title: A Buffered Alcohol-Based Fixative for Histomorphologic and Molecular Applications.
abstract: Formalin-fixed paraffin-embedded (FFPE) tissue is the predominant preparation for diagnostic histopathological evaluation and increasingly the biospecimen on which molecular diagnostics are performed. However, formalin is carcinogenic and results in cross-linking of proteins and nicking and alterations of nucleic acids. Alternative fixatives, including 70% ethanol, improved biomolecular integrity; however, they have yet to replace neutral-buffered formalin (NBF). Herein, we describe the phosphate-buffered ethanol 70% (BE70) fixative. The histomorphology of BE70-fixed tissue is very similar to that of NBF; however, it is a non-cross-linking fixative and lacks the carcinogenic profile of formaldehyde-based fixatives. RNA isolated from tissue fixed in BE70 was of substantially higher quality and quantity than that was recovered from formalin-fixed tissue. Furthermore, the BE70 fixative showed excellent RNA and DNA integrity compared with that of NBF fixative based on real-time polymerase chain reaction analysis results. Immunohistochemical staining was similar for the antigen tested. In conclusion, BE70 is a non-cross-linking fixative that is superior to NBF and 70% ethanol with reference to biomolecule recovery and quality from paraffin-embedded tissue. Additional studies to compare the histomorphologic and immunohistochemical performance and utility in a clinical setting are required.
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)|Antibody Characterization Laboratory, Advanced Technology Program, Leidos Biomedical Research, Inc., Frederick, Maryland (CP)
authors.forename: Candice
authors.initials: C
authors.lastname: Perry
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: Joon-Yong
authors.initials: JY
authors.lastname: Chung
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: Kris
authors.initials: K
authors.lastname: Ylaya
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)|Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea (CHC)
authors.forename: Chel Hun
authors.initials: CH
authors.lastname: Choi
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: Amari
authors.initials: A
authors.lastname: Simpson
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: Kaipo T
authors.initials: KT
authors.lastname: Matsumoto
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: William A
authors.initials: WA
authors.lastname: Smith
authors.affiliation: Experimental Pathology Laboratory, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland (CP, J-YC, KY, CHC, AS, KTM, WAS, SMH)
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Hewitt
mesh_terms: D000818:Animals; D002021:Buffers; D004247:DNA / Q000032:analysis; D000431:Ethanol; D005404:Fixatives; D006652:Histological Techniques; D007668:Kidney / Q000737:chemistry / Q000166:cytology; D051379:Mice; D010710:Phosphates; D011506:Proteins / Q000032:analysis; D012313:RNA / Q000032:analysis; D016707:Tissue Fixation / Q000379:methods
chemical_list: D002021:Buffers; D005404:Fixatives; D010710:Phosphates; D011506:Proteins; D000431:Ethanol; D012313:RNA; D004247:DNA
keywords: RNA integrity; alcohol; fixation; formalin; histomorphology; paraffin embedded; real-time RT-PCR; tissue