Cdc2 expression in primary thyroid lymphoma: its relationship with biological aggressiveness and G2 cyclins.

Previous studies have demonstrated that the G2-M modulators contribute to the progression of human neoplasms. In this study, we investigated the expression of these modulators, cyclin-dependent kinase 1 (cdc2), and G2 cyclins, cyclin A and cyclin B1, in primary thyroid lymphoma. Cdc2 immunoexpression was observed in 51.0% of the 49 cases examined and was related to grade of malignancy, high Ki-67 labeling index, and aberrant p53 expression. The incidences of immunoexpression of cyclin A and cyclin B1 were 63.3% and 40.9%, respectively, and they were also related to the above three parameters. Furthermore, a correlation was found between the immunoexpression of cdc2 and G2 cyclins. These findings suggest that the cdc2 and G2 cyclins play an important role in the progression of thyroid malignant lymphoma.