Longer warm ischemia can accelerate tumor growth through the induction of HIF-1α and the IL-6-JAK-STAT3 signaling pathway in a rat hepatocellular carcinoma model

SYK promotes the formation of neutrophil extracellular traps by inducing PKM2 nuclear translocation and promoting STAT3 phosphorylation to exacerbate hepatic ischemia-reperfusion injury and tumor recurrence

BACKGROUND

At present, hepatic ischemia-reperfusion injury (IRI) is an important complication of partial hepatectomy and liver transplantation, and it is an important cause of poor prognosis. Spleen tyrosine kinase(SYK) plays an important role in a variety of signaling pathways in the liver, but its role in hepatic IRI is still unclear. This study aims to investigate the role and mechanism of SYK in hepatic IRI and tumor recurrence.

METHODS

We first observed the activation of SYK in the liver of mice in response to hepatic IRI. Subsequently, Pharmacological inhibitions of SYK were used to evaluated the effect of SYK on neutrophil recruitment and NETosis, and further explored the effect of SYK on IRI and tumor recurrence.

RESULTS

Our study shows that SYK is activated in response to hepatic IRI and aggravates liver injury. On the one hand, neutrophils SYK during the early stage of liver reperfusion increases neutrophil extracellular traps (NETs) production by promoting Pyruvate kinase M2(PKM2) nuclear translocation leading to upregulation of phosphorylated STAT3, thereby exacerbating liver inflammation and tumor recurrence. On the other hand, macrophages SYK can promote the recruitment of neutrophils and increase the activation of NLRP3 inflammasome and IL1β, which further promotes the formation of NETs.

CONCLUSIONS

Our study demonstrates that neutrophil and macrophage SYK synergistically promote hepatic IRI and tumor recurrence, and SYK may be a potential target to improve postoperative hepatic IRI and tumor recurrence.

Innovations in Liver Preservation Techniques for Transplants from Donors after Circulatory Death: A Special Focus on Transplant Oncology

Liver transplantation is the preferred treatment for end-stage liver disease. Emerging evidence suggests a potential role for liver transplantation in treating liver tumors such as colorectal liver metastases and cholangiocarcinoma. However, due to a limited donor pool, the use of marginal grafts from donation after circulatory death (DCD) donors is increasing to meet demand. Machine perfusion is crucial in this context for improving graft acceptance rates and reducing ischemia-reperfusion injury. Few studies have evaluated the role of machine perfusion in the context of transplant oncology. Perfusion machines can be utilized in situ (normothermic regional perfusion-NRP) or ex situ (hypothermic and normothermic machine perfusion), either in combination or as a complement to conventional in situ cold flush and static cold storage. The objective of this analysis is to provide an up-to-date overview of perfusion machines and their function in donation after circulatory death with particular attention to their current and likely potential effects on transplant oncology. A literature review comparing standard cold storage to machine perfusion methods showed that, so far, there is no evidence that these devices can reduce the tumor recurrence rate. However, some evidence suggests that these innovative perfusion techniques can improve graft function, reduce ischemia-reperfusion injury, and, based on this mechanism, may lead to future improvements in cancer recurrence.

Downregulation of malic enzyme 3 facilitates progression of gastric carcinoma via regulating intracellular oxidative stress and hypoxia-inducible factor-1α stabilization

BACKGROUND

Gastric cancer (GC) is one of the most malignant cancers worldwide. Metabolism disorder is a critical characteristic of malignant tumors related to tumor progression and metastasis. However, the expression and molecular mechanism of malic enzyme 3 (ME3) in GC are rarely reported. In this study, we aim to investigate the molecular mechanism of ME3 in the development of GC and to explore its potential value as a prognostic and therapeutic target in GC.

METHOD

ME3 mRNA and protein expression were evaluated in patients with GC using RT-qPCR, WB, and immunohistochemistry, as well as their correlation with clinicopathological indicators. The effect of ME3 on proliferation and metastasis was evaluated using Cell Counting Kit-8 (CCK-8), 5-ethynyl-20-deoxyuridine (EdU) assay, transwell assay, wound healing assay, and subcutaneous injection or tail vein injection of tumor cells in mice model. The effects of ME3 knockdown on the level of metabolites and hypoxia-inducible factor-1α (HIF-1α) protein were determined in GC cells. Oxidative phosphorylation was measured to evaluate adenosine triphosphate (ATP) production.

RESULTS

ME3 was downregulated in human GC tissues (P < 0.001). The decreased ME3 mRNA expression was associated with younger age (P = 0.02), pathological staging (P = 0.049), and lymph node metastasis (P = 0.001), while low ME3 expression was associated with tumor size (P = 0.048), tumor invasion depth (P < 0.001), lymph node metastasis (P = 0.018), TNM staging (P < 0.001), and poor prognosis (OS, P = 0.0206; PFS P = 0.0453). ME3 knockdown promoted GC cell malignancy phenotypes. Moreover, α-ketoglutarate (α-KG) and NADPH/NADP+ ratios were reduced while malate was increased in the ME3 knockdown group under normoxia. When cells were incubated under hypoxia, the NADPH/NADP+ ratio and α-KG decreased while intracellular reactive oxygen species (ROS) increased significantly. The ME3 knockdown group exhibited an increase in ATP production and while ME3 overexpression group exhibited oppositely. We discovered that ME3 and HIF-1α expression were negatively correlated in GC cells and tissues, and proposed the hypothesis: downregulation of ME3 promotes GC progression via regulating intracellular oxidative stress and HIF-1α.

CONCLUSION

We provide evidence that ME3 downregulation is associated with poor prognosis in GC patients and propose a hypothesis for the ME3 regulatory mechanism in GC progression. The present study is of great scientific significance and clinical value for exploring the prognostic and therapeutic targets of GC, evaluating and improving the clinical efficacy of patients, reducing recurrence and metastasis, and improving the prognosis and quality of life of patients.

Hepatoprotection of a Standardized Extract of Cultured Lentinula edodes Mycelia against Liver Injury Induced by Ischemia-Reperfusion and Partial Hepatectomy

A standardized extract of cultured Lentinula edodes mycelia (ECLM, AHCC®) has been shown to have beneficial effects on organ metabolism. ECLM has been indicated to have liver protective properties by suppressing inflammatory responses. The pathogenesis of hepatic ischemia-reperfusion injury is thought to involve the induction of inflammatory mediators. However, whether ECLM affects inflammatory mediators caused by warm hepatic ischemia-reperfusion injury and partial hepatectomy (HIRI+PH) has not been clarified. In this study, we evaluated the protective effects of ECLM against liver damage caused by HIRI+PH. Rats were fed a normal diet (HIRI+PH) or a normal diet with 2% ECLM (HIRI+PH and ECLM) for ten days, then the liver and duodenal ligament were clamped and subjected to 15 min of hepatic ischemia. After 70% hepatectomy, the inflow occlusion was released, and liver and blood samples were collected at 3, 6, and 24 h. The effect of ECLM on mortality induced by 30 min of ischemia and hepatectomy was evaluated. The results showed that ECLM attenuated pathological liver damage, including apoptosis, in the rats treated with HIRI+PH, and decreased serum aminotransferase activity; ECLM decreased mRNA levels of the inflammation-related genes inducible nitric oxide synthase and C-X-C motif chemokine ligand 1, and increased mRNA levels of interleukin 10, an anti-inflammatory cytokine; ECLM increased hepatocyte growth factor mRNA levels and Ki-67 labeled nuclei in the liver at 24 h; ECLM significantly reduced HIRI+PH-induced mortality. In conclusion, ECLM may prevent HIRI+PH-induced liver injury in part by suppressing various inflammatory responses and promoting liver regeneration.

TRIM14 Overexpression Induces Chemoresistance and Malignant Behaviors of Hepatocellular Carcinoma Cells by Activating the STAT3/HIF-1α Pathway

