title: Prognostic significance of cyclin a expression in meningiomas.
abstract: Unconstrained cell proliferation is characteristic of tumors. It is caused by the functional disorders of proteins that constitute the cell cycle mechanism. The cell cycle is controlled by cyclins, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors. Many reports have proved, in cancers, that cyclins, cyclin-dependent kinases, and cyclin-dependent kinase inhibitors are out of control. Cyclin A is a protein that regulates critical transition of the cell cycle. The expression of cyclin A in meningiomas by immunohistochemical method was investigated. Furthermore, the correlation among cyclin A expression, clinical course, and proliferative potential were also evaluated. Seventy-seven meningiomas were studied. The mean cyclin A labeling indices were as follows: benign meningiomas, 1.01% +/- 0.62%; atypical meningiomas, 4.23% +/- 1.82%; and anaplastic meningiomas, 7.72% +/- 0.88%. Analyses of variance showed that significant differences existed between tumor grades for cyclin A labeling indices. A linear positive correlation between the cyclin A labeling index and bromodeoxyuridine labeling index was observed. The multivariate analysis using Cox's hazards model showed a high cyclin A labeling index (>3%) was a significant risk factor for recurrence. A high Ki-67 labeling index (>5%) and high tumor grade (World Health Organization grade II, III) were also significant risk factors for recurrence. These results suggested that the evaluation of cyclin A expression in meningiomas provides significant clinical information, especially as an independent prognostic indicator.
authors.affiliation: Department of Neurosurgery, Kochi Medical School, Kohasu, Okou-cho, Nankoku 783-0505, Japan. nakarinh@kochi-ms.ac.jp
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Nakabayashi
authors.forename: Keiji
authors.initials: K
authors.lastname: Shimizu
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Hara
mesh_terms: D000328:Adult; D000368:Aged; D001973:Bromodeoxyuridine; D019925:Cyclin A; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008577:Meningeal Neoplasms / Q000378:metabolism*; D008579:Meningioma / Q000378:metabolism*; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis
chemical_list: D019925:Cyclin A; D019394:Ki-67 Antigen; D001973:Bromodeoxyuridine