Determination of the levels of expression of sarcolectin and calcyclin and of the percentages of apoptotic but not proliferating cells to enable distinction between recurrent and nonrecurrent cholesteatomas.
OBJECTIVE
To investigate in a series of cholesteatomas 1. whether subgroups of cholesteatomas with specific proliferative/apoptotic features exhibit distinct differentiation markers and 2. whether these different subgroups identified at the biological level relate to specific groups of clinically identified cholesteatomas.


METHODS
Analysis of 55 cholesteatomas resected by the same surgeon, by means of canal wall up and canal wall down surgical procedures.


METHODS
Two differentiation markers were used: biotinylated sarcolectin (to identify sarcolectin-binding sites) and a monoclonal antibody directed against calcyclin (which is the S100A6 protein). The growth pattern in cholesteatomas was characterized at three distinct levels: 1. the cell proliferation level determined by means of the MIB-1 antibody, which enables the Ki-67 cell-cycle-related antigen to be identified on archival material; 2. the apoptosis level determined by means of the in situ labeling of nuclear DNA fragmentation (TUNEL staining); and 3. the p53 tumor suppressor gene-related product determined by means of p53 immunohistochemistry.


RESULTS
The cholesteatomas that exhibited the highest proportion of apoptotic cells were those which exhibited the highest level of sarcolectin-binding sites (i.e., sialic acids). In contrast, the cholesteatomas exhibiting the lowest level of both proliferation and apoptosis showed the highest level of calcyclin. Recurrent cholesteatomas can be identified from nonrecurrent ones on the basis of three features, namely, the level of apoptotic cells, the way in which the apoptotic cells are distributed (i.e., homogeneously vs. heterogeneously), and the percentage of calcyclin-positive cells.


CONCLUSIONS
The present data emphasize the existence of distinct subgroups of cholesteatomas identifiable at both cell kinetic and differentiation levels. Some of the biological variables used here to identify distinct biological subgroups of cholesteatomas in turn enabled some biological variables to be identified, so making it possible to classify the cholesteatomas in terms of recurrence versus nonrecurrence.
Choufani
G
G
Department of Otolaryngology & Head and Neck Surgery, Erasmus University Hospital, Brussels, Belgium.
Mahillon
V
V
Decaestecker
C
C
Lequeux
T
T
Danguy
A
A
Salmon
I
I
Gabius
H J
HJ
Hassid
S
S
Kiss
R
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D017209:Apoptosis; D018797:Cell Cycle Proteins; D002455:Cell Division; D002648:Child; D018424:Cholesteatoma, Middle Ear / Q000378:metabolism*; D004815:Epidermal Growth Factor / Q000378:metabolism*; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D020287:In Situ Nick-End Labeling; D037102:Lectins / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000378:metabolism*; D009364:Neoplasm Recurrence, Local / Q000378:metabolism*; D012189:Retrospective Studies; D000075383:S100 Calcium Binding Protein A6; D009418:S100 Proteins / Q000378:metabolism*
D018797:Cell Cycle Proteins; D037102:Lectins; D009363:Neoplasm Proteins; D000075383:S100 Calcium Binding Protein A6; D009418:S100 Proteins; C055351:S100A6 protein, human; D004815:Epidermal Growth Factor; C039495:sarcolectin