Dual-specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) as a novel marker in T1 high-grade and T2 bladder cancer patients receiving neoadjuvant chemotherapy

Background: To investigate associations between dual-specificity tyrosine phosphorylation-regulated kinase 2 (DYRK2) expression and survival in T1 high-grade or T2 bladder cancer patients treated with neoadjuvant chemotherapy. Methods: The cohort under investigation comprised 44 patients who underwent neoadjuvant chemotherapy for pT1 high-grade or pT2N0M0 bladder cancer at our institution between 2002 and 2011. Immunohistochemical analysis was used to determine expression of DYRK2 in bladder cancer specimens obtained by transurethral resection before chemotherapy. Relationships between DYRK2 expression and both response to chemotherapy and survival in these patients were analyzed. Results: DYRK2 expression was positive in 21 of 44 patients (47.7 %) and negative in 23 patients (52.3 %). In total, 20 of 21 DYRK2-positive cases showed complete response to neoadjuvant chemotherapy, whereas 11 of 23 DYRK2-negative cases did not show complete response. Sensitivity and specificity were 62.5 % and 91.7 %, respectively (P = 0.0018). In addition, disease-specific survival rate was significantly higher for DYRK2-positive patients than for DYRK2-negative patients (P = 0.017). In multivariate analysis, DYRK2 expression level was identified as an independent prognostic factor for disease-specific survival (P = 0.029). We also showed that DYRK2 mRNA expression was significantly higher in DYRK2-positive samples by immunohistochemistry than DYRK2-negative samples (P = 0.040). Conclusions: DYRK2 expression level may predict the efficacy of neoadjuvant chemotherapy for T1 high-grade and T2 bladder cancer.