Efficient isolation and quantification of circulating tumor cells in non-small cell lung cancer patients using peptide-functionalized magnetic nanoparticles

Naixin Liang; Lei Liu; Ping Li; Yuan Xu; Yingshuo Hou; Jiaxi Peng; Yang Song; Zhongxing Bing; Yadong Wang; Yanyu Wang; Ziqi Jia; Xiaoying Yang; Da Li; Huihui Xu; Qian Yu; Shanqing Li; Zhiyuan Hu; Yanlian Yang

doi:10.21037/jtd-20-1026A

Efficient isolation and quantification of circulating tumor cells in non-small cell lung cancer patients using peptide-functionalized magnetic nanoparticles

J Thorac Dis. 2020 Aug;12(8):4262-4273. doi: 10.21037/jtd-20-1026A.

Authors

Naixin Liang¹, Lei Liu¹, Ping Li², Yuan Xu¹, Yingshuo Hou³, Jiaxi Peng², Yang Song¹, Zhongxing Bing¹, Yadong Wang^{1

4}, Yanyu Wang^{1

4}, Ziqi Jia^{1

4}, Xiaoying Yang^{1

4}, Da Li³, Huihui Xu³, Qian Yu³, Shanqing Li¹, Zhiyuan Hu^{2

3

5}, Yanlian Yang^{2

3

5}

Affiliations

¹ Department of Thoracic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
² CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Key Laboratory of Biological Effects of Nanomaterials and Nanosafety, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, China.
³ Nanopep Biotech Co., Beijing, China.
⁴ Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
⁵ University of Chinese Academy of Sciences, Beijing, China.

Abstract

Background: Circulating tumor cells (CTCs) carry a wealth of information on primary and metastatic tumors critical for enhancing the understanding of the occurrence, progression and metastasis of non-small cell lung cancer (NSCLC). However, the low sensitivity of traditional tumor detection methods limits the application of CTCs in the treatment and disease surveillance of NSCLC. Therefore, CTCs isolation and detection with high sensitivity is highly desired especially for NSCLC patients, which is significant because of high occurrence and mortality. While it is very challenging because of the lower expression of CTC positive biomarkers such as epithelial cell adhesion molecules and cytokeratins (EpCAM and CKs), herein we report a method based on peptide-functionalized magnetic nanoparticles with high CTC capture efficiency, which demonstrates superiority in NSCLC clinical applications.

Methods: For analysis and comparison of the peptide-functionalized magnetic nanoparticles (TumorFisher, Nanopep Corp.) and the antibody-modified magnetic beads (CellSearch, Janssen Diagnostics, LLC), two NSCLC cell lines, A549 and NCI-H1975 were chosen to measure the binding affinity and capture efficiency. In order to compare the effect of the clinical application of these two detection systems, 7 early stage patients with NSCLC were enrolled in this study. To further explore the clinical utility of CTC counting in different stages, 81 NSCLC patients in stage I-IV were enrolled for CTC enumeration and statistical analysis.

Results: The binding affinities of the recognition peptide to A549 and NCI-H1975 are 76.7%±11.0% and 70.1%±4.8%, respectively, which is similar with the positive control group (anti-EpCAM antibodies). CTCs were captured in 5/7 (71.4%) of early stage NSCLC patients with NSCLC in TumorFisher system, which is higher than CellSearch, and the false negative of TumorFisher is much lower than CellSearch. In a larger clinical cohort, the CTC numbers of NSCLC patients varied in different stages and the overall detection rate of TumorFisher was 59/81 (72.8%), with the similar proportion in stage I (21/29, 72.4%), II (17/22, 77.3%) and III (16/21, 76.2%).

Conclusions: Highly efficient CTC isolation technique based on peptide-magnetic nanoparticles was firstly applied in NSCLC patients. Compared with the antibody-based the technique, the higher CTC detection rates (71.4%) in NSCLC patient blood samples were demonstrated for the patients in different stages, I-IV, especially in early stages. This indicates the feasibility of the clinical utility of this new technique in early stage screening, prognosis and therapy evaluation of NSCLC.

Keywords: circulating tumor cell (CTC); liquid biopsy; nanoparticle; non-small cell lung cancer (NSCLC); peptide (Pep).