Alternative tissue fixation for combined histopathological and molecular analysis in a clinically representative setting

Meecham, A. et al. (2021) Alternative tissue fixation for combined histopathological and molecular analysis in a clinically representative setting. Histochemistry and Cell Biology, 156(6), pp. 595-607. (doi: 10.1007/s00418-021-02029-1) (PMID:34905068) (PMCID:PMC8695534)

Abstract

Formalin is the principal tissue fixative used worldwide for clinical and research purposes. Despite optimal preservation of morphology, its preservation of DNA and RNA is poor. As clinical diagnostics increasingly incorporates molecular-based analysis, the requirement for maintaining nucleic acid quality is of increasing importance. Here we assess an alternative non-formalin-based tissue fixation method, PAXgene Tissue system, with the aim of better preserving nucleic acids, while maintaining the quality of the tissue to be used for vital existing diagnostic techniques. In this study, these criteria are assessed in a clinically representative setting. In total, 203 paired PAXgene Tissue and formalin-fixed samples were obtained. Blind-scored haematoxylin and eosin (H&E) sections showed comparable and acceptable staining. Immunohistochemistry (IHC) staining was suboptimal using existing protocols but improved with minor method adjustment and optimisation. Quality of DNA and RNA was significantly improved by PAXgene tissue fixation [RIN 2.8 versus 3.8 (p < 0.01), DIN 5.68 versus 6.77 (p < 0.001)], which translated into improved performance on qPCR assay. These results demonstrate the potential of PAXgene Tissue to be used routinely in place of formalin, maintaining adequate histological staining and significantly improving the preservation of biological molecules in the genomic era.

• Item Type: Articles
• Additional Information: This work was funded by Innovate UK (grant ref. 38618‐281179) and performed as part of the STRATFix consortium.
• Keywords: Formalin, DNA, RNA, PAXgene, fixative, FFPE.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Morris, Dr Hayley and Oien, Professor Karin
• Authors: Meecham, A., Miranda, E., Morris, H. T., Hair, J., Oien, K. A., Gerrard, G., Guppy, N., Mooney, D., Shaw, E. C., Ashton-Key, M., Lees, R., Flanagan, A., and Rodriguez-Justo, M.
• College/School: College of Medical Veterinary and Life Sciences > School of Cancer Sciences
• Journal Name: Histochemistry and Cell Biology
• Publisher: Springer
• ISSN: 0948-6143
• ISSN (Online): 1432-119X
• Published Online: 14 December 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Histochemistry and Cell Biology 156(6): 595-607
• Publisher Policy: Reproduced under a Creative Commons License