Objectives: We investigated the possibility of DYRK2, a dual-specificity tyrosine-(Y)-phosphorylation-regulated kinase gene, to predict survival for patients with pulmonary adenocarcinoma.
Patients and methods: One hundred forty-four patients with pulmonary adenocarcinoma underwent surgery in our institute from 2000 to 2008. We used immunohistochemical analysis and real-time reverse-transcriptase polymerase chain reaction to determine the expression of DYRK2 and compared this with the clinicopathologic factors and survival.
Results: We found no correlation between DYRK2 expression by immunohistochemical and clinicopathologic factors; however, a negative nodal status and negative lymphatic invasion were significantly associated with DYRK2 expression by reverse-transcriptase polymerase chain reaction. Five-year disease-free survival in the DYRK2-positive group (75.4%) was significantly different from that in the negative group (55.4%; P = .03) by immunohistochemical analysis. The 5-year overall survival of 89.2% in the DYRK2-positive group was better than the 66.3% survival of the DYRK2-negative group (P = .01). Quantitative real-time reverse-transcriptase polymerase chain reaction analyses showed a significant difference between positive and negative expressions for disease-free survival (P = .003) and overall survival (P = .007). In multivariate Cox regression analysis, negative DYRK2 protein and messenger RNA expression showed a worse prognostic value of survival (hazard ratio [HR] = 4.7, 95% confidence intervals [CI] = 1.5-14.5, P=.007; HR = 2.5, 95% CI = 1.1-6.1, P = .04, respectively). When we analyzed adenocarcinoma cases except for bronchioloalveolar carcinoma, we found a close correlation between DYRK2 expression by immunohistochemical analysis and nodal status (P = .03). Furthermore, disease-free survivals between positive and negative groups of DYRK2 expression by immunohistochemistry (P = .03) and reverse-transcriptase polymerase chain reaction (P = .02) without bronchioloalveolar carcinoma were significantly different. Overall survivals in both groups showed significant differences by immunohistochemistry (P = .02) but not by reverse-transcriptase polymerase chain reaction (P = .08).
Conclusions: These data showed that DYRK2 expression is associated with a favorable prognosis.