Gene amplification in gastric and esophageal adenocarcinomas.
In a United States series of 28 gastric/esophageal adenocarcinomas of poorly to moderately differentiated histopathology, we detected gene amplification in 21% of the tumors. Using the modified DNA in-gel renaturation assay to detect down to 7-8 copies of amplified DNA sequences, we identified 3 gastric tumors with amplified DNA sequences and confirmed by Southern hybridization analysis that HER-2/neu was amplified greater than 5-fold in these specimens. Immunohistochemical staining of tumor tissue sections with p185 HER-2/neu antibodies demonstrated that only the 3 gastric adenocarcinomas with corresponding HER-2/neu gene amplification displayed membrane immunoreactivity. Amplification of c-met was identified in 2 tumors, and this was the first study to assay for multiple copies of this protooncogene in fresh gastric tumor tissues. Amplification of c-erbB was observed in one tumor, and no evidence for amplification of int-2 was obtained in this series of adenocarcinomas.
Houldsworth
J
J
Laboratory of Cancer Genetics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021.
Cordon-Cardo
C
C
Ladanyi
M
M
Kelsen
D P
DP
Chaganti
R S
RS
D000230:Adenocarcinoma / Q000235:genetics*; D015139:Blotting, Southern; D004273:DNA, Neoplasm / Q000032:analysis; D004938:Esophageal Neoplasms / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics*; D006801:Humans; D009857:Oncogenes; D013274:Stomach Neoplasms / Q000235:genetics*
D004273:DNA, Neoplasm