Novel anti-inflammatory peptide alleviates liver ischemia-reperfusion injury.

Ischemia-reperfusion injury (IRI) remains inevitable in liver surgeries, macrophages play a critical role in the development of IRI, but little is known about the macrophages regulate pathogenesis of IRI. Based on target-guided screening, we identified a small 3 kDa peptide (SjDX5-271) from various schistosome egg-derived peptides that induced M2 macrophage polarization. SjDX5-271 treatment protected the mice against liver IRI through promoting M2 macrophage polarization, the protective effect was abrogated when the macrophages were depleted. Transcriptomic sequencing showed that the TLR signaling pathway was significantly inhibited in macrophages derived from the SjDX5-271 treatment group. We further identified that SjDX5-271 promotes M2 macrophage polarization by inhibiting the TLR4/MyD88/NF-κB signaling pathway and further alleviates hepatic inflammation in liver IRI. Collectively, SjDX5-271 exhibits promising therapeutic effects in IRI and represents a novel therapeutic approach for IRI, even in immune-related diseases. This study revealed the development of a new biologic from the parasite and enhanced our understanding of host-parasite interplay, providing a blueprint for future therapies for immune-related diseases.

Myeloid Trem2 ameliorates the progression of metabolic dysfunction-associated steatotic liver disease by regulating macrophage pyroptosis and inflammation resolution.

BACKGROUND: The prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD) is increasing year by year and has become one of the leading causes of end-stage liver disease worldwide. Triggering Receptor Expressed on Myeloid Cells 2 (Trem2) has been confirmed to play an essential role in the progression of MASLD, but its specific mechanism still needs to be clarified. This study aims to explore the role and mechanism of Trem2 in MASLD. METHODS: Human liver tissues were obtained from patients with MASLD and controls. Myeloid-specific knockout mice (Trem2mKO) and myeloid-specific overexpression mice (Trem2TdT) were fed a high-fat diet, either AMLN or CDAHFD, to establish the MASLD model. Relevant signaling molecules were assessed through lipidomics and RNA-seq analyses after that. RESULTS: Trem2 is upregulated in human MASLD/MASH-associated macrophages and is associated with hepatic steatosis and inflammation progression. Hepatic steatosis and inflammatory responses are exacerbated with the knockout of myeloid Trem2 in MASLD mice, while mice overexpressing Trem2 exhibit the opposite phenomenon. Mechanistically, Trem2mKO can aggravate macrophage pyroptosis through the PI3K/AKT signaling pathway and amplify the resulting inflammatory response. At the same time, Trem2 promotes the inflammation resolution phenotype transformation of macrophages through TGFß1, thereby promoting tissue repair. CONCLUSIONS: Myeloid Trem2 ameliorates the progression of Metabolic dysfunction-associated steatotic liver disease by regulating macrophage pyroptosis and inflammation resolution. We believe targeting myeloid Trem2 could represent a potential avenue for treating MASLD.

Blockade of Hepatocyte PCSK9 Ameliorates Hepatic Ischemia-Reperfusion Injury by Promoting Pink1-Parkin-Mediated Mitophagy.

BACKGROUND & AIMS: Hepatic ischemia-reperfusion injury is a significant complication of partial hepatic resection and liver transplantation, impacting the prognosis of patients undergoing liver surgery. The protein proprotein convertase subtilisin/kexin type 9 (PCSK9) is primarily synthesized by hepatocytes and has been implicated in myocardial ischemic diseases. However, the role of PCSK9 in hepatic ischemia-reperfusion injury remains unclear. This study aims to investigate the role and mechanism of PCSK9 in hepatic ischemia-reperfusion injury. METHODS: We first examined the expression of PCSK9 in mouse warm ischemia-reperfusion models and AML12 cells subjected to hypoxia/reoxygenation. Subsequently, we explored the impact of PCSK9 on liver ischemia-reperfusion injury by assessing mitochondrial damage and the resulting inflammatory response. RESULTS: Our findings reveal that PCSK9 is up-regulated in response to ischemia-reperfusion injury and exacerbates hepatic ischemia-reperfusion injury. Blocking PCSK9 can alleviate hepatocyte mitochondrial damage and the consequent inflammatory response mediated by ischemia-reperfusion. Mechanistically, this protective effect is dependent on mitophagy. CONCLUSIONS: Inhibiting PCSK9 in hepatocytes attenuates the inflammatory responses triggered by reactive oxygen species and mitochondrial DNA by promoting PINK1-Parkin-mediated mitophagy. This, in turn, ameliorates hepatic ischemia-reperfusion injury.

