EXPRESSION EVALUATED BY DIGITAL IMAGE ANALYSIS TECHNIQUES OF PRAME MORE THAN MCM6 IS ASSOCIATED WITH POOR PROGNOSIS IN NEUROBLASTOMA: A PILOT STUDY WITH 84 CASES.

Neuroblastoma is a common childhood tumor originating from neural crest progenitors with variable clinical behavior. Despite improved overall survival, factors such as stage, histoprognosis, MYCN status, and age still influence outcome. MCM6 regulates DNA replication and contributes to cancer progression. PRAME, first identified in melanoma, also acts on cell replication, epithelial-mesenchymal transition, and cell migration and has been associated with poor outcomes in several cancers, including neuroblastoma, using molecular biology techniques. The study aims to investigate MCM6 and PRAME expression and prognostic roles in neuroblastoma. A retrospective study was conducted, which included data of 84 patients with neuroblastoma diagnosed between 2000 and 2022, sourced from the pediatric tumor registry. Patient's characteristics and prognostic tumor factors were collected. Expression of MCM6 and PRAME proteins was evaluated using digital image analysis techniques. Univariate and multivariate analyses were performed using Cox regression to assess the impact of protein expression on survival and their associations with these prognostic factors. A total of 84 children diagnosed with neuroblastoma were included. MCM6 and PRAME were associated with unfavorable histologies (p=0.03). PRAME was associated with bone marrow metastases (p<0.01), high mitotic-karyorrhectic index (p=0.04), and poor histoprognosis (p<0.01). PRAME and MCM6 expression was correlated with several neuroblastoma prognostic factors. PRAME was significantly (p=0.05) associated with poor event-free survival (EFS) and not significantly (p=0.08) associated with overall survival (OS). Although statistical significance was not reached in multivariate analysis, the trends strongly suggested that the overexpression of MCM6 and PRAME was correlated with decreased survival.