“Larger studies and extensive clinical validation will help to identify miRNAs that have true diagnostic value. From our experience and published reports, microRNA profiles have appeared to be more useful in terms of their diagnostic value than messenger RNA profiles. The fact that miRNAs are stable in FFPE (formalin-fixed paraffin embedded) tissue samples opens up a wider array of available diagnostic specimens for such validations. Poor stability of messenger RNA in FFPE samples and the ability to amplify it has been an issue for doing such kinds of transcriptomic studies. Being able to go back to older archived tissues from patients with known clinical outcomes obviously allows you to do the kinds of studies that are needed to validate the diagnostic and predictive value of a particular profile. Recent advances in technology for detection of microRNA have pushed the ability to detect levels from even a single cell so even samples with limited material are possible to evaluate now.”