Expression of the ets-1 proto-oncogene in human pancreatic carcinoma.

The proto-oncogene, ets-1, is a transcription factor that controls the expression of a number of genes involved in extracellular matrix remodeling. It might play a role in cell migration and tumor invasion. To elucidate the involvement of Ets-1 in human pancreatic carcinoma, we performed immunohistochemical analysis on tissue from 10 normal pancreases and 103 cases of pancreatic carcinoma. We compared the degree of Ets-1 expression. In addition, among the pancreatic carcinomas, we compared Ets-1 expression in relation to the differentiation, lymph node metastasis and the depth of invasion of the carcinoma. Ets-1 was expressed faintly in normal pancreatic tissue. Among the 103 cases of pancreatic carcinoma, 83 (80.5%) showed positive staining for the Ets-1 protein. Histologically, papillary carcinoma, well-differentiated adenocarcinoma, and moderately differentiated adenocarcinoma expressed high positivity for Ets-1. In contrast, poorly differentiated adenocarcinoma expressed relatively weak positivity for Ets-1. Ets-1 expression had no relation to the presence of lymph node metastasis, tumor size, prognosis, or tumor-node-metastasis stage in pancreatic carcinomas. In situ hybridization also confirmed the presence of ets-1 mRNA in pancreatic carcinomas. We detected expression of ets-1 mRNA in three human pancreatic carcinoma cell lines by the reverse transcription-polymerase chain reaction method. These findings suggest that Ets-1 expression is related to the carcinogenesis of human pancreatic carcinoma, but its relationship to tumor progression is unclear.