RT Journal Article
SR Electronic
T1 Tissues from routine pathology archives are suitable for microRNA analyses by quantitative PCR
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 84
OP 88
DO 10.1136/jcp.2008.058339
VO 62
IS 1
A1 U Siebolts
A1 H Varnholt
A1 U Drebber
A1 H-P Dienes
A1 C Wickenhauser
A1 M Odenthal
YR 2009
UL http://jcp.bmj.com/content/62/1/84.abstract
AB Background: MicroRNAs have recently taken centre stage as short non-coding RNAs that regulate mRNA expression.Aim/Methods: To assess the feasibility of using microRNA techniques on routinely processed tissues, the accessibility of two representative microRNAs was examined by real-time quantitative PCR in 86 human formalin-fixed paraffin-embedded (FFPE) samples from liver, breast, bone marrow, lymphatic tissues and colon. Murine liver was used to analyse the influence of fixation time and different fixatives.Results: High-quality microRNA was successfully extracted from routinely processed formalin-fixed tissues, resembling PCR amplification results from snap-frozen material analysed in parallel. While fixation time did not affect microRNA accessibility, non-buffered formalin or fixative supplements such as glutaraldehyde influenced PCR results. Storage of human tissues for up to 7 years did not cause a significant deterioration of microRNA. However, microRNA quality in human archival material following routine processing 10–20 years ago was decreased. Oxidation by ambient air during storage and fixation in non-buffered formalin is a possible reason for loss of microRNA quality.Conclusion: The assessment of microRNAs in readily obtained formalin-fixed paraffin-embedded samples is a highly promising tool in molecular pathology when similarly treated samples are analysed. Therefore, microRNA analyses will gain wider acceptance as an adjunct to morphological tissue assessment in routine pathology and retrospective studies.