Volume 25, numbers 39-40,
28 september 2007
, pages 6911-6921
Author links open the overlay panel, , , ,
In the following study, we prepared a double-stranded miniprotein where each strand contains three linear repeats of its own gonadotropin-releasing hormone (GnRH) peptide3), ofjoint regionhumanIgG1(hinge) and T helper epitope of measlesprotein viruses(MVP). di-GnRH3hinge MVP miniprotein was conjugated to a purified recombinantheat shock protein 65(Hsp65) fromMycobacterium bovisand used to immunize BALB/cmicejacket withsubcutaneous injectionBacillus Calmette-Guerin (BCG) in the absence of adjuvants. After successfully producing anti-GnRH antibodies, mice were inoculated with H22 cells assolide tumor. The results showed that serum testosterone levels decreased significantly after GnRH was inhibited with anti-GnRH antibodies (P<0.01) itesticlereduced weight (P<0,05) uGnRH3hinge-MVP-Hsp65-immunized mice. Mean tumor weight in GnRH-treated mice3hinge MVP Hsp65 was significantly lower than in mice treated with saline alone (neutral control,P<0.001), or less than in Hsp65-treated mice (negative control,P<0.005). The data presented here showed that GnRH3hinge-MVP-Hsp65 could significantly attenuate liver tumor progression in mice transplanted with H22 cells, and could developpalliative treatmentpatients with hepatocellular carcinoma (HCC) in the future.
Hepatocellular carcinoma (HCC) is the fifth most common malignant tumor in the world. In China, it is the second leading cause of cancer death in men and the third in women , . The pathogenesis of HCC is still poorly understood, and what we do know is that some factors are associated with an increased risk of developing cancer. Several risk factors are believed to play a role in HCC . Epidemiological studies on HCC show a clear disadvantage of the male gender. For example, in Asian countries, the ratio of men to women ranges from 2.4 to 4.3 . Not only do men develop HCC, they also die more easily than women: in fact, the prognosis for the disease is more malignant in men than in women, and men have poorer survival and more disease recurrence after treatment . Due to their marked male predominance, androgens have been investigated as potential factors that can induce or at least promote liver carcinogenesis, and this hypothesis is also supported by the ability of androgens to induce liver neoplasms in experimental models , ,  . Elevated levels of serum testosterone (T) and T to estradiol (E2) ratio has been proposed to predict an increased risk of HCC in cirrhotic male patients . On the other hand, estrogens are involved in the regulation of hepatocyte proliferation and estrogen receptors (ER) are present in livers with cirrhosis and HCC. In fact, after partial hepatectomy in humans, there is a 'feminization' of the liver microenvironment . As a result, both the presence of male sex hormones and the feminizing effect caused by cirrhosis have been blamed, at least in part, for the development of HCC. It has therefore been suggested that changes in sex hormones may play a role in liver carcinogenesis . Palliative treatment of liver cancer patients with antihormones has been widely used in the past. However, the molecular mechanism underlying the action of sex steroids on hepatocarcinoma cells has not yet been fully elucidated, nor have endocrine discriminants been satisfactorily evaluated for adequate characterization of liver cancer. Recently, both the androgen receptor (AR) protein and its mRNA have been found to be elevated in liver tumors from male individuals , which are thought to be involved in male predominance. Many researchers have reported that sex hormones can cause DNA alteration and growth factor changes in liver cells .
