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Updated: Aug 7, 2025

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma
08:07

Three-Dimensional Bone Extracellular Matrix Model for Osteosarcoma

Published on: April 12, 2019

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Secreted phosphoprotein 24 kD (Spp24) inhibits the growth of human osteosarcoma through the BMP-2/Smad signaling

Hongfang Chen1, Chenshuang Li2, Tangjun Zhou1

  • 1Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society
|March 8, 2023
PubMed

Insights

Secreted phosphoprotein 24 kD (Spp24) inhibits osteosarcoma (OS) growth by blocking BMP-2 signaling. This study shows Spp24 has therapeutic potential for skeletal tumors by promoting apoptosis and inhibiting proliferation.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Autocrine stimulation drives skeletal tumor growth.
  • Growth factor inhibitors can reduce tumor progression.

Purpose of the Study:

  • Investigate Secreted phosphoprotein 24 kD (Spp24) effects on osteosarcoma (OS) growth.
  • Determine Spp24's role with and without BMP-2 in vitro and in vivo.

Main Methods:

  • Utilized 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay and immunohistochemistry.
  • Employed subcutaneous and intratibial tumor models in nude mice.
  • Analyzed BMP-2/Smad signaling pathway activation.

Main Results:

  • Spp24 inhibited OS cell proliferation and promoted apoptosis.
  • BMP-2 enhanced tumor cell mobility and invasiveness; Spp24 inhibited these effects.
  • Spp24 inhibited BMP-2-induced Smad1/5/8 phosphorylation and Smad8 gene expression.
  • Spp24 significantly inhibited OS tumor growth in vivo.

Conclusions:

  • BMP-2/Smad pathway is crucial in OS pathogenesis.
  • Spp24 inhibits human OS growth induced by BMP-2 via Smad signaling interruption and apoptosis.
  • Spp24 shows potential as a therapeutic agent for OS and skeletal tumors.
Keywords:
BMP-2SmadSpp24autocrineosteosarcoma

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