Lack of Alkaline Phosphatase Activity Predicts Meningioma Recurrence

Abstract

Meningiomas usually are benign intracranial tumors. However, some recur despite gross total resection, invade surrounding structures, or, rarely, metastasize. Reduced expression of the nonspecific tissue-type alkaline phosphatase (Pal) has been reported in high-grade meningiomas. To search for a predictor for recurrence, we studied Pal expression by histoenzymology in a series of 54 meningiomas with gross total removal. Pal expression was mostly altered in grades II and III meningiomas (P = .000014) and meningiomas with high MIB-1 values (P = .001). Pal expression correlated with cytogenetic data (P = .000033) and with recurrence (P = .0064); all tumors that recurred had abnormal Pal expression (13/13). In univariate analysis, Pal expression was the only variable correlated with recurrence-free survival (P = .035). Histochemical detection of Pal is a useful, easy, and low-cost technique to predict recurrence in meningiomas.

Microarray gene expression profiling in meningiomas: Differential expression according to grade or histopathological subtype

“…This is in agreement with histoenzymological reports showing reduced levels of HOPS enzyme in high-grade meningiomas (42,43). Moreover, reduced HOPS protein expression had been reported in a grade I meningioma in one patient who presented recurrence after surgery (42). In our study, the 3 grade I meningiomas which were included by molecular clustering in the group of atypical meningiomas also showed reduced HOPS transcript expression.…”

“…Interestingly, our results demonstrated a dramatic downregulation of alkaline phosphatase (HOPS) mRNA expression in atypical and anaplastic meningiomas, by microarray and, in a larger number of patients by RT-PCR. This is in agreement with histoenzymological reports showing reduced levels of HOPS enzyme in high-grade meningiomas (42,43). Moreover, reduced HOPS protein expression had been reported in a grade I meningioma in one patient who presented recurrence after surgery (42).…”

Hyperdiploidy defines a distinct cytogenetic entity of meningiomas

“…Thus, a focal or complete loss of alkaline phosphatase activity indicates tumor progression. Recently, Bouvier et al [33] demonstrated that alteration of alkaline phosphatase is strongly associated with recurrence in meningiomas. Within this series of hyperdiploid meningiomas, in each tumor at least focal loss of enzyme activity, in three cases even complete loss was found.…”

Magnetic resonance and computed tomographic imaging characteristics and potential molecular mechanisms of feline meningioma associated calvarial hyperostosis

“…Human meningiomas also have a cleaved chromosome 1p36.1‐p34 that suppresses or blocks ALP activity 29 . Reduced non‐specific tissue ALP expression has been described in high grade meningiomas compared to lower grade tumours, with reduced ALP expression correlated to increased risk of tumour recurrence 29,31 . No significant differences were identified related to serum ALP or bALP concentrations in cats with or without CH in this study, and intratumoral bALP in cats was not detectable using ELISA.…”