Prostate cancer patient‐derived organoids: detailed outcome from a prospective cohort of 81 clinical specimens

Abstract

Patient-derived organoids (PDOs) represent promising preclinical models in various tumor types. In the context of prostate cancer (PCa), however, their establishment has been hampered by poor success rates, which impedes their broad use for translational research applications. Along with the necessity to improve culture conditions, there is a need to identify factors influencing outcomes and to determine how to assess success versus failure in organoid generation. In the present study, we report our unbiased efforts to generate PDOs from a cohort of 81 PCa specimens with diverse pathological and clinical features. We comprehensively analyzed histological features of each enrolled sample (Gleason score, tumor content, proliferation index) and correlated them with organoid growth patterns. We identified improved culture conditions favoring the generation of PCa organoids, yet no specific intrinsic tumor feature was broadly associated with sustained organoid growth. In addition, we performed phenotypic and molecular characterization of tumor-organoid pairs using immunohistochemistry, immunofluorescence, fluorescence in situ hybridization, and targeted sequencing. Morphological and immunohistochemical profiles of whole organoids altogether provided a fast readout to identify the most promising ones. Notably, primary samples were associated with an initial take-rate of 83% (n = 60/72) in culture, with maintenance of cancer cells displaying common PCa alterations, such as PTEN loss and ERG overexpression. These cancer organoids were, however, progressively overgrown by organoids with a benign-like phenotype. Finally, out of nine metastasis samples, we generated a novel organoid model derived from a hormone-naïve lung metastasis, which displays alterations in the PI3K/Akt and Wnt/β-catenin pathways and responds to androgen deprivation. Taken together, our comprehensive study explores determinants of outcome and highlights the opportunities and challenges associated with the establishment of stable tumor organoid lines derived from PCa patients.

Live Cell Molecular Analysis of Primary Prostate Cancer Organoids Identifies Persistent Androgen Receptor Signaling

“…Successful establishment of PDCO cultures from organ-con ned primary PC requires an optimal amount of tumor content and overgrowth of normal epithelia and tumor-associated spindle cells has been previously reported in primary PC-derived ex vivo cultures diluting tumor biomarkers [4,23,24]. Therefore, it is important to assess cancer cell content in these cultures.…”

“…Recent advances in organotypic culture techniques have enabled ex vivo propagation of tumor-derived PDCOs that incorporate primary cell biology, 3D structural complexity, and tumor heterogeneity into in vitro model systems [2,4,23,33,16,[34][35][36][37]. The conventional approach to organoid analysis includes traditional tissue processing like FFPE and sectioning [4,23,24]. However, these techniques may hamper analysis due to sample loss, molecular cross-linking that results in irreversible changes of organic matrix and diminished epitope availability compromising biomarker detection [5][6][7].…”

Live cell molecular analysis of primary prostate cancer organoids identifies persistent androgen receptor signaling

“…Recent advances in organotypic culture techniques have enabled ex vivo propagation of tumor-derived PDCOs that incorporate primary cell biology, 3D structural complexity, and tumor heterogeneity into in vitro model systems [2,4,16,23,[33][34][35][36][37]. The conventional approach to organoid analysis includes traditional tissue processing like FFPE and sectioning [4,23,24]. However, these techniques may hamper analysis due to sample loss, molecular cross-linking that results in irreversible changes of organic matrix and diminished epitope availability compromising biomarker detection [5][6][7].…”

“…Successful establishment of PDCO cultures from organconfined primary PC requires an optimal amount of tumor content and overgrowth of normal epithelia and tumorassociated spindle cells has been previously reported in primary PC-derived ex vivo cultures diluting tumor biomarkers [4,23,24]. Therefore, it is important to assess cancer cell content in these cultures.…”

Application of Organoid Models in Prostate Cancer Research

“…Firstly, the overall success rate of PCa organoids is only 15-20% (17), limiting the extensive development of clinically diversified PCa models. A study produced statistics on organoids from 81 PCa specimens with diverse pathological and clinical features (53). The success rate of organoid development from metastatic prostatectomy reached 4/9 while that of organoid development from transurethral resection of the prostate was only 4/14.…”