Enrico Berrino, Laura Annaratone, Paolo Detillo, Dora Grassini, Alberto Bragoni, Anna Sapino, Benedetta Bussolati, Giovanni Bussolati, Caterina Marchiò
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引用次数: 3
Abstract
Introduction: Optimization of pre-analytic procedures and tissue processing is a basic requirement for reliable and reproducible data to be obtained. Tissue fixation in formalin represents the extensively favored method for surgical tissue specimen processing in diagnostic pathology; however, formalin fixation exerts a blasting effect on DNA and RNA.
Methods: A formic acid-deprived formaldehyde solution was prepared by removing acids with an ion-exchange basic resin and the concentrated, acid-deprived formaldehyde (ADF) solution was employed to prepare a 4% ADF solution in 0.1 M phosphate buffer, pH 7.2-7.4. Human (n = 27) and mouse (n = 20) tissues were fixed in parallel and similar conditions in either ADF or neutral buffered formalin (NBF). DNAs and RNAs were extracted, and fragmentation analyses were performed.
Results: Besides no significant differences in terms of extraction yield and absorbance ratio, ADF fixation reduced DNA fragmentation, i.e., the largest fragments (>5,000 bp) were significantly more prevalent in the DNAs purified from ADF-fixed tissues (p < 0.001 in both cohorts). Moreover, we observed that DNA preservation is more stable in ADF-fixed tissue compared to NBF-fixed tissues.
Conclusion: Although DNA fragmentation in FFPE tissues is a multifactor process, we showed that the removal of formic acid is responsible for a significant improvement in DNA preservation.
期刊介绍:
''Pathobiology'' offers a valuable platform for the publication of high-quality original research into the mechanisms underlying human disease. Aiming to serve as a bridge between basic biomedical research and clinical medicine, the journal welcomes articles from scientific areas such as pathology, oncology, anatomy, virology, internal medicine, surgery, cell and molecular biology, and immunology. Published bimonthly, ''Pathobiology'' features original research papers and reviews on translational research. The journal offers the possibility to publish proceedings of meetings dedicated to one particular topic.