Researchers from the California Institute of Technology, with support from the National Science Foundation (NSF), have developed conditional small RNA molecules that could treat cancer cells without causing negative side effects. 

Cancer is a personal disease that varies with each case and is based on one's own environmental and genetic factors. It is normally treated with chemotherapy, which consists of giving patients one or more types of drugs in hopes of this diagnosing and treating cancer cells. The problem with chemotherapy is that it is not selective enough, in that taking a drug which kills fast-growing tumor cells will also kill cells in the hair follicle, due to the fact that cells in the hair follicle are fast-growing as well. This is what leads to hair loss while going through chemotherapy treatments. 

But now, Niles Pierce, co-author of this study, along with his team, have created the conditional small RNA molecules to separate the diagnosis and treatment steps by utilizing characteristics found in our DNA and RNA. This will help target cancer cells only, and leave unaffected cells alone.

"The molecules are able to detect a mutation within a cancer cell, and then change conformation to activate a therapeutic response in the cancer cell, while remaining inactive in cells that lack the cancer mutation," said Pierce. 

RNA performs certain tasks in a cell, such as playing the messenger role and switching to communicate and watch over which genes are expressed in a cell "at any given time." By performing such tasks, RNA help to keep cells alive and healthy. 

Small RNAs, which are a particular class of RNAs, are what Pierce and his team are relying on for their new treatment. Small RNAs are less than 30 base pairs in length, where an average gene is thousands of base pairs long. In this study, two types of small RNAs are used because they are involved in many processes "that maintain life," and they structurally mimic small

RNA processes that naturally occur within our cells. The first small RNA opens up if there is a cancer mutation. If there is, a hidden signal is exposed within the small RNA. After it opens, the second small RNA attaches to it and triggers a chain reaction where RNA molecules continuously come together to form a longer chain. The longer the chain, the better because longer chains "trick" cells into thinking they're being attacked by a virus, and it causes cancer cells to self-destruct. 

"By decoupling diagnosis and treatment, we can create molecules that are both highly selective and highly effective in killing cancer cells," said Pierce. "Conceptually, small conditional RNAs have the potential to transform cancer treatment because they can change what we can expect from a molecule. Many years of work remain to establish whether this conceptual promise can be realized in human patients."

The study was published in Proceedings of the National Academy of Sciences.