RESUMEN
Comparison of two methods to detect circulating tumor cells (CTC) CytoTrack and CellSearch through recovery of MCF-7 breast cancer cells, spiked into blood collected from healthy donors. Spiking of a fixed number of EpCAM and pan-cytokeratin positive MCF-7 cells into 7.5 mL donor blood was performed by FACSAria flow sorting. The samples were shipped to either CytoTrack or CellSearch research facilities within 48 h, where evaluation of MCF-7 recovery was performed. CytoTrack and CellSearch analyses were performed simultaneously. Recoveries of MCF-7 single cells, cells in clusters, and clusters were determined. The average numbers of MCF-7 cells/cells in clusters/clusters recovered from blood by the CytoTrack and CellSearch methods were 103 ± 5.9/27 ± 7.9/11 ± 3.5 (95 % CI) and 107 ± 4.4/20 ± 7.1/10 ± 3.5, respectively, with no difference between the two methods (p = 0.37/p = 0.23/p = 0.09). Overall, the recovery of CytoTrack and CellSearch was 68.8 ± 3.9 %/71.1 ± 2.9 %, respectively (p = 0.58). In spite of different methodologies, CytoTrack and CellSearch found similar number of CTCs, when spiking was performed with the EpCAM and pan cytokeratin-positive cell line MCF-7. The results suggest that CytoTrack and CellSearch have similar abilities to identify CTC in vitro.
Asunto(s)
Antígenos de Neoplasias/genética , Biomarcadores de Tumor/genética , Neoplasias de la Mama/genética , Moléculas de Adhesión Celular/genética , Células Neoplásicas Circulantes , Antígenos de Neoplasias/química , Biomarcadores de Tumor/química , Neoplasias de la Mama/patología , Moléculas de Adhesión Celular/química , Molécula de Adhesión Celular Epitelial , Femenino , Humanos , Técnicas In Vitro/métodos , Queratinas/química , Queratinas/genética , Células MCF-7 , PronósticoRESUMEN
BACKGROUND: Retracing and biomarker characterization of individual circulating tumour cells (CTCs) may potentially contribute to personalized metastatic cancer therapy. This is relevant when a biopsy of the metastasis is complicated or impossible to acquire. METHODS: A novel disc format was used to map and retrace individual CTCs from breast-cancer patients and nucleated cells from healthy blood donors using the CytoTrack platform. For proof of the retracing concept, CTC HER2 characterization by immunofluorescence was tested. RESULTS: CTCs were detected and enumerated in three of four blood samples from breast-cancer patients and the locations of each individual CTCs were mapped on the discs. Nucleated cells were retraced on seven discs with 96.6%±8.5% recovery on five fields of view on each disc. Shifting of field of view for retracing was measured to 4-29 µm. In a blood sample from a HER2-positive breast-cancer patient, CTC enumeration and mapping was followed by HER2 characterization and retracing to demonstrate downstream immunofluorescence analysis of the CTC. CONCLUSION: Mapping and retracing of CTCs enables downstream analysis of individual CTCs for existing and future cancer genotypic and phenotypic biomarkers. Future studies will uncover this potential of the novel retracing technology.