%0 Journal Article %J Mol Cell Biol %D 1987 %T Amplification of the neu (c-erbB-2) oncogene in human mammmary tumors is relatively frequent and is often accompanied by amplification of the linked c-erbA oncogene. %A van de Vijver, M %A van de Bersselaar, R %A Devilee, P %A Cornelisse, C %A Peterse, J %A Nusse, R %P 2019–2023 %V 7 %X We investigated alterations in the structure and expression of oncogenes in mammary tumors and mammary tumor-derived cell lines. In 16 of 95 samples, we detected amplification of the human neu oncogene, also known as c-erB-2, accompanied by overexpression in the tumors from which intact RNA could be isolated. In 10 of these DNAs, the linked oncogene c-erbA was also amplified, whereas another gene on human chromosome 17, p53, was present in normal copy numbers. Overexpression of c-erbA could not be detected in the tumors analyzed. The relatively high frequency of neu amplification points to a functional role in human breast cancer. Coamplification of the c-erbA oncogene could contribute to this disease as well but is most likely fortuitous. %8 May