Cell therapy in end-stage liver disease: replace and remodel.

Liver disease is prevalent worldwide. When it reaches the end stage, mortality rises to 50% or more. Although liver transplantation has emerged as the most efficient treatment for end-stage liver disease, its application has been limited by the scarcity of donor livers. The lack of acceptable donor organs implies that patients are at high risk while waiting for suitable livers. In this scenario, cell therapy has emerged as a promising treatment approach. Most of the time, transplanted cells can replace host hepatocytes and remodel the hepatic microenvironment. For instance, hepatocytes derived from donor livers or stem cells colonize and proliferate in the liver, can replace host hepatocytes, and restore liver function. Other cellular therapy candidates, such as macrophages and mesenchymal stem cells, can remodel the hepatic microenvironment, thereby repairing the damaged liver. In recent years, cell therapy has transitioned from animal research to early human studies. In this review, we will discuss cell therapy in end-stage liver disease treatment, especially focusing on various cell types utilized for cell transplantation, and elucidate the processes involved. Furthermore, we will also summarize the practical obstacles of cell therapy and offer potential solutions.

A mixed blessing for liver transplantation patients - Rapamycin.

BACKGROUND: Liver transplantation (LT) is an effective treatment option for end-stage liver disease. Mammalian target of rapamycin (mTOR) inhibitors, such as rapamycin, are widely used post LT. DATA SOURCES: In this review, we focused on the anti-cancer activities and metabolic side effects of rapamycin after LT. The literature available on PubMed for the period of January 1999-September 2022 was reviewed. The key words were rapamycin, sirolimus, liver transplantation, hepatocellular carcinoma, diabetes, and lipid metabolism disorder. RESULTS: Rapamycin has shown excellent effects and is safer than other immunosuppressive regimens. It has exhibited excellent anti-cancer activity and has the potential in preventing hepatocellular carcinoma (HCC) recurrence post LT. Rapamycin is closely related to two long-term complications after LT, diabetes and lipid metabolism disorders. CONCLUSIONS: Rapamycin prevents HCC recurrence post LT in some patients, but it also induces metabolic disorders. Reasonable use of rapamycin benefits the liver recipients.

Efficacy and safety of sirolimus early conversion protocol in liver transplant patients with hepatocellular carcinoma: A single-arm, multicenter, prospective study.

Mammalian target of rapamycin (mTOR) inhibitor as an attractive drug target with promising antitumor effects has been widely investigated. High quality clinical trial has been conducted in liver transplant (LT) recipients in Western countries. However, the pertinent studies in Eastern world are paucity. Therefore, we designed a clinical trial to test whether sirolimus can improve recurrence-free survival (RFS) in hepatocellular carcinoma (HCC) patients beyond the Milan criteria after LT. This is an open-labeled, single-arm, prospective, multicenter, and real-world study aiming to evaluate the clinical outcomes of early switch to sirolimus-based regimens in HCC patients after LT. Patients with a histologically proven HCC and beyond the Milan criteria will be enrolled. The initial immunosuppressant regimens are center-specific for the first 4-6 weeks. The following regimens integrated sirolimus into the regimens as a combination therapy with reduced calcineurin inhibitors based on the condition of patients and centers. The study is planned for 4 years in total with a 2-year enrollment period and a 2-year follow-up. We predict that sirolimus conversion regimen will provide survival benefits for patients particular in the key indicator RFS as well as better quality of life. If the trial is conducted successfully, we will have a continued monitoring over a longer follow-up time to estimate indicator of overall survival. We hope that the outcome will provide better evidence for clinical decision-making and revising treatment guidelines based on Chinese population data. Trial register: Trial registered at http://www.chictr.org.cn: ChiCTR2100042869.

Key factors and potential drug combinations of nonalcoholic steatohepatitis: Bioinformatic analysis and experimental validation-based study.

