Genetic alterations of the ATBF1 gene in gastric cancer

Purpose: α-Fetoprotein (AFP)-producing gastric cancers are aggressive tumors with venous and lymphatic invasion and hepatic metastasis. The goal of the present study was to investigate whether somatic changes of the AFP-negative regulator AT motif binding factor-1 (ATBF1) gene are involved in the development or progression of gastric cancers and the production of AFP in gastric cancer cells. Experimental Design: We searched for genetic alterations of the ATBF1 gene by single-strand conformational polymorphism and sequencing methods as well as allelic loss analysis with the microsatellite markers D16S3066 and D16S3139. Immunochemistry for AFP expression in gastric cancer cells was also done. Results: In 81 sporadic gastric cancers, four mutations were detected in seven cases: one was a missense mutation and three were deletions; loss of heterozygosity at the ATBF1 locus was detected in 52.9% of informative samples. Five of the eight cancers with AFP expression showed ATBF1 genetic alterations. Conclusions: These results suggest that genetic alteration of the ATBF1 gene may contribute to the aggressive nature of gastric cancers and the production of AFP in gastric cancer cells.