Cancer immunotherapy is an approach to cancer therapy that involves the enhancement of the cancer patient’s own innate and/or adaptive immune systems to attack their own cancer. Clinically available cancer immunotherapies rely on different strategies: infusion of ex vivo manipulated autologous dendritic cells (DCs), infusion of genetically engineered autologous cytotoxic CD8+ T lymphocytes, stimulation of T lymphocyte proliferation, or inhibition of immunosuppressive pathways to improve T lymphocyte effector function. Nonetheless, only a small percentage of cancer patients receive benefit from immunotherapies and thus further improvements in clinical outcomes are required. Among numerous other therapeutic immunotherapies strategies being developed and tested, adenovirus serotype 5-based vectors (Ad5) have been well studied in preclinical and clinical settings. Preclinical research has shown that vaccination of mice with Ad5-OVA (an Ad5 encoding a model tumor antigen, chicken ovalbumin (OVA)) results in activation and proliferation of OVA-specific CD8+ T lymphocytes capable of specific killing of tumor cells that express OVA. This dissertation evaluates the potential of polymeric nanoparticles (NP) loaded with all-trans retinoic acid (ATRA), a vitamin A derivative with potent immunostimulatory effects, to improve the immunostimulatory and therapeutic effects of Ad5-OVA in a murine E.G7-OVA tumor model, a well described model that can be used for studying the immune response to Ad5-based immunotherapies. In the first part of this work, poly(lactide-co-glycolide) NP loaded with ATRA (ATRA-PLGA-NP) were prepared and characterized. Next, the antitumor effect and the magnitude of the OVA-specific immune response due to Ad5-OVA vaccination versus ATRA-PLGA-NP (or ATRA soluble) plus Ad5-OVA combination treatment were compared in vivo. The results showed that the combination treatment using ATRA-NP, but not ATRA soluble, resulted in enhanced survival and enhanced levels of OVA-specific CD8+ T lymphocytes in peripheral blood, spleen, and tumor. Next, cRGD- and mannose-functionalized PLGA-PEG NP were developed in an attempt to actively target the tumor neovasculature and DC-rich organs, respectively. The functionalization efficacy was confirmed by ex vivo fluorescence imaging studies. In vivo studies using E.G7-OVA-challenged mice showed that treatment with ATRA-loaded cRGD-functionalized PLGA-PEG-NP + Ad5-OVA, despite not enhancing the levels of OVA-CD8+ T lymphocytes in peripheral blood, substantially enhanced survival compared to either the combination of Ad5-OVA + non-functionalized ATRA-PLGA-PEG-NP or Ad5-OVA + conventional ATRA-PLGA-NP. On the contrary, treatment with mannose-functionalized PLGA-PEG-NP + Ad5-OVA, despite optimally enhancing the levels of OVA-CD8+ T lymphocytes in peripheral blood (compared to all other treatment groups), did not lead to enhanced survival compared to either the combination of Ad5-OVA + non-functionalized ATRA-PLGA-PEG-NP, Ad5-OVA + conventional ATRA-PLGA-NP, and over Ad5-OVA treatment alone. Although not investigated further in this dissertation, it was speculated that the observed trend in survival benefit provided by ATRA-PLGA-PEG-cRGD-NP + Ad5-OVA over the other NP formulations may have been due to higher levels of ATRA within the TME due to actively targeting the tumor vasculature, corroborating previous studies which demonstrated that ATRA functions as a potent stimulator of anti-tumor cellular immune responses within the tumor. The paradoxical results obtained with mannose-functionalized PLGA-PEG-NP are less readily explained. In conclusion, it was demonstrated in this work that the co-administration of Ad5-OVA and ATRA-loaded NP formulations enhanced the tumor specific cellular immune response and the survival of tumor challenged mice compared to vaccination with Ad5-OVA alone.

名古屋大学博士学位論文 学位の種類:博士（医療技術学） (課程) 学位授与年月日　平成22年3月25日

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The commonly used PLGA-based delivery systems are often limited by their inadequate drug loading and release properties. This study reports the integration of oil into PLGA to form the prototype of a hybrid drug carrier PONC. Our primary goal is to confer the key strength of lipid-based drug carriers, i.e. efficient encapsulation of lipophilic compounds, to a PLGA system without taking away its various useful qualities. The PONC were formulated by emulsification solvent evaporation technique, which were then characterized for particle size, encapsulation efficiency, drug release and anticancer efficacy. The ATRA loaded PONC showed excellent encapsulation efficiency and release kinetics. Even after surface functionalization with PEG , controlled drug release kinetics was maintained, with 88.5% of the encapsulated ATRA released from the PEG-PONC in a uniform manner over 120 hours. It also showed favorable physicochemical properties and serum stability. PEG-PONC has demonstrated substantially superior activity over the free ATRA in ovarian cancer cells that are non-responsive to the standard chemotherapy. The newly developed PEG-PONC significantly reduced the IC50 values (p<0.05) in the chemoresistant cells in both MTT and colony formation assays. Hence, this new ATRA-nanoformulation may offer promising means for the delivery of lipophilic compounds like all-trans retinoic acid to treat highly resistant ovarian cancer. / Pharmaceutical Sciences

Macrophages can be activated by a variety of extracellular signals to polarize to either the M1 (inflammatory and antimicrobial) or to the M2 (wound repair and inflammation resolution) phenotype. Expression of arginase 1 in macrophages is a key marker of the M2 phenotype. Arginase 1 expression is induced by interleukin 4 (IL-4), a cytokine secreted by Th2 helper cells. All-trans retinoic acid (ATRA) is a product of metabolism of dietary retinol (vitamin A). In a manner analogous to hormones, ATRA binds to nuclear receptors in cells and influences gene expression and cell physiology. ATRA is important in the resolution of inflammation systemically and on the cellular level, however it has not been linked to M2 activation or arginase 1 expression. Testing the hypothesis that ATRA can induce arginase 1 in macrophages either directly or indirectly, it was found that ATRA alone cannot cause murine bone marrow-derived macrophages (BMDM) to activate in the M2 phenotype (as indicated by arginase 1 expression), however it can dramatically potentiate induction of arginase 1 expression and activity by IL-4. This is the first observation positively linking ATRA to arginase 1. Lipopolysaccharide (LPS), is a conserved structural component of the outer membrane of Gram negative bacteria, and a potent pyrogen. In metabolic endotoxemia, LPS concentration in the blood is slightly elevated, and over the long term this contributes to diverse inflammatory diseases such as atherosclerosis, obesity, and diabetes. LPS promotes the M1 phenotype and suppresses the M2 phenotype, but its contribution at low doses such as those found in metabolic endotoxemia are not well studied. In order to investigate mechanisms of LPS suppression at low doses, mice deficient in IRAK1 and tollip, key mediators or proinflammatory LPS signaling, were used to study IL-4, ATRA, and LPS crosstalk. LPS suppression of arginase 1 was found to be dependent on IRAK1 and tollip, but only at low doses of LPS. / Ph. D.

Systemic lupus erythematosus (SLE) is an autoimmune disease involving the inflammatory damages of multiple organs. Lupus nephritis (LN) as the manifestation in the kidney occurs in more than 50% of SLE patients and is a major cause of morbidity and mortality. Current treatments consist of immunosuppressants that always lead to compromised immune responses with increased risks of infections as the major side effect. To minimize this side effect, it is crucial to develop new treatments that are more natural and specific. Vitamin A, particularly in the form of its functional metabolite, retinoic acid, has shown some beneficial effects against LN in both lupus-prone mouse models and clinical cases. However, a more systemic evaluation of vitamin A treatment in lupus had not been investigated. In our study, we found paradoxical effects of all-trans-retinoic acid (tRA) on lupus-like disease in MRL/lpr lupus-prone mice. Starting at 6 weeks old when the inflammatory environment had been established in MRL/lpr mice, tRA administration reduced immune cell numbers in the secondary lymphoid organs and improved glomerulonephritis. However, circulating autoantibodies and inflammation in renal tubulointerstitium and other organs were increased. The detrimental effects of tRA were not present in MRL control mice, which didn't have an established inflammatory environment at 6 weeks old as shown in MRL/lpr mice, suggesting that the pro-inflammatory effects of