Pre-B-cell leukemia homeobox interacting protein 1 (PBXIP1)

Pre-B-cell leukemia homeobox interacting protein 1 (PBXIP1, also known as HPIP) is a multi-functional transcriptional corepressor and microtubule-binding protein that interacts with pre-B-cell leukemia homeobox transcription factors (such as PBX1, PBX2, PBX3) and inhibits their ability to activate transcription by blocking DNA binding of PBX-HOX complexes[1][2][3]. It is primarily cytoplasmic, though it can shuttle to the nucleus, and also tethers estrogen receptor-alpha (ESR1) to microtubules, affecting nuclear signaling by estrogen receptors[1][6]. PBXIP1 is implicated in the regulation of cancer cell growth, migration, and survival, particularly in breast cancer, glioma, astrocytoma, ependymoma, and leukemia[1][4][5]. It contributes to cell proliferation, cytoskeletal remodeling, and hematopoietic differentiation, in part via activation of the PI3K/AKT signaling pathway in erythroid and progenitor cells[2][4]. PBXIP1 overexpression is associated with tumor aggressiveness and may represent a novel therapeutic target and biomarker in relevant cancers, though no specific targeted drugs are currently available[4][5][6].

Other names

HPIPHematopoietic PBX-interacting proteinPre-B-cell leukemia transcription factor-interacting protein 1Pre-B-cell leukemia homeobox interacting protein 1PBX-interacting protein 1

Not established for any approved or investigational drugs; no direct targeting molecules identified currently \n- Potential mechanisms may involve inhibition of protein-protein interactions (PBXIP1:PBX1), modulation of downstream transcriptional programs, and impact on cytoskeletal regulation