MiRNAs have been widely known to function as either oncogenes or tumor suppressors under certain conditions. The dysregulated miRNAs have been shown to affect the hallmarks of cancer, including sustaining proliferative signaling, eluding growth suppressors, resisting cell death, and inducing angiogenesis. An increasing number of studies have identified miRNAs as potential biomarkers for human cancer diagnosis, prognosis and therapeutic targets. Signosis has developed Cancer miRNA Array including 132 cancer-related miRNAs for cancer research.