Researchers unveiled an intelligent design framework for adeno‑associated virus (AAV) vectors that dynamically respond to the tumor microenvironment (TME). The approach modifies vector properties so expression or tropism changes in situ, aiming to improve tumor selectivity and reduce off‑target effects. The paper details engineered sensing elements and regulatory circuits embedded in AAV capsids or payloads to trigger activity only within defined TME conditions. Authors report improved tumor infiltration and reduced systemic exposure in preclinical models. If reproducible, the design could address longstanding delivery hurdles for viral gene therapies in solid tumors and alter how companies prioritize AAV engineering for oncology applications.