αEβ7 Expression Increases With the Extent of Cutaneous Involvement in Mycosis Fungoides.

Abstract

Cell adhesion molecules are essential to lymphocyte migration in neoplastic and inflammatory skin diseases. Our aim was to investigate possible differences in cell adhesion molecule expression between mycosis fungoides (MF) and inflammatory skin diseases (drug reactions and allergic contact dermatitis). We selected 33 biopsies from patients with MF and 10 biopsies of patients with inflammatory skin diseases from Department of Pathology-Universidade Federal de São Paulo (UNIFESP) from January 1997 to December 2013. Expression of α4β1 integrin and αEβ7 integrin was assessed by immunohistochemistry in intraepidermal lymphocytes by counting 4 microscopic epidermal fields (×400) and comparing those between the 2 groups. We observed increased expression of integrin αEβ7 in intraepidermal lymphocytes in advanced stages of MF (T3 and T4). αEβ7 expression was detected in intraepidermal dendritic cells of MF and inflammatory diseases samples. The expression of E-cadherin in epidermal cells in MF outlined Pautrier microabscesses, whereas in inflammatory diseases, spongiosis reduced its expression in keratinocytes. The findings presented here support the idea that the lymphocyte migratory mechanism observed in neoplasms is similar to that of inflammatory processes of the skin.