Hepatocyte growth factor gene therapy prevents radiation-induced liver damage

Proteomic Analysis of Radiation-Induced Acute Liver Damage in a Rabbit Model

Radiation-induced liver damage (RILD) has become a limitation in radiotherapy for hepatocellular carcinoma. We established a rabbit model of RILD by CyberKnife. Electron microscopy analysis revealed obvious nuclear atrophy and disposition of fat in the nucleus after irradiation. We then utilized a mass spectrometry-based label-free relative quantitative proteomics approach to compare global proteomic changes of rabbit liver in response to radiation. In total, 2365 proteins were identified, including 338 proteins that were significantly dysregulated between irradiated and nonirradiated liver tissues. These differentially expressed proteins included USP47, POLR2A, CSTB, MCFD2, and CSNK2A1. Real-time polymerase chain reaction confirmed that USP47 and CABLES1 transcripts were significantly higher in irradiated liver tissues, whereas MCFD2 and CSNK2A1 expressions were significantly reduced. In Clusters of Orthologous Groups of proteins analysis, differentially expressed proteins were annotated and divided into 24 categories, including posttranslational modification, protein turnover, and chaperones. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the enriched pathways in dysregulated proteins included the vascular endothelial growth factors (VEGF) signaling pathway, the mitogen-activated protein kinase (MAPK) signaling pathway, and the adipocytokine signaling pathway. The identification of proteins and pathways is crucial toward elucidating the radiation response process of the liver, which may facilitate the discovery of novel therapeutic targets.

Nigella sativa oil modulates the therapeutic efficacy of mesenchymal stem cells against liver injury in irradiated rats

Stem cell transplantation is a novel strategy for regenerative medicine in liver disease. This study was conducted to explore the modulatory effect of Nigella sativa oil (NSO) on the therapeutic potential of mesenchymal stem cells (MSCs) against irradiation-induced liver damage in rats. Liver damage was induced by a total body exposure to a single dose of 7Gy. NSO (2mg/kg/day) was then given orally for 4 consecutive weeks starting 24h after irradiation with or without a single intravenous MSCs administration, then rats were sacrificed four weeks after exposure to γ radiation. Data revealed that irradiation elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in serum, increased hepatic malondialdehyde (MDA) content and reduced hepatic superoxide dismutase (SOD) activity. Furthermore, it caused elevation in pro-inflammatory mediators such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) associated with reduction in anti-inflammatory cytokine interleukin-10 (IL-10) and it increased fibrogenic marker transforming growth factor-β (TGF-β) in liver tissues. It was observed that combined NSO/MSCs therapy provided more beneficial tissue repair comparable to MSCs alone as demonstrated by modulating the tested parameters. Finally, these results were confirmed by histopathological examination. In conclusion, dual therapy with NSO and MSCs could serve as a promising approach for alleviating radiation-induced liver injury in patients with radiotherapy.

Prevention and treatment of complications of selective internal radiation therapy: Expert guidance and systematic review

Selective internal radiation therapy (or radioembolization) by intra-arterial injection of radioactive yttrium-90-loaded microspheres is increasingly used for the treatment of patients with liver metastases or primary liver cancer. The high-dose beta-radiation penetrates an average of only 2.5 mm from the source, thus limiting its effects to the site of delivery. However, the off-target diversion of yttrium-90 microspheres to tissues other than the tumor may lead to complications. The most prominent of these complications include radiation gastritis and gastrointestinal ulcers, cholecystitis, radiation pneumonitis, and radioembolization-induced liver disease, which may occur despite careful pretreatment planning. Thus, selective internal radiation therapy demands an expert multidisciplinary team approach in order to provide comprehensive care for patients. This review provides recommendations to multidisciplinary teams on the optimal medical processes in order to ensure the safe delivery of selective internal radiation therapy. Based on the best available published evidence and expert opinion, we recommend the most appropriate strategies for the prevention, early diagnosis, and management of potential radiation injury to the liver and to other organs. (Hepatology 2017;66:969-982).

Glibenclamide, a diabetic drug, prevents acute radiation induced liver injury of mice via up-regulating intracellular ROS and subsequently activating Akt-NF-κB pathway

BACKGROUND

Acute radiation-induced liver injury is a limitation for hepatoma radiotherapy. Come so far the clinical treatments are insufficient. The effective, specific, low toxicity and novel drugs are in powerful need. Glibenclamide is a common hypoglycemic. Some studies have revealed its relation with intracellular reactive oxygen species, the crucial mediator to radiation injury. This study is aimed to investigate if glibenclamide could act on the acute radiation-induced liver injury.

