The combination of low cytoplasmic and high nuclear expression of p27 predicts a better prognosis in high-grade astrocytoma

Abstract

Background: The function of the cyclin-dependent kinase (cdk) inhibitor p27 is regulated by translocation between the nucleus (activate) and the cytosol (inactivate). No previous reports have examined the subcellular localization of p27 in glioma which was evaluated here regarding the prognosis in high-grade astrocytomas.

Patients and methods: The pattern of subcellular localization of p27 expression was examined immunohistochemically in 49 patients with high-grade astrocytoma who were over 20 years of age. The relationship between p27 localization and the prognosis was statistically examined.

Results: Kaplan-Meier survival analysis showed that cytoplasmic p27 expression was statistically associated with a worse prognosis (p = 0.0203), while nuclear p27 expression showed some tendency towards a better prognosis (p = 0.1180). Cox multiple regression analysis showed the combination of high nuclear and low cytoplasmic p27 expression associated with a significantly better prognosis in high-grade astrocytoma.

Conclusion: A combination of low cytoplasmic and high nuclear expression of p27 predicts a better prognosis in high-grade astrocytomas and thus the subcellular localization of p27 expression is useful for predicting the prognosis for these patients.