VCU Massey Cancer Center researchers have discovered why a molecule expressed with a protein known to drive 20 percent of breast cancers can lead to decreased effectiveness of a well-known targeted therapy.
They found that a molecule called microRNA-4728 prevents therapies targeting the HER2 protein from being effective. MicroRNA-4728 is co-expressed with HER2 in certain types of breast cancer cells, which means that when HER2 is overexpressed, so is microRNA-4728. Expression refers to the level of proteins in cells.
These targeted therapies, HER2 inhibitors, are currently administered with chemotherapies to boost effectivity, but chemotherapies can be extremely toxic to noncancerous, normal cells, said Anthony Faber, Ph.D., assistant professor in the Philips Institute for Oral Health Research in the VCU School of Dentistry and a member of the Developmental Therapeutics research program at Massey Cancer Center.
The finding could lead to more effective combination therapies that inhibit the overexpression of HER2 and are relatively nontoxic, Faber said.