The Akt/mTOR pathway is activated in verrucous carcinoma of the oral cavity

J Oral Pathol Med. 2016 Sep;45(8):581-5. doi: 10.1111/jop.12422. Epub 2016 Jan 17.

Abstract

Background: The Akt/mTOR pathway is activated in many malignancies, including oral squamous cell carcinoma (OSCC). However, the role of the Akt/mTOR pathway in oral verrucous carcinoma (OVC), a low-grade variant of OSCC, remains unknown. Thus, the objective of this study was to investigate the activation level of important markers of the Akt/mTOR pathway in OVC and to compare the results with OSCC samples.

Methods: The expression of p-Akt (Thr308), p-Akt (Ser473), and p-RPS6 was evaluated by immunohistochemistry in 30 OSCC cases, 18 OVC cases, and 30 control cases (normal epithelium overlying fibromas). Statistical analysis was performed to determine the differences in protein expression between samples.

Results: All OVC cases were positive for p-Akt (Thr308), p-Akt (Ser473), and p-RPS6. There were significant differences in expression level of all studied proteins between OVC and control, as well as between OVC and OSCC. However, OVC showed significant lower staining scores than OSCC.

Conclusions: Our findings demonstrate that the Akt/mTOR pathway is upregulated in OVC, indicating a role for this pathway in the development and progression of this malignancy.

Keywords: Akt; mTOR; ribosomal protein S6; squamous cell carcinoma; verrucous carcinoma.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Squamous Cell / metabolism
  • Carcinoma, Squamous Cell / pathology
  • Carcinoma, Verrucous / enzymology*
  • Carcinoma, Verrucous / metabolism
  • Carcinoma, Verrucous / pathology
  • Female
  • Fibroma / pathology
  • Humans
  • Immunohistochemistry
  • Male
  • Middle Aged
  • Mouth Neoplasms / enzymology*
  • Mouth Neoplasms / metabolism
  • Mouth Neoplasms / pathology
  • Proto-Oncogene Proteins c-akt / metabolism*
  • Ribosomal Protein S6 / metabolism
  • TOR Serine-Threonine Kinases / metabolism*
  • Up-Regulation

Substances

  • Ribosomal Protein S6
  • MTOR protein, human
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases