Journal of Cancer Research and Clinical Oncology

, Volume 135, Issue 5, pp 739–747

Frequent inactivation of RUNX3 by promoter hypermethylation and protein mislocalization in oral squamous cell carcinomas

Authors

  • Feng Gao
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
  • Canhua Huang
    • State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University
  • Mei Lin
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
  • Zhi Wang
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
  • Jun Shen
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
  • Haiyuan Zhang
    • Oncology Research Institute, National University of Singapore
  • Lu Jiang
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
    • State Key Laboratory for Dental Medicines and West China College of StomatologySichuan University
Original Paper

DOI: 10.1007/s00432-008-0508-x

Cite this article as:
Gao, F., Huang, C., Lin, M. et al. J Cancer Res Clin Oncol (2009) 135: 739. doi:10.1007/s00432-008-0508-x

Abstract

Purpose

RUNX3 is a functionally important component in transforming growth factor-beta (TGF-β) mediated signaling pathway. Epigenetic silencing expression of RUNX3, as well as aberrant cytoplasmic retention of RUNX3 protein are causely involved in gastric carcinogenesis. Here, we examined the expression of RUNX3 gene and protein in oral squamous cell carcinomas (OSCCs) and analyzed the methylation status of RUNX3 promoter region.

Methods

About 10 normal oral mucosa and 30 OSCCs were collected to examine RUNX3 expression by RT-PCR analysis and immunohistochemistry assay using anti-RUNX3 monoclonal antibody R3-6E9. Methylation-specific PCR was carried out on the same specimens to analyze the methylation status of RUNX3 promoter. In addition, the stored paraffin-embedded specimens, including 40 oral leucoplakia (OLK) and 120 OSCCs, were examined by immunohistochemistry assay.

Results

RUNX3 gene and protein were underexpressed in OSCCs due to promoter hypermethylation. Protein mislocalization occured frequently. Both downregulation of RUNX3 protein expression (P = 0.001) and protein mislocalization (P = 0.001) were correlated with the differentiation grades in OSCCs.

Conclusions

RUNX3 plays an important role in oral carcinogenesis. It may be a useful diagnostic marker and a potential therapeutic target for OSCC.

Keywords

HypermethylationRunt-related transcription factor 3Oral squamous cell carcinomaMethylation-specific PCRProtein mislocalization

Abbreviation

MSP

Methylation-specific PCR

OLK

Oral leukoplakia

OSCC

Oral squamous cell carcinoma

RUNX3

Runt-related transcription factor 3

TGF-β

Transforming growth factor-β

Copyright information

© Springer-Verlag 2008