PIK3CB and K-ras in oral squamous Cell carcinoma. A possible cross-talk!

Abstract

Background: PIK3 and K-ras are signal transducing proteins involved and mediating many responses related to cell cycle growth regulation. Until date, there has been only limited evidence about the expression of K-ras and PKI3CB in oral squamous cell carcinoma (OSCC). AIMS : This study aimed to examine both proteins in OSCC and their relation to clinic- pathological findings. Setting and Design: A total of 31 formalin-fixed paraffin-embedded specimens of OSCC were selected in this study. PIK3CB and K-ras expressions were detected using standard immunohistochemical techniques. Materials and Methods: PIK3CB and k-ras immune reactivity was semi-quantitatively evaluated in at least five representative fields at 400X magnification and recorded as percentage of PIK3CB and k-ras positive tumor cells over the total number of cells examined in the same area. Results and Conclusion: All examined specimens of OSCC were positive for monoclonal antibodies directed against PIK3CB and K-ras proteins especially at advanced stage of the disease. No significant relation was observed between the tested proteins and the clinic-pathological findings of OSCC; however a highly significant direct relationship was observed between K-ras and PIK3CB. This lead to conclusion that both K-ras and PIK3CB signaling pathway were activated in the advanced stage of OSCC, and possibly a cross-talk between them. This could make these mutant proteins a potential target for an effective molecular therapy.

Keywords

• K-ras, PIK3CB, signal transduction, SCC