Endothelial DGKG promotes tumor angiogenesis and immune evasion in hepatocellular carcinoma.

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is among the most prevalent and lethal cancers worldwide. The tumor microenvironment (TME) contributes to the poor response of patients with HCC to current therapies, while tumor vascular endothelial cells (ECs) are fundamental TME components that significantly contribute to tumor progression. However, the specific functions and mechanisms of tumor vascular ECs in HCC remain unclear. METHODS: We screened and validated diacylglycerol kinase gamma (DGKG) hyper-expression specifically in HCC tumor vascular ECs. Single-cell RNA-sequencing, cytometry by time-of-flight, and in vitro and in vivo studies were performed to investigate the functions of endothelial DGKG. Multiplexed immunohistochemistry staining and flow cytometry were used to evaluate changes in the TME. RESULTS: Functionally, endothelial DGKG promotes tumor angiogenesis and immunosuppressive regulatory T-cell differentiation in HCC. Of significance, we found that HIF-1α activates DGKG transcription by directly binding to its promoter region under hypoxia. Upregulated DGKG promotes HCC progression by recruiting ubiquitin specific peptidase 16 to facilitate ZEB2 deubiquitination, which increases TGF-ß1 secretion, thus inducing tumor angiogenesis and regulatory T-cell differentiation. Importantly, targeting endothelial DGKG potentiated the efficiency of dual blockade of PD-1 and VEGFR-2. CONCLUSION: Hypoxia-induced EC-specific DGKG hyper-expression promotes tumor angiogenesis and immune evasion via the ZEB2/TGF-ß1 axis, suggesting EC-specific DGKG as a potential therapeutic target for HCC. IMPACT AND IMPLICATIONS: Here, we reported that hypoxia-induced endothelial cell-specific DGKG hyper-expression promotes angiogenesis and immune evasion in HCC by recruiting USP16 for K48-linked deubiquitination and inducing the subsequent stabilization of ZEB2, leading to increased TGF-ß1 secretion. Most importantly, endothelial DGKG inhibition greatly improved the efficacy of the dual combination of anti-VEGFR2 and anti-PD-1 treatment in a mouse HCC model, significantly inhibiting the malignant progression of HCC and improving survival. This preclinical study supports the targeting of endothelial DGKG as a potential strategy for precision HCC treatment.

Correction: miR-146a Ameliorates Liver Ischemia/Reperfusion Injury by Suppressing IRAK1 and TRAF6.

[This corrects the article DOI: 10.1371/journal.pone.0101530.].

Myeloid Trem2 Dynamically Regulates the Induction and Resolution of Hepatic Ischemia-Reperfusion Injury Inflammation.

Trem2, a transmembrane protein that is simultaneously expressed in both bone marrow-derived and embryonic-derived liver-resident macrophages, plays a complex role in liver inflammation. The unique role of myeloid Trem2 in hepatic ischemia-reperfusion (IR) injury is not precisely understood. Our study showed that in the early stage of inflammation induction after IR, Deletion of myeloid Trem2 inhibited the induction of iNOS, MCP-1, and CXCL1/2, alleviated the accumulation of neutrophils and mitochondrial damage, and simultaneously decreased ROS formation. However, when inflammatory monocyte-macrophages gradually evolved into CD11bhiLy6Clow pro-resolution macrophages through a phenotypic switch, the story of Trem2 took a turn. Myeloid Trem2 in pro-resolution macrophages promotes phagocytosis of IR-accumulated apoptotic cells by controlling Rac1-related actin polymerization, thereby actively promoting the resolution of inflammation. This effect may be exercised to regulate the Cox2/PGE2 axis by Trem2, alone or synergistically with MerTK/Arg1. Importantly, when myeloid Trem2 was over-expressed, the phenotypic transition of monocytes from a pro-inflammatory to a resolution type was accelerated, whereas knockdown of myeloid Trem2 resulted in delayed upregulation of CX3CR1. Collectively, our findings suggest that myeloid Trem2 is involved in the cascade of IR inflammation in a two-sided capacity, with complex and heterogeneous roles at different stages, not only contributing to our understanding of sterile inflammatory immunity but also to better explore the regulatory strategies and intrinsic requirements of targeting Trem2 in the event of sterile liver injury.

