Polymorphisms in Epithelial-Mesenchymal Transition-Related Genes and the Prognosis of Surgically Treated Non-small Cell Lung Cancer

Background: This study was conducted to determine whether single-nucleotide polymorphisms (SNPs) in EMT-related genes may influence the prognosis of NSCLC after surgery. Methods: There were 88 SNPs in EMT-related genes evaluated in a discovery set of 376 patients who underwent curative surgery for NSCLC. Significantly, 14 SNPs were evaluated in a validation set of 428 patients. Luciferase assay and RT-PCR were conducted to examine functional relevance of polymorphisms. Results: Fourteen SNPs that were associated with survival outcomes in a discovery set were selected for validation. Among those, two SNPs (FOXF2 rs1711972A>C and HEYL rs784621G>A) were replicated in a validation study. In combined analysis, FOXF2 rs1711972 AC+CC genotype was associated with significantly better overall survival (OS) and disease-free survival (DFS) compared with AA genotype (adjusted hazard ratio [aHR] for OS = 0.67, 95% confidence interval [CI] 0.51–0.88, P = 0.004; and aHR for DFS = 0.77, 95% CI 0.62–0.95, P = 0.01). HEYL rs784621 AA genotype exhibited a significantly worse OS compared with GG+GA genotype (aHR for OS = 2.65, 95% CI 1.63–4.31, P = 8 × 10⁻⁵). FOXF2 rs1711972C allele had a significantly increased promoter activity than rs1711972A allele (P = 0.01), and HEYL rs784621A allele had a significantly lower promoter activity than rs784621G allele (P = 0.004). FOXF2 rs1711972A>C was significantly associated with increased FOXF2 mRNA expression. Conclusions: FOXF2 rs1711972A>C and HEYL rs784621G>A were associated with survival outcomes of surgically treated NSCLC. These SNPs may help to identify patients at high risk of poor disease outcomes.