Project description:Peritoneal metastases (PM) from colorectal cancer (CRC) are associated with poor survival. The extracellular matrix (ECM) plays a fundamental role in modulating the homing of CRC metastases to the peritoneum. The mechanisms underlying the interactions between metastatic cells and the ECM, however, remain poorly understood, and the number of in vitro models available for the study of the peritoneal metastatic process is limited. Here, we show that decellularized ECM of the peritoneal cavity allows the growth of organoids obtained from PM, favoring the development of three-dimensional (3D) nodules that maintain the characteristics of in vivo PM. Organoids preferentially grow on scaffolds obtained from neoplastic peritoneum, which are characterized by greater stiffness than normal scaffolds. A gene expression analysis of organoids grown on different substrates reflected faithfully the clinical and biological characteristics of the organoids. An impact of the ECM on the response to standard chemotherapy treatment for PM was also observed. The ex vivo 3D model, obtained by combining patient-derived decellularized ECM with organoids to mimic the metastatic niche, could be an innovative tool to develop new therapeutic strategies in a biologically relevant context to personalize treatments.
Project description:Models that recapitulate the complexity of human tumors are urgently needed to develop more effective cancer therapies. We report a bank of human patient-derived xenografts (PDXs) and matched organoid cultures from tumors that represent the greatest unmet need: endocrine-resistant, treatment-refractory and metastatic breast cancers. We leverage matched PDXs and PDX-derived organoids (PDxO) for drug screening that is feasible and cost-effective with in vivo validation. Moreover, we demonstrate the feasibility of using these models for precision oncology in real time with clinical care in a case of triple-negative breast cancer (TNBC) with early metastatic recurrence. Our results uncovered a Food and Drug Administration (FDA)-approved drug with high efficacy against the models. Treatment with this therapy resulted in a complete response for the individual and a progression-free survival (PFS) period more than three times longer than their previous therapies. This work provides valuable methods and resources for functional precision medicine and drug development for human breast cancer.
Project description:Metastasis formation is the major cause for cancer-related deaths and the underlying mechanisms remain poorly understood. In this study we describe spontaneous metastasis xenograft mouse models of human neuroblastoma used for unbiased identification of metastasis-related proteins by applying an infrared laser (IR) for sampling primary tumor and metastatic tissues, followed by mass spectrometric proteome analysis. IR aerosol samples were obtained from ovarian and liver metastases, which were indicated by bioluminescence imaging (BLI), and matched subcutaneous primary tumors. Corresponding histology proved the human origin of metastatic lesions. Ovarian metastases were commonly larger than liver metastases indicating differential outgrowth capacities. Among ~1,900 proteins identified at each of the three sites, 55 proteins were differentially regulated in ovarian metastases while 312 proteins were regulated in liver metastases. There was an overlap of 21 and 7 proteins up- and down-regulated at both metastatic sites, respectively, most of which were so far not related to metastasis such as LYPLA2, EIF4B, DPY30, LGALS7, PRPH, and NEFM. Moreover, we established in vitro sublines from primary tumor and metastases and demonstrate differences in cellular protrusions, migratory/invasive potential and glycosylation. Summarized, this work identified several novel putative drivers of metastasis formation that are tempting candidates for future functional studies.
Project description:Human organoids have been proposed to be powerful tools mimicking the physiopathological processes of the organs of origin. Recently, human pancreatic organoids (hPOs) have gained increasing attention due to potential theragnostic and regenerative medicine applications. However, the cellular components of hPOs have not been defined precisely. In this work, we finely characterized these structures, focusing first on morphology and identity-defining molecular features under long-term culture conditions. Next, we focused our attention on hPOs cell type composition using single-cell RNA sequencing founding a complex heterogeneity in ductal components, ranging from progenitor components to terminally differentiated ducts. Furthermore, an extensive comparison of human pancreatic organoids with previously reported transcriptomics signature of human and mouse pancreatic ductal populations, confirmed the functional pancreatic duct subpopulation heterogeneity. Finally, we showed that pancreatic organoid cells follow a precise developmental trajectory and utilize diverse signalling mechanisms, including EGF and SPP1, to facilitate cell-cell communication and maturation. Together our results offer an in-depth description of human pancreatic organoids providing a strong foundation for future in vitro diagnostic and translational studies of pancreatic health and disease.