Immunohistochemical overexpression of TWIST1 in metastatic melanomas compared with primary melanomas and nevi

Abstract

Melanoma is an aggressive neoplasia with poor prognosis when not identified and treated early. Phenotypic changes related to melanocytic cell invasion and metastasis have been associated with overexpression of the transcription factor TWIST1, which contributes to upregulation of epithelial-mesenchymal transition in melanoma. We aimed to evaluate the immunohistochemical expression of TWIST1 in nevi, primary melanomas and metastatic melanomas. This is a retrospective cross-sectional study of 71 histological samples with diagnosis of nevus, primary melanoma and metastatic melanoma. The immunohistochemical analysis was performed applying Twist1 ‘clone 2C1a’ monoclonal antibody and the results were interpreted according to scores of intensities and percentage of positive cells. There was TWIST1 nuclear overexpression in metastatic melanomas when compared to the primary melanomas and melanocytic nevi groups. There was minor significant difference regarding nuclear expression between primary melanomas and nevi.  In conclusion, the results of our evaluation of immunohistochemical expression can be consistent with the role of the TWIST1 in metastasis of melanomas.