Pre-B-cell leukemia transcription factor 1 (PBX1)

Pre-B-cell leukemia transcription factor 1 (PBX1) is a nuclear protein member of the TALE (three amino acid loop extension) class of homeodomain-containing transcription factors. PBX1 forms heterodimers with HOX proteins and other transcription factors (e.g., MEIS, PREP) to regulate gene expression, particularly during embryonic development and organogenesis. In adults, PBX1 is implicated in tissue homeostasis, hematopoiesis, and immune function. PBX1 has a well-established role in oncogenesis; aberrant PBX1 activity, often in complex with HOX partners, contributes to acute lymphoblastic leukemia and a range of solid tumors. While not a classical drug target, PBX1 is currently being explored as a molecular target for inhibitors in cancer and possibly autoimmune disease due to its roles in cell fate determination and proliferation.

Other names

PBX homeobox 1PBX1Pre-B-cell leukemia transcription factor 1TALE homeodomain proteinextradenticle homolog (in Drosophila)

Future therapeutic strategies involve disruption of the PBX1/HOX protein–protein interaction to block oncogenic transcriptional activity in cancer cells.