ABSTRACT: A platform of patient-derived tumor xenografts (EOC-xenografts) to recapitulate the clinicopathology and genetic alterations of ovarian cancer
Project description:Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy. On the basis of its histopathology and molecular-genomic changes ovarian cancer has been divided into subtypes, each with distinct biology and outcome. The aim of this study was to develop a panel of patient-derived EOC-xenografts that recapitulate the molecular and biological heterogeneity of human ovarian cancer. Thirty-four EOC-xenografts were successfully established, either subcutaneously or intraperitoneally, in nude mice. The xenografts were histologically similar to the corresponding patient tumor and comprised all the major ovarian cancer subtypes. After orthotopic transplantation in the bursa of the mouse ovary, they disseminate into the organs of the peritoneal cavity and produce ascites, typical of ovarian cancer. Gene expression analysis and mutation status indicated a high degree of similarity with the original patient and discriminate different subsets of xenografts. They were very responsive, responsive and resistant to cisplatin, resembling the clinical situation in ovarian cancer. This panel of patient-derived EOC-xenografts that recapitulate the recently type I and type II classification serves to study the biology of ovarian cancer, identify tumor-specific molecular markers and develop novel treatment modalities. EOC-xenografts collected from subcutis, abdominal masses and ascitic fluid of mice engrafted with tumors at different passages (from 1 to 6) and from patient specimens, underwent one-color microarray-based gene expression profiling. To assess the amount of human- and mouse-derived cells in the xenograft tumors, total RNA was evaluated by species specific qPCR assays for beta actin. Only samples with a human RNA content > 75% were analyzed. Nine patient specimens and 62 xenograft samples (representing 29 EOC-xenograft models) underwent gene expression analysis with SurePrint G3 Human GE V2 8x60K microarrays.
Project description:Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy. On the basis of its histopathology and molecular-genomic changes ovarian cancer has been divided into subtypes, each with distinct biology and outcome. The aim of this study was to develop a panel of patient-derived EOC-xenografts that recapitulate the molecular and biological heterogeneity of human ovarian cancer. Thirty-four EOC-xenografts were successfully established, either subcutaneously or intraperitoneally, in nude mice. The xenografts were histologically similar to the corresponding patient tumor and comprised all the major ovarian cancer subtypes. After orthotopic transplantation in the bursa of the mouse ovary, they disseminate into the organs of the peritoneal cavity and produce ascites, typical of ovarian cancer. Gene expression analysis and mutation status indicated a high degree of similarity with the original patient and discriminate different subsets of xenografts. They were very responsive, responsive and resistant to cisplatin, resembling the clinical situation in ovarian cancer. This panel of patient-derived EOC-xenografts that recapitulate the recently type I and type II classification serves to study the biology of ovarian cancer, identify tumor-specific molecular markers and develop novel treatment modalities.
Project description:Epithelial ovarian cancer (EOC) is the most lethal gynecological tumor in developed countries and is characterized by high biological and molecular heterogeneity. High-grade serous ovarian carcinoma (HGSOC) is the most frequent and intractable form of the disease, mainly due to its rapid dissemination into the abdominal cavity, a process that is tightly linked to peritoneal ascites. Despite several studies provided insights into the genetic and epigenetic alterations relevant in EOC, the precise molecular alterations involved in tumor onset and progression remain largely unknown. Here we provide an experimental framework to perform a comprehensive investigation of molecular alterations relevant in HGSOC and ovarian cancer stem cells (OCSC) biology. We relied on a well characterized experimental set derived from human HGSOC-associated ascites and consisting of primary tumor cells, OCSC-enriched spheroids and serially propagated patient-derived xenografts, in order to define genetic and transcriptional signatures associated to specific HGSOC evolutionary trajectories. Such signatures exhibited prognostic value in a large cohort of HGSOC patients and allowed to define PI3K signaling as a novel vulnerability in OCSCs. Thus, our approach proved effective for the identification of druggable targets in HGSOC ascites, which is a major player in relapse and poor prognosis.
