We don't yet know how to kill the common cold—we can only suppress it. But we might be able to use the ever-changing virus to kill something else we've been unable to destroy: cancer.
According to researchers at the Salk Institute, the common cold has the ability to prevent cells from killing themselves when infected by a virus, causing them to spread through the body and generate the physical symptoms we've all come to know and despise. These scientists learned how to disable the E4-ORF3 protein responsible for preventing the self-destruct mechanism. As it turns out, part of E4-ORF3's process involves disabling the p53 protein, which itself works to suppress cancerous tumours.
What these scientists hope to do is create a modified version of the virus which seeks out cells that have had their p53 protein inhibited, and destroy those cells. Eurekalert writes:
The Salk findings may help scientists develop small molecules——the basis for the vast majority of current drugs——capable of destroying tumors by binding and disrupting large and complex cellular components that allow cancer cells to grow and spread. Understanding how viruses overcome healthy cells may also help scientists engineer tumor-busting viruses, which offer a new and potentially self-perpetuating cancer therapy. Such modified viruses would destroy only cancer cells, because they could only replicate in cells in which the p53 tumor suppressor has been deactivated. When a cancer cell is destroyed it would release additional copies of the engineered viruses, which would seek out and kill remaining cancer cells that have spread throughout the body.