RESULTS

Glibenclamide mitigated acute radiation-induced liver injury of mice, indicating as regression of hepatocellular edema, reduction of hepatic sinusoid, decline in serum ALP level and reduction of hepatocellular apoptosis. Pretreatment of glibenclamide reduced the radiosensitivity of NCTC-1469 cells. In mechanism, glibenclamide elevated cells membrane potential to up-regulate intracellular reactive oxygen species. The increased reactive oxygen species subsequently activated Akt-NF-κB pathway to promote survival of irradiated cells.

METHODS

BALB/C male mice were intraperitoneal injected with glibenclamide 1 hour before hepatic irradiation. At designed time points the livers were taken to make histological study and bloods were collected to measure serum transaminase. With/without glibenclamide pretreatment the irradiated NCTC-1469 cells were tested apoptosis, viability and proliferation. By western blotting the involved molecules were detected.

CONCLUSIONS

Glibenclamide, prevents acute radiation-induced liver injury of mice via up-regulating intracellular reactive oxygen species and subsequently activating Akt-NF-κB pathway.

Hepatocyte growth factor gene-modified adipose-derived mesenchymal stem cells ameliorate radiation induced liver damage in a rat model

Liver damage caused by radiotherapy is associated with a high mortality rate, but no established treatment exists. Adipose-derived mesenchymal stem cells (ADSCs) are capable of migration to injured tissue sites, where they aid in the repair of the damage. Hepatocyte growth factor (HGF) is critical for damage repair due to its anti-apoptotic, anti-fibrotic and cell regeneration-promoting effects. This study was performed to investigate the therapeutic effects of HGF-overexpressing ADSCs on radiation-induced liver damage (RILD). ADSCs were infected with a lentivirus encoding HGF and HGF-shRNA. Sprague-Dawley (SD) rats received 60Gy of irradiation to induce liver injury and were immediately given either saline, ADSCs, ADSCs + HGF or ADSCs + shHGF. Two days after irradiation, a significant reduction in apoptosis was observed in the HGF-overexpressing ADSC group compared with the RILD group, as assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. Scanning electron microscopy showed chromatin condensation after irradiation, which was ameliorated in the group that received ADSCs and was reversed in the group that received HGF-overexpressing ADSCs. HGF-overexpressing ADSCs ameliorated radiation- induced liver fibrosis through down regulation of α-SMA and fibronectin. Hepatocyte regeneration was significantly improved in rats treated with ADSCs compared with rats from the RILD group), as assessed by Ki-67 immunohistochemistry. Rats that received HGF-overexpressing ADSCs showed an even greater level of hepatocyte regeneration. HGF-overexpressing ADSCs completely blocked the radiation-induced increase in the enzymes ALT and AST. The effect of mitigating RILD was compromised in the ADSC + shHGF group compared with the ADSC group. Altogether, these results suggest that HGF-overexpressing ADSCs can significantly improve RILD in a rat model, which may serve as a valuable therapeutic alternative.

Gene electrotransfer clinical trials

Plasmid or non-viral gene therapy offers an alternative to classic viral gene delivery that negates the need for a biological vector. In this case, delivery is enhanced by a variety of approaches including lipid or polymer conjugation, particle-mediated delivery, hydrodynamic delivery, ultrasound or electroporation. Electroporation was originally used as a laboratory tool to deliver DNA to bacterial and mammalian cells in culture. Electrode development allowed this technique to be modified for in vivo use. After preclinical therapeutic studies, clinical delivery of cell impermeant chemotherapeutic agents progressed to clinical delivery of plasmid DNA. One huge benefit of this delivery technique is its malleability. The pulse protocol used for plasmid delivery can be fine-tuned to control the levels and duration of subsequent transgene expression. This fine-tuning allows transgene expression to be tailored to each therapeutic application. Effective and appropriate expression induces the desired clinical response that is a critical component for any gene therapy. This chapter focuses on clinical trials using in vivo electroporation or electrotransfer as a plasmid delivery method. The first clinical trial was initiated in 2004, and now more than fifty trials use electric fields for gene delivery. Safety and tolerability has been demonstrated by several groups, and early clinical efficacy results are promising in both cancer therapeutic and infectious disease vaccine applications.

