title: Modified formalin and methanol fixation methods for molecular biological and morphological analyses.
abstract: Several simplified fixation methods were examined to determine their suitability for both molecular biological analyses and morphological study. Fixation with 10% v/v formalin alone at 4 degrees C and containing 5 mmol/L ethylenediamine-N,N,N',N'-tetraacetic acid (EDTA) at room temperature preserved significantly more high-molecular-weight DNA than 10% v/v formalin fixation at room temperature. The morphological differences between tissues fixed using these modified formalin fixation methods and conventional 10% v/v formalin fixation were negligible. Of the dehydration fixatives tested, 100% methanol did not cause regional differences due to artificial tissue shrinkage and the morphology of sections prepared by methanol fixation was preserved consistently better than that of acetone- or ethanol-fixed sections. All three dehydration fixatives preserved relatively higher-molecular-weight DNA and RNA, compared with formalin. Cold formalin, formalin containing EDTA at room temperature and 100% methanol are recommended as standard and additional fixatives routine clinicopathological laboratory use.
authors.affiliation: Pathology Division, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Noguchi
authors.forename: S
authors.initials: S
authors.lastname: Furuya
authors.forename: T
authors.initials: T
authors.lastname: Takeuchi
authors.forename: S
authors.initials: S
authors.lastname: Hirohashi
mesh_terms: D001940:Breast / Q000737:chemistry; D001943:Breast Neoplasms / Q000235:genetics; D003106:Colon / Q000737:chemistry; D003110:Colonic Neoplasms / Q000235:genetics; D004247:DNA / Q000032:analysis*; D005404:Fixatives / Q000494:pharmacology; D005557:Formaldehyde / Q000494:pharmacology*; D005753:Gastric Mucosa / Q000033:anatomy & histology; D006801:Humans; D008099:Liver / Q000737:chemistry; D008168:Lung / Q000737:chemistry; D008175:Lung Neoplasms / Q000235:genetics; D000432:Methanol / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D012313:RNA / Q000032:analysis*; D013270:Stomach / Q000033:anatomy & histology / Q000737:chemistry; D013274:Stomach Neoplasms / Q000235:genetics; D016707:Tissue Fixation / Q000379:methods*
chemical_list: D005404:Fixatives; D005557:Formaldehyde; D012313:RNA; D004247:DNA; D000432:Methanol