Gonadotropin-releasing hormone (GnRH) is an endogenous hormone containing 10 amino acid residues. GnRH plays a key role in the regulation of the pituitary-gonadal axis: it selectively stimulates the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the anterior pituitary to promote ovarian follicular maturation and spermatogenesis . This feature has attracted widespread attention due to its enormous potential as an anti-hormone reagent. While GnRH analogs have been used clinically to treat a number of hormone-dependent diseases, they often require large, toxic, and expensive doses of the drug to be administered. Induction of an immune response against GnRH could therefore prove to be less toxic and less expensive in the treatment of such hormone-related disorders . In our lab, we successfully prepared a synthetic mini-protein consisting of three GnRH repeats (GnRH3), a T helper epitope of the measles virus protein (MVP) and the hinge region of human IgG1 (hinge), called GnRH3-hinges-MVP. Double-chain miniprotein (di-GnRH3hinge MVP) is obtained by oxidation of GnRH3-hinges-MVP. GnRH miniprotein3hinge MVP successfully induced an anti-GnRH immune response in rats in the presence of Freund's adjuvant. However, Freund's adjuvant is not allowed in the human body. To address this issue, we investigated the use of di-GnRH3hinge MVP conjugated to heat shock protein 65 (Hsp65) is derived fromMycobacterium bovisBacillus Calmette-Guerin (M. bovisBCG) to induce anti-GnRH antibodies in male BALB/c mice.
In addition, there is ample evidence for the expression of GnRH and its receptors in tissues outside the pituitary gland, particularly in a range of tumors not only of reproductive origin, including breast , prostate , ovary  and endometrium [ 1]. 18], but also non-reproductive tissues of liver , kidney , pancreas . There is increasing research on the existence of GnRH and its binding sites in human hepatocarcinoma tissue and its cell lines , , . Although the function of the GnRH autocrine system in liver tumors has not been elucidated, it is believed that GnRH plays an important role in the promotion and progression of liver tumors and will become the target of therapeutic approaches against HCC. Based on this, it is speculated that the biological effect of GnRH and GnRH analogues on liver tumors may lie in two aspects: one blocks the secretion of sex hormones by inhibiting the function of the pituitary-gonadal axis, the other causes a specific signal by the direct activation of GnRH binding sites anchored on the surface of hepatocarcinoma cells. Among the various approaches explored to control GnRH activity or treat GnRH-related diseases, active immunization using peptide-based vaccines has gained wide acceptance. The aim of this study was to confirm the effect of recombinant peptide vaccine against GnRH on H22 liver tumor in male BALB/c mice.
Fragments of sections
The murine hepatoma cell line H22 was kindly provided by the Shanghai Institute of Materia Medica, CAS of mouse ascites, which were heterogeneous cells with a higher declination of spreading through lymphatic vessels.
Male BALB/c mice, 4-5 weeks old and weighing 15-20 g, free of specific pathogens, were obtained from the Laboratory Animal Center of the Shanghai Institute of Biological Sciences, CAS, and housed in a laminar airflow chamber under pathogen-free conditions according to schedule 12 hours light/12 hours dark. Theirs
To increase GnRH production3hinge MVP miniprotein, we select the C-terminal sequenceL. asparaginaza(ansB-C) originates from the chromosomeE coliBL21 as remainder. The ansB-C DNA fragment and an acid-labeled asparagine-proline linker (Asp-Pro) were placed at the 3' end of the T7 Φ10 promoter in the expression vector pET-28a (Novagen), designated pED. The DNA sequence encoding GnRH joint MVP obtained by double primer PCR was inserted into both ends of the pED (BamHI at the 5' end and
In previous studies, we found that GnRH3hinge MVP miniprotein in Freund's adjuvant elicited a marked anti-GnRH response in both male and female rats. Although Freund's adjuvant is capable of enhancing the immune response against poorly immunogenic epitopes, it cannot be used in the human body due to its toxicity. Recent reports indicate that mycobacterial heat shock protein 65 kDa (Hsp65) shows strong immunogenicity and contains strong T cell epitopes. Hsp65 can be used so easily and safely
This work was supported by the Committee of the National Natural Science Foundation of China (Grant No. 30500458).
- H.M.Vordermajeret al.
