Twist promotes adhesion of WM164 cells to fibroblasts. Slug (siSlug) and Twist (siTwist) were silenced and expression levels compared to control siRNA (scRNA). (A) Silencing of Slug led to increased E-cadherin levels whereas silencing of Twist resulted in decreased N-cadherin and a slight increase of E-cadherin. (B) Silencing of Slug (p<0,01) and Twist (p<0,05) led to significantly increased adhesion to keratinocytes. (C) Twist but not Slug silencing resulted in decreased adhesion to fibroblasts. (D) Scratch assay showed a highly significant reduction in random migration after Slug and Twist silencing. Wound closure was significantly delayed in siTwist melanoma cells compared to siSlug cells. (E) A significant decrease in site-directed migration was observed after silencing of Slug and Twist. *, p<0.05 significant; **, p<0.01 highly significant. (F) Immunohistochemical analyses of Slug and Twist in paraffin-embedded sections of nevi, primary cutaneous melanoma and metastases for Twist and Slug. The immunoreactive score was obtained by multiplying the percentage of positive cells with staining intensity divided by 10.