Prox1 and FOXC2 act as regulators of lymphangiogenesis and angiogenesis in oral squamous cell carcinoma

PLoS One. 2014 Mar 19;9(3):e92534. doi: 10.1371/journal.pone.0092534. eCollection 2014.

Abstract

Prospero homeobox 1 (Prox1) and forkhead box (FOX) C2 regulate angiogenesis and/or lymphangiogenesis. However, the detailed role and function of Prox1 and FOXC2 in cancer remains controversial. In the present study, we examined the expression of Prox1 and FOXC2 proteins in specimens from 163 cases with oral squamous cell carcinoma (OSCC). Furthermore, the role of Prox1 and FOXC2 in cancer cell growth and invasion was evaluated in cultured OSCC cells. Prox1 expression was significantly associated with local progression of the tumor (P = 0.0023), clinical stage (P<0.0001), lymphovessel density (LVD) (P<0.0001), nodal metastasis (P<0.0001), and worse prognosis (P<0.0001). Immunoreactivity of FOXC2 was strongly correlated with microvessel density (MVD) (P<0.0001) and poor prognosis (P = 0.0076). In vitro analysis demonstrated that Prox1 regulates cell growth, proliferation, invasion, and lymphangiogenesis by activating vascular endothelial growth factor (VEGF)-C expression. Furthermore, FOXC2 enhanced the expression level of Prox1 and promoted angiogenesis by enhancement of VEGF-A expression. Our results suggested that Prox1 and FOXC2 play key roles in OSCC progression and that further studies focusing on these proteins may yield useful insights for diagnosis and therapy of OSCC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Squamous Cell / genetics
  • Carcinoma, Squamous Cell / metabolism*
  • Cell Line, Tumor
  • Female
  • Forkhead Transcription Factors / genetics
  • Forkhead Transcription Factors / metabolism*
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism*
  • Humans
  • In Vitro Techniques
  • Lymphangiogenesis / genetics
  • Lymphangiogenesis / physiology*
  • Male
  • Middle Aged
  • Neovascularization, Pathologic / genetics
  • Neovascularization, Pathologic / metabolism
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism*

Substances

  • Forkhead Transcription Factors
  • Homeodomain Proteins
  • Tumor Suppressor Proteins
  • mesenchyme fork head 1 protein
  • prospero-related homeobox 1 protein

Grants and funding

A Grant-in-Aid for Scientific Research (C) from Japan Society for the Promotion of Science; http://www.jsps.go.jp/english/e-grants/index.html#. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.