Low level of FOXL1 indicates a worse prognosis for gastric cancer patients

The aim of this study was to detect forkhead box L1 (FOXL1) expression in gastric cancer (GC) and to analyze its association with the prognosis of GC patients. Immunohistochemical staining, Western blotting, and quantitative reverse transcriptase polymerase chain reaction were performed to detect FOXL1 tissue expression in 109 GC patients. Clinicopathological characteristics and survival data were retrospectively analyzed to discover the clinical importance of FOXL1 expression. The chi-square test was used to analyze the relationship between FOXL1 expression and the clinicopathological characteristics. Survival curves were plotted by using the Kaplan-Meier method and compared using the log-rank test. Survival data were evaluated using univariate and multivariate Cox regression analyses. The expression of FOXL1 messenger RNA (mRNA) was significantly higher in adjacent normal samples than in the tumor tissues (P = 0.043). Clinicopathological analysis showed that FOXL1 expression was significantly correlated with depth of invasion (P = 0.017), lymph node metastasis (P = 0.019), and distant metastasis (P = 0.047). FOXL1-negative as opposed to the FOXL1-positive patients had lower 5-year overall survival (14.06 vs. 37.78 %, P < 0.001). Multivariate analysis suggested that FOXL1 expression might be an independent prognostic indicator (hazard ratio = 0.307, 95 % confidence interval, 0.187-0.505; P < 0.001) for GC patients. In conclusion, our findings provide evidence that FOXL1 might serve as a candidate tumor suppressor and a potential prognostic biomarker for GC.