As a master EMT-inducing transcription factor that plays essential role in tumor invasion, metastasis, and therapy resistance, ZEB1 can be degraded by ubiquitin ligase Siah1/2 and Skp1-Pam-Fbxo45 complex in an ubiquitination-proteasome-dependent manner, and stabilized by FLICE/caspase-8-associated huge protein (FLASH) and deubiquitinases USP5117,29. This evidence concerns the gene SIAH1 and neoplasm.