A novel benzimidazole analogue inhibits the hypoxia-inducible factor (HIF)-1 pathway

Area of Science:

• Oncology
• Molecular Biology
• Drug Discovery

Background:

• Hypoxia-inducible factor (HIF)-1 is a key regulator in solid tumors and a therapeutic target.
• Developing novel HIF-1 inhibitors is crucial for effective cancer therapy.

Purpose of the Study:

• To identify and characterize a novel benzimidazole analogue, AC1-004, as a HIF inhibitor.
• To investigate the mechanism of action and in vivo efficacy of AC1-004.

Main Methods:

• Utilized an HRE-dependent cell-based assay in HCT-116 cells to screen for HIF inhibitors.
• Assessed AC1-004's effect on HIF-1alpha accumulation, target gene expression (VEGF, EPO), and angiogenesis in vitro.
• Investigated the Hsp90-Akt pathway's role in AC1-004-mediated HIF-1alpha degradation.
• Evaluated AC1-004's antitumor activity and side effects in vivo.

Main Results:

• AC1-004 inhibited hypoxia-induced HIF-1alpha accumulation in multiple cancer cell lines.
• AC1-004 down-regulated HIF-1 target genes (VEGF, EPO) and inhibited angiogenesis in vitro.
• AC1-004 induced HIF-1alpha degradation via the Hsp90-Akt pathway.
• AC1-004 significantly reduced tumor size by 58.6% in vivo without severe side effects.

Conclusions:

• AC1-004 is a novel benzimidazole analogue with potent HIF-1 inhibitory activity.
• AC1-004 targets HIF-1alpha stability through the Hsp90-Akt pathway.
• AC1-004 demonstrates significant in vivo antitumor efficacy and represents a promising lead compound for anticancer drug development.