins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism; D015398:Signal Transduction; D013997:Time Factors; D015854:Up-Regulation
D054392:Adipokines; C428135:CORS26 protein, mouse; D047428:Protein Kinase Inhibitors; D011506:Proteins; D012333:RNA, Messenger; D011994:Recombinant Proteins; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3