Thymidine kinase 1 drives hepatocellular carcinoma in enzyme-dependent and -independent manners.

Metabolic reprogramming plays a crucial role in the development of hepatocellular carcinoma (HCC). However, the key drivers of metabolic reprogramming underlying HCC progression remain unclear. Using a large-scale transcriptomic database and survival correlation screening, we identify thymidine kinase 1 (TK1) as a key driver. The progression of HCC is robustly mitigated by TK1 knockdown and significantly aggravated by its overexpression. Furthermore, TK1 promotes the oncogenic phenotypes of HCC not only through its enzymatic activity and production of deoxythymidine monophosphate (dTMP) but also by promoting glycolysis via binding with protein arginine methyltransferase 1 (PRMT1). Mechanistically, TK1 directly binds PRMT1 and stabilizes it by interrupting its interactions with tripartite-motif-containing 48 (TRIM48), which inhibits its ubiquitination-mediated degradation. Subsequently, we validate the therapeutic capacity of hepatic TK1 knockdown in a chemically induced HCC mouse model. Therefore, targeting both the enzyme-dependent and -independent activity of TK1 may be therapeutically promising for HCC treatment.

Hepatocyte SGK1 activated by hepatic ischemia-reperfusion promotes the recurrence of liver metastasis via IL-6/STAT3.

BACKGROUND: Liver metastasis is the leading cause of death in patients with colorectal cancer (CRC). Surgical resection of the liver metastases increases the incidence of long-term survival in patients with colorectal liver metastasis (CRLM). However, many patients experience CRLM recurrence after the initial liver resection. As an unavoidable pathophysiological process in liver surgery, liver ischemia-reperfusion (IR) injury increases the risk of tumor recurrence and metastasis. METHODS: Colorectal liver metastasis (CRLM) mouse models and mouse liver partial warm ischemia models were constructed. The levels of lipid peroxidation were detected in cells or tissues. Western Blot, qPCR, elisa, immunofluorescence, immunohistochemistry, scanning electron microscope, flow cytometry analysis were conducted to evaluate the changes of multiple signaling pathways during CRLM recurrence under liver ischemia-reperfusion (IR) background, including SGK1/IL-6/STAT3, neutrophil extracellular traps (NETs) formation, polymorphonuclear myeloid-derived suppressor cell (PMN-MDSC) infiltration. RESULTS: Hepatocyte serum/glucocorticoid regulated kinase 1 (SGK1) was activated in response to hepatic ischemia-reperfusion injury to pass hepatocyte STAT3 phosphorylation and serum amyloid A (SAA) hyperactivation signals in CRLM-IR mice, such regulation is dependent on SGK-activated IL-6 autocrine. Administration of the SGK1 inhibitor GSK-650394 further reduced ERK-related neutrophil extracellular traps (NETs) formation and polymorphonucler myeloid-derived suppressor cells (PMN-MDSC) infiltration compared with targeting hepatocyte SGK1 alone, thereby alleviating CRLM in the context of IR. CONCLUSIONS: Our study demonstrates that hepatocyte and immune cell SGK1 synergistically promote postoperative CRLM recurrence in response to hepatic IR stress, and identifies SGK1 as a translational target that may improve postoperative CRLM recurrence.

PRDM1/BLIMP1 induces cancer immune evasion by modulating the USP22-SPI1-PD-L1 axis in hepatocellular carcinoma cells.

