protocol-for-her2-fish-using-non-cross-linking-formalin-free-tissue

Protocol for HER2 FISH Using a Non-cross-linking, Formalin-free Tissue Fixative to Combine Advantages of Cryo-preservation and Formalin Fixation

Morphologic assessment of formalin-fixed, paraffin-embedded (FFPE) tissue samples has been the gold standard for cancer diagnostics for decades due to its ...

Medical University Graz

Requirements on tissue fixatives are getting more demanding as molecular analysis becomes increasingly relevant for routine diagnostics. Buffered formaldehyde in pathology laboratories for tissue fixation is known to cause chemical modifications of biomolecules which affect molecular testing. A novel non-crosslinking tissue preservation technology, PAXgene Tissue (PAXgene), was developed to preserve the integrity of nucleic acids in a comparable way to cryopreservation and also to preserve morphological features comparable to those of formalin fixed samples.

Pathogen Inactivating Properties and Increased Sensitivity in Molecular Diagnostics by PAXgene, a Novel Non-Crosslinking Tissue Fixative.

Molecular diagnostics in personalized medicine increasingly relies on the combination of a variety of analytical technologies to characterize individual diseases and to select patients for targeted therapies. The gold standard for tissue-based diagnostics is fixation in formalin and embedding in paraffin, which results in excellent preservation of morphology but negatively impacts on a variety of molecular assays. The formalin-free, non-cross-linking PAXgene tissue system preserves morphology in a similar way to formalin, but also preserves biomolecules essentially in a similar way to cryopreservation, which markedly widens the spectrum, sensitivity and accuracy of molecular analytics. In this study, we have developed and tested a protocol for PAXgene-fixed and paraffin-embedded tissues for fluorescent in situ hybridization (FISH). The implementation of a 24-h formalin postfixation step of slides from PAXgene-fixed and paraffin-embedded tissues allowed us to use the assays approved for formalin-fixed and paraffin-embedded tissues. The equivalence of the methodologies was demonstrated by FISH analysis of HER2 amplification in breast cancer cases. The 24-h postfixation step of the slides used for FISH can be well integrated in the routine diagnostic workflow and allows the remaining PAXgene-fixed and paraffin-embedded tissue to be used for further molecular testing.

Martina Loibner

Christian Doppler Laboratory for Biospecimen Research and Biobanking Technologies,
Institute of Pathology

Medical University Graz

Protocol for HER2 FISH Using a Non-cross-linking, Formalin-free Tissue Fixative to Combine Advantages of Cryo-preservation and Formalin Fixation

Martina Loibner

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Christian Doppler Laboratory for Biospecimen Research and Biobanking Technologies,Institute of Pathology

Medical University Graz

Protocol for HER2 FISH Using a Non-cross-linking, Formalin-free Tissue Fixative to Combine Advantages of Cryo-preservation and Formalin Fixation

Christian Doppler Laboratory for Biospecimen Research and Biobanking Technologies,
Institute of Pathology