Prognostic impact of FOXF1 polymorphisms in gastric cancer patients
A recent genome-wide association study identified seven single-nucleotide polymorphisms (SNPs) in region 16q24, near the Forkhead box-F1 (FOXF1) gene, which confer susceptibility to esophageal adenocarcinoma. We examined whether these SNPs are associated with clinical outcomes in gastric cancer (GC) patients in Japan and the United States. A total of 362 patients were included in this study: 151 Japanese GC patients treated with first-line S1 plus CDDP (training cohort) and 211 GC patients from Los Angeles County (LAC; validation cohort). Genomic DNA was isolated from whole blood or tumor tissue and analyzed by PCR-based direct DNA sequencing. Cox proportional hazard regression analyses were used to assess relationships between FOXF1 SNPs and progression-free survival (PFS) and overall survival (OS). FOXF1 rs3950627 was significantly associated with survival in both the training and validation cohorts. Japanese patients with the C/C genotype had a longer PFS (median 8.2 vs 5.3 months, hazard ratio (HR) 1.44, P = 0.037) and OS (median 16.4 vs 12.2 months, HR 1.44, P = 0.043) compared to patients with any A allele. Similarly, LAC patients with the C/C genotype had improved OS (3.9 vs 2.3 years, HR 1.5, P = 0.022). Subgroup analyses showed these associations were specific to male patients and primary tumor subsite. Our findings suggest that FOXF1 rs3950627 might be a promising prognostic marker in GC patients.