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1.
J Transl Med ; 19(1): 526, 2021 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-34952611

RESUMO

The host's immune system may be primed against antigens during the lifetime (e.g. microorganisms antigens-MoAs), and swiftly recalled upon growth of a tumor expressing antigens similar in sequence and structure. C57BL/6 mice were immunized in a preventive setting with tumor antigens (TuAs) or corresponding heteroclitic peptides specific for TC-1 and B16 cell lines. Immediately or 2-months after the end of the vaccination protocol, animals were implanted with cell lines. The specific anti-vaccine immune response as well as tumor growth were regularly evaluated for 2 months post-implantation. The preventive vaccination with TuA or their heteroclitic peptides (hPep) was able to delay (B16) or completely suppress (TC-1) tumor growth when cancer cells were implanted immediately after the end of the vaccination. More importantly, TC-1 tumor growth was significantly delayed, and suppressed in 6/8 animals, also when cells were implanted 2-months after the end of the vaccination. The vaccine-specific T cell response provided a strong immune correlate to the pattern of tumor growth. A preventive immunization with heteroclitic peptides resembling a TuA is able to strongly delay or even suppress tumor growth in a mouse model. More importantly, the same effect is observed also when tumor cells are implanted 2 months after the end of vaccination, which corresponds to 8 - 10 years in human life. The observed potent tumor control indicates that a memory T cell immunity elicited during the lifetime by a antigens similar to a TuA, i.e. viral antigens, may ultimately represent a great advantage for cancer patients and may lead to a novel preventive anti-cancer vaccine strategy.


Assuntos
Vacinas Anticâncer , Células T de Memória , Animais , Antígenos de Neoplasias , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Peptídeos
2.
Biogerontology ; 21(5): 559-575, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32189112

RESUMO

Human HSP27 is a small heat shock protein that modulates the ability of cells to respond to heat shock and oxidative stress, and also functions as a chaperone independent of ATP, participating in the proteasomal degradation of proteins. The expression of HSP27 is associated with survival in mammalian cells. In cancer cells, it confers resistance to chemotherapy; in neurons, HSP27 has a positive effect on neuronal viability in models of Alzheimer's and Parkinson's diseases. To better understand the mechanism by which HSP27 expression contributes to cell survival, we expressed human HSP27 in the budding yeast Saccharomyces cerevisiae under control of different mutant TEF promoters, that conferred nine levels of graded basal expression, and showed that replicative lifespan and proteasomal activity increase as well as the resistance to oxidative and thermal stresses. The profile of these phenotypes display a dose-response effect characteristic of hormesis, an adaptive phenomenon that is observed when cells are exposed to increasing amounts of stress or toxic substances. The hormetic response correlates with changes in expression levels of HSP27 and also with its oligomeric states when correlated to survival assays. Our results indicate that fine tuning of HSP27 concentration could be used as a strategy for cancer therapy, and also for improving neuronal survival in neurodegenerative diseases.


Assuntos
Proteínas de Choque Térmico HSP27 , Hormese , Saccharomyces cerevisiae , Animais , Proteínas de Choque Térmico HSP27/metabolismo , Proteínas de Choque Térmico , Resposta ao Choque Térmico , Humanos , Chaperonas Moleculares , Estresse Oxidativo , Saccharomyces cerevisiae/metabolismo
3.
J Transl Med ; 16(1): 286, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340600

RESUMO

BACKGROUND: A novel prediction algorithm is needed for the identification of effective tumor associated mutated neoantigens. Only those with no homology to self wild type antigens are true predicted neoantigens (TPNAs) and can elicit an antitumor T cell response, not attenuated by central tolerance. To this aim, the mutational landscape was evaluated in HCV-associated hepatocellular carcinoma. METHODS: Liver tumor biopsies and adjacent non-tumor liver tissues were obtained from 9 HCV-chronically infected subjects and subjected to RNA-Seq analysis. Mutant peptides were derived from single nucleotide variations and TPNAs were predicted using two prediction servers (e.g. NetTepi and NetMHCstabpan) by comparison with corresponding wild-type sequences, non-related self and pathogen-related antigens. Immunological confirmation was obtained in preclinical as well as clinical setting. RESULTS: The development of such an improved algorithm resulted in a handful of TPNAs despite the large number of predicted neoantigens. Furthermore, TPNAs may share homology to pathogen's antigens and be targeted by a pre-existing T cell immunity. Cross-reactivity between such antigens was confirmed in an experimental pre-clinical setting. Finally, TPNAs homologous to pathogen's antigens were found in the only HCC long-term survival patient, suggesting a correlation between the pre-existing T cell immunity specific for these TPNAs and the favourable clinical outcome. CONCLUSIONS: The new algorithm allowed the identification of the very few TPNAs in cancer cells, and those targeted by a pre-existing immunity strongly correlated with long-term survival. Only such TPNAs represent the optimal candidates for immunotherapy strategies.


