NKX2–1 expression as a prognostic marker in early-stage non-small-cell lung cancer

Abstract Background NKX2–1, a key molecule in lung development, is highly expressed in non-small cell lung cancer (NSCLC), particularly in lung adenocarcinoma (ADK), where it is a diagnostic marker. Studies of the prognostic role of NKX2–1 in NSCLC have reported contradictory findings. Two microRNAs (miRNAs) have been associated with NKX2–1: miR-365, which targets NKX2–1; and miR-33a, which is downstream of NKX2–1. We have examined the effect of NKX2–1, miR-365 and miR-33a on survival in a cohort of early-stage NSCLC patients and in sub-groups of patients classified according to the mutational status of TP53, KRAS, and EGFR. Methods mRNA and miRNA expression was determined using TaqMan assays in 110 early-stage NSCLC patients. TP53, KRAS, and EGFR mutations were assessed by Sanger sequencing. Results NKX2–1 expression was upregulated in never-smokers (P = 0.017), ADK (P