Immunohistochemical detection of Def6 protein in oral cancer

Nowadays, oral cancer becomes global health issue and reaches 21st rank in Malaysian population. Def6 or IRF-4-binding proteins (IBP) that mostly produced in lymph node and thymus are associated with cell survival and cell proliferation. Def6 protein expression is often found in autoimmune diseases, but current studies also found Def6 in some cancers. In this study, we would like to detect Def6 protein expression in oral cancer. 36 formalin-fixed paraffin embedded tissues were selected for both test group (oral cancer) and control group (normal oral mucosa). The cases were retrieved from the archives of Faculty of Dentistry, University of Malaya, Kuala Lumpur. Immunohistochemistry (IHC) staining was manually performed using Def6 antibody (Abcam 1:300) and assessed quantitatively (positivity and staining intensity). Positive and negative controls were used to validate the IHC run. All data were then analysed using SPSS version 25.0. Control group was negative for Def6 expression. 29 cases (82.86%) of oral cancer were Def6 positive with 2.86% weak staining, 5.71% moderate staining and 74.28% strong staining intensity. There was significant difference between Def6 expression in normal oral mucosa and oral cancer (p