Assuntos
Antígenos de Neoplasias/imunologia , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Idoso , Sequência de Aminoácidos , Animais , Sítios de Ligação , Sobreviventes de Câncer , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Linhagem Celular , Simulação por Computador , Modelos Animais de Doenças , Epitopos/metabolismo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Hepacivirus/fisiologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Imunidade , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Camundongos Endogâmicos C57BL , Mutação/genética , Reprodutibilidade dos Testes , Homologia de Sequência de Aminoácidos , Microambiente Tumoral/imunologia
4.
J Transl Med ; 14: 58, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26911136

RESUMO

BACKGROUND: The tumor immunosuppressive microenvironment represents a major obstacle to an effective tumor-specific cellular immune response. METHODS: In the present study, the counterbalance effect of a novel metronomic chemotherapy protocol on such an immunosuppressive microenvironment was evaluated in a mouse model upon sub-cutaneous ectopic implantation of B16 melanoma cells. The chemotherapy consisted of a novel multi-drug cocktail including taxanes and alkylating agents, administered in a daily metronomic fashion. The newly designed strategy was shown to be safe, well tolerated and significantly efficacious. RESULTS: Treated animals showed a remarkable delay in tumor growth and prolonged survival as compared to control group. Such an effect was directly correlated with CD4(+) T cell reduction and CD8(+) T cell increase. Furthermore, a significant reduction in the percentage of both CD25(+)FoxP3(+) and CD25(+)CD127(low) regulatory T cell population was found both in the spleens and in the tumor lesions. Finally, the metronomic chemotherapy induced an intrinsic CD8(+) T cell response specific to B16 naturally expressed Trp2 TAA. CONCLUSION: The novel multi-drug daily metronomic chemotherapy evaluated in the present study was very effective in counterbalancing the immunosuppressive tumor microenvironment. Consequently, the intrinsic anti-tumor T cell immunity could exert its function, targeting specific TAA and significantly containing tumor growth. Overall, the results show that this represents a promising adjuvant approach to significantly enhance efficacy of intrinsic or vaccine-elicited tumor-specific cellular immunity.


Assuntos
Administração Metronômica , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melanoma Experimental/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Calreticulina/metabolismo , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , ELISPOT , Feminino , Interferon gama/biossíntese , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Análise de Sobrevida , Linfócitos T Reguladores/efeitos dos fármacos
5.
BMC Microbiol ; 16(1): 111, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27316672

RESUMO

BACKGROUND: A large collection of sequenced mycobacteriophages capable of infecting a single host strain of Mycobacterium smegmatis shows considerable genomic diversity with dozens of distinctive types (clusters) and extensive variation within those sharing evident nucleotide sequence similarity. Here we profiled the mycobacterial components of a large composting system at the São Paulo zoo. RESULTS: We isolated and sequenced eight mycobacteriophages using Mycobacterium smegmatis mc(2)155 as a host. None of these eight phages infected any of mycobacterial strains isolated from the same materials. The phage isolates span considerable genomic diversity, including two phages (Barriga, Nhonho) related to Subcluster A1 phages, two Cluster B phages (Pops, Subcluster B1; Godines, Subcluster B2), three Subcluster F1 phages (Florinda, Girafales, and Quico), and Madruga, a relative of phage Patience with which it constitutes the new Cluster U. Interestingly, the two Subcluster A1 phages and the three Subcluster F1 phages have genomic relationships indicating relatively recent evolution within a geographically isolated niche in the composting system. CONCLUSIONS: We predict that composting systems such as those used to obtain these mycobacteriophages will be a rich source for the isolation of additional phages that will expand our view of bacteriophage diversity and evolution.


