Mouse liver assembloids model periportal architecture and biliary fibrosis

Modelling liver disease requires in vitro systems that replicate disease progression1,2. Current tissue-derived organoids fail to reproduce the complex cellular composition and tissue architecture observed in vivo3. Here, we describe a multicellular organoid system composed of adult hepatocytes, cholangiocytes and mesenchymal cells that recapitulates the architecture of the liver periportal region and, when manipulated, models aspects of cholestatic injury and biliary fibrosis. We first generate reproducible hepatocyte organoids with functional bile canaliculi network that retain morphological features of in vivo tissue. By combining these with cholangiocytes and portal fibroblasts, we generate assembloids that mimic the cellular interactions of the periportal region. Assembloids are functional, consistently draining bile from bile canaliculi into the bile duct. Strikingly, manipulating the relative number of portal mesenchymal cells is sufficient to induce a fibrotic-like state, independently of an immune compartment. By generating chimeric assembloids of mutant and wild-type cells, or after gene knockdown, we show proof-of-concept that our system is amenable to investigating gene function and cell-autonomous mechanisms. Taken together, we demonstrate that liver assembloids represent a suitable in vitro system to study bile canaliculi formation, bile drainage, and how different cell types contribute to cholestatic disease and biliary fibrosis, in an all-in-one model

RNF43/ZNRF3 loss predisposes to hepatocellular-carcinoma by impairing liver regeneration and altering the liver lipid metabolic ground-state.

RNF43/ZNRF3 negatively regulate WNT signalling. Both genes are mutated in several types of cancers, however, their contribution to liver disease is unknown. Here we describe that hepatocyte-specific loss of Rnf43/Znrf3 results in steatohepatitis and in increase in unsaturated lipids, in the absence of dietary fat supplementation. Upon injury, Rnf43/Znrf3 deletion results in defective hepatocyte regeneration and liver cancer, caused by an imbalance between differentiation/proliferation. Using hepatocyte-, hepatoblast- and ductal cell-derived organoids we demonstrate that the differentiation defects and lipid alterations are, in part, cell-autonomous. Interestingly, ZNRF3 mutant liver cancer patients present poorer prognosis, altered hepatic lipid metabolism and steatohepatitis/NASH signatures. Our results imply that RNF43/ZNRF3 predispose to liver cancer by controlling the proliferative/differentiation and lipid metabolic state of hepatocytes. Both mechanisms combined facilitate the progression towards malignancy. Our findings might aid on the management of those RNF43/ZNRF3 mutated individuals at risk of developing fatty liver and/or liver cancer

Advances in liver and pancreas organoids: how far we have come and where we go next

Over the past decade, advances in organoid culturing methods have enabled the growth of three-dimensional cellular cultures in vitro with increasing fidelity with respect to the cellular composition, architecture and function of in vivo organs. The increased accessibility and ability to manipulate organoids as an in vitro system have led to a shift in the landscape of experimental biology. Whether derived from stem cells or tissue-resident cells, organoids are now routinely used in studies of development, homeostasis, regeneration and disease modelling, including viral infection and cancer. These applications of organoids are highly relevant for gastrointestinal tissues, including the liver and pancreas. In this Review, we explore the current and emerging advances in liver and pancreas organoid technologies for both discovery and clinical translation research and provide an outlook on the challenges ahead

Perioperative complications of esophagectomy - prevention, diagnosis and management

Esophageal resection with reconstruction is complex surgical procedure with high rate of postoperative morbidity, with decreasing mortality rate during last decades, particularly in high-volume hospitals. Numerous preoperative, intraoperative and postoperative factors have contribute to incidence and type of complications. Intraoperative haemorrhage and tracheobronchial lesions could be avoid by good surgical judgement and operative technique. Pulmonary complications are often, with multifactorial etiology, and they are the main cause of postoperative mortality after esophagectomy. Dehiscence of esophageal anastomosis could be fatal, and only high index of suspicion and early diagnosis lead to successful treatment. In majority of such cases conservative measures are successful, however, conduit necrosis is indication for surgical reoperation. Vocal cord palsy due to intraoperative injury of recurrent laryngeal nerves is not rare and increases pulmonary complications rate. New onset of arrhythmia could be associate with other surgical complications. Postesophagectomy chylothorax is life-threatening complication due to rapid development of immunosuppression and septic complications, and early ligation of thoracic duct is often mandatory. Intrathoracic herniation of intrabdominal viscera is rare, and ischemic spinal cord lesions are very rare after esophagectomy. Majority of perioperative complications could be prevented or solved, decreasing mortality rate of esophagectomy.</jats:p

