Melittin's Antitumor Potential Unlocked by Exposure-Control Strategies, Mitigating Systemic Toxicity

Melittin, a key peptide from bee venom, demonstrates potent antitumor activity by disrupting cell membranes. However, its clinical translation is severely hampered by dose-limiting systemic side effects, including hemolysis, non-specific cytotoxicity, and immunogenic risk. Current therapeutic approaches struggle to deliver melittin effectively to tumor sites while sparing healthy tissues, creating a critical gap in harnessing its therapeutic potential without unacceptable systemic exposure.

This comprehensive review analyzed existing literature on melittin delivery and detoxification strategies, reframing its therapeutic translation as an exposure-control challenge. Researchers summarized five key detoxification-oriented approaches: nanocarrier shielding, tumor enrichment, activatable prodrugs, cell membrane-biomimetic systems, and nanosponge-based detoxification. The review synthesized these strategies into a novel three-layer framework designed to localize melittin's activity and minimize systemic toxicity, providing a roadmap for future development.

The review identified that uncontrolled systemic exposure is the primary barrier to melittin's clinical use, rather than a lack of lytic potency. It highlighted various strategies to mitigate this, including encapsulating melittin in nanocarriers for targeted delivery and developing prodrugs that activate only in the tumor microenvironment. Cell membrane-biomimetic systems and nanosponges were also discussed for their potential in shielding or detoxifying melittin. The authors proposed a three-layer framework for exposure control: systemic shielding, tumor enrichment, and conditional activation. This framework aims to precisely localize melittin's cytotoxic effects. Key translational priorities identified include establishing quantitative hemolysis thresholds, assessing serum leakage, evaluating repeat-dose immunogenicity, and ensuring manufacturing robustness. > Standardized exposure-control design, rather than further enhancement of lytic potency, is essential for advancing melittin toward antitumor therapy.