Serum integrin-linked kinase (sILK) concentration and survival in non-small cell lung cancer: A pilot study

Background: Integrin-linked kinase (ILK) is an intracellular signaling protein critically involved in cellular growth and motility. In non-small cell lung cancer (NSCLC), increased ILK expression has been associated with decreased recurrence-free and overall survival. Recently, ILK has also been detected in the serum of NSCLC patients. Objective: To assess the prognostic impact of preoperative serum ILK (sILK) concentration on overall survival in surgically amenable NSCLC. Patients and methods: Preoperative sILK was quantified by ELISA in 50 newly diagnosed NSCLC patients. After surgery, patients were followed-up for a median interval of 2.5 years. Results: Serum ILK concentrations ranged from 0 to 2.44 ng/ml. Mean sILK was around 2.3 times higher in the 16 patients who died as compared to the 34 patients who survived (1.04 vs. 0.45 ng/ml, p = 0.001). In univariate time-to-event analysis, increased sILK was associated with adverse survival [Hazard ratio (HR): 4.03, 95 % CI: 2.00-8.13, p < 0.001]. This association prevailed after multivariable adjustment for several clinical, demographic, and laboratory parameters (HR: 3.85, 95 % CI: 1.53-9.72, p = 0.004). Conclusions: Serum ILK shows potential as a novel strong and independent prognostic marker for postoperative survival in surgically amenable NSCLC.