Expression of DNA repair proteins in endometrial cancer predicts disease outcome

Objective The consequences of defective homologous recombination and other DNA repair pathways are important in disease outcomes of numerous tumor types. The objective of this study was to explore BRCA1, PARP, FANCD2, PTEN, H2AX, and ATM protein expression in endometrial cancer (EC). Methods PARP1, γH2AX, ATM, FANCD2, PTEN, BRCA1, and p53 proteins were evaluated in EC tissue microarray (TMA) and their expressions were correlated with clinical and pathological parameters in 357 patients. Results In type I EC, PARP1 ⁺, ATM⁺, and FANCD2⁺ were associated with high tumor grade (p 0.031, p 0.0045, p 0.0062 respectively); γH2AX⁺ and FANCD2⁺ with advanced tumor stage (p 0.0004, p 0.0085 respectively); γH2AX⁺, FANCD2⁺ and p53⁺ with the presence of lympho-vascular invasion (p 0.0004, p 0.0042, p 0.0098 respectively); and γH2AX⁺ and ATM⁺ with tumor recurrence (p 0.0203, p 0.0465) respectively. In type II EC, only PARP1 ⁺ was associated with tumor stage (p 0.0499). EC patients with p53⁺ or FANCD2⁺ were more likely to recur with 5 year recurrence free survival (RFS) probability of 71.4% in comparison to 85.5% for the other patients and they were more likely to have shorter 5 year overall survival (OS) of 66.46% in comparison to 78.5% of those other patients Finally, patients with ATM⁺ and p53⁺ or FANCD2⁺ were more likely to recur with 5 year RFS probability of 68% versus 80.3% for the other patients. Conclusion DNA repair proteins seemed to play an important role in EC, and their expressions can forecast for poor outcomes.