title: Multiplex quantitative measurement of mRNAs from fixed tissue microarray sections.
abstract: The development of prognostic and diagnostic biomarkers, such as those from gene expression studies, requires independent validation in clinical specimens. Immunohistochemical analysis on tissue microarrays (TMAs) of formalin-fixed paraffin-embedded tissue is often used to increase the statistical power, and it is used more often than in situ hybridization, which can be technically limiting. Herein, we introduce a method for performing quantitative gene expression analysis across a TMA using an adaptation of 2D-RT-qPCR, a recently developed technology for measuring transcript levels in a histologic section while maintaining 2-dimensional positional information of the tissue sample. As a demonstration of utility, a TMA with tumor and normal human prostate samples was used to validate expression profiles from previous array-based gene discovery studies of prostate cancer. The results show that 2D-RT-qPCR expands the utility of TMAs to include sensitive and accurate gene expression measurements.
authors.affiliation: *Pathogenetics Unit ‡Tissue Array Research Program, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda †Fischell Department of Bioengineering and the Institute for Systems Research §Department of Mechanical Engineering, University of Maryland, College Park, MD.
authors.forename: Michael
authors.initials: M
authors.lastname: Armani
authors.forename: Michael
authors.initials: M
authors.lastname: Tangrea
authors.forename: Brian
authors.initials: B
authors.lastname: Yang
authors.forename: Alex
authors.initials: A
authors.lastname: Rosenberg
authors.forename: Kris
authors.initials: K
authors.lastname: Ylaya
authors.forename: Jennifer
authors.initials: J
authors.lastname: Morris
authors.forename: Jaime
authors.initials: J
authors.lastname: Rodriguez-Canales
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Hanson
authors.forename: Benjamin
authors.initials: B
authors.lastname: Shapiro
authors.forename: Michael R
authors.initials: MR
authors.lastname: Emmert-Buck
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Smela
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Hewitt
mesh_terms: D005240:Feasibility Studies; D020869:Gene Expression Profiling / Q000379:methods*; D057166:High-Throughput Screening Assays; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D016612:Paraffin Embedding; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000235:genetics* / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis*; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D046888:Tissue Array Analysis
chemical_list: D012333:RNA, Messenger