Circulating MACC1 as a novel diagnostic and prognostic biomarker for nonsmall cell lung cancer.

PURPOSE: Metastasis-associated in colon cancer-1 (MACC1) is a newly identified gene that plays an important role in cancer progression and metastasis. MACC1 has important functions in the differentiation, invasion, and metastasis of nonsmall cell lung cancer (NSCLC). However, the value of circulating MACC1 as a potential diagnostic and prognostic biomarker for NSCLC remains unknown.METHODS: Plasma MACC1 mRNA levels were examined in 272 patients with NSCLC, 61 with benign lung disease, and 80 healthy volunteers using reverse transcription quantitative real-time polymerase chain reaction.RESULTS: MACC1 was more highly expressed in NSCLC patients than in patients with benign disease (P<0.001) or in healthy volunteers (P<0.001). High MACC1 expression was significantly associated with NSCLC stage (P=0.013) and lymph node metastasis (P=0.016). The area under the receiver operating characteristic curve was 0.766, and the optimal cutoff value was 0.105, providing a sensitivity of 71.4% and a specificity of 89.1%. The diagnostic capability of circulating MACC1 mRNA was higher than that of carcinoembryonic antigen (P=0.025) or cytokeratin-19 (P=0.010). Furthermore, high MACC1 expression was associated with poor overall survival (OS) and disease-free survival (DFS) and predicted poor survival in NSCLC patients. Consequently, MACC1 mRNA was an independent prognostic factor of OS and DFS.CONCLUSION: We concluded that circulating MACC1 mRNA represents a potential noninvasive, diagnostic and prognostic marker for NSCLC.