The cell growth inhibitory transcription factor C/EBPdelta is expressed in human meningiomas in association with low histological grade and proliferation index.

CCAAT/enhancer binding protein (C/EBP) delta is a transcription factor which has been demonstrated to mediate the growth arrest of mammary and prostate cancer cell lines. It is induced by several stimuli including inflammatory cytokines. In this study, C/EBPdelta immunohistochemical expression was assessed in 49 meningiomas of different histotype and grade and correlated with a variety of clinico-pathological data and with the overall and recurrence-free survival of the patients. Positive staining was observed in the nuclei of neoplastic cells in 22 out of the 49 cases analyzed. C/EBPdelta expression was significantly associated with a low histological grade and proliferation index, reflected by low Ki-67 labeling index (LI) and mitotic activity, and with the presence of intra-tumoral inflammatory infiltrate and the absence of necrosis. In addition, the absence of C/EBPdelta was significantly correlated with a shorter disease-free interval. Our findings suggest that C/EBPdelta expression may prevent the development of recurrences by inhibition of neoplastic growth in meningiomas. If further studies confirm its induction by inflammatory mediators, this might be exploited in novel therapies to prevent recurrences in meningiomas.