The clinical value of serum hepatocyte growth factor levels in patients undergoing primary radiotherapy for glioma: effect on progression-free survival

Hepatocyte growth factor (HGF) has been shown to be overexpressed in gliomas, and high-grade gliomas (glioblastoma multiforme) express more HGF than lower-grade astrocytoma, and HGF enhances their resistance to radiotherapy. To examine the effect of serum HGF levels on the likelihood of response to radiotherapy and the disease-free survival in patients with glioma, the blood samples of the patients were collected before commencing treatment and serum HGF was measured by quantitative ELISA in 48 patients with glioma grade I-IV, and all patients underwent primary conventionally fractionated radiotherapy. For statistical analysis, SPSS Version 13.0 software was used. Thirty-eight of the 48 patients had a response to treatment, and ten patients had persistent disease at 3 months. Overall, the median serum HGF level was 1,219.5 pg/ml (range 650.4-2,264.7 pg/ml). Eight patients with local failure had HGF levels >1,219.5 pg/ml, and 28 patients with response had serum HGF level of ≤ 1,219.5 pg/ml (P = 0.01). The median time to progression was 6 months in patients with HGF level of >1,219.5 pg/ml compared with 17 months in patients with HGF level of ≤ 1,219.5 pg/ml (log-rank, P = 0.041). In multivariate analysis, serum HGF, the KPS, tumour size and pathological grade, but not the patient's age, gender and oligodendroglial component influenced the progression-free survival. Elevated pre-therapeutic serum HGF levels are associated with poor response and a shorter time to progression in patients with glioma undergoing primary radiotherapy.

Long-term pathological and immunohistochemical features in the liver after intraoperative whole-liver irradiation in rats

Radiation therapy (RT) has become particularly important recently for treatment of liver tumors, but there are few experimental investigations pertaining to radiation-induced liver injuries over long-term follow-up periods. Thus, the present study examined pathological liver features over a 10-month period using an intraoperative whole-liver irradiation model. Liver function tests were performed in blood samples, whereas cell death, cell proliferation, and fibrotic changes were evaluated pathologically in liver tissues, which were collected from irradiated rats 24 h, 1, 2, 4 and 40 weeks following administration of single irradiation doses of 0 (control), 15 or 30 Gy. The impaired liver function, increased hepatocyte number, and decreased apoptotic cell proportion observed in the 15 Gy group, but not the 30 Gy group, returned to control group levels after 40 weeks; however, the Ki-67 indexes in the 15 Gy group were still higher than those in the control group after 40 weeks. Azan staining showed a fibrotic pattern in the irradiated liver in the 30 Gy group only, but the expression levels of alpha smooth muscle actin (α-SMA) and transforming growth factor-beta 1 (TGF-β1) in both the 15 and 30 Gy groups were significantly higher than those in the control group (P < 0.05). There were differences in the pathological features of the irradiated livers between the 15 Gy and 30 Gy groups, but TGF-β1 and α-SMA expression patterns supported the gradual progression of radiation-induced liver fibrosis in both groups. These findings will be useful in the future development of protective drugs for radiation-induced liver injury.

Protection against radiation-induced hematopoietic damage in bone marrow by hepatocyte growth factor gene transfer

PURPOSE

To investigate whether adenovirus-mediated delivery of the human hepatocyte growth factor (HGF) gene could prevent radiation-induced hematopoietic damage.

MATERIALS AND METHODS

Thirty C57BL/6 mice were randomized into three groups, in which phosphate buffer saline (PBS), mock adenovirus vector (Ad-null) or adenovirus vector containing HGF (Ad-HGF) were injected into the tail vein of each group, respectively. After 48 hours, the mice received a single irradiation dose of 6.5 Gy (60)Co gamma rays. Blood samples were extracted via the tail vein at day 0, 4, 7, 10, 14, 21, 24 and 30 after irradiation, for red blood cell (RBC) and white blood cell (WBC) and cluster of differentiation4 (CD4)/cluster of differentiation8 (CD8) ratio assessment. At weekly intervals following irradiation, serum erythropoietin (EPO), Interleukin-6 (IL-6) and Interferon-gamma (IFN-γ) levels were measured using enzyme-linked immunosorbent assay (ELISA). On post-irradiation day 30, the mice were autopsied and erythroid burst-forming units (BFU-E) were evaluated.

RESULTS

Adenovirus-mediated HGF gene transfer could increase human HGF level in serum and have a significant elevation in RBC and WBC count. Ad-HGF increased EPO and IL-6 levels and prompted BFU-E formation. Ad-HGF decreased radiation- induced micronucleus frequency in the mouse bone marrow (BM). Most evidence of radiation-induced hematopoietic damage was observed morphologically in bone marrow specimen four weeks after irradiation. Ad-HGF protected against radiation-induced BM failure and increased survival. Finally, Ad-HGF increased the thymic index and enhanced immune function in the irradiated C57BL/6 mice.

CONCLUSIONS

This is the first report to date that demonstrates the potential of HGF gene transfer to prevent radiation-induced hematopoietic damage.

