Assessing sequential oncogene amplification in human breast cancer.
Studies of amplification and/or overexpression of c-myc, HER-2/neu, and H-ras in breast cancer have shown that each is associated with a poor prognosis. The purpose of this study was to explore the possibility that there is a preferred sequence of amplification of these oncogenes in breast cancer. The frequencies of amplification and patterns of co-amplification of c-myc, HER-2/neu, and H-ras were studied in a group of 84 breast cancers. The data suggested a preferred sequence of amplification that consisted of c-myc amplification-HER-2/neu amplification-H-ras amplification. This model was supported by loglinear analysis. In addition, the levels of amplification of JC-A, a DNA fragment newly isolated from a patient with advanced breast cancer, were studied in 61 of these cases. The data suggested that JC-A amplification occurred early. Loglinear analysis supported a model in which JC-A amplification occurred either before or after c-myc amplification but was unrelated to Her-2/neu or ras amplification.
Laboratory of Cancer Cell Biology and Genetics, Allegheny-Singer Research Institute, Pittsburgh, PA 15212-4772, USA.
L E
LE
Janocko
J F
JF
Lucke
D W
DW
Groft
K A
KA
Brown
C A
CA
Smith
A A
AA
Pollice
S G
SG
Singh
R
R
Yakulis
R J
RJ
Hartsock
S E
SE
Shackney
D000230:Adenocarcinoma / Q000235:genetics*; D001943:Breast Neoplasms / Q000235:genetics*; D003110:Colonic Neoplasms; D005260:Female; D005784:Gene Amplification / Q000235:genetics*; D016259:Genes, myc / Q000235:genetics; D006801:Humans; D016014:Linear Models; D009857:Oncogenes / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics; D014407:Tumor Cells, Cultured / Q000502:physiology
D016283:Proto-Oncogene Proteins p21(ras); D018719:Erb-b2 Receptor Tyrosine Kinases; C501009:HRAS protein, human