title: Intratumoral heterogeneity for amplified genes in human breast carcinoma.
abstract: Intratumoral heterogeneity was studied in human breast cancer by examining separate tumor lesions of individual patients. Tumor samples were obtained from each patient by fine-needle biopsies from 2 to 4 separate tumor lesions. We used a semi-quantitative PCR to distinguish between samples with gene amplification and single gene copy samples. Five genes were analyzed in each biopsy: MDR-1, dihydrofolate reductase, thymidylate synthase, c-erb-B2 and int-2. Three groups of patients were examined: those awaiting initiation of treatment; those receiving first-line endocrine therapy; and those receiving second-line endocrine treatment. A pattern of intratumoral heterogeneity for gene amplification was clearly apparent. The frequency of amplification was lowest before initiating therapy and highest in patients receiving second-line treatment (p = 0.023).
authors.affiliation: Radiumhemmet, Karolinska Hospital, Stockholm, Sweden.
authors.forename: U
authors.initials: U
authors.lastname: Lönn
authors.forename: S
authors.initials: S
authors.lastname: Lönn
authors.forename: B
authors.initials: B
authors.lastname: Nilsson
authors.forename: B
authors.initials: B
authors.lastname: Stenkvist
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D001706:Biopsy; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics; D004351:Drug Resistance; D004586:Electrophoresis; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D051518:Fibroblast Growth Factor 3; D005346:Fibroblast Growth Factors / Q000235:genetics; D005784:Gene Amplification; D014644:Genetic Variation; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011374:Progesterone / Q000627:therapeutic use; D011518:Proto-Oncogene Proteins / Q000235:genetics; D018719:Erb-b2 Receptor Tyrosine Kinases; D013629:Tamoxifen / Q000627:therapeutic use; D013739:Testosterone / Q000627:therapeutic use; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D013940:Thymidylate Synthase / Q000235:genetics
chemical_list: D004273:DNA, Neoplasm; D066246:ErbB Receptors; D051518:Fibroblast Growth Factor 3; D005346:Fibroblast Growth Factors; D011374:Progesterone; D011518:Proto-Oncogene Proteins; D018719:Erb-b2 Receptor Tyrosine Kinases; D013629:Tamoxifen; D013739:Testosterone; D013762:Tetrahydrofolate Dehydrogenase; D013940:Thymidylate Synthase; C496444:FGF3 protein, human