Transcription factor HES5 (HES5)

Transcription factor HES5 (Hairy and enhancer of split 5) is a basic helix-loop-helix (bHLH) protein that serves as a primary downstream effector of the Notch signaling pathway [UniProt: Q5TA89]. It functions as a transcriptional repressor, typically binding to N-box sequences in the promoters of proneural genes to inhibit their expression and maintain stem cells in an undifferentiated state [NCBI Gene: 388585]. In the central nervous system, HES5 plays a critical role in regulating the balance between neural stem cell self-renewal and differentiation into neurons or glia [PubMed: 17629545]. Dysregulation of HES5 is frequently observed in various malignancies, including glioblastoma and medulloblastoma, where its overexpression promotes tumor cell stemness and resistance to therapy [PubMed: 31213565]. While small molecule inhibitors directly targeting HES5 are challenging to develop due to its nature as a transcription factor, HES5 mRNA represents a viable therapeutic target for RNA-based modalities like siRNA or antisense oligonucleotides [PubMed: 28671665]. By reducing HES5 levels, these therapies aim to induce differentiation in cancer stem cells or restore normal developmental programs [PubMed: 25661153].

Other names

Hairy and enhancer of split 5bHLHb38Class B basic helix-loop-helix protein 38HES-5

RNA interference (siRNA) or antisense oligonucleotides (ASO) targeting HES5 mRNA to prevent translation of the HES5 repressor protein, thereby promoting cellular differentiation.