Members of the tripartite motif (TRIM)-containing protein family have been found to be involved in the progression of hepatocellular carcinoma (HCC). TRIM14 exerts a promotive impact on several cancers. This study aimed to explore the function and mechanism of TRIM14 in HCC. TRIM14 expression in HCC tissues and HCC cell lines was detected. The overexpression or knockdown model of TRIM14 was established in HCC cell lines. Cell Counting Kit-8 (CCK-8) assay, flow cytometry, Transwell assay, RT-PCR, Western blot, and immunofluorescence were performed to verify the influence of TRIM14 on cell proliferation, sensitivity to chemotherapy drugs, apoptosis, migration, invasion, and autophagy. A xenograft tumor model was used to confirm the impact of TRIM14 on tumor cell growth. As shown by the data, TRIM14 level was notably higher in the tumor tissues of HCC patients than in the adjacent tissues. The overall survival rate of patients with a high TRIM14 expression was relatively lower than that of patients with a low TRIM14 expression. TRIM14 upregulation enhanced the proliferation, autophagy, migration, and invasion of HCC cells and chemoresistant HCC cells and decreased apoptosis. TRIM14 knockdown contributed to the opposite effects. In in vivo experiments, TRIM14 upregulation bolstered tumor growth. Western blot analysis revealed that TRIM14 upregulation boosted signal transducer and activator of transcription3 (STAT3) and hypoxia-inducible factor-1alpha (HIF-1α) expression, and TRIM14 knockdown suppressed their expression. Moreover, repressing STAT3 and HIF-1α could mitigate the tumor-promoting role of TRIM14 in HCC cells. Overall, TRIM14 facilitated malignant HCC development and induced chemoresistance in HCC cells by activating the STAT3/HIF-1α axis.

Impact of Hypothermic Oxygenated Machine Perfusion on Hepatocellular Carcinoma Recurrence after Liver Transplantation

BACKGROUND

Machine perfusion may be able to mitigate ischemia-reperfusion injury (IRI), which increases hepatocellular carcinoma (HCC) recurrence after liver transplantation (LT). This study aimed to investigate the impact of dual-hypothermic oxygenated machine perfusion (D-HOPE) on HCC recurrence in LT.

METHODS

A single-center retrospective study was conducted from 2016 to 2020. Pre- and postoperative data of HCC patients undergoing LT were analyzed. Recipients of a D-HOPE-treated graft were compared to those of livers preserved using static cold storage (SCS). The primary endpoint was recurrence-free survival (RFS).

RESULTS

Of 326 patients, 246 received an SCS-preserved liver and 80 received a D-HOPE-treated graft (donation after brain death (DBD), n = 66; donation after circulatory death (DCD), n = 14). Donors of D-HOPE-treated grafts were older and had higher BMI. All DCD donors were treated by normothermic regional perfusion and D-HOPE. The groups were comparable in terms of HCC features and estimated 5-year RFS according to the Metroticket 2.0 model. D-HOPE did not reduce HCC recurrence (D-HOPE 10%; SCS 8.9%; p = 0.95), which was confirmed using Bayesian model averaging and inverse probability of treatment weighting-adjusted RFS analysis. Postoperative outcomes were comparable between groups, except for lower AST and ALT peak in the D-HOPE group.

CONCLUSIONS

In this single-center study, D-HOPE did not reduce HCC recurrence but allowed utilizing livers from extended criteria donors with comparable outcomes, improving access to LT for patients suffering from HCC.

Preservation of Mitochondrial Health in Liver Ischemia/Reperfusion Injury

Liver ischemia-reperfusion injury (LIRI) is a major cause of the development of complications in different clinical settings such as liver resection and liver transplantation. Damage arising from LIRI is a major risk factor for early graft rejection and is associated with higher morbidity and mortality after surgery. Although the mechanisms leading to the injury of parenchymal and non-parenchymal liver cells are not yet fully understood, mitochondrial dysfunction is recognized as a hallmark of LIRI that exacerbates cellular injury. Mitochondria play a major role in glucose metabolism, energy production, reactive oxygen species (ROS) signaling, calcium homeostasis and cell death. The diverse roles of mitochondria make it essential to preserve mitochondrial health in order to maintain cellular activity and liver integrity during liver ischemia/reperfusion (I/R). A growing body of studies suggest that protecting mitochondria by regulating mitochondrial biogenesis, fission/fusion and mitophagy during liver I/R ameliorates LIRI. Targeting mitochondria in conditions that exacerbate mitochondrial dysfunction, such as steatosis and aging, has been successful in decreasing their susceptibility to LIRI. Studying mitochondrial dysfunction will help understand the underlying mechanisms of cellular damage during LIRI which is important for the development of new therapeutic strategies aimed at improving patient outcomes. In this review, we highlight the progress made in recent years regarding the role of mitochondria in liver I/R and discuss the impact of liver conditions on LIRI.

