SLC39A4 as a Novel Prognosis Marker Promotes Tumor Progression in Esophageal Squamous Cell Carcinoma

Background: Solute carrier family 39 member 4 (SLC39A4) has been reported to play an oncogenic role in several cancers. However, the role of SLC39A4 in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, we aimed to explore the clinical significance and function of SLC39A4 in ESCC. Methods: The Cancer Genome Atlas and Gene Expression Omnibus databases were analyzed to assess the level of SLC39A4 in ESCC. The expression level of SLC39A4 was measured by RT-qPCR and immunohistochemistry in a cohort of 73 patients aged 45-65 years with ESCC. Kaplan-Meier analysis was used to identify the correlation between SLC39A4 and the prognosis of ESCC patients. In vitro experiments were conducted to explore the biological function of SLC39A4 in ESCC cell line TE-1 and TE-10. Results: The mRNA level of SLC39A4 was significantly enhanced in ESCC specimens, which was in line with the outcome of online databases analysis. Moreover, the aberrant expression of SLC39A4 was positively correlated with clinical stage, T categories and lymph node metastasis. Kaplan-Meier analysis indicated that elevated SLC39A4 expression predicted poor prognosis of patients with ESCC. Furthermore, the in vitro experiments showed that SLC39A4 knockdown not only impaired the proliferation and motility capacities of ESCC cells but also enhanced the sensitivity to cisplatin treatment. Conclusion: Our findings suggest that SLC39A4 could serve as a novel prognosis biomarker to promote ESCC progression; however, the mechanism of SLC39A4 in ESCC remains to be further explored.