Possibility of Using Conventional Computed Tomography Features and Histogram Texture Analysis Parameters as Imaging Biomarkers for Preoperative Prediction of High-Risk Gastrointestinal Stromal Tumors of the Stomach

Background: The objective of this study is to determine the morphological computed tomography features of the tumor and texture analysis parameters, which may be a useful diagnostic tool for the preoperative prediction of high-risk gastrointestinal stromal tumors (HR GISTs). Methods: This is a prospective cohort study that was carried out in the period from 2019 to 2022. The study included 79 patients who underwent CT examination, texture analysis, surgical resection of a lesion that was suspicious for GIST as well as pathohistological and immunohistochemical analysis. Results: Textural analysis pointed out min norm (p = 0.032) as a histogram parameter that significantly differed between HR and LR GISTs, while min norm (p = 0.007), skewness (p = 0.035) and kurtosis (p = 0.003) showed significant differences between high-grade and low-grade tumors. Univariate regression analysis identified tumor diameter, margin appearance, growth pattern, lesion shape, structure, mucosal continuity, enlarged peri- and intra-tumoral feeding or draining vessel (EFDV) and max norm as significant predictive factors for HR GISTs. Interrupted mucosa (p &lt; 0.001) and presence of EFDV (p &lt; 0.001) were obtained by multivariate regression analysis as independent predictive factors of high-risk GISTs with an AUC of 0.878 (CI: 0.797&ndash;0.959), sensitivity of 94%, specificity of 77% and accuracy of 88%. Conclusion: This result shows that morphological CT features of GIST are of great importance in the prediction of non-invasive preoperative metastatic risk. The incorporation of texture analysis into basic imaging protocols may further improve the preoperative assessment of risk stratification

Organoids

Organoids have attracted increasing attention because they are simple tissue-engineered cell-based in vitro models that recapitulate many aspects of the complex structure and function of the corresponding in vivo tissue. They can be dissected and interrogated for fundamental mechanistic studies on development, regeneration, and repair in human tissues. Organoids can also be used in diagnostics, disease modeling, drug discovery, and personalized medicine. Organoids are derived from either pluripotent or tissue-resident stem (embryonic or adult) or progenitor or differentiated cells from healthy or diseased tissues, such as tumors. To date, numerous organoid engineering strategies that support organoid culture and growth, proliferation, differentiation and maturation have been reported. This Primer serves to highlight the rationale underlying the selection and development of these materials and methods to control the cellular/tissue niche; and therefore, structure and function of the engineered organoid. We also discuss key considerations for generating robust organoids, such as those related to cell isolation and seeding, matrix and soluble factor selection, physical cues and integration. The general standards for data quality, reproducibility and deposition within the organoid community is also outlined. Lastly, we conclude by elaborating on the limitations of organoids in different applications, and key priorities in organoid engineering for the coming years

RNF43/ZNRF3 loss predisposes to hepatocellular-carcinoma by impairing liver regeneration and altering the liver lipid metabolic ground-state

AbstractRNF43/ZNRF3 negatively regulate WNT signalling. Both genes are mutated in several types of cancers, however, their contribution to liver disease is unknown. Here we describe that hepatocyte-specific loss of Rnf43/Znrf3 results in steatohepatitis and in increase in unsaturated lipids, in the absence of dietary fat supplementation. Upon injury, Rnf43/Znrf3 deletion results in defective hepatocyte regeneration and liver cancer, caused by an imbalance between differentiation/proliferation. Using hepatocyte-, hepatoblast- and ductal cell-derived organoids we demonstrate that the differentiation defects and lipid alterations are, in part, cell-autonomous. Interestingly, ZNRF3 mutant liver cancer patients present poorer prognosis, altered hepatic lipid metabolism and steatohepatitis/NASH signatures. Our results imply that RNF43/ZNRF3 predispose to liver cancer by controlling the proliferative/differentiation and lipid metabolic state of hepatocytes. Both mechanisms combined facilitate the progression towards malignancy. Our findings might aid on the management of those RNF43/ZNRF3 mutated individuals at risk of developing fatty liver and/or liver cancer.</jats:p