UCSF researchers discovered that the oncogene Src can appear on the exterior of tumor cells via autophagolysosomal exocytosis, presenting an extracellular Src (eSrc) antigen that antibody therapeutics can target. In mouse studies, antibody constructs directed at eSrc—either as radioimmunoconjugates or immune‑recruiting agents—shrank tumors, suggesting a broad, previously hidden antigen class for solid‑tumor immunotherapies (Science). In parallel, Nature Biotechnology published a logic‑gated trispecific engager that amplifies macrophage‑mediated killing in solid tumors by directing macrophages and tumor cells while engaging immune checkpoints. Both advances expand the toolkit for targeting solid malignancies by leveraging tumor biology to expose therapeutic vulnerabilities.