Engineering a 660 nm-Responsive Optogenetic Inducer of Pyroptosis for Precision Cancer Therapy.

Inducing tumor cell pyroptosis represents a promising anticancer strategy; however, uncontrolled pyroptosis not only restricts the production of viral delivery vectors but also poses a risk of systemic damage, thereby limiting the translational application of pyroptosis-based therapies. The development of genetic tools that enable precise spatiotemporal control over pyroptosis remains challenging. To address this, we developed PyroRACS, a bioorthogonal optogenetic inducer for precise pyroptosis induction. PyroRACS utilizes an engineered red-light-activatable Cre-ON genetic switch (RACS) to drive the expression of the gasdermin D N-terminal domain, enabling tunable initiation of pyroptosis without relying on endogenous signaling pathways. We validated robust pyroptosis induction by PyroRACS in multiple cell lines. PyroRACS exhibited high controllability by selectively ablating cancer cells in vitro with precise spatiotemporal resolution. Moreover, its superior controllability enabled the production of the adenovirus vector and allowed "all-in-one" delivery of PyroRACS. In a tumor-bearing mouse model, spatially restricted induction of pyroptosis by PyroRACS resulted in effective tumor suppression, with no detectable systemic toxicity observed under the tested conditions. Collectively, PyroRACS provides a novel optogenetic tool for precise manipulation of pyroptosis, facilitating fundamental research and advancing pyroptosis-based precision oncology therapeutics.