Transcription factor HES1 (HES1)

Transcription factor HES1 (Hairy and enhancer of split 1) is a basic helix-loop-helix (bHLH) protein that serves as a primary downstream effector of the Notch signaling pathway. It plays a critical role in developmental processes and adult tissue homeostasis by regulating the balance between cell proliferation and differentiation, especially in neural, hematopoietic, and gastrointestinal systems. HES1 functions mainly as a transcriptional repressor, binding to specific DNA sequences such as the N-box and recruiting co-repressors like TLE/Groucho and histone deacetylases (HDACs) to silence genes that would otherwise promote differentiation. In various human malignancies, including T-cell acute lymphoblastic leukemia and pancreatic cancer, HES1 is aberrantly overexpressed, contributing to tumor survival, the maintenance of cancer stem cells, and resistance to chemotherapy. Therapeutic targeting of HES1 is being explored through direct small-molecule inhibitors like JI051 and repurposed drugs such as perhexiline, which antagonizes HES1-associated transcriptional signatures. However, because HES1 is vital for normal stem cell function and tissue regeneration, its pharmacological modulation presents significant safety challenges and therapeutic risks.

Other names

Hairy and enhancer of split 1HES-1HRYhHLbHLHb39Hes family bHLH transcription factor 1

Transcription repression through DNA binding to N-box and E-box motifs and recruitment of corepressor complexes (TLE/Groucho/HDAC)