How can we turn off the genes that promote the development of cancer? Using specially designed nanoparticles as genetic patches, engineers can deliver customized payloads to a cell&#039;s gel-like cytoplasm where most cellular activity occurs, and mitigate the effects of cancer-causing genes in the cell&#039;s nucleus. This image shows nanoparticles (red) in the cytoplasm of cervical tumor cells (green). Credit: Omar F. Khan, Edmond W. Zaia. 