Immunohistochemical Expression of D2 Dopamine Receptor and p53 Protein in 170 Meningiomas

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 326-337-Hormone-Dependent Tumors
Bench to Bedside
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-336
Miriam da Costa Oliveira*1, Julia Fernanda Semmelmann Pereira-Lima1, Geraldine Trott2, Carolina G.S. Leaes3, Marícia Fantinel D'Ávila4 and Nelson Pires Ferreira4
1Center of Neuroendocrinology / Santa Casa of Porto Alegre - UFCSPA, Porto Alegre, Brazil, 2Postgraduate Program in Pathology, Universidade Federal de Ciências da Saúde de Porto Alegre (UFCSPA), Porto Alegre, Brazil, 3Center of Neuroendocrinology / Santa Casa of Porto Alegre - UFCSPA, Porto Alegre, Brazil, 4Center of Neuroendocrinology / Santa Casa of Porto Alegre - UFCSPA, Porto Alegre, Brazil
Introduction: Meningiomas constitute approximately 20% of all intracranial tumors. They are classified in grades I and II with benign behavior and grade III, malign. Although these tumors are predominantly benign (grades I or II), they have a high recurrence rate. Some studies suggest the role of the D2 dopamine agonists in reducing cell proliferation in meningiomas the presence of D2 receptors in these neoplasms. However, studies are still scarce in the literature. The determination of p53 expression may suggest the proliferative activity of meningiomas and can serve as a predictor of future recurrence. Objective: The aim of this study was to evaluate the expression of dopamine D2 receptor (DR-D2) and p53 protein by immunohistochemistry (IH) in meningiomas. Material and Methods: Tumor tissue samples of 170 patients diagnosed with meningiomas were fixed in formalin and embedded in paraffin. The material removed was subjected to the IH technique to determine p53 protein and DR-D2 expression. Tumors were classified into grades I-III according to World Health Organization. Medical records were accessed to collect clinical data. Results: Of 170 patients, 77.7% were females and the average age was 53.18±14.59 years. Immunohistochemical expression of DR-D2 was detected in 77% of patients, with no statistically significant difference between tumor grade, sex and age. Regarding the p53 protein immunohistochemical expression it was observed in 41.7% of the samples, with a mean age significantly higher of patients with positive IH (p=0,04). Grade II and III meningiomas presented IH positive for p53 significantly higher than grade I (p=0.01). There was no statistical difference in relation to sex between the patients with IH positive for p53. Conclusions: There is IH expression of p53 protein in approximately half of meningiomas and high degree of IH expression of DR-D2. The IH expression of p53 was greater with the increase of age, as well as the anatomopathological graduation, grade II-III showing the highest percentage of positivity. Based on these findings, further studies are needed to expand knowledge in the monitoring of these tumors, as well as possible future implications in its therapeutic.

Nothing to Disclose: MDCO, JFSP, GT, CGSL, MFD, NPF

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm