title: Molecular detection of telomerase-positive circulating epithelial cells in metastatic breast cancer patients.
abstract: The detection of circulating tumor cells and micrometastases may have important therapeutic and prognostic implications. Telomerase is a hallmark of cancer and is absent from normal epithelial cells. The aim of this study was to use telomerase activity as a molecular marker for the detection of cancer cells in blood of patients with breast cancer. Blood samples were collected from 25 women with stage IV breast cancer and 9 healthy volunteers. Peripheral blood mononuclear cells were isolated by using Ficoll/Hypaque. Immunomagnetic beads coated with an epithelial-specific antibody (BerEP4) were used to harvest epithelial cells from peripheral blood mononuclear cells. Telomerase activity was detected in harvested epithelial cells (HECs) using two different telomerase-PCR-ELISA methods. HECs from blood samples of 21 of 25 (84%) patients with breast cancer were telomerase positive. Telomerase activity was undetectable in HECs from the nine healthy volunteers, demonstrating the specificity of the association between telomerase activity in HECs and stage IV breast cancer. Thus, determination of telomerase activity in HECs appears to be a sensitive, specific, and noninvasive approach for detecting circulating epithelial cancer cells in patients with metastatic breast cancer. This method could be of great value in monitoring the cancer cell proliferation during chemotherapy. This study should be now extended to patients with early-stage breast cancer to investigate the role of telomerase expression by HECs and to evaluate its prognostic value.
authors.affiliation: Laboratoire de Radiobiologie et Oncologie, DRR/DSV, CEA, Fontenay-aux-Roses, France.
authors.forename: J C
authors.initials: JC
authors.lastname: Soria
authors.forename: L R
authors.initials: LR
authors.lastname: Gauthier
authors.forename: E
authors.initials: E
authors.lastname: Raymond
authors.forename: C
authors.initials: C
authors.lastname: Granotier
authors.forename: L
authors.initials: L
authors.lastname: Morat
authors.forename: J P
authors.initials: JP
authors.lastname: Armand
authors.forename: F D
authors.initials: FD
authors.lastname: Boussin
authors.forename: L
authors.initials: L
authors.lastname: Sabatier
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood / Q000201:enzymology / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000097:blood / Q000201:enzymology / Q000473:pathology*; D004273:DNA, Neoplasm / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000201:enzymology; D005260:Female; D006801:Humans; D018189:Immunomagnetic Separation; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009363:Neoplasm Proteins / Q000097:blood* / Q000235:genetics / Q000276:immunology; D009367:Neoplasm Staging; D009360:Neoplastic Cells, Circulating / Q000737:chemistry*; D014411:Neoplastic Stem Cells / Q000201:enzymology*; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D019098:Telomerase / Q000097:blood* / Q000235:genetics / Q000276:immunology
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; D019098:Telomerase