Patient-derived, three-dimensional spheroid cultures provide a versatile translational model for the study of organ-confined prostate cancer
To generate and characterize 3D spheroid suspension cultures from radical prostatectomy (RP) specimens as a versatile model system for organ-confined prostate cancer (PCa).
Cancerous tissue samples from RP specimens were excised by a uropathologist. Preparation of 3D spheroids was done by mechanical disintegration and limited enzymatic digestion followed by serial filtration through 100 μm- and 40 μm-cell strainers. Thereafter, spheroids were cultured in a modified stem cell medium and characterized by a live/dead assay, whole-spheroid immunohistochemistry (IHC; CK5, CK8, AMACR, PSA, Ki67, AR, αSMA, Vimentin, E-Cadherin) and PSA-measurements in culture medium. Furthermore, their response to pharmaceutical treatment with docetaxel, bicalutamide, enzalutamide and abiraterone was tested.
173 RP cases were included. The median preoperative PSA-level was 16.12 ng/ml [range 0.99;345], the median Gleason score was 7b [6;10]. 64 cases were excluded due to low tumor content in frozen sections (43) or to insufficient spheroid formation (21). In the remaining 109 cases, spheroids formed successfully and stayed viable for up to several months. IHC analysis revealed AR-, CK8-, and AMACR-positivity in nearly all cases, while CK5-positive cells were detectable only occasionally as were α-SMA and Vimentin. E-Cadherin was positive in most cases. Furthermore, spheroids proved to be amenable to cryopreservation. While abiraterone had no effect and docetaxel only a moderate effect, spheroid viability was markedly reduced upon bicalutamide and enzalutamide treatment.
Multicellular 3D spheroids can be generated from patient-derived RP tissue samples and serve as an innovative in vitro model of organ-confined PCa.
Keywords3D In vitro model Organ-confined Organoid Prostate cancer Spheroid culture
We are grateful to Maria Link, Helga Angeli, Gullan Hebel-Klebsch and Alexander Vogt for excellent technical assistance. We thank Andrea Hasenfus (Institut für Pathologie, St. Vincentius-Kliniken Karlsruhe) for her help during the initial phase of the project and Sebastian Hölters for his help with the immunohistochemistry and the cell culture assays. This work was supported by grants from HOMFOR (Homburger Forschungsförderung) to MSa.
This study was funded by a HOMFOR (Homburger Forschungsförderung) Grant to Matthias Saar.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest to report.
Informed consent for the use of tissue samples from their radical prostatectomy specimens was obtained from all individual participants included in the study.