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. 2009 Apr 15;18(8):1464-70.
doi: 10.1093/hmg/ddp057. Epub 2009 Feb 19.

Notch signaling contributes to the pathogenesis of human osteosarcomas

Feyza Engin  1 , Terry Bertin, Ou Ma, Ming Ming Jiang, Lisa Wang, Richard E Sutton, Lawrence A Donehower, Brendan Lee
Affiliations

Notch signaling contributes to the pathogenesis of human osteosarcomas

Feyza Engin et al. Hum Mol Genet. .

Abstract

Notch signaling plays an important role in developmental processes and adult tissue homeostasis. Altered Notch signaling has been associated with various diseases including cancer. While the importance of altered Notch signaling in cancers of hematopoietic and epithelial origins has been established, its role in tumors of mesenchymal origin is less clear. Here, we report that human osteosarcoma cell lines and primary human osteosarcoma tumor samples show significant up-regulation of Notch, its target genes and Osterix. Notch inhibition by gamma-secretase inhibitors or by using lentiviral mediated expression of dominant negative Mastermind-like protein (DN-MAML) decreases osteosarcoma cell proliferation in vitro. In vivo, established human tumor xenografts in nude mice show decreased tumor growth after chemical or genetic inhibition of Notch signaling. Finally, transcriptional profiling of osteosarcomas from p53 mutant mice confirmed up-regulation of Notch1 target genes Hes1, Hey1 and its ligand Dll4. Our data suggest that activation of Notch signaling contributes to the pathogenesis of human osteosarcomas and its inhibition may be a therapeutic approach for the treatment of this mesenchymal tumor.

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Figures

Figure 1.
Figure 1.
Notch Signaling is up regulated in human osteosarcoma. (A) Expression of Notch1, Jagged-1, Osterix and known Notch1 target genes Hey-2 and Hes-1 by Q-RT–PCR. Tumor RNA was obtained from (n = 7) untreated, and (n = 3) treated osteosarcoma patients (OS Patients), and (n = 3) control human osteoblasts.
Figure 2.
Figure 2.
Chemical inhibition of Notch signaling reduces proliferation of human osteosarcoma cell lines. (A) Proliferation of human SaOs2 osteosarcoma cells were measured by BrdU incorporation after treatment of these cells either with γ-secretase inhibitor (DAPT) for 24 h with the indicated doses or another γ-secretase inhibitor Compound E (500 nM), *P < 0.05. (B) Proliferation of two additional human osteosarcoma cell lines i.e. SJSA and CRL-1423 were measured by BrdU incorporation after treatment of these cells with 10 uM DAPT for 24 hours. (C) Cell viability of human SaOs2 osteosarcoma cells was measured by counting Trypan blue positive cells after adding increasing dosages of DAPT at indicated time periods. (D) SaOs2 cells were transduced either with a control vector or a lentivirus expressing dominant negative Mastermind like-1 (DN-MAML). The cells were sorted for YFP and the positive cells were re-plated for the measurement of BrdU incorporation, *P < 0.05.
Figure 3.
Figure 3.
Genetic and chemical inhibition of Notch signaling reduces tumor burden in nude mice. (A) Mean tumor volume in nude mice after inoculated with osteosacoma cells expressing either lentivirus-mediated YFP or DN-MAML1. (B) Pharmacological inhibition of Notch signaling via DAPT. Mice were injected with 125 mg/kg DAPT daily for 22 days.
Figure 4.
Figure 4.
Osteosarcomas from p53 mutant mice, exhibit up-regulation of Notch and its target genes. (A) mRNA expression of Notch and Notch target genes as measured by RNA microarray analysis. Expression levels are relative to MC3T3 osteoblastic cells (left most lane). Red indicates high expression relative to MC3T3 cells and green represents low expression (see logarithmic scale at upper right). OS: osteosarcoma. Each lane represents a different osteosarcoma sample, and sample names are labeled above the lanes. Some genes have more than one row of data, which indicate that there is more than one probe for the same gene on the microarray chip. (B) Expression of Notch ligand Dll4 and known Notch1 target genes Hes-1 and Hey-1 in osteosarcomas of p53+/− mice by Q-RT–PCR. Tumor RNA was obtained from p53+/− mice (n = 3), and calvarial RNA obtained from wt mice (n = 3) was used as a control, *P < 0.05.
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References

    1. Bray S.J. Notch signalling: a simple pathway becomes complex. Nat. Rev. Mol. Cell. Biol. 2006;7:678–689. - PubMed
    1. Koch U., Radtke F. Notch and cancer: a double-edged sword. Cell Mol. Life Sci. 2007;64:2746–2762. - PMC - PubMed
    1. Miele L., Golde T., Osborne B. Notch signaling in cancer. Curr. Mol. Med. 2006;6:905–918. - PubMed
    1. Roy M., Pear W.S., Aster J.C. The multifaceted role of Notch in cancer. Curr. Opin. Genet. Dev. 2007;17:52–59. - PubMed
    1. Gridley T. Notch signaling and inherited disease syndromes. Hum. Mol. Genet. 2003;12(Spec no. 1):R9–R13. - PubMed

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