Inhibitor of DNA binding 1 (ID1)

Inhibitor of DNA binding 1 (ID1) is a member of the ID protein family, which are helix-loop-helix (HLH) transcription regulators lacking a DNA-binding domain. ID1 acts as a dominant-negative antagonist of basic HLH transcription factors by forming non-functional heterodimers, blocking their ability to bind DNA and regulate gene expression. This regulatory role governs fundamental cellular processes such as differentiation, proliferation, migration, and angiogenesis. ID1 is highly expressed in embryonic and cancer stem cells but downregulated in differentiated adult tissues, making it an attractive therapeutic target in oncology. Overexpression or dysregulation of ID1 is implicated in a variety of cancers, where it promotes tumor growth, metastasis, angiogenesis, maintenance of stemness, and chemoresistance. Suppressing ID1 function has been shown to reduce cancer aggressiveness and restore sensitivity to chemotherapy in preclinical models, though no direct ID1 inhibitors have attained clinical approval. ID1 is also used as a biomarker for aggressive disease, cancer stem cell populations, and angiogenic endothelial progenitors[1][2][4][5][8].

Other names

DNA-binding protein inhibitor ID-1BHLHB24bHLHb24dJ857M17.1.2Class B basic helix-loop-helix protein 24Inhibitor of differentiation 1

Inhibition or knockdown of ID1 increases cancer cell sensitivity to chemotherapy by reducing chemoresistance and promoting apoptosis[1][8] Targeting ID1 may impair tumor angiogenesis by blocking VEGF-induced pathways[1] Cannabidiol may exert anti-tumor effects by inhibiting ID1 activity[2] Downregulation of ID1 can promote differentiation, reduce stemness, and decrease tumorigenicity in various cancers[1][8]