Project description:To identify genes and pathways sepcific to tumorigenesis, we harvested tissues from two different liver tumor models as well as regenerating tissues. Genes significantly different in the two tumor models, but not in regenerating tissues, were used for further investigation
Project description:This study aimed to improve our understanding of the mechanisms of liver regeneration in sharks and to identify the microRNAs that participate in liver regeneration and other liver-related diseases. To this end, normal and regenerating liver tissues from C. plagiosum were harvested 0, 3, 6, 12 and 24 h after partial hepatectomy (PH) and were sequenced using the Illumina/Solexa platform. In total, 309 known microRNAs and 590 novel microRNAs were identified in C. plagiosum. There were 368 microRNAs differentially expressed between the normal and regenerating livers. Using target prediction and GO analysis, most of the differentially expressed microRNAs were assigned to functional categories that may be involved in regulating liver regeneration, such as cell proliferation, differentiation and apoptosis. Additionally, this study adds several novel microRNAs to the database, which will help identify microRNAs in other genetically related species and provides a starting point for future studies aimed at understanding the roles of microRNAs in liver regeneration and other liver diseases.
Project description:To identify the molecular targets of orosomucoid (Orm1) during liver regeneration, GeneChip analysis was performed at 48 h after partial hepatectomy (PH) in regenerating mouse liver treated with siControl or siOrm. A total of 180 differentially expressed genes in Orm1 konckdown mouse liver by comparing with siControl were identified with a fold change more than 2. Then, pathway analysis performed on the altered gene expression profiles using Ingenuity Pathways Analysis (IPA) program revealed that cell cycle, Toll-like receptor and TGF-beta receptor signaling pathways were under control of Orm1 in regenerating mouse livers. Three days post In vivo knockdown of Orm1 with its siRNA administered to mice using Invivofectamine 3.0 by a single injection, 40% PH was perfomred and gene expression prolifes of regenerating mouse livers at 48 h after PH was measued using Affymetrix GeneChip Mouse Genome 430A 2.0 Array.
Project description:To identify the molecular targets of orosomucoid (Orm1) during liver regeneration, GeneChip analysis was performed at 48 h after partial hepatectomy (PH) in regenerating mouse liver treated with siControl or siOrm. A total of 180 differentially expressed genes in Orm1 konckdown mouse liver by comparing with siControl were identified with a fold change more than 2. Then, pathway analysis performed on the altered gene expression profiles using Ingenuity Pathways Analysis (IPA) program revealed that cell cycle, Toll-like receptor and TGF-beta receptor signaling pathways were under control of Orm1 in regenerating mouse livers.
Project description:In this work, we applied single-cell transcriptome sequencing on primary human liver tissue samples to study cellular processes underlying human liver regeneration. In order to study regeneration-specific cellular processes we obtained primary healthy liver tissue samples and liver tissue samples from patients that underwent a preoperative medical procedure called portal vein embolization (PVE). This medical treatment is performed to enlarge part of the liver such that a diseased portion can be removed avoiding liver insufficiency and thus we used post-PVE-derived tissues as a model to study liver regeneration in humans. This paradigm enabled us to catalog cell states related to tissue structure in two important and physiologically relevant conditions: hypertrophy and atrophy. In addition, we overcame technical challenges and provided novel protocols and pipelines for generating high quality liver cell atlases from frozen specimens showing consistency in results between fresh and frozen tissue datasets. Moreover, we established tissue-scale iterative indirect immunofluorescence imaging to enable high-dimensional spatial analysis of perivascular microenvironments and uncover cellular and histological alterations to regenerating liver lobules.
Project description:The adult liver has exceptional ability to regenerate, but how it sustains normal metabolic activities during regeneration remains unclear. Here, we use partial hepatectomy (PHx) in tandem with single-cell transcriptomics to track cellular transitions and heterogeneities of ~22,000 liver cells through the initiation, progression, and termination phases of mouse liver regeneration. Our results reveal that following PHx, a subset of hepatocytes transiently reactivates an early-postnatal-like gene expression program to proliferate, while a distinct population of metabolically hyperactive cells appears to compensate for any temporary deficits in liver function. Importantly, through combined analysis of gene regulatory networks and cell- cell interaction maps, we find that regenerating hepatocytes redeploy key developmental gene regulons, which are guided by extensive ligand–receptor mediated signaling events between hepatocytes and non-parenchymal cells. Altogether, our study offers a detailed blueprint of the intercellular crosstalk and cellular reprogramming that balances the metabolic and proliferation requirements of a regenerating liver.
Project description:The therapeutic regimens of adjuvant and neoadjuvant chemotherapy for colorectal cancer (CRC) remain largely relied on clinical experience, and thus preclinical models are needed to guide individualized medicine. The investigators are going to establish 3D bioprinted CRC models and organoids from surgically resected tumor tissues of CRC patients with or without liver metastases. In vitro 3D models and organoids will be treated with the same chemotherapy drugs with the corresponding patients from whom the models are derived. The sensitivity of chemotherapy drugs will be tested in these two types of in vitro models, and the actual response to chemotherapy in patients will be evaluated. The predictive ability of 3D models for chemotherapy sensitivity in CRC patients will be compared with that of the organoids. This observational study will validate the potential value of 3D bioprinted tumor models in predicting the response to chemotherapy in CRC.