Expression and prognostic value of MCM2 in type B thymomas.

BACKGROUND: Thymic epithelial tumors (TETs) are the most common mediastinal malignancies, lacking reliable prognostic biomarkers. This study aimed to identify a potential prognostic marker for TETs. METHODS: mRNA microarray analysis of 30 tumor and peritumoral tissues identified differentially expressed genes (DEGs). Hub genes were selected via protein-protein interaction (PPI) analysis, with MCM2 chosen as the target gene. Survival and enrichment analyses were performed, and a validation cohort assessed MCM2's association with prognosis and clinicopathological features. RESULTS: Seven hundred thirty-four DEGs were identified, with MCM2 significantly associated with prolonged progression-free survival (PFS) (HR = 0.17; 95% CI: 0.05-0.54; p = 0.003) and identified as an independent risk factor for PFS (HR = 0.26; 95% CI: 0.08-0.91; p = 0.035). MCM2 expression decreased from type B1 to B3 thymomas. CONCLUSIONS: MCM2 is an independent prognostic factor for TETs, with higher expression linked to better PFS and decreasing expression across B-type thymomas, suggesting its role as a favorable prognostic marker.