Assuntos
Micobacteriófagos/genética , Micobacteriófagos/isolamento & purificação , Mycobacterium/genética , Mycobacterium/virologia , Microbiologia do Solo , Solo , Bacteriófagos/genética , Sequência de Bases , Brasil , DNA Bacteriano/genética , DNA Viral/genética , Evolução Molecular , Genes Bacterianos , Variação Genética , Genoma Viral , Família Multigênica , Micobacteriófagos/classificação , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Mycobacterium smegmatis/classificação , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/isolamento & purificação , Mycobacterium smegmatis/virologia , Filogenia
6.
Cancer Immunol Immunother ; 64(10): 1305-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25944003

RESUMO

Hepatocellular carcinoma (HCC) is the most frequent primary liver cancer and represents the third and the fifth leading cause of cancer-related death worldwide in men and women, respectively. Hepatitis B virus (HBV) and hepatitis C virus (HCV) chronic infections account for pathogenesis of more than 80 % of primary HCC. HCC prognosis greatly varies according to stage at beginning of treatment, but the overall 5-year survival rate is approximately 5-6 %. Given the limited number of effective therapeutic strategies available, immunotherapies and therapeutic cancer vaccines may help in improving the clinical outcome for HCC patients. However, the few clinical trials conducted to date have shown contrasting results, indicating the need for improvements. In the present study, a novel combinatorial strategy, based on metronomic chemotherapy plus vaccine, is evaluated in a mouse model. The chemotherapy is a multi-drug cocktail including taxanes and alkylating agents, which is administered in a metronomic-like fashion. The vaccine is a multi-peptide cocktail including HCV as well as universal tumor antigen TERT epitopes. The combinatorial strategy designed and evaluated in the present study induces an enhanced specific T cell response, when compared to vaccine alone, which correlates to a reduced Treg frequency. Such results are highly promising and may pave way to relevant improvements in immunotherapeutic strategies for HCC and beyond.


Assuntos
Administração Metronômica , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacinas Anticâncer/administração & dosagem , Carcinoma Hepatocelular/terapia , Hepacivirus/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Hepatite C/imunologia , Neoplasias Hepáticas/terapia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Alquilantes/uso terapêutico , Animais , Antígenos Virais/imunologia , Carcinoma Hepatocelular/etiologia , Carcinoma Hepatocelular/imunologia , Células Cultivadas , Terapia Combinada , Modelos Animais de Doenças , Feminino , Hepatite B/complicações , Hepatite C/complicações , Humanos , Epitopos Imunodominantes/metabolismo , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/imunologia , Ativação Linfocitária , Masculino , Camundongos Endogâmicos C57BL , Taxoides/uso terapêutico , Telomerase/imunologia , Telomerase/metabolismo
7.
J Immunol ; 190(5): 2391-402, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23355734

RESUMO

The antitumor activity of LPS was first described by Dr. William Coley. However, its role in lung cancer remains unclear. The aim of our study was to elucidate the dose-dependent effects of LPS (0.1-10 µg/mouse) in a mouse model of B16-F10-induced metastatic lung cancer. Lung tumor growth increased at 3 and 7 d after the administration of low-dose LPS (0.1 µg/mouse) compared with control mice. This was associated with an influx of plasmacytoid dendritic cells (pDCs), regulatory T cells, myeloid-derived suppressor cells, and CD8(+) regulatory T cells. In contrast, high-dose LPS (10 µg/mouse) reduced lung tumor burden and was associated with a greater influx of pDCs, as well as a stronger Th1 and Th17 polarization. Depletion of pDCs during low-dose LPS administration resulted in a decreased lung tumor burden. Depletion of pDCs during high-dose LPS treatment resulted in an increased tumor burden. The dichotomy in LPS effects was due to the phenotype of pDCs, which were immunosuppressive after the low-dose LPS, and Th1- and T cytotoxic-polarizing cells after the high-dose LPS. Adoptive transfer of T cells into nude mice demonstrated that CD8(+) T cells were responsible for pDC recruitment following low-dose LPS administration, whereas CD4(+) T cells were required for pDC influx after the high-dose LPS. In conclusion, our data suggest differential effects of low-dose versus high-dose LPS on pDC phenotype and tumor progression or regression in the lungs of mice.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Lipopolissacarídeos/farmacologia , Neoplasias Pulmonares/patologia , Melanoma Experimental/patologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/transplante , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/patologia , Progressão da Doença , Relação Dose-Resposta Imunológica , Feminino , Lipopolissacarídeos/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Linfonodos/efeitos dos fármacos , Linfonodos/imunologia , Linfonodos/patologia , Ativação Linfocitária/efeitos dos fármacos , Teste de Cultura Mista de Linfócitos , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/imunologia , Camundongos , Camundongos Nus , Baço/efeitos dos fármacos , Baço/imunologia , Baço/patologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/patologia , Linfócitos T Reguladores/transplante , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/patologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/patologia
8.
J Immunol ; 188(11): 5357-64, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22516955