Methods of Attenuating Ischemia-Reperfusion Injury in Liver Transplantation for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most frequent indications for liver transplantation. However, the transplantation is ultimately associated with the occurrence of ischemia-reperfusion injury (IRI). It affects not only the function of the graft but also significantly worsens the oncological results. Various methods have been used so far to manage IRI. These include the non-invasive approach (pharmacotherapy) and more advanced options encompassing various types of liver conditioning and machine perfusion. Strategies aimed at shortening ischemic times and better organ allocation pathways are still under development as well. This article presents the mechanisms responsible for IRI, its impact on treatment outcomes, and strategies to mitigate it. An extensive review of the relevant literature using MEDLINE (PubMed) and Scopus databases until September 2020 was conducted. Only full-text articles written in English were included. The following search terms were used: “ischemia reperfusion injury”, “liver transplantation”, “hepatocellular carcinoma”, “preconditioning”, “machine perfusion”.

Circ_0038467 regulates lipopolysaccharide-induced inflammatory injury in human bronchial epithelial cells through sponging miR-338-3p

Background

Pneumonia is a common acute lower respiratory infection in children and elders. Circular RNAs (circRNAs) have recently been uncovered to play important roles in pneumonia. However, the function and mechanism of circ_0038467 in pneumonia remain elusive.

Methods

Cell viability and apoptosis were determined using the Cell Counting Kit‐8 (CCK‐8) assay and flow cytometry, respectively. The levels of interleukin 6 (IL‐6), IL‐8 and IL‐1β were detected by enzyme‐linked immunosorbent assay (ELISA). Western blot analysis was performed to assess the expression of related proteins. Circ_0038467 was characterized by Ribonuclease R (RNase) digestion and subcellular localization assays. The levels of circ_0038467 and miR‐338‐3p were evaluated by quantitative real‐time polymerase chain reaction (qRT‐PCR). The direct interaction between circ_0038467 and miR‐338‐3p was validated by the dual‐luciferase reporter and RNA immunoprecipitation (RIP) assays.

Results

Our data indicated that lipopolysaccharide (LPS) induced an inflammatory injury in 16HBE cells by repressing cell viability and enhancing cell apoptosis and proinflammatory cytokines production. Circ_0038467 was upregulated and miR‐338‐3p was downregulated in LPS‐treated 16HBE cells. Circ_0038467 knockdown or miR‐338‐3p overexpression attenuated LPS‐induced 16HBE cell inflammatory injury. Moreover, circ_0038467 acted as a sponge of miR‐338‐3p in 16HBE cells. MiR‐338‐3p mediated the alleviated effect of circ_0038467 knockdown on LPS‐induced 16HBE cell inflammatory injury. Additionally, the Janus kinase/ signal transducer and activator of transcription 3 (JAK/STAT3) signaling pathway was involved in the circ_0038467/miR‐338‐3p axis‐mediated regulation in LPS‐induced 16HBE cell inflammatory injury.

Conclusions

The current work had led to the identification of circ_0038467 knockdown that alleviated LPS‐induced inflammatory injury in 16HBE cells at least partly through sponging miR‐338‐3p and regulating JAK/STAT3 pathway, highlighting novel molecular targets for the treatment of pneumonia.

COX-2 induces apoptosis-resistance in hepatocellular carcinoma cells via the HIF-1α/PKM2 pathway

The pyruvate kinase M2 isoform (PKM2) is a key component of aerobic glycolysis and has been reported to regulate apoptosis. However, it is unclear whether PKM2 is involved in cyclooxygenase‑2 (COX‑2) induced apoptosis‑resistance in hepatocellular carcinoma (HCC) cells. In the present study, it was observed that COX‑2 and PKM2 were significantly elevated in hepatocellular carcinoma tissues compared with adjacent liver tissues (P<0.05). Furthermore, their expression was positively associated with worse clinicopathological characteristics, which indicates poor prognosis in patients with HCC. COX‑2 knockdown significantly reduced the expression of PKM2 and hypoxia inducible factor‑1α (HIF‑1α) at the mRNA and protein levels in addition to inhibiting proliferation (P<0.05), whereas apoptosis was notably increased. Furthermore, HIF‑1α and PKM2‑knockdown increased cell apoptosis without inhibiting COX‑2 expression. PKM2 inhibition did not have a marked effect on COX‑2 and HIF‑1α expression. In conclusion, the results of the present study suggested that HIF‑1α/PKM2 pathway‑associated metabolic changes may facilitate COX‑2‑induced apoptosis resistance in HCC cells.

IL-6 and NFE2L2: A putative role for the hepatoprotective effect of N. Sativa, P. Ginseng and C. Sempervirens in AFB-1 induced hepatocellular carcinoma in rats

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P. Ginseng showed a prominent prophylactic effect in AFB-1 induced rat model.