Radiation damage and radioprotectants: new concepts in the era of molecular medicine

Exposure to ionising radiation results in mutagenesis and cell death, and the clinical manifestations depend on the dose and the involved body area. Reducing carcinogenesis in patients treated with radiotherapy, exposed to diagnostic radiation or who are in certain professional groups is mandatory. The prevention or treatment of early and late radiotherapy effects would improve quality of life and increase cancer curability by intensifying therapies. Experimental and clinical data have given rise to new concepts and a large pool of chemical and molecular agents that could be effective in the protection and treatment of radiation damage. To date, amifostine is the only drug recommended as an effective radioprotectant. This review identifies five distinct types of radiation damage (I, cellular depletion; II, reactive gene activation; III, tissue disorganisation; IV, stochastic effects; V, bystander effects) and classifies the radioprotective agents into five relevant categories (A, protectants against all types of radiation effects; B, death pathway modulators; C, blockers of inflammation, chemotaxis and autocrine/paracrine pathways; D, antimutagenic keepers of genomic integrity; E, agents that block bystander effects). The necessity of establishing and funding central committees that guide systematic clinical research into evaluating the novel agents revealed in the era of molecular medicine is stressed.

Hepatocyte growth factor in lung repair and pulmonary fibrosis

Pulmonary remodeling is characterized by the permanent and progressive loss of the normal alveolar architecture, especially the loss of alveolar epithelial and endothelial cells, persistent proliferation of activated fibroblasts, or myofibroblasts, and alteration of extracellular matrix. Hepatocyte growth factor (HGF) is a pleiotropic factor, which induces cellular motility, survival, proliferation, and morphogenesis, depending upon the cell type. In the adult, HGF has been demonstrated to play a critical role in tissue repair, including in the lung. Administration of HGF protein or ectopic expression of HGF has been demonstrated in animal models of pulmonary fibrosis to induce normal tissue repair and to prevent fibrotic remodeling. HGF-induced inhibition of fibrotic remodeling may occur via multiple direct and indirect mechanisms including the induction of cell survival and proliferation of pulmonary epithelial and endothelial cells, and the reduction of myofibroblast accumulation.

Hepatocyte growth factor in lung repair and pulmonary fibrosis

Pulmonary remodeling is characterized by the permanent and progressive loss of the normal alveolar architecture, especially the loss of alveolar epithelial and endothelial cells, persistent proliferation of activated fibroblasts, or myofibroblasts, and alteration of extracellular matrix. Hepatocyte growth factor (HGF) is a pleiotropic factor, which induces cellular motility, survival, proliferation, and morphogenesis, depending upon the cell type. In the adult, HGF has been demonstrated to play a critical role in tissue repair, including in the lung. Administration of HGF protein or ectopic expression of HGF has been demonstrated in animal models of pulmonary fibrosis to induce normal tissue repair and to prevent fibrotic remodeling. HGF-induced inhibition of fibrotic remodeling may occur via multiple direct and indirect mechanisms including the induction of cell survival and proliferation of pulmonary epithelial and endothelial cells, and the reduction of myofibroblast accumulation.

Human CD34+ cells mobilized by granulocyte colony-stimulating factor ameliorate radiation-induced liver damage in mice

Introduction

On the basis of the recently recognized potential of hematopoietic stem cells (HSCs) to give rise to hepatocytes, we have assessed the potential of granulocyte colony-stimulating factor (G-CSF)-mobilized bone marrow-derived CD34⁺ HSCs to contribute to faster recovery and promote regeneration process after acute liver injury by radiation.

Methods

G-CSF-mobilized CD34⁺ HSCs (1 × 10⁵ cells per mouse) were injected via tail vein in the irradiated femal nonobese diabetic/severe combined immunodeficient mice. Irradiated control animals received only saline infusion.

Results

The mobilized CD34⁺ HSCs significantly ameliorated radiation-induced liver damage. In the liver of recipient mice killed 21 days after irradiation, human albumin⁺ Y-chromosome⁺ hepatocyte-like cells, or human cytokeratin⁺ Y-chromosome⁺ hepatocyte-like cells formed cords of hepatocytes, occupied ~30% of the 4-μm section surrounding portal tracts. Furthermore, human-specific albumin mRNA expressed in the liver and human albumin was detected in the serum only in the CD34⁺ HSC-treated mice.

Conclusions

Treatment with G-CSF-mobilized CD34⁺ HSCs from bone marrow into peripheral blood could significantly promote tissue reparation after acute liver injury by radiation in mice, possibly by the ability of CD34⁺ HSCs to generate hepatocytes. So mobilization of CD34⁺ HSCs might offer a novel therapeutic approach for the treatment of radiation-induced complications after radiotherapy or other acute liver diseases in humans.

