Risa Chaisuparat1, Seehachart Limpiwatana2, Sanida Kongpanitkul2, Somchai Yodsanga1, Bruno C Jham3. 1. Department of Oral Pathology, Developing Research Unit of Prevention and Therapy of Oral Cancers and Neoplasms by Herbal Medicine, Faculty of Dentistry, Chulalongkorn University, Pathumwan, Bangkok, Thailand. 2. Faculty of Dentistry, Chulalongkorn University, Pathumwan, Bangkok, Thailand. 3. College of Dental Medicine-Illinois, Midwestern University, Downers Grove, IL, USA.
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.
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.