A Microwell‐Assisted Multiaptamer Immunomagnetic Platform for Capture and Genetic Analysis of Circulating Tumor Cells

Abstract

Detection of circulating tumor cells (CTCs) in peripheral blood is of paramount significance for cancer diagnosis, progress evaluation, and individualized therapy. However, the rareness and heterogeneity of CTCs introduces significant challenges in the capture of cancer cells as well as downstream genetic analysis. In this work, a microwell‐assisted multiaptamer immunomagnetic platform (MMAIP) is proposed for highly efficient capture of CTCs with minimum influence of heterogeneity. Assisted by a microwell chip, the purity of CTCs is greatly improved, thus meeting the requirement of downstream gene analysis. This is, as far as is known, the first aptamer based platform enabling mutation analysis of the captured CTCs from cancer patients, which will contribute to the practical application of aptamers in clinics.

The Potential of Aptamer-Mediated Liquid Biopsy for Early Detection of Cancer

“…In addition, these aptamers were further utilized for a bioluminescent solid-phase sandwich-type microassay to detect lung tumor elements circulating in the blood [ 131 ]. Fang’s group introduced a cocktail of aptamer-modified magnetic nanoparticles (apt-MNPs) to capture heterogeneous CTC populations [ 132 ]. A microwell chip was used to improve the CTC purity for downstream applications.…”

Microfluidic Single‐Cell Omics Analysis

“…Once captured, cells are hardly washed away due to the limited fluid impact above microwells. Its merits, including simple microfabrication, well‐shaped structure, convenient operation without pumps, make it a widespread platform for high‐throughput single‐cell culture and in situ analysis . Additionally, the roofless microwell structure permits rapid and direct sample retrieval, and flexible capping manipulation endows the capability for secretion capture and detection .…”

Advances in Oligonucleotide Aptamers for NSCLC Targeting

“…An interesting feature of the system was the possibility to recover the captured CTCs upon treatment with a nuclease solution, allowing the isolation of CTCs for further functional and molecular analyses. Nevertheless, the method showed some limitations in the release of captured CTCs when, instead of artificial spiked samples, real patient blood samples were used, probably because the presence of blood components and to the sticky nanowires utilized [ 32 ].…”

“…To overcome these disadvantages, the authors have recently developed a new method to exploit the synergistic effect of the aptamer cocktails. The assay used aptamer-coated magnetic beads for the capture of CTCs and a subsequent microwell chip-assisted purification step of the obtained cell suspension [ 32 ]. The microwell-assisted multiaptamer immunomagnetic platform (MMAIP) developed was tested for the isolation of CTCs from NSCLC patients’ blood samples collected after chemotherapy treatment.…”

“…The microwell-assisted multiaptamer immunomagnetic platform (MMAIP) developed was tested for the isolation of CTCs from NSCLC patients’ blood samples collected after chemotherapy treatment. Using modified magnetic nanoparticles with two aptamers (apt1 and apt2) which recognize A549 and cisplatin-resistant A549D cells, respectively, the authors achieved CTC capture and gene analysis from clinical patients’ blood samples [ 32 ]. Thus, by means of this noninvasive method, key supplementary information for patient’s diagnosis, prognosis and treatment response, as well as for real time characterization of CTCs was obtained.…”