Improved immunogenicity of DNA vaccination with mycobacterial Hsp65 against bovine tuberculosis through protein elevation
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Priming of CD8+ CTL effector cells in mice by immunization with stress protein fusion and influenza virus nucleoprotein molecule
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Increased expression of hepatic androgen receptors in female rats during liver carcinogenesis with diethylnitrosamine. Possible connection with the development of liver tumors
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Response to cyproterone acetate treatment in primary hepatocellular carcinoma is associated with a decrease in free 5α-dihydrotestosterone
Eur J Cancer Clinic Oncol
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Estrogen regulation of transforming growth factor-α in ovarian cancer
J Steroid Biochem Mol Biol
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High rates of hepatocellular carcinoma in cirrhotic patients with high proliferative liver cell activity
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Female sex hormone receptor status in advanced hepatocellular carcinoma and outcome after surgical resectionSee Alsoa 1 adrenergic receptor - PKC - Pyk2 - Src signaling enhances L-type Ca 2+ channel Approx C 1.2 activity and long-term potentiation in rodents
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Endocrine treatment of hepatocellular carcinoma, is there evidence of benefit?
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Effect of antiandrogen treatment on chemical hepatocarcinogenesis in rats
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Trends in survival of patients with hepatocellular carcinoma between 1977 and 1996 in the United States.
Cancer mortality in 33 countries of the world (1953-1987)
Investigation of mortality spectrum characteristics and typical composition of malignant tumors in China
Chin J Oncol
Epidemiological features and risk factors of hepatocellular carcinoma
J Gastroenterol Hepatol
Effect of neonatal castration on liver tumor inductionN-2-fluorenylacetamide in lactating BALB/c mice
Androgen receptor-dependent but cell-independent stimulation of mouse hepatocarcinogenesis by testosterone
Proc Natl Acad Sci VS
Serum testosterone: estradiol ratio and the development of hepatocellular carcinoma in men with cirrhosis
Hepatic regeneration and growth factors
J Surg Oncol Suppl
Hepatocellular carcinoma and sex hormones
Heterogeneity in androgen receptor levels and growth response to dihydrotestosterone in sublines derived from a human hepatocellular carcinoma line (KYN-1)
Curr Opin Pharmacol Rev
Anti-gonadotropin-releasing hormone vaccines and their possible use in the treatment of hormone-responsive cancers
Biological Medicines Rev
Effects of fadrozole and leuprorelin acetate on aromatase activity and cell proliferation in human breast cancer cell line (SK-BR-3)
Int J Clin Oncol
Luteinizing hormone-releasing hormone receptor in human prostate cancer cells: expression of messenger ribonucleic acid, molecular size and signal transduction pathway
Cellular mechanisms of growth inhibition of a human epithelial ovarian cancer cell line by the LH-releasing hormone antagonist cetrorelix
J Clin Endocrinol Metab
Expression of gonadotropin-releasing hormone receptor II (GnRH-II) in human endometrial and ovarian cancer cells and effects of GnRH-II on tumor cell proliferation
J Clin Endocrinol Metab
Expression of messenger RNA for gonadotropin-releasing hormone and its receptor in human cancer cell lines
Inhibition of Caki-I growth of human renal adenocarcinoma in vivo by the luteinizing hormone-releasing hormone antagonist cetrorelix, the somatostatin analogue RC-160 and the bombesin antagonist RC-3940-II
Preparation of a peptide vaccine against GnRH by an asparaginase-based bioprocess system
Excerpt from the quote:
Several strategies, such as linear alignment of haptens, use of powerful adjuvants, retro-inverso strategies, and fusion or conjugation with defined T helper epitopes and/or carrier proteins, have been shown to be useful in eliciting strong immune responses [25-27]. Our previous study also proved these concepts [17,25,28,29]. Since the conventional chemical synthesis of polypeptides such as GhMNR is very time consuming, environmentally unfriendly and expensive, genetic engineering has become an attractive alternative method for the production of these peptide vaccines.