BACKGROUND: Nonalcoholic fatty liver disease and its advanced stage, nonalcoholic steatohepatitis (NASH), are the major cause of hepatocellular carcinoma (HCC) and other end-stage liver disease. However, the potential mechanism and therapeutic strategies have not been clarified. This study aimed to identify potential roles of miRNA/mRNA axis in the pathogenesis and drug combinations in the treatment of NASH. METHODS: Microarray GSE59045 and GSE48452 were downloaded from the Gene Expression Omnibus and analyzed using R. Then we obtained differentially expressed genes (DE-genes). DAVID database was used for Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment pathway analysis. Protein-protein interaction (PPI) networks were used for the identification of hub genes. We found upstream regulators of hub genes using miRTarBase. The expression and correlation of key miRNA and its targets were detected by qPCR. Drug Pair Seeker was employed to predict drug combinations against NASH. The expression of miRNA and hub genes in HCC was identified in the Cancer Genome Atlas database and Human Protein Atlas database. RESULTS: Ninety-four DE-genes were accessed. GO and KEGG analysis showed that these predicted genes were linked to lipid metabolism. Eleven genes were identified as hub genes in PPI networks, and they were highly expressed in cells with vigorous lipid metabolism. hsa-miR-335-5p was the upstream regulator of 9 genes in the 11 hub genes, and it was identified as a key miRNA. The hub genes were highly expressed in NASH models, while hsa-miR-335-5p was lowly expressed. The correlation of miRNA-mRNA was established by qPCR. Functional verification indicated that hsa-miR-335-5p had inhibitory effect on the development of NASH. Finally, drug combinations were predicted and the expression of miRNA and hub genes in HCC was identified. CONCLUSIONS: In the study, potential miRNA-mRNA pathways related to NASH were identified. Targeting these pathways may be novel strategies against NASH.

Hangzhou criteria as downstaging criteria in hepatocellular carcinoma before liver transplantation: A multicenter study from China.

BACKGROUND: The downstaging of hepatocellular carcinoma (HCC) has been confirmed to benefit liver transplantation (LT) patients whose tumors are beyond the transplantation criteria. Milan criteria (MC), a tumor size and number-based assessment, is currently used as the endpoint in these patients. However, many studies believe that tumor biological behavior should be added to the evaluation criteria for downstaging efficacy. Hence, this study aimed to explore the feasibility of Hangzhou criteria (HC), which introduced tumor grading and alpha-fetoprotein in addition to tumor size and number, as an endpoint of downstaging. METHODS: We performed a multicenter and retrospective study of 206 patients accepted locoregional therapy (LRT) as downstaging/bridge treatment prior to LT in three centers of China. RESULTS: Recipients were divided into four groups: failed downstaging to the HC (group A, n = 46), successful downstaging to the HC (group B, n = 30), remained within the HC all the time (group C, n = 113), and tumor progressed (group D, n = 17). The 3-year HCC recurrence probabilities of groups B and C were not significantly different (10.3% vs. 11.6%, P = 0.87). The HCC recurrent rate was significantly higher in group A (52.3%) compared with that in group B/C (P < 0.05). Seven patients (7/76, 9.2%) whose tumor exceeded the the HC were successfully downstaged to the MC, and 39.5% (30/76) to the the HC. In group B, 23 patients remained beyond the MC and their survivals were as well as those of patients within the MC. CONCLUSIONS: Compared to the MC, HC downstaging criteria can give more HCC patients access to LT and furthermore, the outcome of these patients is the same as those matching MC downstaging criteria. Hangzhou downstaging criteria therefore is applicable in clinical practice.

CC motif chemokine ligand 16 inhibits the progression of liver cirrhosis via inactivating hepatic stellate cells.

