College of Arts and Sciences Investigators Awarded Patent for Cancer-Targeting RNA Molecules

Dr. Hua Shi

The patent, issued on January 6, 2015, describes the design and testing of novel molecules comprised of nucleic acids [RNA aptamers] that interact with specific sites present on cancer cells. The RNA aptamers are then able to target cancer cells for destruction via the patient’s own immune system. The patent was issued to the inventors of the process:

Dr. Hua Shi Associate Professor of Biology (pictured right)
Dr. Albert Millis Vincent J. O’Leary Professor of Biology
• Dr. Kimi Nishikawa Research Associate in Biology
• Dr. Prabhat Mallik, Research Associate in Biology

Importantly, these RNA aptamers are bifunctional meaning that they are able to bind two separate targets simultaneously. Specifically, these RNA aptamers bind to both the complement protein C3, which is normally present in blood plasma and a critical component of the innate immune system, and to the surface of cancer cells, causing the C3 to attach to the cell—a process referred to as opsonization. Subsequently, the patient’s own immune system, comprised in part of circulating phagocytic cells, can recognize the attached C3, attack and destroy the targeted cancer cells. Use of these aptamers to commandeer the process of opsonization is also described in the patent.

Importantly, this strategy can be applied to a virtually unlimited range of targeting aptamers to create a toolbox of therapeutic drugs. Previously designed aptamers and aptamers created to bind newly discovered targets can be incorporated into bifunctional constructs to induce aptamer-mediated opsonization of any disease-causing cells. Aptamer-mediated opsonization via C3 is a potential breakthrough immunotherapy that may enable development of a new class of safe and reliable therapeutic drugs.