Prognostic values of neutrophil gelatinase-associated lipocalin and matrix metalloproteinase-9 in lung adenocarcinoma

Objective To investigate the relationship between the expression of neutrophil gelatinase-associated lipocalin (NGAL) and matrix metalloproteinase-9 (MMP-9) in lung adenocarcinoma with prognosis and overall survival (OS). Methods A retrospective analysis was made on 50 patients with lung adenocarcinoma treated from Jan. 2012 to Jan. 2016 in our hospital. Tumor tissue was analyzed for NGAL and MMP-9 expression by immunohistochemistry. Results Mean overexpression in tumoral tissue was 70% for NGAL and 30% for MMP-9. Univariate analysis revealed that prognostic factors associated with OS were NGAL expression and stage at diagnosis. Median OS for NGAL expression <70% was 45.7 months (95%CI: 15.2-76.2) and that for NGAL expression ≥70% was 4.6 months (95%CI: 0.5-18.8; P=0.000). The median OS for stage Ⅲ was 15.6 months (95%CI: 9.8-21.2) and that for stage Ⅳ was 9.6 months (95%CI: 0.8-18.4, P=0.002). The expression of MMP-9 in tumor tissues was not correlated with OS. Conclusion The expression of NGAL ≥70% in tumor tissues confers a worse prognosis. NGAL is an independent prognostic factor of stage at diagnosis. Key words: Lipocalin; Adenocarcinoma; Matrix metalloproteinase