Increased expression of FOXD1 is associated with cervical node metastasis and unfavorable prognosis in oral squamous cell carcinoma

Background Previous studies suggest that FOXD1 is involved in tumorigenesis and closely related to the patients' poor outcome in human cancer. However, its expression pattern in primary oral squamous cell carcinoma (OSCC) remains uncovered. In this study, we tried to explore the expression pattern of FOXD1 and its clinicopathological significance in primary OSCC. Methods Data mining and analysis on FOXD1 mRNA expression in OSCC samples were performed using publicly available databases. Its protein expression was supervised by immunohistochemistry in a retrospective cohort containing 58 primary OSCC samples. Furthermore, the potential associations between FOXD1 expression and various clinicopathological characteristics and patients' survival were further investigated. Results Bioinformatic analysis indicated that FOXD1 mRNA abundance was obviously up-regulated in OSCC cohorts. Immunohistochemical staining results showed that FOXD1 protein was significantly up-regulated in OSCC specimens as compared to normal counterparts and its aberrant up-regulation was remarkably related to cervical lymph node metastasis (P = .0198) and decreased overall survival (P = .0281) and disease-free survival (P = .0312). Both univariate and multivariate Cox regression analysis further revealed the expression pattern of FOXD1 as an independent prognostic factor for overall survival of patients. Conclusion Taken together, these findings indicate that the aberrant up-regulation of FOXD1 is related to cervical node metastasis and unfavorable prognosis in OSCC and it also may play a key role during OSCC tumorigenesis and regard as a novel diagnostic and prognostic biomarker for OSCC.