Prognostic impact of adenylyl cyclase-associated protein 2 (CAP2) in glioma: A clinicopathological study

Background: Gliomas are a group of diseases arising from intracranial neoplastic tissues that produce a wide spectrum of clinicopathological features and morphological changes. Key questions that intrigue neuro-oncology researchers include defining novel oncophenotypic signatures relevant to diagnosing such tumors and predicting prognoses among patients. One of the key regulators of the cellular actin dynamics is adenylyl cyclase-associated protein 2 (CAP2), a protein that has been studied before in the milieu of cancer and shown to be associated with tumor progression; yet, its expression levels in the context of gliomas have not been assessed. Hence, we were interested in investigating CAP2 expression in gliomas and evaluating its clinicopathological and prognostic significance. Materials and methods: CAP2 expression at the protein level was analyzed in 47 human paraffin-embedded gliomas and normal brain tissues by automated immunohistochemical analysis. Statistical analysis was also performed to assess CAP2 expression level in normal and tumor tissues, and to evaluate its clinicopathological and prognostic significance. Results: Our results revealed high expression of CAP2 protein in tumors of gliomas compared to normal tissues and normal areas adjacent to tumors. High expression of CAP2 was also associated with advanced tumor grades among gliomas. Kaplan-Meier analysis revealed that high CAP2 expression was associated with poor prognosis of patients with glioma (P < 0.05). In Cox regression analysis, CAP2 expression was indicated as an independent prognostic factor for overall survival (hazard ratio (HR) = 1.843, 95% confidence interval (CI), 1.252-2.714; P < 0.005). Conclusion: CAP2 is overexpressed in glioma and it is proposed as a potential prognostic biomarker for patients with gliomas. CAP2 expression level may serve as a promising target for diagnosis and treatment of glioma.