Project description:The generation of pancreatic organoids from human pluripotent stem cells represents a major breakthrough for regenerative medicine and the modeling of diseases such as diabetes. However, current approaches remain inefficient due to lengthy multi-step differentiation protocols and limited functional maturity in the organoids. In this study, we overcome these challenges using multi-phase optimization screens to achieve rapid generation of functionally mature pancreatic organoids from a stable endocrine progenitor culture. We conducted stepwise culture condition screens that enabled the stable culture of multiple pancreatic progenitor cell states, including the unprecedented stable propagation of NEUROD1-expressing endocrine progenitor-like cells (EpSCs). Further transcriptomic profiling of EpSC confirmed similarity of that to previously reported endocrine progenitor populations. Using EpSCs, we significantly reduced the number of steps and timing required to generate pancreatic organoids, enabling rapid testing of conditions for organoid maturation. Utilizing this optimized protocol, we further tested conditions to promote pancreatic organoid maturation. We identified that exosome-delivered WNT5B, in combination with RSPO1 (exoW/R), could strongly induce non-canonical WNT/JNK signaling, promoting pancreatic organoid maturation. This combinatorial exosome treatment enhances epithelial organization, reduces immature cell states, and significantly improves glucose responsiveness and insulin secretion. Collectively, our work establishes a robust pancreatic differentiation platform that integrates long-term progenitor expansion with optimized organoid maturation. This system provides a reproducible experimental framework for studying pancreatic development, investigating disease mechanisms, and facilitating future translational applications involving pancreatic organoids.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a heterogeneous cancer in which differences in survival rates might be related to a variety in gene expression profiles. Although the molecular biology of PDAC begins to be revealed, genes or pathways that specifically drive tumour progression or metastasis are not well understood. Therefore, we performed microarray analyses on whole-tumour samples of 2 human PDAC subpopulations with similar clinicopathological features, but extremely distinct survival rates after potentially curative surgery, i.e., good outcome (OS and DFSM-bM-^@M-^I>M-bM-^@M-^I50M-bM-^@M-^Imonths) versus bad outcome (OSM-bM-^@M-^I<M-bM-^@M-^I19M-bM-^@M-^Imonths and DFSM-bM-^@M-^I<M-bM-^@M-^I7M-bM-^@M-^Imonths). Additionally, liver- and peritoneal metastases were analysed and compared to primary cancer tissue. The integrin and ephrin receptor families were upregulated in all PDAC samples, irrespective of outcome, supporting an important role of the interaction between pancreatic cancer cells and the surrounding desmoplastic reaction in tumorigenesis and cancer progression. Moreover, some components, such as ITGB1 and EPHA2, were upregulated in PDAC samples with a poor outcome, Additionally, overexpression of the non-canonical Wnt/M-NM-2-catenin pathway and EMT genes in PDAC samples with bad versus good outcome suggests their contribution to the invasiveness of pancreatic cancer, with M-NM-2-catenin being also highly upregulated in metastatic tissue. Thus, we conclude that components of the integrin and ephrin pathways and EMT-related genes might serve as molecular markers in pancreatic cancer as their expression seems to be related with prognosis. Microarray analysis was performed on 'Good' and 'Bad' patient samples (samples with similar pathological characteristics were chosen based on the definition of the 2 diverse survival outcome groups and the required RIN values above 7.1), on surrounding non-tumoural pancreatic control samples, liver metastasis (LM) and peritoneal metastasis (PM). Comparisons between good vs. control, bad vs. control, good vs. bad, and primary pancreatic cancer versus metastasis were performed.
Project description:<p>BRCA1 mutations are a hallmark of hereditary ovarian cancer, strongly linked to deficiencies in homologous recombination (HR) DNA repair and impaired DNA replication fork protection. However, its roles in cancer progression beyond maintaining genomic integrity remain poorly understood. Through metabolomics approaches, we found BRCA1-deficiency strikingly increased choline metabolism. Loss of BRCA1 promotes choline uptake through upregulating choline transporter-like protein 4 (CTL4). BRCA1 directly binds and recruits EZH2-mediated H3K27Me3 deposition to CTL4 promoter. CTL4 was therefore overexpressed in ovarian cancer tissues with BRCA1 mutations. Furthermore, BRCA1-deficiency significantly promotes ovarian cancer invasion, while inhibition of CTL4 reverses the high metastatic potential of BRCA1-deficient ovarian cancer cells, suggesting the functionality and specificity of CTL4 as a therapeutic target. Additionally, we discovered that phosphocholine, the choline metabolite increased by CTL4 overexpression, interacted with and stabilized the epithelial-to-mesenchymal transition inducer FAM3C in BRCA1-deficient ovarian cancer cells. Importantly, we identified a potent CTL4 inhibitor, DT-13, which significantly reduces choline metabolism and effectively suppresses metastasis in BRCA1-deficient ovarian cancers. Therefore, our study uncovers a mechanism underlying metastasis in BRCA1-deficient cancers and identifies CTL4 as a therapeutic target for metastatic ovarian cancer patients with BRCA1 mutations.</p>
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a heterogeneous cancer in which differences in survival rates might be related to a variety in gene expression profiles. Although the molecular biology of PDAC begins to be revealed, genes or pathways that specifically drive tumour progression or metastasis are not well understood. Therefore, we performed microarray analyses on whole-tumour samples of 2 human PDAC subpopulations with similar clinicopathological features, but extremely distinct survival rates after potentially curative surgery, i.e., good outcome (OS and DFS > 50 months) versus bad outcome (OS < 19 months and DFS < 7 months). Additionally, liver- and peritoneal metastases were analysed and compared to primary cancer tissue. The integrin and ephrin receptor families were upregulated in all PDAC samples, irrespective of outcome, supporting an important role of the interaction between pancreatic cancer cells and the surrounding desmoplastic reaction in tumorigenesis and cancer progression. Moreover, some components, such as ITGB1 and EPHA2, were upregulated in PDAC samples with a poor outcome, Additionally, overexpression of the non-canonical Wnt/β-catenin pathway and EMT genes in PDAC samples with bad versus good outcome suggests their contribution to the invasiveness of pancreatic cancer, with β-catenin being also highly upregulated in metastatic tissue. Thus, we conclude that components of the integrin and ephrin pathways and EMT-related genes might serve as molecular markers in pancreatic cancer as their expression seems to be related with prognosis.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Molecular Markers for Predicting Treatment Outcome in Patients with Rectal Cancer: A Comprehensive Analysis from the German Rectal Cancer Trials