Generating human prostate cancer organoids from leukapheresis enriched circulating tumour cells.

Background: Circulating tumour cell (CTC)-derived organoids have the potential to provide a powerful tool for personalised cancer therapy but are restrained by low CTC numbers provided by blood samples. Here, we used diagnostic leukapheresis (DLA) to enrich CTCs from patients with metastatic prostate cancer (mPCa) and explored whether organoids provide a platform for ex vivo treatment modelling.
Methods: We prospectively screened 102 patients with mPCa and performed DLA in 40 patients with ≥5 CTCs/7.5 mL blood. We enriched CTCs from DLA using white blood cell (WBC) depletion alone or combined with EpCAM selection. The enriched CTC samples were cultured in 3D to obtain organoids and used for downstream analyses.
Results: The DLA procedure resulted in a median yield of 5312 CTCs as compared with 22 CTCs in 7.5 mL of blood. Using WBC depletion, we recovered 46% of the CTCs, which reduced to 12% with subsequent EpCAM selection. From the isolated and enriched CTC samples, organoid expansion succeeded in 35%. Successful organoid cultures contained significantly higher CTC numbers at initiation. Moreover, we performed treatment modelling in one organoid cell line and identified substantial tumour heterogeneity in CTCs using single cell DNA sequencing.
Conclusions: DLA is an efficient method to enrich CTCs, although the modest success rate of culturing CTCs precludes large scale clinical application. Our data do suggest that DLA and subsequent processing provides a rich source of viable tumour cells. Therefore, DLA offers a promising alternative to biopsy procedures to obtain sufficient number of tumour cells to study sequential samples in patients with mPCa.
Trial Registration Number: NL6019.
Competing Interests: Conflict of interest statement Ronald de Wit has an advisory role and/or received speaker fees from; Sanofi, Merck, Lilly, Roche, Bayer, Janssen, Clovis and research funding (Institutional); Sanofi, Bayer. Stefan Sleijfer is the chair of Center for Personalised Cancer Treatment (CPCT), chair of Dutch Science Agenda Personalized Medicine and SkylineDx. Harmen van de Werken has stock and/or other ownership interests in Cergentis and has received honoraria from Bayer. Martijn Lolkema has an advisory role and/or received speaker fees from; Incyte, Amgen, Janssen Cilag B.V., Bayer, Servier, Roche, Pfizer Sanofi Aventis Netherlands BV, Astellas and has received (Institutional) research funding from Sanofi, JnJ, Merck and Astellas. Wytske van Weerden has received (Institutional) research funding from —Sanofi, Janssen Pharmaceuticals and Bayer.Rui P.L. Neves has an advisory role and/or received speaker fees from; Menarini Silicon Biosystems, Thermo Fisher Scientific, Terumo BCT.Nikolas Stoecklein has received remunerations from Menarini Silicon Biosystems.
(Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)