Serum Fork-Head Box D3 (FOXD3) Expression Is Down-Regulated in and Associated with Diagnosis of Patients with Non-Small Cell Lung Cancer

BACKGROUND: The aim of this study was to detect the expression of fork-head box D3 (FOXD3) and investigate its diagnostic value in patients with non-small cell lung cancer (NSCLC). MATERIAL/METHODS: The relative expression of FOXD3 at mRNA and protein levels was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting analysis, respectively. Chi-square test was used to explore the relevance of FOXD3 expression with clinical features of NSCLC patients. A receiver operating characteristic (ROC) curve was built to estimate the diagnostic value of FOXD3 in distinguishing NSCLC patients from healthy controls. RESULTS: Serum FOXD3 expression was weakly expressed in NSCLC patients compared to the controls at mRNA and protein levels (P<0.001) and low FOXD3 expression was positively correlated with TNM stage, lymph node metastasis, and differentiation. The ROC curve indicated that FOXD3 acts as a diagnostic bio-marker for NSCLC patients, with an AUC of 0.826 corresponding to a sensitivity of 77.1% and a specificity of 74.6%, and an optimal cutoff point of 2.38. CONCLUSIONS: Decreased expression of serum FOXD3 was observed in NSCLC patients, and it was found to be a potential molecular marker for the diagnosis of NSCLC.