MicroRNA expression profiling in FFPE samples
MicroRNAs are not significantly affected by the formalin fixation process used in preparing Formalin-Fixed, Paraffin-Embedded (FFPE) tissue samples. To exploit the opportunity of using archived samples to detect changes in miRNA expression levels in various disease states, we offer microRNA profiling from archived FFPE tissue samples. We isolate total RNA from as little as 8 sections (20 microns each) using Ambion's Recover all Total Nucleic Acid Isolation Kit, and enrich the low molecular weight RNA in the samples. Samples are then labeled using Genisphere's Flash Tag RNA Labeling Kit and hybridized to ORB mirBASE 16 multispecies microarrays (Human, Mouse or Rat). The resulting FFPE microRNA expression profiles correlates well with that of microRNA expression profiles from fresh tissues.