BACKGROUND: Liver cirrhosis results from many forms of chronic damage, characterized by accumulation of extracellular matrix. The present study aimed to explore a potential non-invasive biomarker and its mechanism in the progression of liver cirrhosis. METHODS: Gene Expression Omnibus (GEO) dataset (GSE15654, n = 216) was analyzed to screen genes associated with progression of liver cirrhosis. A total of 181 plasma samples, including healthy control (HC, n = 20), chronic hepatitis B (CHB, n = 77) and HBV-related liver cirrhosis (LC, n = 84), were enrolled for validation. In vitro and in vivo experiments were employed for the mechanistic investigation. RESULTS: GEO dataset analysis showed that relatively low mRNA-expression of CC motif chemokine ligand 16 (CCL16) was associated with elevated Child-Pugh score (P = 0.034) and worse prognosis (P = 0.025). Plasma CCL16 level decreased in a stepwise pattern, with a median concentration of 10.29, 6.57 and 4.47 ng/mL in the HC, CHB and LC groups, respectively (P<0.001). Low plasma CCL16 was significantly related to hepatic dysfunction both in the CHB and LC groups (P<0.05). Combination of CCL16 and ALT showed improved distinguishing capability for LC compared to either alone. In vitro, CCL16 expression was downregulated by lipopolysaccharide and hypoxia. Overexpression of CCL16 from human normal liver cell line (LO2) reduced the extracellular matrix associated proteins (Col1 and Col4) in human hepatic stellate cell line (LX-2). In vivo, the pathological feature of cirrhosis was alleviated by the hepatocyte-specific expression of CCL16. CONCLUSIONS: CCL16 could be a feasible plasma marker to predict the occurrence and progression of liver cirrhosis. CCL16 might impact liver cirrhosis through inactivating hepatic stellate cells.

Predictive value of tumor markers in patients with recurrent hepatocellular carcinoma in different vascular invasion pattern.

BACKGROUND: Four tumor markers for hepatocellular carcinoma (HCC), alpha-fetoprotein (AFP), glypican-3 (GPC3), vascular endothelial growth factor (VEGF) and des-gamma-carboxy prothrombin (DCP), are closely associated with tumor invasion and patient's survival. This study estimated the predictability of preoperative tumor marker levels along with pathological parameters on HCC recurrence after hepatectomy. METHODS: A total of 140 patients with HCC who underwent hepatectomy between January 2012 and August 2012 were enrolled. The demographics, clinical and follow-up data were collected and analyzed. The patients were divided into two groups: patients with macroscopic vascular invasion (MaVI+) and those without MaVI (MaVI-). The predictive value of tumor markers and clinical parameters were evaluated by univariate and multivariate analysis. RESULTS: In all patients, tumor size (>8 cm) and MaVI were closely related to HCC recurrence after hepatectomy. For MaVI+ patients, VEGF (>900 pg/mL) was a significant predictor for recurrence (RR=2.421; 95% CI: 1.272-4.606; P=0.007). The 1- and 2-year tumor-free survival rates for MaVI+ patients with VEGF ≤900 pg/mL versus for those with VEGF >900 pg/mL were 51.5% and 17.6% versus 19.0% and 4.8% (P<0.001). For MaVI- patients, DCP >445 mAu/mL and tumor size >8 cm were two independent risk factors for tumor recurrence (RR=2.307, 95% CI: 1.132-4.703, P=0.021; RR=3.150, 95% CI: 1.392-7.127, P=0.006; respectively). The 1- and 2-year tumor-free survival rates for the patients with DCP ≤445 mAu/mL and those with DCP >445 mAu/mL were 90.4% and 70.7% versus 73.2% and 50.5% respectively (P=0.048). The 1- and 2-year tumor-free survival rates for the patients with tumor size ≤8 cm and >8 cm were 83.2% and 62.1% versus 50.0% and 30.0%, respectively (P=0.003). CONCLUSIONS: The MaVI+ patients with VEGF ≤900 pg/mL had a relatively high tumor-free survival than those with VEGF >900 pg/mL. In the MaVI- patients, DCP >445 mAu/mL and tumor size >8 cm were predictive factors for postoperative recurrence.

ZIP4, a novel determinant of tumor invasion in hepatocellular carcinoma, contributes to tumor recurrence after liver transplantation.