GnRH is a promising target in hormone-dependent cancer immunotherapy. In our previous study, we used a peptide vaccine GhM (GnRH3hinge MVP) using an asparaginase-based bioprocess system. Active immunization with GhM in the presence of CFA/IFA induced a strong humoral response. In this study, the high affinity NRLLLTG motif for the nanoparticle carrier VLP HBcΔ-SBD was fused to the C-terminus of GhM to create a novel peptide vaccine GhMNR (GnRH3hinges-MVP-NRLLLTG). The ansB-C-GhMNR fusion protein is controlled by the strong T7lac promoter and efficiently expressed as inclusion bodies after lactose induction and then purified by cell disruption, washing and cold ethanol fractionation. After 72 hours of hydrolysis, GhMNR was released from the ansB-C fusion partner and purified by CM52 cation exchange chromatography. These results suggest that the bioprocess system is suitable for large-scale expression and purification of the GhMNR peptide vaccine and even some other proteins or peptides that may be important for industrial or laboratory purposes.
Active immunization with recombinant GnRH fusion protein in boars reduces both testicular development and pituitary GnRH receptor mRNA expression levels
2010, The Science of Animal Reproduction
Immunization with recombinant maltose binding protein gonadotropin-releasing hormone (MBP-GnRH6) altered both testicular development and pituitary GnRH receptor (GnRHR) gene transcription in boars. Scrotal measurements and blood samples were taken at 4 week intervals after immunization at 9 weeks of age. Concentrations of testosterone and anti-GnRH antibodies in serum were determined by radioimmunoassay and enzyme immunoassay. The results showed that active immunization with MBP-GnRH6 increases the serum concentration of anti-GnRH antibodies (P<0.05) and decreased serum testosterone concentration (P<0.05) compared to MBP controls. At 25 weeks of age, the boars were sacrificed and the testes were evaluated histologically. Testis development was suppressed in MBP-GnRH6 immunized animals compared to MBP immunized boars. MBP-GnRH6 immunized pigs showed grasping behavior 4 weeks later than MBP immunized boars. No mature spermatozoa were observed in animals immunized with MBP-GnRH6. Quantitative real-time PCR analysis found that the amount of GnRHR mRNA in pituitary tissue was significantly lower in MBP-GnRH6-immunized animals than in controls (P<0.05). These data demonstrate that recombinant MBP-GnRH6 was effective in immunocastration of boars.
HSP65 serves as an immunogenic carrier for the diabetogenic peptide P277 that induces an anti-inflammatory immune response in NOD mice by nasal administration
Excerpt from the quote:
Epitope analysis showed that HSP65 proteins have numerous B and T cell epitopes, and HSP65 from Mycobacterium tuberculosis can induce a strong T cell-dependent immune response without the need for an external adjuvant when used as a carrier molecule linked to a peptide antigen [9 ]. We have used HSP65 as a carrier to develop cancer vaccines [10-13] and atherosclerosis vaccines [14,15]. However, HSP65 never serves as a carrier for P277-based vaccines.
Mucosal administration of the autoantigen HSP65 can induce an anti-inflammatory immune response and reduce organ-specific inflammation and disease in various models of autoimmunity, such as arthritis and atherosclerosis. We were interested in whether HSP65 can serve as an immunogenic carrier for the diabetogenic peptide P277 and also induce an anti-inflammatory immune response in NOD mice by mucosal administration. Thus, the dual functions of HSP65 and P277 against type 1 diabetes will be obtained. To test this hypothesis, we investigated the effect of intranasal vaccination with P277 tandem repeat sequences carried by HSP65 in the absence of adjuvant on autoimmune diabetes in NOD mice. We found a significant reduction in the incidence of diabetes, inhibition of insulitis, reduction in the secretion of isotype IgG2a antibodies against P277 and pro-inflammatory cytokines IFN-γ and IL-2, increase in subclass IgG1, IgG2b antibodies against P277 and anti-inflammatory cytokines IL-10 and IL-4 secretion, and reduced proliferation upon nasal application of the fusion protein HSP65-6×P277. Our results indicate that HSP65 may serve as a particularly beneficial carrier for P277-based vaccines, and mucosal delivery may represent a therapeutic approach for the treatment of type 1 diabetes.
