Genome-wide identification of bone metastasis-related microRNAs in lung adenocarcinoma by high-throughput sequencing

MicroRNAs (MiRNAs) are a class of small noncoding RNAs of about 18-23 nt in length. They can regulate the processing and translation of mRNAs through base pairing with mRNAs'' 3''-untranslated regions (3''-UTRs). miRNAs are widely involved in critical biological processes, such as embryonic development, cell division, differentiation, and apoptosis. Recent evidence has indicated that deregulation of microRNAs is tightly associated with the development of lung cancer. In this project, to understand the roles of microRNAs in the bone metastasis of lung adenocarcinoma, we constructed two small RNA libraries from patients of lung adenocarcinoma with and without bone metastasis. High-throughput sequencing combined by differential expression analysis. A sum of 28 miRNAs was identified to be differentially expressed, including 21 up-regulated and 7 down-regulated miRNAs. In addition, we predicted the targets of the differentially expressed miRNAs. Functional annotation of targets of metastasis-related miRNAs indicated that signaling pathways involved in many fundamental biological processes was linked to the bone metastasis of lung cancer, for example, MAPK signaling, Wnt signaling, NF-KappaB signaling etc. The data of this project provide mechanistic insights and suggest the potential for the utility of miRNA-based drugs as novel therapeutic strategies in preventing metastasis of lung cancer.