The clinical significance of Cyclin B1 and Wee1 expression in non-small-cell lung cancer

Background: Cyclin B I has an important role in the G(2)-M phase transition of the cell cycle. Wee I delays mitosis by suppressing the activity of the Cyclin B1/cdc2 complex. The objective of the present study was to elucidate the clinicopathological and prognostic significance of Cyclin B I and Wee I expression in non-small-cell lung cancer (NSCLC). Patients and methods: An immunohistochemical assessment of Cyclin B1 and Weel expression was performed in 79 patients with NSCLC. Results: The expression of Cyclin B1 was correlated with differentiation (P = 0.0423) and vascular invasion (P = 0.001). Patients with overexpression of Cyclin B I had higher mean values for both the Ki-67 proliferative index (Ki-Index) (P <0.0001) and proliferating cell nuclear antigen labeling index (PCNA-LI) (P <0.0001), and a poorer prognosis (P = 0.0068). Patients lacking expression of Weel had a higher recurrence rate (P = 0.0084) and a poorer prognosis (P = 0.0457), and tended to have higher Ki-Index and PCNA-LI values. Multivariate analysis suggested that both Cyclin B1 (P = 0.0244) and Weel (P = 0.0444) expression were significant prognostic factors. Conclusions: These findings suggest that Cyclin B I expression could be a significant prognostic parameter in NSCLC. The loss of Wee I expression may have a potential role in promoting tumor progression and may be a significant prognostic indicator in NSCLC.