Inhibition of colorectal cancer progression through conformation-specific targeting of ADAM10 metalloprotease.

Introduction: Colorectal cancer (CRC) is the second leading cause of cancer-related deaths worldwide. Current first- and second-line therapies rely on oxaliplatin- or irinotecan-based combination chemotherapies combined with antibody-mediated inhibition of EGFR- or VEGF-dependent signaling, but these regimens are associated with significant side effects that limit long-term use and effectiveness. ADAM10 has emerged as a potential therapeutic target in CRC due to its role in activating oncogenic pathways such as Notch and EGFR; however, prior approaches targeting ADAM10 showed high toxicity. ADAM10 exists in an open, active conformation and a closed, auto-inhibited conformation, with the active form being more prevalent in tumor cells, providing a rationale for conformation-specific targeting. Methods: To investigate the therapeutic potential of 1H5, cellular viability was assessed using viability assays, and ADAM10 dependency was evaluated by shRNA-mediated knockdown. Modulation of oncogenic signaling pathways and target gene expression was validated by Western blotting and RT-qPCR, while transcriptomic changes were analyzed by bulk RNA sequencing. The effects of 1H5 on cell migration and invasion were assessed using wound-healing and transwell invasion assays, and therapeutic efficacy was evaluated in vivo using xenograft and syngeneic mouse models. Results: We show that 1H5 inhibits Notch and EGFR signaling and reduces proliferation of human CRC cell lines. We also found that 1H5 inhibits Wnt/β-catenin signaling in CRC cells and reduces their migration and invasion capacity. Finally, treatment studies in CRC cell line-derived xenograft models revealed marked antitumorigenic properties of 1H5. Discussion: Together, these findings demonstrate that selective targeting of the active conformation of ADAM10 enables simultaneous inhibition of multiple oncogenic pathways involved in CRC growth and progression and represents a promising therapeutic strategy warranting further clinical evaluation.