A critical appraisal of the immunohistochemical detection of the c-myc oncogene product in colorectal cancer.
AffiliationDepartment of Immunology, Paterson Institute for Cancer Research, Manchester, UK.
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AbstractExpression of c-myc was studied immunohistochemically in 100 colorectal carcinomas, using a monoclonal antibody, Myc 1-6E10, which is purported to recognize the oncoprotein (p62c-myc) in paraffin-embedded material. In normal epithelium, maturing crypt cells and terminally differentiated surface cells were positive, and proliferating basal crypt cells negative. All carcinomas stained positively, but intensity was independent of histological differentiation, Dukes' stage, DNA ploidy and survival. Staining was predominantly cytoplasmic despite the suspected nuclear location of p62c-myc and there was considerable staining of fibroblasts. When staining was compared in frozen and paraffin-embedded sections fixed in different ways, different patterns were observed. Acetone-fixed frozen sections exhibited weak nuclear and cytoplasmic staining or were negative. In formol-saline fixed frozen sections, there was stronger predominantly nuclear staining. In paraffin-embedded sections staining was predominantly cytoplasmic. This study suggests that c-myc expression is enhanced in the majority of colorectal carcinomas and although independent of clinical behaviour, may be a common event in malignant transformation. However, since staining is affected by fixation and processing, data obtained using Myc 1-6E10 on routinely processed specimens should be interpreted with caution.
CitationA critical appraisal of the immunohistochemical detection of the c-myc oncogene product in colorectal cancer. 1987, 56 (6):779-83 Br. J. Cancer
JournalBritish Journal of Cancer
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- Authors: Stewart J, Evan G, Watson J, Sikora K
- Issue date: 1986 Jan
- Distribution of cells expressing myc proteins in human colorectal epithelium, polyps, and malignant tumors.
- Authors: Melhem MF, Meisler AI, Finley GG, Bryce WH, Jones MO, Tribby II, Pipas JM, Koski RA
- Issue date: 1992 Nov 1
- Phosphotyrosine, p62 c-myc and p21 c-Ha-ras proteins in colonic epithelium of normal and dimethylhydrazine-treated rats: an immunohistochemical analysis.
- Authors: Schwartz B, Benharroch D, Prinsloo I, Cagnano E, Lamprecht SA
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- Detection of the c-myc oncogene product in testicular cancer.
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- c-myc oncogene expression in colorectal cancer.
- Authors: Sikora K, Chan S, Evan G, Gabra H, Markham N, Stewart J, Watson J
- Issue date: 1987 Apr 1
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