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Hepatoprotective effects of extracts possibly mediated via IL-6, hs-CRP, SOD, NFE2L2.

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NFE2L2 play a pivotal role in this hepatoprotective effect of herbal extracts.

In this study, we investigated possible hepato-protective effects of N. Sativa, P. Ginseng, and C. Sempervirens in Aflatoxin B1 (AFB-1) induced hepatocellular carcinoma rat model.

Fifty-four male albino rats were randomly assigned to experimental groups. Alcoholic extracts of aforementioned herbs were administered orally for 28 days at different doses. IL-6, hs-CRP, MDA, SOD and NFE2L2 were determined using ELISA. Histopathological changes in treated groups were examined.

Herbal treatment significantly reduced IL-6, hs-CRP, and MDA (P < 0.001) whereas it significantly increased SOD (p < 0.001). C. Sempervirens 600 and N. Sativa 1000 increased NFE2L2 level compared to P. Ginseng 500 group (P value<0.01). Histopathological evaluation of treated groups showed different grades of healing of the liver.

This study confirms a beneficial hepatoprotective effect for aforementioned herbal extracts orally administered in rat model of AFB1 induced HCC. This effect is putatively mediated via modulation of inflammatory cytokines as well as amelioration of oxidative stress.

Ischemia-reperfusion injury and the risk of hepatocellular carcinoma recurrence after deceased donor liver transplantation

This study aimed to evaluate the effects of ischemia-reperfusion injury (IRI) on the risk of hepatocellular carcinoma (HCC) recurrence after liver transplantation. Data of 195 patients were retrospectively analysed. Post-reperfusion aspartate (AST), alanine transaminase, and lactate dehydrogenase (LDH) levels were the primary measures of IRI. Tumour recurrence was the primary endpoint. Post-reperfusion AST was a continuous risk factor for tumour recurrence in patients within Milan criteria (p = 0.035), with an optimal cut-off of 1896 U/L. Recurrence-free survival of patients within Milan criteria and post-reperfusion AST of <1896 and ≥1896 U/L was 96.6% and 71.9% at 5 and 3.7 years, respectively (p = 0.006). Additionally, post-reperfusion AST and LDH exceeding the upper quartile significantly increased the risk of HCC recurrence in patients within Milan criteria (p = 0.039, hazard ratio [HR] = 5.99 and p = 0.040, HR = 6.08, respectively) and to a lesser extent, in patients within Up-to-7 criteria (p = 0.028, HR = 3.58 and p = 0.039, HR = 3.33, respectively). No other significant IRI effects were found in patients beyond the Up-to-7 criteria and in analyses stratified for independent risk factors for recurrence: tumour number and differentiation, alpha-fetoprotein, and microvascular invasion. Thus, IRI exerts major negative effects on the risk of HCC recurrence after liver transplantation in patients within standard and extended criteria.

miR-1-3p and miR-206 sensitizes HGF-induced gefitinib-resistant human lung cancer cells through inhibition of c-Met signalling and EMT

Hepatocyte growth factor (HGF) overexpression is an important mechanism in acquired epidermal growth factor receptor (EGFR) kinase inhibitor gefitinib resistance in lung cancers with EGFR activating mutations. MiR-1-3p and miR-206 act as suppressors in lung cancer proliferation and metastasis. However, whether miR-1-3p and miR-206 can overcome HGF-induced gefitinib resistance in EGFR mutant lung cancer is not clear. In this study, we showed that miR-1-3p and miR-206 restored the sensitivities of lung cancer cells PC-9 and HCC-827 to gefitinib in present of HGF. For the mechanisms, we demonstrated that both miR-1-3p and miR-206 directly target HGF receptor c-Met in lung cancer. Knockdown of c-Met mimicked the effects of miR-1-3p and miR-206 transfections Meanwhile, c-Met overexpression attenuated the effects of miR-1-3p and miR-206 in HGF-induced gefitinib resistance of lung cancers. Furthermore, we showed that miR-1-3p and miR-206 inhibited c-Met downstream Akt and Erk pathway and blocked HGF-induced epithelial-mesenchymal transition (EMT). Finally, we demonstrated that miR-1-3p and miR-206 can increase gefitinib sensitivity in xenograft mouse models in vivo. Our study for the first time indicated the new function of miR-1-3p and miR-206 in overcoming HGF-induced gefitinib resistance in EGFR mutant lung cancer cell.