Spatially resolved and multiplexed MicroRNA quantification from tissue using nanoliter well arrays.

Spatially resolved gene expression patterns are emerging as a key component of medical studies, including companion diagnostics, but technologies for quantification and multiplexing are limited. We present a method to perform spatially resolved and multiplexed microRNA (miRNA) measurements from formalin-fixed, paraffin-embedded (FFPE) tissue. Using nanoliter well arrays to pixelate the tissue section and photopatterned hydrogels to quantify miRNA, we identified differentially expressed miRNAs in tumors from a genetically engineered mouse model for non-small cell lung cancer (K-rasLSL-G12D/+; p53fl/fl). This technology could be used to quantify heterogeneities in tissue samples and lead to informed, biomarker-based diagnostics. MicroRNA is a short, noncoding RNA molecule that regulates many biological processes and is emerging as a biomarker; a method has been developed to perform spatially resolved, measurements of multiple microRNA directly from formalin-fixed, paraffin-embedded (FFPE) tissue. Spatially resolved gene expression patterns are becoming a key area in medical studies, including diagnostics, but technologies for quantification and multiplexing in this area have been limited. Using a mouse model, a team headed by Patrick S. Doyle at the Massachusetts Institute of Technology, USA has succeeded in developing a method based on nanoliter well arrays for microRNA quantification. The team demonstrated that its technology allows greater multiplexing and better special resolution than can be achieved with existing methods. The authors consider that their technology has excellent potential for quantifying heterogeneities in FFPE tissue for next-generation biomarkers.