Programmed death receptor-1 (PD-1) blockade have achieved some efficacy but only in a fraction of patients with hepatocellular carcinoma (HCC). Programmed cell death 1 ligand 1 (PD-L1) binds to its receptor PD1 on T cells to dampen antigen-tumor immune responses. However, the mechanisms underlying PD-L1 regulation are not fully elucidated. Herein, we identify that tumoral Prdm1 overexpression inhibits cell growth in immune-deficient mouse models. Further, tumoral Prdm1 overexpression upregulates PD-L1 levels, dampening anti-tumor immunity in vivo, and neutralizes the anti-tumor efficacy of Prdm1 overexpression in immune-competent mouse models. Mechanistically, PRDM1 enhances USP22 transcription, thus reducing SPI1 protein degradation through deubiquitination, which enhances PD-L1 transcription. Functionally, PD-1 mAb treatment reinforces the efficacy of Prdm1-overexpressing HCC immune-competent mouse models. Collectively, we demonstrate that the PRDM1-USP22-SPI1 axis regulates PD-L1 levels, resulting in infiltrated CD8+ T cell exhaustion. Furthermore, PRDM1 overexpression combined with PD-(L)1 mAb treatment provides a therapeutic strategy for HCC treatment.

Efficacy and safety of camrelizumab plus apatinib during the perioperative period in resectable hepatocellular carcinoma: a single-arm, open label, phase II clinical trial.

OBJECTIVE: This study aimed to assess the efficacy and safety of camrelizumab plus apatinib in patients with resectable hepatocellular carcinoma (HCC) as neoadjuvant therapy. METHODS: Initially, 20 patients with HCC were screened and 18 patients with resectable HCC were enrolled in this open-label, single-arm, phase II clinical trial. Patients received three cycles of neoadjuvant therapy including three doses of camrelizumab concurrent with apatinib for 21 days followed by surgery. Four to 8 weeks after surgery, patients received eight cycles of adjuvant therapy with camrelizumab in combination with apatinib. Major pathological reactions (MPR), complete pathological reactions (pCR), objective response rate (ORR), relapse-free survival (RFS), and adverse events (AE) were assessed. In addition, cancer tissue and plasma samples were collected before and after treatment, and genetic differences between responding and non-responding lesions were compared by tumor immune microenvironment (TIME) analysis, circulating tumor DNA (ctDNA) analysis and proteomics analysis. RESULTS: In 18 patients with HCC who completed neoadjuvant therapy, 3 (16.7%) and 6 (33.3%) patients with HCC reached ORR based on Response Evaluation Criteria in Solid Tumors (RECIST) V.1.1 and modified RECIST criteria, respectively. Of the 17 patients with HCC who received surgical resection, 3 (17.6%) patients with HCC reported MPR and 1 (5.9%) patient with HCC achieved pCR. The 1-year RFS rate of the enrolled patients was 53.85% (95% CI: 24.77% to 75.99%). Grade 3/4 AEs were reported in 3 (16.7%) of the 18 patients, with the most common AEs being rash (11.1%), hypertension (5.6%), drug-induced liver damage (5.6%), and neutropenia (5.6%) in the preoperative phase. The 289 NanoString panel RNA sequencing showed that TIME cell infiltration especially dendritic cells (DCs) infiltration was better in responding tumors than in non-responding tumors. Our results of ctDNA revealed a higher positive rate (100%) among patients with HCC with stage IIb-IIIa disease. When comparing patients with pCR/MPR and non-MPR, we observed more mutations in patients who achieved pCR/MPR at baseline (6 mutations vs 2.5 mutations, p=0.025). Patients who were ctDNA positive after adjuvant therapy presented a trend of shorter RFS than those who were ctDNA negative. Proteomic analysis suggested that abnormal glucose metabolism in patients with multifocal HCC might be related to different sensitivity of treatment in different lesions. CONCLUSION: Perioperative camrelizumab plus apatinib displays a promising efficacy and manageable toxicity in patients with resectable HCC. DCs infiltration might be a predictive marker of response to camrelizumab and apatinib as well as patients' recurrence. ctDNA as a compose biomarker can predict pathological response and relapse. Abnormal glucose metabolism in patients with multifocal HCC may be related to different sensitivity of treatment in different lesions. TRIAL REGISTRATION NUMBER: NCT04297202.

