Expression and prognostic role of IKBKE and TBK1 in stage I non-small cell lung cancer.

BACKGROUND: The inhibitors of nuclear factor kappa-B kinase subunit epsilon (IKBKE) and TANK-binding kinase 1 (TBK1) are important members of the nonclassical IKK family that share the kinase domain. They are important oncogenes for activation of several signaling pathways in several tumors. This study aims to explore the expression of IKBKE and TBK1 and their prognostic role in stage I non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: A total of 142 surgically resected stage I NSCLC patients were enrolled and immunohistochemistry of IKBKE and TBK1 was performed. RESULTS: IKBKE and TBK1 were expressed in 121 (85.2%) and 114 (80.3%) of stage I NSCLC patients respectively. IKBKE expression was significantly associated with TBK1 expression (P=0.004). Furthermore, multivariate regression analyses showed there was a significant relationship between patients with risk factors, the recurrence pattern of metastasis and IKBKE+/TBK1+ co-expression (P=0.032 and P=0.022, respectively).  In Kaplan-Meier survival curve analyses, the IKBKE+/TBK1+ co-expression subgroup was significantly associated with poor overall survival (P=0.014). CONCLUSIONS: This is the first study to investigate the relationship between IKBKE and TBK1 expression and clinicopathologic characteristics in stage I NSCLC patients. IKBKE+/TBK1+ co-expression was significantly obvious in patients with risk factors and with recurrence pattern of distant metastasis. Furthermore, IKBKE+/TBK1+ is also an effective prognostic predictor for poor overall survival.