Dual-modal tumor-selective Benzofuran tracer integrating real-time imaging and anticancer effects

Microtubule-targeting agents remain a cornerstone of cancer therapy; however, few compounds can simultaneously visualize intratumoral distribution and correlate pharmacodynamics with therapeutic response. Here, we describe BF-04, a Benzofuran-derived microtubule destabilizer that circumvents multidrug resistance and integrates anticancer efficacy with dual-modality imaging. Chemical conjugation with the Cyanine 5 fluorescent dye (Cy5) and Zirconium-89 (89Zr) provided high-contrast, real-time fluorescence and Positron Emission Tomography (PET) signals without the need for antibody or nanoparticle carriers, enabling direct monitoring of drug distribution and retention in tumors. Importantly, BF-04 exhibited tumor-selective accumulation independent of labeling, confirming a scaffold-driven targeting mechanism with strong translational potential for image-guided therapy. Mechanistically, BF-04 induced microtubule depolymerization, mitotic arrest, and apoptosis across multiple cancer cell lines and patient-derived organoids (PDOs). In vivo studies demonstrated selective tumor uptake and robust growth suppression with minimal systemic toxicity. Collectively, these findings establish BF-04 as a promising theranostic platform that combines potent microtubule disruption with real-time imaging to facilitate precision cancer therapy.