Beclin-1 as a potential prognostic marker in correlation with E-cadherin in oral lichen planus and oral squamous cell carcinoma: an immunohistochemical analysis

Abstract

Background/aim Oral lichen planus (OLP) is a chronic, unexceptional, frequent disease of inflammatory origin, autoimmune background with unspecified etiology. Also it has been regarded as an oral potentially malignant disorder and reflects the potential hazard of malignant transformation into oral squamous cell carcinoma (OSCC). Beclin-1 happens to be one of the proteins regulating autophagy, where its dysfunction has been involved in various disorders. The function of Beclin-1, as per a marker for autophagy, still needs to be verified in oral premalignant lesions and their progression to OSCC. E-cadherin is an integral intercellular epithelial component responsible for intercellular adhesion, in which its down-expression denotes diminished cellular adhesion and propensity for invasion. Our work aimed to explore the levels of Beclin-1 and E-cadherin in erosive and nonerosive OLP and OSCC to assess the possible role of autophagy in the pathogenesis of OLP and estimate the malignant potential in each OLP type. Materials and methods This retrospective study was carried out in the pathology unit Ain Shams University Specialized Hospital. Sixty formalin-fixed paraffin-embedded tissue blocks, along with their clinicopathologic records, were retrieved from the archives of the Department of Oral Pathology, Faculty of Dentistry, Ain Shams University, Egypt. They were classified into three groups (20 each) as follows: group 1: the negative control group; group 2: comprised OLP cases, subdivided into two groups (10 each): group 2A, the erosive type and group 2B, the nonerosive type and group 3: comprised the OSCC cases, subdivided into two groups (10 each): group 3A, well-differentiated OSCC and group 3B, moderately differentiated OSCC. Immunohistochemistry was utilized to assess the expression levels of both Beclin-1, as a marker of autophagy and E-cadherin, as a marker of invasiveness and aggressiveness, to validate the malignant transformation potential. Results The present result obtained significant increases (P<0.05) in the levels of Beclin-1in a group of patients with OLP, the erosive type (G2A), and both groups of OSCC cases (G3A and B), while G3B was the highest level. Regarding E-cadherin, a significant decrease (P<0.05) was found in their levels in all groups of OLP and OSCC cases, compared to the control group; however group G3B exhibited the lowest reduction. Correlation between Beclin-1 and E-cadherin revealed an insignificant correlation between the two markers in all groups, except a significant negative correlation (r=−0.9, P<0.03) was found in a group of OLP patients with erosive type. Conclusion Beclin-1 could potentially be an important prognostic marker in OLP and OSCC. Low levels of E-cadherin expression in erosive OLP indicate greater potential for invasiveness, migration capability and a higher tendency to malignant transformation, which was found comparable to OSCC.

Keywords

• autophagy
• beclin-1
• e-cadherin
• oral lichen planus
• oral squamous cell carcinoma