Aging deteriorated liver Ischemia and reperfusion injury by suppressing Tribble's proteins 1 mediated macrophage polarization.

Aggravated liver injury has been reported in aged ischemia/reperfusion-stressed livers; however, the mechanism of aged macrophage inflammatory regulation is not well understood. Here, we found that the adaptor protein TRIB1 plays a critical role in the differentiation of macrophages and the inflammatory response in the liver after ischemia/reperfusion injury. In the present study, we determined that aging promoted macrophage-mediated liver injury and that inflammation was mainly responsible for lower M2 polarization in liver transplantation-exposed humans post I/R. Young and aged mice were subjected to hepatic I/R modeling and showed that aging aggravated liver injury and suppressed macrophage TRIB1 protein expression and anti-inflammatory function in I/R-stressed livers. Restoration of TRIB1 is mediated by lentiviral infection-induced macrophage anti-inflammatory M2 polarization and alleviated hepatic I/R injury. Moreover, TRIB1 overexpression in macrophages facilitates M2 polarization and anti-inflammation by activating MEK1-ERK1/2 signaling under IL-4 stimulation. Taken together, our results demonstrated that aging promoted hepatic I/R injury by suppressing TRIB1-mediated MEK1-induced macrophage M2 polarization and anti-inflammatory function.

Targeting SYK of monocyte-derived macrophages regulates liver fibrosis via crosstalking with Erk/Hif1α and remodeling liver inflammatory environment.

Liver fibrosis is a danger signal indicating a huge risk of liver cancer occurrence, but there is still no effective clinical means to regulate the progress of liver fibrosis. Although a variety of drugs targeting SYK have been developed for tumors and autoimmune diseases, the mechanism and specific efficacy of SYK's role in liver fibrosis are not yet clear. Our studies based on chronic CCL4, bile duct ligation, and subacute TAA mouse models show that SYK in monocyte-derived macrophages (MoMFs) is fully dependent on phosphorylation of Erk to up-regulate the expression of Hif1α, thereby forming the crosstalk with SYK to drive liver fibrosis progress. We have evaluated the ability of the small molecule SYK inhibitor GS9973 in a variety of models. Contrary to previous impressions, high-frequency administration of GS9973 will aggravate CCL4-induced liver fibrosis, which is especially unsuitable for patients with cholestasis whose clinical features are bile duct obstruction. In addition, we found that inhibition of MoMFs SYK impairs the expression of CXCL1, on one hand, it reduces the recruitment of CD11bhiLy6Chi inflammatory cells, and on the other hand, it promotes the phenotype cross-dress process of pro-resolution MoMFs, thereby remodeling the chronic inflammatory environment of the fibrotic liver. Our further findings indicate that on the basis of the administration of CCR2/CCR5 dual inhibitor Cenicriviroc, further inhibiting MoMFs SYK may give patients with fibrosis additional benefits.

Inhibiting ATP6V0D2 Aggravates Liver Ischemia-Reperfusion Injury by Promoting NLRP3 Activation via Impairing Autophagic Flux Independent of Notch1/Hes1.

At present, liver ischemia-reperfusion (IR) injury is still a great challenge for clinical liver partial resection and liver transplantation. The innate immunity regulated by liver macrophages orchestrates the cascade of IR inflammation and acts as a bridge. As a specific macrophage subunit of vacuolar ATPase, ATP6V0D2 (V-ATPase D2 subunit) has been shown to promote the formation of autophagolysosome in vitro. Our research fills a gap which has existed in the study of inflammatory stress about the V-ATPase subunit ATP6V0D2 in liver macrophages. We first found that the expression of specific ATP6V0D2 in liver macrophages was upregulated with the induction of inflammatory cascade after liver IR surgery, and knockdown of ATP6V0D2 resulted in increased secretion of proinflammatory factors and chemokines, which enhanced activation of NLRP3 and aggravation of liver injury. Further studies found that the exacerbated activation of NLRP3 was related to the autophagic flux regulated by ATP6V0D2. Knocking down ATP6V0D2 impaired the formation of autophagolysosome and aggravated liver IR injury through nonspecific V-ATPase activation independent of V-ATPase-Notchl-Hesl signal axis. In general, we illustrated that the expression of ATP6V0D2 in liver macrophages was upregulated after liver IR, and by gradually promoting the formation of autophagolysosomes to increase autophagy flux to limit the activation of liver inflammation, this regulation is independent of the Notch1-Hes1 signal axis.

