By administering a specific miRNA molecule that is reduced in hepatocellular carcinoma (HCC), scientists have halted the progression of liver tumors in mice. The results demonstrate for the first time that therapeutic delivery of a miRNA in an animal can result in tumor suppression, without the need for specifically targeting the cancer-causing oncogene. "This concept of replacing microRNAs that are expressed in high levels in normal tissues, but lost in diseases hasn't been explored before," said Dr. Joshua Mendell, senior author of the study. "Our work raises the possibility of a more general therapeutic approach that is based on restoring microRNAs to diseased tissues." HCC, which is the third leading cause of cancer deaths, expresses a reduced number of miRNAs, including miR-26a. By combining miRNA technology developed at Johns Hopkins, with the gene delivery expertise at Nationwide Children's Hospital, the reporting researchers were able to successfully deliver a recombinant adeno-associated virus (AAV) carrying miR-26a in a mouse model of HCC. This gene therapy strategy inhibited growth of cancer cells and led to tumor reduction and cell death, without causing toxic side effects to the remainder of the liver. The research team was made up of collaborators from Johns Hopkins, Nationwide Children’s Hospital, and Ohio State University. This work was published in the June 12 issue of Cell. [Press release 1] [Press release 2] [Cell abstract] Login Or Register To Read Full Story