A novel virus-like particle based on hepatitis B core antigen and the substrate-binding domain of the bacterial molecular chaperone DnaK
Excerpt from the quote:
After washing four times with TTBS, the protein bands were developed for several minutes at room temperature with TBS containing 3,3'-diaminobenzidine (DAB) and H 2 O 2 . Anti-GnRH antibody titers in immunized animals were detected by enzyme-linked immunosorbent assay (ELISA) as previously described . Briefly, 96-well flat bottom ELISA plates (Costar, USA) were coated with 100 μl/well of 0.1 mg/ml VEGF-GnRH fusion proteins in 0.1 mM carbonate-bicarbonate buffer and left overnight at 4 ° C held.
The core protein (HBc) of the hepatitis B virus has been shown to be an attractive carrier for foreign epitopes and can display green fluorescent protein (GFP) on its surface. The structure of the substrate binding domain of DnaK [DnaK (394-504 aa), DnaK SBD] is similar to GFP, so we reasoned that the DnaK SBD could also be tolerated. Electron microscopic observations suggest that chimeric proteins containing truncated HBc (HBcΔ) and the DnaK SBD could self-assemble into virus-like particles (VLPs). Subsequently, availability of DnaK SBD and adjuvantity of VLP HBcΔ-SBD were demonstrated using two recombinant peptide vaccines against gonadotropin-releasing hormone (GnRH), GhM and GhMNR. The latter additionally carries the NRLLLTG peptide motif known to bind to DnaK and the DnaK SBD. The combination of VLP HBcA-SBD and GhMNR elicited stronger humoral responses and caused further testicular atrophy than the combination of VLP HBcA and GhMNR or VLP HBcA-SBD and GhM in Balb/c mice. These findings indicate that VLP HBcA-SBD could serve as an excellent carrier for GhMNR and some other peptide vaccines.
Improved efficiency of DNA vaccination against prostate cancer by promoting a recombinant protein vaccine and introducing a new adjuvant epitope
Excerpt from the quote:
To enhance the anti-tumour effect of anti-GRP DNA vaccines, we used a Prime-Boost immunization strategy with anti-GRP DNA vaccines/HN protein. HSP65 has been used as a protein carrier and facilitated the immune response to conjugated vaccines in animals [11,15]. Several reports have reported that HSP65 appears to be an effective transfer protein in enhancing immunogenicity in the absence of Freund's adjuvant [10,11,16].
A DNA vaccine represents an attractive approach to cancer treatment by inducing active immunodeprivation of gastrin-releasing peptide (GRP) from tumor cells, whose growth depends on GRP stimulation. In this study, we developed a DNA vaccine using a plasmid vector to deliver the immunogen six copies of the B cell epitope GRP18–27 (display, andere).(GRP6). Multiple strategies have been employed to increase the potency of this DNA vaccine, including DNA prime protein boost immunization and introduction of a foreign T helper epitope into the DNA vaccine. Mice vaccinated with a DNA vaccine boosted with HSP65-GRP6 protein induced high titer and relatively high avidity of anti-GRP antibodies, as well as an inhibitory effect on prostate cancer growth in mice, superior to treatment with DNA alone or BCG with initial HSP65-GRP6 protein booster. In addition, the introduction of a new foreign T helper epitope into a GRP DNA vaccine demonstrated a significantly stronger humoral immune response against GRP and tumor rejection even than a DNA prime protein boost strategy. No further enhanced immunogenicity of this modified foreign T helper epitope DNA vaccine was observed even using the modified DNA vaccine priming strategy and the HSP65-GRP6 boost method. The data presented show that improving the potency of the anti-GRP DNA vaccine with the above two possible approaches should provide useful methods in the development of a new anti-growth factor DNA vaccine for cancer immunotherapy.
