Diagnostic leukapheresis reveals distinct phenotypes of NSCLC circulating tumor cells.
Authors
Lisa-Marie Rieckmann, Michael Spohn, Lisa Ruff, David Agorku, Lisa Becker, Alina Borchers, Jenny Krause, Roisin O’Reilly, Jurek Hille, Janna-Lisa Velthaus-Rusik, Niklas Beumer, Armin Günther, Lena Willnow, Charles D Imbusch, Peter Iglauer, Ronald Simon, Sören Franzenburg, Hauke Winter, Michael Thomas, Carsten Bokemeyer, Nicola Gagliani, Christian F Krebs, Martin Sprick, Olaf Hardt, Sabine Riethdorf, Andreas Trumpp, Nikolas H Stoecklein, Sven Peine, Philipp Rosenstiel, Klaus Pantel, Sonja Loges, Melanie Janning
Year of publication
2024Journal
MOL CANCERVolume
23Issue
1Abstract
Background
Circulating tumor cells (CTCs) hold immense promise for unraveling tumor heterogeneity and understanding treatment resistance. However, conventional methods, especially in cancers like non-small cell lung cancer (NSCLC), often yield low CTC numbers, hindering comprehensive analyses. This study addresses this limitation by employing diagnostic leukapheresis (DLA) to cancer patients, enabling the screening of larger blood volumes. To leverage DLA’s full potential, this study introduces a novel approach for CTC enrichment from DLAs.
Methods
DLA was applied to six advanced stage NSCLC patients. For an unbiased CTC enrichment, a two-step approach based on negative depletion of hematopoietic cells was used. Single-cell (sc) whole-transcriptome sequencing was performed, and CTCs were identified based on gene signatures and inferred copy number variations.
Results
Remarkably, this innovative approach led to the identification of unprecedented 3,363 CTC transcriptomes. The extensive heterogeneity among CTCs was unveiled, highlighting distinct phenotypes related to the epithelial-mesenchymal transition (EMT) axis, stemness, immune responsiveness, and metabolism. Comparison with sc transcriptomes from primary NSCLC cells revealed that CTCs encapsulate the heterogeneity of their primary counterparts while maintaining unique CTC-specific phenotypes.
Conclusions
In conclusion, this study pioneers a transformative method for enriching CTCs from DLA, resulting in a substantial increase in CTC numbers. This allowed the creation of the first-ever single-cell whole transcriptome in-depth characterization of the heterogeneity of over 3,300 NSCLC-CTCs. The findings not only confirm the diagnostic value of CTCs in monitoring tumor heterogeneity but also propose a CTC-specific signature that can be exploited for targeted CTC-directed therapies in the future. This comprehensive approach signifies a major leap forward, positioning CTCs as a key player in advancing our understanding of cancer dynamics and paving the way for tailored therapeutic interventions.