Project description:Prostate cancer translational research has been hampered by the lack of comprehensive and tractable models that represent the genomic landscape of clinical disease. Metastatic castrate-resistant prostate cancer (mCRPC) patient derived xenografts (PDXs) recapitulate the genetic and phenotypic diversity of the disease. We sought to establish a representative, preclinical platform of PDX-derived organoids that is experimentally facile for high throughput and mechanistic analysis.
Project description:Prostate cancer translational research has been hampered by the lack of comprehensive and tractable models that represent the genomic landscape of clinical disease. Metastatic castrate-resistant prostate cancer (mCRPC) patient derived xenografts (PDXs) recapitulate the genetic and phenotypic diversity of the disease. We sought to establish a representative, preclinical platform of PDX-derived organoids that is experimentally facile for high throughput and mechanistic analysis.
Project description:The patient-derived xenograft (PDX) model retains the heterogeneity of patient tumors, allowing a means to not only examine efficacy of a therapy across a population, but also study crucial aspects of cancer biology in response to treatment. Herein we describe the development and characterization of an ovarian-PDX model in order to study the development of chemoresistance. We demonstrate that PDX tumors are not simply composed of tumor-initiating cells, but recapitulate the original tumor’s heterogeneity, oncogene expression profiles, and clinical response to chemotherapy. Combined carboplatin/paclitaxel treatment of PDX tumors enriches the cancer stem cell populations, but persistent tumors are not entirely composed of these populations. RNA-Seq analysis of treated PDX tumors compared to untreated tumors demonstrates a consistently contrasting genetic profile after therapy, suggesting similar, but few, pathways are mediating chemoresistance. The pathways most significantly altered included Protein Kinase A signaling, GNRH signaling, and sphingosine-1-phosphate signaling. Pathways and genes identified by this methodology represent novel approaches to targeting the chemoresistant population in ovarian cancer 6 pairs of Patient-Derived Xenografts (PDX) were ananlyzed using RNA-seq for a total of 12 samples. Each pair consists of a treated and untreated PDX of ovarian cancer. Treated Ovarian cancer PDXs were treated with 4 weeks of a combination of carboplatin and taxol. RNA was isolated and converted to cDNA. RNA-seq was conductred on the Illumina HiSeq 2000 with 50 bp paired end sequencing
Project description:Epithelial ovarian cancer (EOC) is one of the most lethal gynecological cancers worldwide. EOC cells educate tumor-associated macrophages (TAMs) through CD44-mediated cholesterol depletion to generate an immunosuppressive tumor microenvironment (TME). In addition, tumor cells frequently activate Notch1 receptors on endothelial cells (ECs) to facilitate metastasis. However, little is known whether the endothelium would also influence the education of recruited monocytes. Here, we report that canonical Notch signaling through RBPJ in ECs is an important player in the education of TAMs and EOC progression. Deletion of Rbpj in the endothelium of adult mice reduced infiltration of monocyte-derived macrophages into the TME of EOC and prevented the acquisition of a typical TAM gene signature. This was associated with stronger cytotoxic activity of T cells and decreased tumor burden. Mechanistically, we identified CXCL2 as a novel Notch/RBPJ target gene. This angiocrine factor regulates the expression of CD44 on monocytes and subsequent cholesterol depletion of TAMs. Bioinformatic analysis of ovarian cancer patient data showed that increased CXCL2 expression is accompanied by higher expression of CD44 and TAM education. As such, EOC cells employ the tumor endothelium to secrete CXCL2 in order to facilitate an immunosuppressive microenvironment.
