Immunohistochemical expression and localization of MMP-9, MMP-13, E-Cadherin and Ki-67 in road pavers' skin chronically exposed to bitumen products

To investigate the matrix metalloproteinase (MMP)-9, (MMP)-13, E-Cadherin and Ki-67 expressions in road pavers' skin chronically exposed to bitumen products in order to contribute to a better understanding of the earlier tissue alteration. Skin punch biopsies from 16 daily exposed workers and a control group were studied by immunohistochemistry. Morphometric and densitometric analyses were also conducted. Morphological specimen evaluation of skin of road pavers showed epidermal thinning, flattening and loss of intercellular junction with a decreased expression of E-cadherin confined to the basal skin layer, together with MMP-9 and MMP-13 overexpressions in all epidermis layers, vascular structures and adnexa. No immunohistochemical alteration was reported for Ki-67 vs normal skin. Results from this study show that overexpression of MMP-9 and MMP-13 may represent an early response of the first human barrier to exposure to bitumen products. Regulation of MMPs could be one of the strategies to prevent primary skin disease.