HIF-1α-induced expression of m6A reader YTHDF1 drives hypoxia-induced autophagy and malignancy of hepatocellular carcinoma by promoting ATG2A and ATG14 translation.

N6-methyladenosine (m6A), and its reader protein YTHDF1, play a pivotal role in human tumorigenesis by affecting nearly every stage of RNA metabolism. Autophagy activation is one of the ways by which cancer cells survive hypoxia. However, the possible involvement of m6A modification of mRNA in hypoxia-induced autophagy was unexplored in human hepatocellular carcinoma (HCC). In this study, specific variations in YTHDF1 expression were detected in YTHDF1-overexpressing, -knockout, and -knockdown HCC cells, HCC organoids, and HCC patient-derived xenograft (PDX) murine models. YTHDF1 expression and hypoxia-induced autophagy were significantly correlated in vitro; significant overexpression of YTHDF1 in HCC tissues was associated with poor prognosis. Multivariate cox regression analysis identified YTHDF1 expression as an independent prognostic factor in patients with HCC. Multiple HCC models confirmed that YTHDF1 deficiency inhibited HCC autophagy, growth, and metastasis. Luciferase reporter assays and chromatin immunoprecipitation demonstrated that HIF-1α regulated YTHDF1 transcription by directly binding to its promoter region under hypoxia. The results of methylated RNA immunoprecipitation sequencing, proteomics, and polysome profiling indicated that YTHDF1 contributed to the translation of autophagy-related genes ATG2A and ATG14 by binding to m6A-modified ATG2A and ATG14 mRNA, thus facilitating autophagy and autophagy-related malignancy of HCC. Taken together, HIF-1α-induced YTHDF1 expression was associated with hypoxia-induced autophagy and autophagy-related HCC progression via promoting translation of autophagy-related genes ATG2A and ATG14 in a m6A-dependent manner. Our findings suggest that YTHDF1 is a potential prognostic biomarker and therapeutic target for patients with HCC.

Eva1a inhibits NLRP3 activation to reduce liver ischemia-reperfusion injury via inducing autophagy in kupffer cells.

Ischemia-reperfusion(IR) injury is one of the main complications of liver transplantation and partial hepatectomy. Innate immunity mediated by kupffer cells plays an important role in it. In this study, we focused on evaluating the intrinsic relationship between the autophagy induction of kupffer cells and the activation of NLRP3 inflammasomes caused by liver ischemia-reperfusion. Pre-depletion of kupffer cells can aggravate inflammation and tissue damage within 24 h after IR.Enhancing the autophagy of kupffer cells can inhibit the activation of NLRP3 caused by IR, and inhibiting autophagy can induce the secretion of IL1ß dependent on NLRP3 activation.Eva1a is up-regulated by the inflammatory cascade activated by IR.Knockdown of Eva1a in vivo on the one hand will aggravate IR inflammation, increase the production of TNF-α, IL-1ß and inhibit the secretion of IL-10.On the other hand, it will aggravate the liver histological damage. Knockout of Eva1a induces ASC activation and cleavage of caspase1 and IL1ß in an NLRP3-dependent manner, which is closely related to the function of blocking Eva1a to promote autophagosome formation.We further found that knockdown of ATG16L1 will reverse the more formation of autophagosomes induced by overexpression of Eva1a, whereas knockdown of ATG16L1 did not further reduce the formation of autophagosomes inhibited by siEva1a. We also found that the addition of siATG7, siATG5 and siATG12 would reverse the IR autophagy of liver induced by overexpression of Eva1a, but inhibition of the Beclin1-Vps34 pathway did not significantly reverse the effect of overexpression of Eva1a.These prove that Eva1a and ATG16L1 may work together in the liver IR model to actively induce the formation of autophagosomes and be independent from the beclin1-vps34-induced autophagy pathway to limit the excessive activation of IR inflammation. Our study provides brand new insights into the mechanism of liver macrophages in the progression of inflammation in the context of liver ischemia-reperfusion injury.

