M30 expression demonstrates apoptotic cells, correlates with in situ end-labeling, and is associated with Ki-67 expression in large intestinal neoplasms.
BACKGROUND
The monoclonal antibody M30 recognizes a neoepitope of cytokeratin 18 produced during apoptosis. It is reactive in formalin-fixed, paraffin-embedded tissue and has great potential in the study of apoptosis in clinical and experimental material.


OBJECTIVE
To compare the results of M30 immunoexpression with a more established technique of demonstrating apoptosis in tissue sections, in situ end-labeling. A secondary objective was to compare the results with immunoexpression of the proliferation-associated antigen Ki-67.


METHODS
Retrospective analysis of adenomas and adenocarcinomas of the large intestine.


METHODS
Immunohistochemistry for M30 and Ki-67, and in situ end-labeling. Formalin-fixed, paraffin-embedded tissue was used.


METHODS
The number of cells positive for M30, Ki-67, and in situ end-labeling, expressed as a proportion of the total number of cells counted.


RESULTS
A strong positive correlation was found between in situ end-labeling and expression of M30, although the counts were widely scattered around the regression line. Counts of Ki-67 were strongly correlated with both M30 expression and in situ end-labeling. Immunoexpression of M30 was generally easier to interpret than in situ end-labeling, and the procedures for M30 immunohistochemistry were technically less exacting.


CONCLUSIONS
These findings support the application of M30 immunoreactivity in the study of apoptosis.
Carr
N J
NJ
Department of Pathology, Royal Hospital Haslar, Gosport, Hampshire, United Kingdom.
D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000911:Antibodies, Monoclonal; D017209:Apoptosis; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007414:Intestinal Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D007420:Intestine, Large / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D007633:Keratins / Q000096:biosynthesis* / Q000276:immunology; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D013223:Statistics as Topic
D000911:Antibodies, Monoclonal; D019394:Ki-67 Antigen; D007633:Keratins