Lance Ford

The let-7 microRNA reduces tumor growth in mouse models of lung cancer

MicroRNAs have been increasingly implicated in human cancer and interest has grown about the potential to use microRNAs to combat cancer. Lung cancer is the most prevalent form of cancer worldwide and lacks effective therapies. Here we have used both in vitro and in vivo approaches to show that the let-7 microRNA directly represses cancer growth in the lung. We find that let-7 inhibits the growth of multiple human lung cancer cell lines in culture, as well as the growth of lung cancer cell xenografts in immunodeficient mice. Using an established orthotopic mouse lung cancer model, we show that intranasal let-7 administration reduces tumor formation in vivo in the lungs of animals expressing a G12D activating mutation for the K-ras oncogene. These findings provide direct evidence that let-7 acts as a tumor suppressor gene in the lung and indicate that this miRNA may be useful as a novel therapeutic agent in lung cancer.

Applying small RNA molecules to the directed treatment of human diseases: realizing the potential

Small interfering RNAs (siRNA) and microRNAs (miRNA) are gaining considerable attention in the pharmaceutical and biotechnology industries, as research has revealed their likely clinical and agricultural applications. The capacity of siRNAs to dramatically and specifically reduce the expression of targeted genes has spawned multiple clinical trials to establish the therapeutic potential of small RNAs targeting viral, cancer and other disease-related genes. The successful application of siRNAs will enable the development of therapeutic applications based on miRNAs that have been observed to contribute to a variety of human diseases. This article reviews advances that have been made to apply small RNAs as therapeutics.