Altered expression of HSP70 in oral lichen planus

BACKGROUND: Oral lichen planus (OLP), a well-known mucocutaneous lesion has been the center of debate regarding its obscure etiopathogenesis. Recent highlight has been placed on the role of autoimmunity and a sect of constitutional molecules, the native chaperones HSP70, proposed to be important in the onset and progress of disease. AIM: To substantiate a potential role of HSP70 in the pathogenesis of oral lichen planus. SETTINGS AND DESIGN: The study involved immunohistochemical (IHC) analyses in a laboratory under monitored conditions. It was a retrospective study on clinically and histopathologically confirmed specimens. MATERIALS AND METHODS: 30 samples of confirmed cases of OLP were selected and grouped on the basis of the thickness of the epithelial layer into atrophic, normal (classical) and acanthotic. An immunohistochemical analysis of the expression of HSP70 protein was done, followed by a quantitative and qualitative analysis of the stained layers. STATISTICAL ANALYSES: A Z test was performed to estimate the difference observed between two sample proportions. The statistics was given at 1% level of significance i.e. P<0.01. RESULTS: An increased expression of HSP70 was noted in the basal and suprabasal cells of the epithelium of OLP. A higher count and intensity of HSP70 expression was seen in the basal layer of the epithelium. Greater expression was noted in the epithelium of the atrophic group. CONCLUSION: The expression pattern of HSP70 positively implicates it in the pathogenesis of OLP.