Nanogalvanic Cells Release Highly Reactive Electrons in Tumors to Effectively Eliminate Tumors

Tumor microenvironment-activated Zn//MnO2 battery for sustained and local electrochemical immunotherapy

Metal ions are widely adopted to potentiate oxidative damage-induced immunogenic cell death (ICD) and regulate immune pathways. However, current ion delivery platforms lack precise administration over distribution and retention time within the tumor microenvironment, leading to high systemic toxicity and suboptimal therapeutic efficacy. Here, local electrochemical immunotherapy is developed by implanting a tumor microenvironment-activated Zn//MnO2 battery, which uses body fluid as an electrolyte and endogenous glutathione as a redox mediator to promote sustained generation and localized retention of electrochemical products (Zn2+ and Mn2+). These elements trigger the ICD effect through reactive oxygen species accumulation and stimulate the STING pathway to activate immune cells effectively. Strategic placement of this battery around subcutaneous tumor sites results in a 99.6% growth inhibition rate after a 14-day treatment. This work demonstrates a powerful electrochemical tool for drug-free cancer immunotherapy, which may open an avenue for sustained and localized delivery of immune agonists.

Targeting phosphatidylserine in tumor cell membranes with a zinc-containing molecule to efficiently combat tumor metastasis

Metal drugs, such as platinum drugs, are widely used in tumor treatment. However, most traditional tumor treatments face the risk of failure due to the ineffective control over drug resistance and tumor metastasis. Targeting the cell membrane and disrupting its function to combat drug resistance and metastasis is a promising strategy. Nevertheless, membranolytic drugs always cause significant cytotoxicity. In this study, we developed a zinc-containing molecule to selectively kill tumor cells by targeting phosphatidylserine in the tumor cell membrane, which is commonly distributed in the outer cell membrane of tumor cells. Herein, a structurally optimized amphiphilic zinc-containing molecule, 2aZn, was developed by screening the appropriate hydrophobic tail and linker. This functional molecule can disrupt the tumor cell membrane to kill various types of tumor cells with minimal damage to normal tissue. After repeated stimulation, no obvious drug resistance was observed. Importantly, 2aZn could successfully combat tumor metastasis by destroying the cell membrane and reducing the capacity of cells to invade. As a result, zinc-containing molecules have the potential to overcome drug resistance and tumor metastasis in the treatment of tumors, providing a new perspective for the design of effective antitumour medications.