Cancer can be persistent and difficult to treat effectively, but cancer researchers can be just as persistent and difficult. João Conde and Natalie Artzi of Massachusetts Institute of Technology and coworkers have set an example in developing a nanoparticle-containing hydrogel patch that shows promising efficacy against colorectal cancer by attacking tumors in multiple ways (Nat. Mater. 2016, DOI: 10.1038/nmat4707 ).When implanted at tumor sites in mice, the patch delivers several treatments as the gel breaks down over time. Gold nanospheres in the patch carry two components: siRNAs that turn off KRas, which is an oncogene that makes cells cancerous, and a cytoplasm-localizing peptide that helps optimize siRNA activity. Gold nanorods in the patch carry the antibody drug Avastin, which blocks cancer cell growth. The nanorods also generate tumor-damaging heat when a phototherapy probe shines near-infrared light on them. Both the nanospheres and nanorods include a tumor-localizing peptide and a fluorescent group for imaging the nanoparticles. In the mice, the patch eradicated tumors completely. And when administered after surgical tumor removal, the patch prevented cancer recurrence. “Future studies will focus on utilizing colonoscopy equipment to deliver our therapeutic platform in a minimally invasive manner,” Artzi says.