Homeobox protein (HOX)

Homeobox (HOX) proteins are a highly conserved family of 39 transcription factors in humans that act as master regulators of embryonic development, specifically orchestrating the patterning of the body axis and organogenesis. These proteins contain a characteristic 60-amino acid DNA-binding homeodomain and typically require cofactors from the TALE family, such as PBX, to achieve high binding specificity and functional diversity. While their expression is largely silenced after birth, HOX proteins are frequently reactivated or dysregulated in a wide range of cancers, including acute myeloid leukemia, glioblastoma, and various solid tumors, where they promote cell survival, invasion, and resistance to therapy. Because HOX proteins are notoriously difficult to target directly with small molecules, current therapeutic approaches focus on disrupting their interaction with cofactors or inhibiting upstream epigenetic regulators like the MLL-Menin complex that drive their overexpression. Experimental peptides such as HXR9 and HTL-001 have demonstrated the potential to induce apoptosis in cancer cells by blocking the HOX-PBX interface, marking the HOX family as a significant emerging target in precision oncology.

Other names

HOX transcription factorHomeodomain proteinAntennapedia-like protein

Competitive inhibition of HOX-PBX protein-protein interaction; Downregulation of HOX gene expression via MLL-Menin complex inhibition.