Pig-semen–derived exosome eye drops halt retinal tumors in mice

A Science Advances study reports eye drops made from pig-semen–derived exosomes carrying a nanozyme cancer-killing system can cross the retinal barrier to target retinoblastoma tumors in mice, halting tumor growth and preserving vision; the approach uses folic-acid tagging to improve selectivity and could inform drug delivery across other hard-to-penetrate barriers, though it is currently at early, animal-tested stages.