Overexpression of the Wilms' Tumor Gene WT1 in Esophageal Cancer

Abstract

Background: The Wilms' tumor gene WT1 is overexpressed in various kinds of solid cancers. However, it remains unclear whether WT1 is expressed in esophageal squamous cell carcinoma. Materials and Methods: Expression of the WT1 gene was examined by real-time RT-PCR in 12 esophageal squamous cell carcinoma (ESCC) and by immunohistochemistry in 9 of these 12 and another 29. Results: Real-time RT-PCR showed that the WT1 mRNA was overexpressed in all of the 12 ESCC examined. Immunohistochemical analysis showed that the WT1 protein was overexpressed in ESCC cells in 36 (95%) of the 38 examined. Furthermore, expression of the WT1 protein was examined in 20 esophageal squamous dysplasia. The WT1 protein was overexpressed in 5 (45%) out of 11 mild dysplasia and in 8 (89%) out of 9 moderate to severe dysplasia. Conclusion: These results may indicate an important role of the WT1 gene in the tumorigenesis of ESCC.