tRA are dependent on the pre-existing inflammatory environment. Therefore, to successfully apply vitamin A-based treatment, it is important to avoid the detrimental effects of tRA on lupus by identifying and then specifically eliminating the critical pro-inflammatory immune cell types in lupus. As treatments usually start after the onset of apparent symptoms in patients at the effector stage of autoimmune responses, targeting the inflammatory contributors at this stage appears to be more practical and critical. Among different types of leukocytes, we chose to focus on dendritic cells (DCs), because they are highly diverse and critical in the immune responses as a bridge between the innate and adaptive immune systems. Plasmacytoid DCs (pDCs) as a candidate target have been demonstrated to be crucial for the initiation of lupus development by producing IFNα. However, we demonstrated that although pDCs produced a large amount of IFNα during disease initiation, those from late-stage lupus mice were found to be defective in producing IFNα, suggesting that pDC-targeted treatments should be performed at the initiation stage. This will depend on the progress in early diagnosis in the future. Besides pDCs, we identified a CD11c+ cell population absent at the early-stage but gradually accumulating at the late-stage in the kidneys of lupus mice. These cells have a phenotype of mature monocyte-derived DCs, with particularly high CX3CR1 expression on the surface. Consistent with their pathogenic cytokine profile, in vivo administration of anti-CX3CR1-saporin conjugates to dysfunction these cells in MRL/lpr mice significantly reduced proteinuria scores. Ex vivo activation of renal-infiltrating CD4+ T cells showed increased survival rate, proliferation and IFN-γ production of activated CD4+ T cells when they were cultured with these renal-infiltrating CD11c+ cells. These results suggest that the renal-infiltrating CD11c+ cells are pathogenic and promote inflammation in the kidney at the later effector stage of lupus by interacting with renal-infiltrating CD4+ T cells. In conclusion, although vitamin A showed anti-inflammatory effects on reducing glomerulonephritis, its use in lupus treatment should be guarded due to the other potential pro-inflammatory effects induced by the pre-existing inflammatory environment. IFNα-producing pDCs and CX3CR1highCD11c+ monocyte-derived DCs could be specific therapeutic targets to reduce the established inflammation at the early stage and late stage of LN, respectively. Therefore, it is worthwhile to further investigate the comprehensive effects of combination therapy on lupus, with vitamin A administration and pDCs-specific depletion at the early stage, and CX3CR1highCD11c+ monocyte-derived DCs-specific depletion at the late stage. / Ph. D.

Oxidative stress plays a vital role in the pathogenesis of many chronic and acute inflammatory diseases. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are two key mediators that are known to induce cellular and tissue oxidative stress. The generation of ROS and RNS is mediated by innate immune signaling processes. Lipopolysaccharide (LPS), a major inflammatory signal, is known to be a potent inducer of ROS/RNS. Thus, strategies that may block LPS-mediated generation of free radicals may hold promise in treating various inflammatory disease processes. However, the molecular mechanisms underlying LPS-mediated ROS/RNS production are not fully defined. Interleukin-1 Receptor associated kinase (IRAK-1), an intracellular kinase downstream of Toll-like Receptor 4 (TLR4) has been shown to contribute to the inflammatory cascade associated with LPS-TLR4 signaling pathway. However, its role in ROS production has not been defined. Therefore, we tested the hypothesis that IRAK-1 plays an important role in regulating ROS/RNS production. Both in vitro and in vivo studies were conducted to investigate the role of IRAK-1 in modulating free radicals as well as oxidative stress. In vitro studies demonstrate that IRAK-1 is a critical molecule involved in the induction of ROS/RNS. IRAK-1 deletion ablated free radical production following LPS challenge in a variety of cell types including macrophages, fibroblasts and microglia. Mechanistically, we observed that IRAK-1 is required for optimal expression and activity of NADPH oxidase subunits and iNOS. IRAK-1 deletion reduced LPS-triggered p47phox membrane translocation, suppressed NOX-1 expression and protein levels as well as hampered Rac1 activation. On the other hand, IRAK-1 deletion sustained antioxidative enzyme activity and levels in IRAK-1-/- macrophages and fibroblasts. In terms of the in vivo physiological consequences, IRAK-1-/- mice exhibited attenuated lipid peroxidation in vital organs, attenuated histopathological lesions in liver and kidney, and reduced endotoxemia-associated mortality. Taken together, IRAK-1 may, at least in part, serve as an important therapeutic target in the treatment of various inflammatory disease processes. / Ph. D.