Inhibition of radiation-induced apoptosis via overexpression of SMP30 in Smad3-knockout mice liver

Apoptosis occurs early after irradiation and may be a good indicator of radiation damages. Since elevated levels of TGF-beta are associated with radiation-induced inflammation, the null mice of Smad3, a key downstream mediator of TGF-beta, show accelerated healing of irradiated injury. In order to evaluate resistance to radiation-induced liver injuries in Smad3-null mice, we determined the occurrence of apoptosis and the expression of senescence marker protein-30 (SMP30), as an anti-apoptotic marker, after irradiation to the liver. The livers of Smad3-mutant mice were exposed to local irradiation of 15 gray, from a (60)Co-gamma radiation. One week after irradiation, in Smad3-KO mice, radiation-induced apoptosis was at lower levels compared to those of irradiated WT mice. These findings were well matched with the expression of CYP2E1, which plays a role in hepatic injuries produced by oxidative stress. In addition, antioxidant related protein, the SMP30 levels were reduced by gamma irradiation in both groups. Interestingly, the increased expression of SMP30 expression in Smad3-KO mice liver was preserved at a higher level than that of the WT mice after irradiation. Therefore, these results suggest that the interruption of TGF-beta signaling by deletion of Smad3 brings about inhibition of hepatic apoptosis after ionizing irradiation. Moreover, the protective effect to ionizing radiation might be in correlation with the overexpression of SMP30 in the Smad3-null mice, which may act as an anti-apoptotic signaling molecule. The alteration of SMP30 by interruption of Smad3 might be a useful therapeutic target and diagnostic marker for radiation-induced liver damages.

RETRACTED: Radiation-enhanced hepatocyte growth factor secretion in malignant glioma cell lines

BACKGROUND

Postoperative radiotherapy is the standard treatment for patients with a malignant glioma. However, a malignant glioma is radioresistant and almost always recurs, even after a high dose of radiation. A malignant glioma is characterized by its proliferation, invasion and neoangiogenesis, which can be attributed to the high levels of HGF. The scope of this study is to investigate HGF secretion by malignant glioma cells with different radiosensitivity after irradiation.

METHODS

Three human malignant glioma cell lines (U251, U251-NG2, and BT325) were irradiated with single doses of 0, 5, 10, and 20 grays of gamma-rays from a (137)Cs source. Hepatocyte growth factor levels in medium were measured by ELISA at 24, 48, and 72 hours after radiation. Cell survival was measured by the proliferation-based assay (XTT assay) 7 days after irradiation.

RESULTS

After a single dose radiation, the HGF levels showed a dose-dependent increase in U251, U251-NG2, and BT325 glioma cells. Both baseline and radiation-enhanced HGF levels were about 10-fold higher in BT325 compared to U251 and U251-NG2 cells. In addition, in the XTT assay, the BT325 was more radioresistant than both U251 and U251-NG2 cell lines (dose modifying factor = 1.5 and 1.6, respectively).

CONCLUSION

Irradiation-enhanced HGF secretion in all 3 tested glioma cell lines (up to 7 times basal levels). It is tempting to associate the radiation-enhanced HGF secretion with an increased angiogenic potential of the tumor, which may be a factor in radioresistance.

Anti-apoptotic effect of hepatocyte growth factor from actinomycin D in hepatocyte-derived HL7702 cells is associated with activation of PI3K/Akt signaling

Actinomycin D (ActD) is a well-known cytotoxic chemotherapeutic reagent and the prevention of ActD-induced apoptotic cell death has been an attractive issue for biomedical investigators. Since phosphatidylinositol-3 kinase (PI3K)/Akt pathway is essential for cell survival, the present study has examined whether the preventive effect of hepatocyte growth factor (HGF) on ActD-induced apoptotic cell death in a human hepatocyte-derived cell line (HL7702) is associated with PI3K/Akt activation. Apoptotic cell death was measured by several methods including Hoechst 33342 staining, DNA fragmentation, and flow cytometry. We found that ActD caused a significant increase in apoptotic cell death, an effect significantly prevented by pre-addition of HGF in the cultures. HGF was found to significantly activate Akt phosphorylation while pre-treatment with PI3K specific inhibitor wortmannin further enhanced ActD-induced apoptotic effect, and also significantly prevented HGF's protection against ActD-induced apoptosis. These results suggest that HGF's prevention of ActD-induced apoptotic cell death in HL7702 cells is associated with the activation of PI3K/Akt signaling.