Backgound and Objectives : Cancer is a disease characterized by deregulation of cell cycle control.
During the last decade, many alterations in the signaling pathways that ultimately lead to DNA
replication and mitosis have been identified in various tumor types. DNA analysis by flow
cytometry is considered to be of prognostic value in squamous cell carcinoma of the head the cell
cycle control gene cyclin D1 may, at least in some tumor types, provide a prognostic marker.
Cyclin D1 is expressed during the G1 phase of the cell cycle and becomes associated with its
catalytic partner CDK4 or CDK6. The authors evaluated the prognostic significance of cyclin D1,
DNA ploidy and S-phase fraction (SPF) in the squamous cell carcinoma of the larynx to
determine their relationship with the various clinicopathological parameters.
Materials and Methods : Paraffin embedded tissue specimens from 28 cases of squamous cell
carcinoma of larynx were studied by the immunohistochemical method using cyclin D1 antibody
and by flow cytometric DNA analysis.
Result : The positive expression of cyclin D1 protein was 60.7％ in squamous cell carcinoma of
the larynx. In 28 cases of flow cytometric DNA analysis, 23 cases(82.1％) were diploidy and 5
cases(17.9％) were aneuploidy. The SPE ranged from 0.0％ to 83.9％ (mean 41.4, median 35.2).
The mean SPF of DNA diploid cases was 34.2％, whereas that of DNA aneuploid was 74.7％.
Expression of cyclin D1 protein was found in 52.2％ of the diploid cases and in 100％ of the
aneuploid cases. This expression was statistically significant(p＜0.05). Among the multiple factors,
only the lymph node metastasis was found to be statistically significant in aneuploid cases and in
higher SPF(≥35.2). The expression of cyclin D1 protein did not correlate with clinical features.
Conclusion : the expression of cyclin D1 protein may be related with development of squamous
cell carcinoma of the larynx, but nor correlated with prognostic indicators. In cases of
aneuploidy/higher SPF(≥35.2), The expression of cyclin D protein did not significantly correlate
with lymph node metastasis, but showed a high expression rate of cyclin D1 protein. However,
these correlations were not sufficient for the prognostic indicators in squamous cell carcinoma of
the larynx.
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