Characterization and enumeration of cells secreting tumor markers in the peripheral blood of breast cancer patients.
In the process of metastasis, malignant cells are released from the primary tumor and migrate to specific organs via the lymphatic and blood circulation systems. These circulating tumor cells have been characterized by immunochemistry, the reverse transcription-polymerase chain reaction, and flow cytometry. Using the MCF-7 breast cancer cell line, we have developed a two-color ELISPOT assay to detect cells secreting cathepsin D protease and MUC1 glycoprotein, markers associated with the risk of metastases in breast cancer. The threshold of detection of this ELISPOT assay was one cathepsin D- or MUC1-secreting MCF7 cell per 5 ml of control blood. In 16 patients with breast carcinoma metastases, 1 to 1940 cathepsin D- or MUC1-secreting cells per 2x10(7) PBMC were enumerated, whereas none were found in 11 controls. Moreover, in six patients 6-60% of MUC1-secreting cells also expressed the CXCR4 chemokine receptor, which is involved in the homing of metastatic breast cancer cells. The ELISPOT assay described here allowed us to enumerate cathepsin D- and/or MUC1-secreting cells in the MCF-7 cell line and in the peripheral blood of patients with disseminated breast cancer. The combination of the ELISPOT assay and CXCR4-positive cell sorting identified subsets of MUC1-secreting cells in the peripheral blood of these patients.
Alix-Panabières
Catherine
C
Laboratoire de Virologie, Hôpital Lapeyronie, av. du Doyen G. Giraud, 34295 Montpellier, France.
Brouillet
Jean-Paul
JP
Fabbro
Michel
M
Yssel
Hans
H
Rousset
Thérèse
T
Maudelonde
Thierry
T
Choquet-Kastylevsky
Genevieve
G
Vendrell
Jean-Pierre
JP
D014408:Biomarkers, Tumor / Q000097:blood*; D001943:Breast Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D002402:Cathepsin D / Q000097:blood*; D002452:Cell Count; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D005260:Female; D006801:Humans; D018396:Mucin-1 / Q000097:blood*; D009362:Neoplasm Metastasis / Q000175:diagnosis; D019718:Receptors, CXCR4 / Q000378:metabolism; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D018396:Mucin-1; D019718:Receptors, CXCR4; D002402:Cathepsin D