Project description:This project describes the establishment and validation of a murine orthotopic xenograft model using fresh human tumor samples that recapitulates the critical components of human pancreatic adenocarcinoma. The authors discuss the proven and theoretical advantages of the model as well as future translational implications. Background: Relevant preclinical models that recapitulate the key features of human pancreatic ductal adenocarcinoma (PDAC) are needed in order to provide biologically tractable models to probe disease progression and therapeutic responses and ultimately improve patient outcomes for this disease. Here, we describe the establishment and clinical, pathological, molecular and genetic validation of a murine, orthotopic xenograft model of PDAC. Methods: Human PDACs were resected and orthotopically implanted and propagated in immunocompromised mice. Patient survival was correlated with xenograft growth and metastatic rate in mice. Human and mouse tumor pathology were compared. Tumors were analyzed for genetic mutations, gene expression, receptor tyrosine kinase (RTK) activation, and cytokine expression. Results: Fifteen human PDACs were propagated orthotopically in mice. Xenografts developed peritoneal and liver metastases. Time to growth and metastatic efficiency in mice each correlated with patient survival. Tumor architecture, nuclear grade and stromal content were similar in patient and xenografted tumors. Propagated tumors closely exhibited the genetic and molecular features known to characterize pancreatic cancer (e.g. high rate of KRAS, p53, SMAD4 mutation and EGFR activation). The correlation coefficient of gene expression between patient tumors and xenografts propagated through multiple generations was 93 to 99%. Analysis of gene expression demonstrated distinct differences between xenografts from fresh patient tumors versus commercially available PDAC cell lines. Conclusions: Our orthotopic xenograft model derived from fresh human PDACs closely recapitulates the clinical, pathologic, genetic and molecular aspects of human disease. This model has resulted in the identification of rational therapeutic strategies to be tested in clinical trials and will permit additional therapeutic approaches and identification of biomarkers of response to therapy. 47 Samples in total were generated for normal pancreatic tissue in patients, pancreatic tumors in patients, pancreatic tumors propagated in a mouse xenograft model, and pancreatic cancer cell lines in vitro. Clustering analysis was performed to evaluate the differences between patient tumors, xenograft tumors, established cancer cell lines, and cell lines derived from xenografts.
Project description:Previously, we have identified the RUNX2 gene as hypomethylated and overexpressed in post-chemotherapy (CT) primary cultures derived from epithelial ovarian cancer (EOC) patients, when compared to primary cultures derived from matched primary (prior to CT) tumors. However, we found no differences in the RUNX2 methylation in primary EOC tumors and EOC omental metastases, suggesting that DNA methylation-based epigenetic mechanisms have no impact on RUNX2 expression in advanced (metastatic) stage of the disease. Moreover, RUNX2 displayed significantly higher expression not only in metastatic tissue, but also in high-grade primary tumors and even in low malignant potential tumors. Knockdown of the RUNX2 expression in EOC cells led to sharp decrease of cell proliferation and significantly inhibited EOC cell migration and invasion. Gene expression profiling and consecutive network and pathway analyses confirmed these findings, as various genes and pathways known previously to be implicated in ovarian tumorigenesis, including EOC tumor invasion and metastasis, were found to be downregulated upon RUNX2 suppression, while a number of pro-apoptotic genes and some EOC tumor suppressor genes were induced. Taken together, our data are indicative for a strong oncogenic potential of the RUNX2 gene in EOC progression and suggest that RUNX2 might be a novel EOC therapeutic target. Further studies are needed to more completely elucidate the functional implications of RUNX2 and other members of the RUNX gene family in ovarian tumorigenesis.
Project description:Availability of patient-derived sarcoma models that closely mimic human tumors remains a significant gap in cancer research as these models may not recapitulate the spectrum of sarcoma heterogeneity seen in patients. To characterize patient-derived models for functional studies, we made proteomic comparisons with originating sarcomas representative of the three intrinsic subtypes by mass spectrometry. Human protein profiling was found to be retained with high fidelity in patient-derived models. Patient derived xenografts locally invade and colonize stroma in mice which enables unambiguous molecular discrimination of human proteins in the tumor from mouse proteins in the microenvironment. We characterized protein profiling of patient sarcoma tumors and mouse stroma by species-specific quantitative proteomics. We found that protein expression in mouse stroma was affected by the primary human tumor. Our results showed that levels of stromal proteins derived from the tumor were lowered in PDXs and cell lines and part of human stromal proteins were replaced by corresponding mouse proteins in PDXs. This suggests that the effects of the microenvironment on drug response may not reflect those in the primary tumor. This cross-species proteomic analysis in PDXs could potentially improve preclinical evaluation of treatment modalities and enhance the ability to predict clinical trial responses.