MAP kinase modulation in squamous cell carcinoma of the oral cavity.

BACKGROUND Oral squamous cell carcinoma (OSCC) represents the sixth most diffused cancer in developed countries. Mitogen-activated protein kinases (MAPKs) are proteins which transduce a vast array of extracellular signals into intracellular responses. The role of MAPK signalling pathway in cancer is not completely understood. MATERIALS AND METHODS In this study, we attempted to specifically evaluate the activation state of MAPK in OSCC. MAPK expression and activation were analyzed by immunoblotting in thirty tissue samples of OSCC and their paired nonneoplastic perilesional tissues. On the same tissues, the activation and expression of MAPK JNK/SAPK were also evaluated by ELISA assay. RESULTS Analyzing the levels of phospho-ERK1/2(p44/p42), a statistically significant reduction was observed in tumors compared to normal tissues. No statistically significant difference between tumor and control tissue was found for p38MAPK or JNK/SAPK. CONCLUSION These results suggest that a reduction in ERK1/2(p44/p42) phosphorylation is correlated with tumor growth in OSCC.