Increased expression of Trop2 correlates with poor survival in extranodal NK/T cell lymphoma, nasal type

Human trophoblastic cell surface antigen 2 (Trop2) has been suggested to play an important role in the development of solid tumors. However, the expression of Trop2 in extranodal NK/T cell lymphoma, nasal type (ENKTL) and the relationship with the clinical characteristics of this disease remain poorly understood. In this study, one-step quantitative PCR reverse transcription-polymerase chain reaction and immunohistochemical staining with tissue sections were employed to evaluate the expression of Trop2 in ENKTL. Furthermore, the relationship between Trop2 expression and prognosis of ENKTL was investigated. Expression of Trop2 mRNA and protein was significantly higher in ENKTL tissue than in corresponding non-lymphomatous tissue (p = 0.04 and p < 0.001, respectively). Expression of Trop2 protein in ENKTL was associated with lymph node involvement and poor overall survival (p = 0.045 and p = 0.018, respectively). Kaplan-Meier analysis and the logrank test indicated that lymph node involvement (p = 0.0481), single therapy strategy (p = 0.0037), and high expression of Trop2 (p = 0.0042) are significantly correlated with poor prognosis of ENKTL patients. The data suggest that Trop2 expression reflects a more malignant phenotype and may serve as an unfavorable prognostic factor for ENKTL.