Patient-derived ovarian cancer organoids capture the genomic profiles of primary tumours applicable for drug sensitivity and resistance testing

Abstract

The use of primary patient-derived organoids for drug sensitivity and resistance testing could play an important role in precision cancer medicine. We developed expandable ovarian cancer organoids in < 3 weeks; these organoids captured the characteristics of histological cancer subtypes and replicated the mutational landscape of the primary tumours. Seven pairs of organoids (3 high-grade serous, 1 clear cell, 3 endometrioid) and original tumours shared 59.5% (36.1-73.1%) of the variants identified. Copy number variations were also similar among organoids and primary tumours. The organoid that harboured the BRCA1 pathogenic variant (p.L63*) showed a higher sensitivity to PARP inhibitor, olaparib, as well as to platinum drugs compared to the other organoids, whereas an organoid derived from clear cell ovarian cancer was resistant to conventional drugs for ovarian cancer, namely platinum drugs, paclitaxel, and olaparib. The overall success rate of primary organoid culture, including those of various histological subtypes, was 80% (28/35). Our data show that patient-derived organoids are suitable physiological ex vivo cancer models that can be used to screen effective personalised ovarian cancer drugs. Patient-derived tumour organoids have become important preclinical model systems in both cancer research and clinical settings 1. In contrast to patient-derived xenograft (PDX) mouse models that need a large amount of surgical specimen and 4-8 months for development 2 , organoids can be cultured from patient materials and can be expanded with high efficiency in a relatively short period (typically < 1 month). Organoids from mouse intestine, as well as from various other mouse and human tissues, including the colon, stomach, liver, lung, prostate, and pancreas, have been established 3,4. Patient-derived tumour organoids have also been generated from the colon, pancreas, prostate, breast, gastric, lung, oesophageal, bladder, ovarian, kidney, and liver tumour tissues 1. Organoids maintain the key genetic and phenotypic features of primary tumours, thereby, enabling their use in a broad range of applications, such drug development and identification of the best therapeutic regimen for each patient. Ovarian cancer is a devastating disease, with 295,000 new patients and 185,000 deaths each year, worldwide 5. The relative 5-year survival rate is 47% and has not apparently increased in the last 40 years. Debulking surgery with platinum-combination chemotherapy is usually administered to patients, irrespective of the histological

Organoid and Spheroid Tumor Models: Techniques and Applications

“…Most importantly, the drugs identified were validated in vivo with matched PDTX models, providing proof-of-concept that the patient-derived organoids can be utilized for complete genomic analysis together with high-throughput drug screening of a comprehensive up-to-date library [ 98 ]. Similarly, several other studies have shown that tumor organoids and spheroids can be utilized for anti-cancer drug screening [ 18 , 19 , 21 , 54 , 56 , 92 , 94 , 96 , 99 , 100 , 101 , 102 , 103 , 104 , 105 ].…”

Patient-derived organoids and high grade serous ovarian cancer: from disease modeling to personalized medicine

“…Compared to the classical 2D cancer cell lines, organoids are more difficult to operate and more expensive to maintain. However, they represent more reliably the pathological features of the tumor, as PDOs maintain genetic stability and tumor heterogeneity [6,[8][9][10][67][68][69][70][71][72][73][74], which instead are lost during the long-term selection required to establish 2D tumor cell lines. In comparison with patient-derived xenografts (PDXs) or genetically engineered animal models, PDOs are less time consuming, less expensive and more appropriate for high-throughput drug screening.…”

“…In comparison with patient-derived xenografts (PDXs) or genetically engineered animal models, PDOs are less time consuming, less expensive and more appropriate for high-throughput drug screening. Furthermore, PDOs are usually obtained with higher success rate than PDXs and can also be formed from non-transformed cell cultures or preinvasive cancer models [6,[8][9][10][67][68][69][70][71][72][73][74]. Lastly, with respect to spheroids, which are clusters of proliferating cells that assemble in 3D sphere-like structures floating in the culture medium [75], PDOs offer a better representation of the architecture of the tumor, as they assemble onto a reconstituted matrix that resembles the basal lamina of epithelia and recapitulate the cellular heterogeneity of the tumor mass.…”

“…Lastly, with respect to spheroids, which are clusters of proliferating cells that assemble in 3D sphere-like structures floating in the culture medium [75], PDOs offer a better representation of the architecture of the tumor, as they assemble onto a reconstituted matrix that resembles the basal lamina of epithelia and recapitulate the cellular heterogeneity of the tumor mass. Nevertheless, one limitation of PDOs is currently represented by the lack of reliable protocols capable to faithfully reproduce the tumor microenvironment, which comprises the stroma, immune cells and blood vessels [6,[8][9][10][67][68][69][70][71][72][73][74]. However, the recent development of organoids cocultured with tumor microenvironment components holds promise for the possibility to evaluate complex features of tumors in the near future [76,77].…”

“…Several protocols to obtain PDO cultures from OC have been reported in the past three years [6,[8][9][10][67][68][69][70][71][72][73][74]. The main experimental conditions and key findings of these studies are summarized in Table 1.…”