Detection of circulating carcinoma cells by telomerase activity.
Telomerase has been shown to be a marker of epithelial cancer cells. We developed a method that allows the detection of circulating carcinoma cells in the blood of cancer patients. Circulating epithelial cells are harvested from peripheral blood mononuclear cells by immunomagnetic separation using BerEP4-coated beads. A telomeric repeat amplification protocol (TRAP)-ELISA is then used to measure telomerase in harvested epithelial cells. This method is specific and sensitive as demonstrated by experiments using BerEP4-positive and negative cell lines. Whereas we never found telomerase activity in harvested epithelial cells (HEC) samples from 30/30 healthy donors, we have detected telomerase activity in HEC from 11/15 (73%) patients with stage IIIB or IV non-small cell lung cancer (NSCLC) patients and from 8/11 (72%) stage C or D (Dukes classification) colon cancer patients. This non-invasive method could be of great value as a diagnostic or prognostic marker, or for monitoring cancer progression.
Laboratoire de RadioPathologie, DRR/DSV CEA BP6, Fontenay-aux-Roses, 92265, France.
L R
LR
Gauthier
C
C
Granotier
J C
JC
Soria
S
S
Faivre
V
V
Boige
E
E
Raymond
F D
FD
Boussin
D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D002277:Carcinoma / Q000175:diagnosis* / Q000473:pathology; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000473:pathology; D004796:Clinical Enzyme Tests / Q000379:methods*; D003110:Colonic Neoplasms / Q000175:diagnosis; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D008175:Lung Neoplasms; D008875:Middle Aged; D012680:Sensitivity and Specificity; D019098:Telomerase / Q000097:blood*; D014407:Tumor Cells, Cultured
D014408:Biomarkers, Tumor; D019098:Telomerase