Detection of circulating tumor cells in breast cancer with a refined immunomagnetic nanoparticle enriched assay and nested-RT-PCR

Early detection of circulation tumor cells (CTCs) in breast cancer patients has great clinical relevance. Currently, immunomagnetic microparticles enriched assays require Fe3O4 inner cores, making it difficult to improve sensitivity. In this study, we prepared magnetic nanoparticles with carbon-coated pure iron (Fe@C) acted as the core, Conjugating with EpCAM monoclonal antibody for immunomagnetic nanoparticles(IMPs). IMPs were used in conjunction with immunocytochemistry (ICC) to develop a refined immunomagnetic nanoparticles enriched assay (IMPEA) for detection of circulating tumor cells (CTCs) in breast cancer patients. Compared with nested RT-PCR, this method achieved the same sensitivity, but with a significantly reduced false-positive rate. This method will help find hidden micrometastases, establish clinical stage, and guide individual treatment post-surgery, suggesting potentially significant value in the clinic.From the Clinical EditorThis team of investigators prepared magnetic nanoparticles with carbon-coated pure iron as core and conjugated them with EpCAM monoclonal antibody to form immunomagnetic nanoparticles for circulating tumor cell (CTC) detection. Compared with nested RT-PCR, this method achieved the same sensitivity, but with a significantly reduced false-positive rate, paving the way to the development of a tool that enables enhanced detection of micrometastases and post-surgical treatment monitoring.

Graphical AbstractThese immunomagnetic nanoparticles (IMPs) were used in conjunction with immunocytochemistry (ICC) and to develop a refined immunomagnetic nanoparticle enrichment assay for detection of circulating tumor cells (CTCs) in breast cancer patients. The assay was compared with nested reverse transcription polymerase chain reaction (RT-PCR) using detection of cytokeratin 19 (CK19) mRNA and human mammaglobin (hMAM) mRNA. The human breast carcinoma cell line, MCF-7, was utilized for sensitivity and specificity evaluation. The peripheral blood was collected from 78 breast cancer patients, 25 patients with benign breast lesions, and 25 healthy volunteers. The CTCs were detected with the assay. The IMPs had an average size of 56 nm, and the antibody concentration was 108.6 μg/mg. One breast cancer cell could be detected in 5 × 107 peripheral blood mononuclear cells. Compared with nested RT-PCR, this method achieved the same sensitivity, but with a significantly reduced false-positive rate. A refined immunomagnetic nanoparticle method shows the same sensitivity for circulating tumor cells in breast cancer patients, but greatly improved specificity compared with nested RT-PCR. This method will help find hidden micrometastases, establish clinical stage, and guide individual treatment post-surgery, suggesting potentially significant value in the clinic.Figure optionsDownload high-quality image (152 K)Download as PowerPoint slide