BACKGROUND AND PURPOSE: Recently, evidence that Zinc transporter ZRT/IRT-like protein 4 (ZIP4) is involved in invasiveness and apoptosis has emerged in pancreatic cancer and prostate cancer. Our aim was to assess the role of ZIP4 in invasiveness, migration and apoptosis of hepatocellular carcinoma (HCC). The prognostic value of ZIP4 in HCC after liver transplantation was evaluated. METHODS: The role of ZIP4 in HCC was investigated by overexpressing ZIP4 in BEL7402 and HepG2 cells and inhibiting ZIP4 in HuH-7 and HepG2 cells, using overexpression and shRNA plasmids in vitro studies. Immunohistochemical analysis was used to evaluate ZIP4 expression in HCC tissues from 60 patients undergoing liver transplantation, 36 cirrhotic tissue samples, and 6 normal tissue samples. Prognostic significance was assessed using the Kaplan-Meier method and the log-rank test. RESULTS: Specific suppression of ZIP4 reduced cell migration and invasiveness, whereas ZIP4 overexpression caused increases in cell migration and invasiveness. Furthermore, overexpression of ZIP4 resulted in increased expression of pro-metastatic genes (MMP-2, MMP-9) and decreased expression of pro-apoptotic genes (caspase-3, caspase-9, Bax). In contrast, suppression of ZIP4 resulted in an opposite effect. ZIP4 was more highly expressed in tumor tissues than non-tumor tissues (P < 0.0001). ZIP4 expression was significantly associated with tumor recurrence (P = 0.002), tumor node metastasis stage (P = 0.044), Child-Turcotte-Pugh score (P = 0.042), and tumor size (P = 0.022). Univariate analysis showed that ZIP4 expression was significantly associated with overall survival (P = 0.020) and tumor-free survival (P = 0.049). Multivariate analysis revealed that ZIP4 was an independent predictor of overall survival (P = 0.037) after liver transplantation. CONCLUSIONS: ZIP4 could promote migration, invasiveness, and suppress apoptosis in hepatocellular carcinoma, and represent a novel predictor of poor prognosis and therapeutic target for patients with HCC who undergo liver transplantation.

Evaluation of hepatitis B viral replication and proteomic analysis of HepG2.2.15 cell line after knockdown of HBx.

BACKGROUND: Hepatitis B virus (HBV) is one of the major pathogens of human liver disease. Studies have shown that HBV X protein (HBx) plays an important role in promoting viral gene expression and replication. In this study we performed a global proteomic profiling to identify the downstream functional proteins of HBx, thereby detecting the mechanisms of action of HBx on virion replication. METHODS: HBx in the HepG2.2.15 cell line was knocked down by the transfection of small interfering RNA (siRNA). The replication level of HBV was evaluated by microparticle enzyme immunoassay analysis of HBsAg and HBeAg in the culture supernatant, and real-time quantitative PCR analysis of HBV DNA. Two-dimensional electrophoresis combined with MALDI-TOF/TOF was performed to analyze the changes in protein expression profile after treatment with HBx siRNA. RESULTS: Knockdown of HBx disturbed HBV replication in vitro. HBx target siRNA significantly inhibited the expression of HBsAg, HBeAg and the replication of HBV DNA. Twelve significantly changed proteins (7 upregulated and 5 downregulated) were successfully identified by MALDI-TOF/TOF using proteomics differential expression analysis after the knockdown of HBx. Among these identified proteins, HSP70 was validated by Western blotting. CONCLUSION: The results of the study indicated the positive effect of HBx on HBV replication, and a group of downstream target proteins of HBx may be responsible for this effect.

The impact of miR-34a on protein output in hepatocellular carcinoma HepG2 cells.

MicroRNAs are small non-coding RNA molecules that play essential roles in biological processes ranging from cell cycle to cell migration and invasion. Accumulating evidence suggests that miR-34a, as a key mediator of p53 tumor suppression, is aberrantly expressed in human cancers. In the present study, we aimed to explore the precise biological role of miR-34a and the global protein changes in HCC cell line HepG2 cells transiently transfected with miR-34a. Transfection of miR-34a into HepG2 cells caused suppression of cell proliferation, inhibition of cell migration and invasion. It also induced an accumulation of HepG2 cells in G1 phase. Among 116 protein spots with differential expression separated by 2-DE method, 34 proteins were successfully identified by MALDI-TOF/TOF analysis. Of these, 15 downregulated proteins may be downstream targets of miR-34a. Bioinformatics analysis produced a protein-protein interaction network, which revealed that the p53 signaling pathway and cell cycle pathway were two major hubs containing most of the proteins regulated by miR-34a. Cytoskeletal proteins such as LMNA, GFAP, MACF1, ALDH2, and LOC100129335 are potential targets of miR-34a. In conclusion, abrogation of miR-34a function could cause downstream molecules to switch on or off, leading to HCC development.