ZEB1 and Kaposi's sarcoma: This is further supported by the observation that activation of the Notch-induced transcription factors Slug and zinc finger E-box-binding homeobox 1 after KSHV infection contributes to the endothelial-to-mesenchymal transition (EndMT) that is important for the malignant progression of infected endothelial cells independently from TGF-beta signaling,124 which regulates EndMT in non-malignant ECs.125 In vitro Notch inhibition with gamma-secretase inhibitors in KS-like cell lines induces mitotic catastrophe,126 suggesting that targeting Notch may be effective for KS.