Small peptide inhibitor from the sequence of RUNX3 disrupts PAK1-RUNX3 interaction and abrogates its phosphorylation-dependent oncogenic function.

P21 Activated Kinase 1 (PAK1) is an oncogenic serine/threonine kinase known to play a significant role in the regulation of cytoskeleton and cell morphology. Runt-related transcription factor 3 (RUNX3) was initially known for its tumor suppressor function, but recent studies have reported the oncogenic role of RUNX3 in various cancers. Previous findings from our laboratory provided evidence that Threonine 209 phosphorylation of RUNX3 acts as a molecular switch in dictating the tissue-specific dualistic functions of RUNX3 for the first time.