LCM assisted biomarker discovery from archival neoplastic gastrointestinal tissues

Expression array analysis of epithelial mRNA to identify biomarkers of premalignant and malignant conditions in the gastrointestinal (GI) tract is an area of intense study. Archived formalin-fixed paraffin-embedded (FFPE) tissues documenting these changes are readily available and should be a valuable resource for retrospective analysis. Laser capture microdissection of defined areas of epithelial cells at different stages of neoplastic progression is described together with methods for prequalification of RNA in FFPE tissue blocks selected for analysis. Paradise reagents specifically designed for isolation and amplification of RNA from FFPE archival tissue specimens are used to prepare probes for the human X3P microarray from Affymetrix.