4/30/2010 PERMALINK
Study links microRNA to shut-down of DNA-repair genes. New research shows for the first time that molecules called microRNA can silence genes that protect the genome from cancer-causing mutations. The study, led by researchers at the Ohio State University Comprehensive Cancer Center-Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, shows that microRNA-155 (miR-155) can inhibit the activity of genes that normally correct the damage when the wrong bases are paired in DNA. The loss or silencing of these genes, which are called mismatch repair genes, causes inherited cancer-susceptibility syndromes and contributes to the progression of cancers. "This is the first evidence that deregulation of microRNAs can cause genomic instability, a characteristic of cancer cells," said principal investigator Dr. Carlo M. Croce, director of Ohio State's Human Cancer Genetics program.