Expression of phospho-p44/42MAPK in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) has been one of the most common cancers world-wide. Activation of MAPK family, in particular extracellular-signal-regulated kinase ERK by phosphorylation has been reported to be the indicator for the malignant proliferation in various malignancies. The aim of the present study was to determine quantitatively the degree of ERK phosphorylationin OSCC. Patients and Methods: A total of 48 paraffin embedded OSCC samples was retrieved. Immunohistochemical staining was done using monoclonal antibody phosphop44/42MAPK. 10 samples taken from retromolar area of otherwise healthy patients who underwent to impacted third molar surgery were used as controls. Samples were taken during the surgery. The ERK phosphorylation was detected using labelling index (LI). Subsequent correlation of LI with clinico-pathological parameters was performed. Results: ERK was detectable in all the OSCC cases, not in negative controls. The mean LI was 35.17%. However, there was no statistically significant difference between ERK activation and clinico-pathological variables except gender (p<0.01).Conclusion: It was determined that pERK (phosphorylated ERK) is indicating clearly tumour differentiation. Nevertheless, there was no correlation between the ERK phosphorylation and clinico-pathological parameters of OSCC. Thus, results may suggest pERK has got a role in oral carcinogenesis but no role during the progression of malignant proliferation which increases the severity in OSCC.