The GI-101 human breast tumour xenograft-line is unique in that it spo
ntaneously metastasises to the lungs of athymic murine hosts from subc
utaneous trochar implants. Both tumour and lung metastases are positiv
e for normal human breast tissue markers. GI-101 also is positive for
the p53 antigen but negative for the c-erbB-2 oncogene.