Project description:Circulating Tumor Cells (CTCs) are shed from primary tumors into the bloodstream, mediating the hematogenous spread of cancer to distant organs. Using a pancreatic cancer mouse model, we applied a microfluidic device to isolate CTCs independently of tumor epitopes, subjecting these to single cell RNA-sequencing. This study was conducted to determine the heterogeneity of pancreatic CTCs and to compare these CTCs to matched primary tumors, cell line controls (NB508 cancer cell line and MEF non-cancer cell line), primary tumor single cells, and normal leukocytes/WBCs. We profiled RNA from 75 single cells circulating in mouse blood enriched for circulating tumor cells from 5 mice, 12 single cells from a mouse embryonic fibroblast cell line, 16 single cells from the nb508 mouse pancreatic cancer cell line, 12 single mouse white blood cells, 18 single GFP lineage-traced circulating tumor cells from two mice, 20 single GFP lineage-traced cancer cells from the primary pancreatic tumor of a mouse, and 34 dilutions to 10 or 100 picograms of total RNA from mouse primary pancreatic tumors from 4 mice.
Project description:Aging-related degeneration of pancreatic islet cells contributes to impaired glucose tolerance and diabetes. Endocrine cells age heterogeneously, complicating the effort to unravel the molecular drives underlying endocrine aging. To overcome these obstacles, we undertook single-cell RNA sequencing of pancreatic islet cells obtained from young and aged non-diabetic cynomolgus monkeys. Despite sex differences and increased single-cell level transcriptional variations, aged β-cells showed increased unfolded protein response (UPR) along with the accumulation of protein aggregates. We observed transcriptomic dysregulation of UPR components linked to canonical ATF6 and IRE1 signaling, comprising adaptive UPR during pancreatic aging. Notably, we found age-related β-cell-specific upregulation of HSP90B1, an ER-located chaperone, impeded high glucose-induced insulin secretion. Our work decodes aging-associated transcriptomic changes that underlie pancreatic islet functional decay at the single-cell resolution and indicates that targeting UPR components may prevent loss of proteostasis, suggesting an avenue for therapies to delay β-cell aging and prevent aging-related diabetes.
Project description:Differential CpG methylation profiling for KMT2D and HNF4A genomic region in pancreatic cancer cells was performed using Illumina MiSeq.
Project description:Human pancreatic islets, including insulin secreting beta-cells are a major focus of transplantation strategies aimed at identifying new therapeutic approaches to counteract hyperglycemia in patients with diabetes. Identifying the transcriptomic signature of human islet cells provides insights into regulatory pathways that can be harnessed for planning therapeutic strategies. In this context, single-cell RNA-sequencing (scRNA-seq) has been used mostly in vitro. However, in experimental human islet transplantation models the small amount of tissue is principally used for immunostaining and poses a challenge in performing ‘omics’ studies that provide unbiased information. To circumvent this limitation, we report the use of single nucleus RNA-sequencing (snRNA-seq) on frozen/archived human islet grafts, to define the transcriptomic signature of islet cells preserved after in vivo studies. Interrogating nuclear RNA, we were able to successfully identify all islet endocrine cells, obtain adequate coverage of genes and define molecular pathways that are important for studying human islet cell biology (e.g. cell cycle, apoptosis, insulin secretion). Intersecting our nuclear transcriptomic output with publicly available single-cell RNA-seq datasets, revealed ~90% overlap of the detected genes. In conclusion, we propose that snRNA-seq represents a reliable strategy to probe transcriptomic profiles of fresh or archived transplanted human islets.
Project description:In this study, 30 pancreatic tissues were retrieved, including 20 samples of pancreatic ductal cell carcinoma and 10 of adjacent healthy tissues. All pancreatic samples were obtained from the First Hospital of Lanzhou University from January 2016 to December 2020.
Project description:To better understand the underlying mechanism of beta-cell regeneration in adult zebrafish, we performed single-cell transcriptomic profiling of the pancreatic tissue (using 10X Genomics) at various stages post beta-cell ablation.