Hypomethylation-mediated activation of cancer/testis antigen KK-LC-1 facilitates hepatocellular carcinoma progression through activating the Notch1/Hes1 signalling.

OBJECTIVES: Kita-Kyushu lung cancer antigen-1 (KK-LC-1) is a cancer/testis antigen reactivated in several human malignancies. So far, the major focus of studies on KK-LC-1 has been on its potential as diagnostic biomarker and immunotherapy target. However, its biological functions and molecular mechanisms in cancer progression remain unknown. MATERIALS AND METHODS: Expression of KK-LC-1 in HCC was analysed using RT-qPCR, Western blot and immunohistochemistry. The roles of KK-LC-1 on HCC progression were examined by loss-of-function and gain-of-function approaches. Pathway inhibitor DAPT was employed to confirm the regulatory effect of KK-LC-1 on the downstream Notch signalling. The interaction of KK-LC-1 with presenilin-1 was determined by co-immunoprecipitation. The association of CpG island methylation status with KK-LC-1 reactivation was evaluated by methylation-specific PCR, bisulphite sequencing PCR and 5-Aza-dC treatment. RESULTS: We identified that HCC tissues exhibited increased levels of KK-LC-1. High KK-LC-1 level independently predicted poor survival outcome. KK-LC-1 promoted cell growth, migration, invasion and epithelial-mesenchymal transition in vitro and in vivo. KK-LC-1 modulated the Notch1/Hes1 pathway to exacerbate HCC progression through physically interacting with presenilin-1. Upregulation of KK-LC-1 in HCC was attributed to hypomethylated CpG islands. CONCLUSIONS: This study identified that hypomethylation-induced KK-LC-1 overexpression played an important role in HCC progression and independently predicted poor survival. We defined the KK-LC-1/presenilin-1/Notch1/Hes1 as a novel signalling pathway that was involved in the growth and metastasis of HCC.

Precoagulation with microwave ablation for hepatic parenchymal transection during liver partial resection.

PURPOSE: To evaluate the feasibility of precoagulation with microwave ablation (MWA) for hepatic parenchymal transection during liver partial resection. METHODS: A total of 66 eligible patients were enrolled in this double-blind, randomized, controlled study. Patients were randomized to receive either the traditional clamp-crushing method (Control group) or the MWA precoagulation method (MWA group) for hepatic parenchymal transection during liver partial resection. The operative time, hepatic portal occlusion time, intraoperative blood loss and transfusion, postoperative complications and recovery outcomes were compared. RESULTS: Compared to the Control group, the MWA group had significantly less intraoperative blood loss. Fewer red blood cell transfusions were observed in the MWA group but without statistical significance. The MWA group showed significantly higher serum alanine aminotransferase and aspartate aminotransferase levels at day 1 postoperatively, but no differences between the MWA and Control groups were found at days 3 and 7. There were no significant differences in terms of operative time, hepatic portal occlusion time, postoperative total bilirubin levels, human albumin solution consumption or length of hospital stay. Postoperative complications such as impaired renal function, pyrexia, admission to ICU, abscess, biliary leakage, intrahepatic and distant tumor recurrence and in-hospital mortality were comparable between the two groups. CONCLUSION: Precoagulation with MWA reduced intraoperative blood loss with similar postoperative complications, providing a safe, effective, novel alternative for hepatic parenchymal transection during liver partial resection. Additional results from larger series are recommended to confirm these findings.

circLARP4 induces cellular senescence through regulating miR-761/RUNX3/p53/p21 signaling in hepatocellular carcinoma.