2022, Frontiers in immunology
Overexpression of Sirtuin Sirt3 protects neuronally differentiated PC12 cells from oxidative stress and trophic withdrawal-induced degeneration
Brain Research, Volume 1587, 2014, p. 40-53
Sirt3 is a mitochondrial sirtuin whose deacetylase activity regulates aspects of oxidative metabolic efficiency, antioxidant capacity and intramitochondrial signaling. In this study, we tested whether overexpression of the human Sirt3-myc transgene in differentiated PC12 cells, a model of sympathetic catecholaminergic neurons, would affect the susceptibility of these cells to oxidative stress or trophic withdrawal. Expression analysis revealed that the Sirt3-myc product is expressed as a 45 kDa proform, localized primarily in the cytosol, and as a 30 kDa processed form, primarily localized in mitochondria. When subjected to acute glucose deprivation or acute oxygen-glucose deprivation, differentiated PC12 cells overexpressing Sirt3-myc showed significantly lower levels of cytotoxicity, both at the end of injury and at various times after medium reperfusion, than cells transfected with a control plasmid. In addition, overexpression of Sirt3-myc also protected differentiated PC12 cells from apoptosis induced by trophic withdrawal. Together, these data demonstrate that upregulation of Sirt3 is sufficient to protect neuronal PC12 cells from cytotoxic insults, and add to the growing body of evidence that Sirt3 may be a target for neuroprotective intervention.
Homologous prime amplification based on intranasal administration of non-pathogenic invasive Escherichia coli expressing MPT64 reduces the spread of Mycobacterium tuberculosis
Cjepivo, volume 32, number 32, 2014, p. 4051-4058
Protein subunit vaccines as stimulatory strategies against tuberculosis (TB) infection are currently under investigation for tuberculosis vaccines. Their main limitation is their weak immunogenicity, making it necessary to combine protein subunits with auxiliary molecules. In this study, we used invasive replication-deficient drugsEscherichia colipressure to deliverMycobacterium tuberculoseof proteins in the cytoplasm of non-phagocytic eukaryotic cells using different initial and primary vaccination protocols. Our results show that intranasal administration is invasiveE coliexpressionM. tuberculoseof the protective antigen MPT64 to mice administered a recombinant BCG strain overexpressing MPT64 on the surface reduces the bacterial load in the spleen of the mouse. Our data suggest that the replication deficiency is invasiveE colimay be a suitable platform for BCG/rBCG priming followed by homologous immunization strategies.
α1A-adrenergic receptor antagonism improves erectile and cavernous responses in rats with cavernous nerve damage and enhances neurogenic responses in the human corpus cavernosum in patients with erectile dysfunction secondary to radical prostatectomy
Journal of Sexual Medicine, Volume 13, Issue 12, 2016, p. 1844-1857
Cavernous nerve injury (CNI) in rats and radical prostatectomy (RP) in men result in loss of nitrergic function and increased adrenergic neurogenic contractions of the cavernous tissue.
To evaluate the modulation of the α-adrenergic system as a strategy to alleviate erectile dysfunction (ED) and functional cavernous changes caused by CKD.
Non-selective α-blocker (phentolamine 1 mg/kg per day), selective α-blocker1Ablocker (silodosin [SILOD] 0.1 mg/kg daily), or vehicle was administered orally for 4 weeks after bilateral crush CNI (BCNI). Erectile and neurogenic responses of the corpus cavernosum (CC) were assessed. The acute effects of SILOD were also assessed in vivo (0.03 mg/kg intravenously) and ex vivo (10 nmol/L). The effects of SILOD and tadalafil (TAD) on nitrergic relaxations were assessed in human CC from patients with ED of vascular etiology or ED secondary to RP.
Erectile responses in vivo in the rat and neurogenic contractions and relaxations of the rat and human CC.
