VGLL4 (vestigial like family member 4) functions as a critical transcriptional repressor that negatively regulates the Hippo-YAP signaling pathway by competing with YAP/TAZ for binding to TEAD transcription factors 123. The protein acts as a tumor suppressor, with diminished VGLL4 expression correlating with shorter survival in breast cancer patients 2. Mechanistically, VGLL4 occupies TEAD proteins to prevent oncogenic YAP binding, thereby inhibiting YAP-dependent gene transcription and tumorigenic phenotypes 12. VGLL4 protein stability is regulated through nuclear ubiquitination by UBR5 E3 ligase at Lys61, which targets VGLL4 for degradation and permits YAP signaling during liver development and tumorigenesis 1. Additionally, VGLL4 forms repressive transcriptional condensates with TEAD4 under cellular stress conditions, leading to DNA aggregation and gene expression inhibition 4. Beyond cancer regulation, VGLL4 promotes vascular endothelial cell specification through TEAD1 interactions 5 and maintains extracellular matrix homeostasis in cartilage through a VGLL4-TEAD-SMAD3 complex, with deficiency leading to osteoarthritis 6. These findings establish VGLL4 as a multifunctional regulator with therapeutic potential in cancer and degenerative diseases.