Circular RNAs (circRNAs), a novel class of non-coding RNAs, have emerged as indispensable modulators in human malignancies. Aberrant cellular senescence is a phenotype observed in various cancers. The association of circRNAs with cellular senescence in tumors is yet to determined. Here, we investigated the role of circLARP4 in cellular senescence and cell proliferation in hepatocellular carcinoma (HCC). Downregulated circLARP4 level was observed in HCC tissues and cell lines. Low expression level of circLARP4 independently predicted poor survival outcome. Gain-of-function and loss-of-function assays demonstrated that circLARP4 suppressed HCC cell proliferation, mediated cell cycle arrest and induced senescence in vitro. Levels of p53 and p21, 2 key regulatory molecules in cellular senescence, were increased in circLARP4-overexpressed HCC cells and decreased in circLARP4-silenced HCC cells. In vivo experiments further confirmed the tumor-suppressing activity of circLARP4. Further mechanistic studies showed that circLARP4 dampened HCC progression by sponging miR-761, thereby promoting the expression level of RUNX3 and activating the downstream p53/p21 signaling. Our study revealed the role of circLARP4/miR-761/RUNX3/p53/p21 signaling in HCC progression, providing a potential survival predictor and therapeutic candidate for HCC.

5-Hydroxytryptamine Receptor 1D Aggravates Hepatocellular Carcinoma Progression Through FoxO6 in AKT-Dependent and Independent Manners.

Serotonin and its receptors have been shown to play critical regulatory roles in cancer biology. Nevertheless, the contributions of 5-hydroxytryptamine 1D (5-HT1D), an indispensable member of the serotonergic system, to hepatocellular carcinoma (HCC) remain unknown. The present study demonstrated that the 5-HT1D expression level was significantly up-regulated in HCC tissues and cell lines. The 5-HT1D expression level was closely correlated with unfavorable clinicopathological characteristics. Survival analyses show that elevated 5-HT1D expression level predicts poor overall survival and high recurrence probability in HCC patients. Functional studies revealed that 5-HT1D significantly promoted HCC proliferation, epithelial-mesenchymal transition, and metastasis in vitro and in vivo. Mechanistically, 5-HT1D could stabilize PIK3R1 by inhibiting its ubiquitin-mediated degradation. The interaction between 5-HT1D and phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) enhanced the expression of FoxO6 through the PI3K/Akt signaling pathway; FoxO6 could also be directly transcriptionally activated by 5-HT1D in an Akt-independent manner. MicroRNA-599 was found to be an upstream suppressive modulator of 5-HT1D. Additionally, 5-HT1D could attenuate tryptophan hydroxylase 1 expression through the PI3K/Akt/cut-like homeobox 1 axis in HCC. Conclusion: Herein, we uncovered the potent oncogenic effect of 5-HT1D on HCC by interacting with PIK3R1 to activate the PI3K/Akt/FoxO6 pathway, and provided a potential therapeutic target for HCC.

Immune Responsive Release of Tacrolimus to Overcome Organ Transplant Rejection.

Transplant rejection is the key problem in organ transplantation and, in clinic, immunosuppressive agents such as tacrolimus are directly administered to the recipients after surgery for T-cell inhibition. However, direct administration of tacrolimus may bring severe side effects to the recipients. Herein, by rational design of two hydrogelators NapPhePheGluTyrOH (1) and Nap d-Phe dPheGluTyrOH (2), a facile method of immune responsive release of tacrolimus is developed from their hydrogels to overcome organ transplantation rejection. Upon incubation with protein tyrosine kinase, which is activated in T cells after organ transplantation, the tacrolimus-encapsulating Gel 1 or Gel 2 is disassembled to release tacrolimus. Cell experiments show that both Gel 1 and Gel 2 have better inhibition effect on the activated T cells than free drug tacrolimus. Liver transplantation experiments indicate that, after 7 days of treatment of same dose tacrolimus, the recipient rats in the Gel 2 group show significantly extended median survival time of 22 days while the recipients treated with conventional tacrolimus medication have a median survival time of 13 days. It is expected herein that this "smart" facile method of immune responsive release of tacrolimus can be applied to overcome organ transplantation rejection in clinic in the near future.