Long-term treatment with SILOD significantly improved erectile response and enhanced erectile response by acute treatment with TAD (0.3 mg/kg intravenously) in rats with BCNI. SILOD partially restored nitrergic relaxations and normalized neurogenic contractions in CC of rats with BCNI. Long-term treatment with SILOD partially prevented BCNI-induced down-regulation of nitric oxide synthase expression. Acute administration of SILOD (0.03 mg/kg intravenously) improved erectile responses in vivo and increased nitrergic relaxation and decreased neurogenic contractions ex vivo in the CC of BCNI rats. In human CC from patients with ED of vascular etiology, TAD (30 nmol/L), SILOD (10 nmol/L) or their combination increased nitrergic relaxations. Potentiation by TAD was lost in human CC of ED patients after RP, but was restored after concomitant treatment with SILOD.
α-adrenergic modulation, especially selective α1Ablockade, improves erectile and cavernous functions after BCNI. Modulation of the adrenergic system, mainly in combination strategies, could play a role in the treatment of ED after RP.
Surgical immunological interventions for solid malignancies
The American Journal of Surgery, pagina 212, broj 4, 2016., str. 682-690.e5
The aim of this study was to systematically assess regionally delivered clinically translatable immunotherapeutic agents for solid malignancies.
PubMed IClinicalTrials.govpublished or registered clinical studies were searched. The search yielded 334 relevant publications, of which 116 articles were included in the review after application of the exclusion criteria.
Over the past 5 years, there has been an increase in the regional administration of cell-based and viral vector-based clinical trials. Surgical interventions for intrapleural, intracranial, intraperitoneal, and intratumoral access routes have been developed to improve the local delivery of these therapies. Multimodal therapies that combine regional immunotherapy with other local and systemic therapies are showing steady growth as the field of immunotherapy continues to expand.
Inflammatory models dramatically alter tumor growth and the immune microenvironment in hepatocellular carcinoma
Scientific Bulletin, Volume 60, Issue 8, 2015, p. 762-772
The onset and progression of hepatocellular carcinoma (HCC) is closely related to chronically diseased liver tissue. This background of diseased liver tissue is a drastically different microenvironment than a healthy liver, especially with regard to the prevalence of immune cells and the presence of mediators of immune function. To better understand the consequences of liver disease on tumor growth and interaction with its microenvironment, we used two standard methods of fibrosis induction and orthotopic tumor implantation in inflamed and fibrotic liver to mimic the liver disease of HCC patients. Compared to non-diseased controls, tumor growth was significantly improved under fibrotic conditions. The tumor-infiltrating immune cells were also drastically different, with fewer natural killer cells but significantly more immunosuppressive CD11b+Gr1bokof myeloid cells in both models of fibrosis. In addition, there were model-specific differences: increased CD11b counts+the myeloid cell a CD4+CD25+T cells were found in tumors in the bile duct ligation model but not in the tetrachloride model. The induction of fibrosis altered the cytokine production of implanted tumor cells, which could have far-reaching implications for the immune infiltrate and its functionality. Taken together, this work demonstrates that the combination of fibrosis induction with orthotopic tumor implantation results in markedly different tumor microenvironment and tumor growth kinetics, highlighting the need for more accurate modeling of HCC progression in mice that accounts for the drastic tissue changes caused due to chronic liver disease.
A bioluminescent transgenic mouse model: in vivo imaging of antioxidant EC-SOD gene expression in real time and regulation by gamma interferon
Gene, Volume 530, Number 1, 2013, p. 75-82
Extracellular superoxide dismutase (EC-SOD) is the major antioxidant enzyme in the extracellular matrix. We have developed transgenic mice to analyze EC-SOD promoter activity in vivo in real time and to identify key cis elements around the 5' region of the mouse EC-SOD gene. Using this model, we have shown that luciferase reporter activity closely correlates with endogenous EC-SOD expression, although several interesting differences were also observed. Specifically, luciferase activity was detected at the highest levels in the testis, aorta and perirenal fat. Reporter expression was regulated by interferon gamma, a finding consistent with published studies of endogenous EC-SOD gene expression. Therefore, the 5' flanking region of the mouse EC-SOD gene is responsible, at least in part, for cell-specific and inducible expression.
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