The expression pattern of certain microRNAs, or miRNAs, may predict tumor aggressiveness in some patients with lung cancer, according to a new study by researchers at the National Cancer Institute, in collaboration with scientists at the Ohio State University Comprehensive Cancer Center, in Columbus; and Jikei University School of Medicine and the National Cancer Center Research Institute, both in Tokyo, Japan (Yanaihara N et al. Cancer Cell. 2006;9:189-198).
As these small segments of RNA are thought to control gene expression, they may play a role in changing the expression of cancer-related genes. To assess this, researchers examined 104 pairs of primary tumor tissue and corresponding noncancerous lung tissue from the same patients and used microarray analysis to study patterns of miRNA expression in each sample. Two miRNAs—has-mir-155 and has-let-7a-2—were identified as prognostic indicators in patients with lung adenocarcinomas. Specifically, high levels of has-mir-155 or low levels of has-let-7a-2 were associated with poor prognosis.
Hampton T. Lung Cancer and MicroRNAs. JAMA. 2006;295(16):1889. doi:10.1001/jama.295.16.1889-c