ONZIN Upregulation by Mutant p53 Contributes to Osteosarcoma Metastasis Through the CXCL5-MAPK Signaling Pathway

Cell Physiol Biochem. 2018;48(3):1099-1111. doi: 10.1159/000491976. Epub 2018 Jul 24.


Background/aims: Gain-of-function of mutant p53 is associated with a high rate of lung metastasis in osteosarcoma. To investigate the mechanism of mutant p53-induced osteosarcoma metastasis, expression array analysis was performed, comparing non-metastatic osteosarcomas from p53+/- mice with metastatic osteosarcomas from p53R172H/+ mice. Onzin (Plac8) was identified as one of the genes upregulated in p53R172H/+ mouse metastatic osteosarcomas. Accordingly, we investigated the role of ONZIN in human osteosarcoma metastasis.

Methods: ONZIN function and its downstream targets were examined in osteosarcoma cell lines. Assays related to tumorigenesis and metastasis, including cell migration, invasion, clonogenic survival, and soft agar colony formation, were performed in osteosarcoma cells. Additionally, mouse xenograft models were used to examine the role of ONZIN overpression in tumorigenesis in vivo. Lastly, 87 osteosarcoma patients were recruited to investigate the clinical relevance of ONZIN overexpression in metastasis and prognosis.

Results: ONZIN overexpression enhanced osteosarcoma cell proliferation, clonogenic survival, migration, and invasion independent of p53 status. Furthermore, ONZIN overexpression induced CXCL5 upregulation and resulted in increased ERK phosphorylation, which contributed to more aggressive osteosarcoma metastatic phenotypes. More importantly, overexpression of ONZIN in human osteosarcoma patients was closely associated with lung metastasis, poor prognoses, and survival.

Conclusions: Overexpression of ONZIN promotes osteosarcoma progression and metastasis, and can serve as a clinical biomarker for osteosarcoma metastasis and prognosis.

Keywords: Invasion; MAPK pathway; Migration; Mutant p53 gain-of-function; Osteosarcoma.

MeSH terms

  • Adult
  • Animals
  • Carcinogenesis
  • Cell Line, Tumor
  • Cell Proliferation
  • Chemokine CXCL5 / antagonists & inhibitors
  • Chemokine CXCL5 / genetics
  • Chemokine CXCL5 / metabolism*
  • Female
  • Humans
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Mitogen-Activated Protein Kinases / metabolism*
  • Osteosarcoma / metabolism
  • Osteosarcoma / pathology
  • Proteins / antagonists & inhibitors
  • Proteins / genetics
  • Proteins / metabolism*
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Signal Transduction
  • Transplantation, Heterologous
  • Tumor Suppressor Protein p53 / antagonists & inhibitors
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism*


  • CXCL5 protein, human
  • Chemokine CXCL5
  • PLAC8 protein, human
  • Proteins
  • RNA, Small Interfering
  • TP53 protein, human
  • Tumor Suppressor Protein p53
  • Mitogen-Activated Protein Kinases