Chemotherapy is one of the most important treatments for cancer. However, systemic toxicity, drug resistance and unstable kinetics of the drug in the blood are serious problems of chemotherapy. The use of biodegradable polymers for controlled release of anticancer drugs has gained popularity in recent years. Controlled release of drugs from polymeric carriers has some advantages such as improvement in the efficiency of treatment, reduction in systemic toxicity and prevention of the drug resistance that is developed by the cancer cells. In this study, poly(D,L-lactide-co-glycolide) microparticles were used as carriers for the controlled release of all-trans-Retinoic acid, tamoxifen, tamoxifen citrate and idarubicin. It was aimed to prepare a drug carrier system for controlled release of hydrophobic anticancer drugs. The empty and drug loaded poly (D,L-lactide-co-glycolide) microparticles were prepared by solvent extraction/evaporation technique with single emulsion (oil/water). Optimized microparticles were characterized by using inverted light microscopy and scanning electron microscopy to examine their morphology and sizes. Drug content of microparticles and the amount of released drug were determined spectrophotometrically. In vitro toxicity of the microparticles on MCF-7 human breast cancer cells was investigated. It was revealed that the microparticles were smooth and spherical in shape. Their sizes differed in the range of 2-20 &micro / m. atRA-loaded microparticles showed approximately 90% encapsulation efficiency and it was confirmed that changing in drug/polymer ratio affected the extend of drug content. Increase in drug content caused a slower release pattern. Moreover, although the empty microparticles caused some toxicity, atRA-loaded PLGA microparticles showed slight cell growth inhibition.

Submitted by Camila Girondi (camila.girondi@gmail.com) on 2018-07-03T20:30:17Z No. of bitstreams: 1 Dissertação 28.06 COM FICHA CATALOGRÀFICA.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-07-10T19:06:46Z (GMT) No. of bitstreams: 1 girondi_cm_me_sjc.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) / Made available in DSpace on 2018-07-10T19:06:46Z (GMT). No. of bitstreams: 1 girondi_cm_me_sjc.pdf: 1652288 bytes, checksum: 2ff0f9722f6563cc30aaacbdd2bd4b81 (MD5) Previous issue date: 2018-05-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As nanofibras (NF) podem ser sintetizadas por meio de eletrofiação, um método simples que permite incorporação de fármacos em biopolímeros que apresentam a vantagem de serem liberados de forma gradual. Policaprolactona (PCL) apresenta a vantagem de poder ser eletrofiada permitindo a incorporação de fármacos. Os ácidos retinoicos são fármacos empregados no tratamento de osteossarcoma, mas, apresentam efeitos colaterais. O ATRA (all-trans-retinoic-acid) é o mais comum entre os retinoides. Os objetivos deste estudo foram: sintetizar e caracterizar NF, incorporar o fármaco a elas e verificar a liberação ao meio de cultura; realizar testes de citoxicidade e genotoxicidade tais como: crescimento, integridade, viabilidade e micronúcleo de células MG63 tratadas com NF incorporada com ATRA e analisar a secreção das citocinas pró inflamatórias: IL-1β, IL-6 e TNF-α por meio do teste ELISA. As NF sintetizadas por meio da eletrofiação foram caracterizadas morfologicamente e bioquimicamente por meio de microscopia eletrônica de varredura (MEV) e estudo do espectro de infravermelho da transformada de Fourrier (FTIR): Os testes in vitro foram realizados utilizando uma linhagem de células imortalizadas de osteossarcoma, MG63. Os ensaios incluídos nesse estudo foram divididos em grupos compostos por: [C (controle puro), ATRA (controle positivo), NF (controle negativo) e NF + ATRA (grupo experimental).] Em todos os grupos foram realizados testes de viabilidade celular (MTT), micronúcleo e ELISA sob os tempos de 3, 7 e 14 dias. A liberação do fármaco através do sistema de NF+ATRA foi comprovada pelo FTIR. Os demais resultados encontrados foram avaliados através do teste ANOVA one-way, no qual o método apresentou-se eficiente, mostrando diferença estatística de p=0,00, sendo signficante para todos os períodos de tempo nos testes de MTT e MN, além de ser verificada a secreção de citocinas proinflamatórias IL-1β e IL-6, comprovando os efeitos citotóxicos e genotoxicos sob células MG63 mostrando a efetividade da técnica. Podendo ser uma alternativa para o tratamento. / Nanofibers (NF) can be synthesized by electro-spinning, a simple method that allows incorporation of drugs into biopolymers that have the advantage of being released gradually. Polycaprolactone (PCL) has the advantage that it can be electrophied allowing the