Aldehyde dehydrogenase isoform 1 as an indicator in the malignant potential of cutaneous lichen planus

Introduction: Hypertrophic variant of cutaneous lichen planus (CLP) is a chronic variant with controversial malignant association. Since aldehyde dehydrogenase isoform 1 (ALDH1) is considered as a prognostic marker in various cancers and its expression was significantly associated with malignant transformation in the oral type of lichen planus. So we decided to assess the ALDH1 expression in CLP in order to know the role of this biomarker in the CLP. Materials and Methods: Thirty blocks of CLP from the archive of Dermatology Department of Babol University of Medical Sciences and 30 blocks of normal skin as the control group were selected. Immunohistochemical staining for ALDH1 marker was performed. In terms of evaluation of the ALDH1 expression, the percentage of stained cells as well as the intensity of cytoplasmic staining was considered. Results: In this study, the percentage of stained cells, the intensity of staining the epidermal cells, and the final score of the ALDH-1 expression were significantly different between two groups (P < 0.001). There was no significant relationship between ALDH-1 expressions and sex (P = 0.0202), and also, lesion location and final score (P = 0.345). No correlation was found between age and ALDH-1 expression (P = 0.217, r = 0.232). Conclusion: To sum up, ALDH1 was significantly expressed in CLP; furthermore, the expression may be correlated with malignant transformation. Consequently, ALDH1 might be an independent prognostic indicator in CLP. However, further studies with larger patient samples are required to verify the findings of the current study.