incorporation of drugs. Retinoic acids are drugs used in the treatment of osteosarcoma, but have side effects. ATRA (all-trans-retinoicacid) is the most common retinoid. The objectives of this study were: to synthesize and characterize NF, to incorporate the drug to them and to verify the release to the culture medium; perform cytotoxicity and genotoxicity tests such as: growth, integrity, viability and micronucleus of N63-treated NF-treated cells with ATRA and to analyze the secretion of pro-inflammatory cytokines: IL-1β, IL-6 and TNFα by the ELISA . The NF synthesized by electrophilation were characterized morphologically and biochemically by scanning electron microscopy (SEM) and Fourrier Transform Infrared Spectrum (FTIR) study: In vitro tests were performed using an immortalized osteosarcoma cell line, MG63. The trials included in this study were divided into groups composed of: C (pure control), ATRA (positive control), NF (negative control) and NF + ATRA (experimental group). All groups were tested for cell viability (MTT), micronucleus and ELISA under the times of 3, 7 and 14 days. Release of the drug through the NF + ATRA system was confirmed by FTIR. The other results were evaluated using the oneway ANOVA test, in which the method was efficient, showing a statistical difference of p = 0.00, being significant for all time periods in the MTT and MN tests, besides the secretion of proinflammatory cytokines IL-1β and IL-6, proving the cytotoxic and genotoxic effects under MG63 cells, showing the effectiveness of the technique. It may be an alternative to treatment

All-trans retinoic acid (atRA) mediated growth inhibition results in the arrest of the cell cycle during the G1 phase in CAOV3 cells but not SKOV3 ovarian carcinoma cells. The G1 checkpoint is regulated by a multitude of molecules such as the retinoblastoma family of proteins, cyclins, cyclin dependent kinases (CDKs) and cyclin dependent kinase inhibitors (CDKis). CAOV3 cells, which are atRA sensitive, have been shown to express p16INK4a (p16), a cyclin dependent kinase inhibitor regulating the G1 checkpoint. However, atRA resistant SKOV3 cells do not express p16. In these studies, we investigated the role of p16 in mediating atRA induced growth arrest. Our results show that overexpression of p16 in SKOV3 cells leads to growth inhibition following atRA treatment. However, the inhibition is short-term due to the loss of p16 expression. Nevertheless, these results show that p16 plays a role in atRA mediated growth inhibition in ovarian carcinoma cells and that modulation of p16 expression can determine the growth response to atRA. Additionally, we also examined the effect of atRA treatment on the expression of homeobox genes in the CAOV3 cells and SKOV3 cells model system. Homeobox genes comprise a family of transcription factors which function during embryonic development to control pattern formation, differentiation and proliferation. Besides their dominant role during embryogenesis, they are also expressed in adults. In human tumors, an association between the deregulation of the expression of homeobox genes and oncogenic transformation has been reported. It is known that some homeobox genes are atRA targets due to the presence of retinoic acid response element (RARE) either in their promoter region or in their 3' region. In these studies we examined the expression of 13 homeobox genes in CAOV3 cells and SKOV3 cells following ethanol or atRA treatment. The 13 homeobox genes were analyzed because previous studies done by our laboratory observed differences in expression of these homeobox genes when comparing atRA sensitive oral squamous carcinoma cells (SCC) to atRA resistant oral squamous cell carcinoma cells. Of the 13 homeobox genes analyzed in the ovarian carcinoma cell model system, we found HOXA1 and HOXB4 to be upregulated by atRA in CAOV3 cells but not in SKOV3 cells. We also found that the induction of HOXA1 and HOXB4 mRNA expression in CAOV3 cells occurred as a respond to atRA treatment and is not due to a generalized response because of overall growth reduction. Interestingly, HOXA1 has two alternatively spliced forms. The mRNA expression of the truncated form of HOXA1 is highly induced by atRA when compared to its full length form. HOXB1, which is HOXA1 target gene, was not upregulated following atRA treatment. These results suggest that: 1) expression of p16 plays a role in mediating atRA growth inhibition; 2) HOXA1 and HOXB4 also play a role in mediating growth suppression by atRA; and 3) the truncated form of HOXA1 is induced by atRA treatment and may play a role in mediating growth inhibition by atRA, perhaps by acting in a dominant negative fashion. / Microbiology and Immunology