RESUMO

Polyinosinic-polycytidylic acid (poly I:C), a TLR3 ligand, is currently being tested in human clinical trials as an adjuvant to anti-cancer vaccines and in combination with other therapies. However, little is known about its activity in established pulmonary metastasis. The aim of our study was to elucidate the effect of poly I:C (1, 10, or 100 µg/mouse) in a mouse model of B16-F10-induced metastatic lung cancer. Lung tumor growth was arrested after a single administration of poly I:C. This was associated with higher influx of mature dendritic cells (DCs), which drove toward a Th1-like, Th17-like, and cytotoxic immune environment. The interference with IFN type I receptor signaling by means of a specific mAb reversed poly I:C-mediated tumor regression due to lower presence of myeloid DCs, cytotoxic DCs (CD11c(+)CD8(+)), NKT cells, CD8(+) T cells, and Th1-like cytokines. Moreover, the adoptive transfer of poly I:C-activated bone marrow-derived DCs into tumor-bearing mice resulted in activities similar to those of the systemic administration of poly I:C on lung tumor burden. In conclusion, our data prove that poly I:C has potential anti-tumor activity in a mouse model of established pulmonary metastasis. The activation of DCs and the production of IFN type I are responsible for an effective T cytotoxic immune response against metastatic lung cancer progression after poly I:C treatment.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Pulmonares/prevenção & controle , Neoplasias Pulmonares/secundário , Melanoma Experimental/patologia , Melanoma Experimental/prevenção & controle , Poli I-C/administração & dosagem , Transferência Adotiva , Animais , Antineoplásicos/uso terapêutico , Transplante de Medula Óssea/imunologia , Transplante de Medula Óssea/patologia , Células Cultivadas , Células Dendríticas/transplante , Feminino , Neoplasias Pulmonares/patologia , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/uso terapêutico
9.
J Immunol ; 189(5): 2226-33, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22826317

RESUMO

CD73 is a cell surface enzyme that suppresses T cell-mediated immune responses by producing extracellular adenosine. Growing evidence suggests that targeting CD73 in cancer may be useful for an effective therapeutic outcome. In this study, we demonstrate that administration of a specific CD73 inhibitor, adenosine 5'-(α,ß-methylene)diphosphate (APCP), to melanoma-bearing mice induced a significant tumor regression by promoting the release of Th1- and Th17-associated cytokines in the tumor microenvironment. CD8+ T cells were increased in melanoma tissue of APCP-treated mice. Accordingly, in nude mice APCP failed to reduce tumor growth. Importantly, we observed that after APCP administration, the presence of B cells in the melanoma tissue was greater than that observed in control mice. This was associated with production of IgG2b within the melanoma. Depletion of CD20+ B cells partially blocked the anti-tumor effect of APCP and significantly reduced the production of IgG2b induced by APCP, implying a critical role for B cells in the anti-tumor activity of APCP. Our results also suggest that APCP could influence B cell activity to produce IgG through IL-17A, which significantly increased in the tumor tissue of APCP-treated mice. In support of this, we found that in melanoma-bearing mice receiving anti-IL-17A mAb, the anti-tumor effect of APCP was ablated. This correlated with a reduced capacity of APCP-treated mice to mount an effective immune response against melanoma, as neutralization of this cytokine significantly affected both the CD8+ T cell- and B cell-mediated responses. In conclusion, we demonstrate that both T cells and B cells play a pivotal role in the APCP-induced anti-tumor immune response.


Assuntos
5'-Nucleotidase/antagonistas & inibidores , 5'-Nucleotidase/fisiologia , Difosfato de Adenosina/análogos & derivados , Linfócitos B/imunologia , Modelos Animais de Doenças , Melanoma Experimental/imunologia , Difosfato de Adenosina/farmacologia , Difosfato de Adenosina/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Células Th17/metabolismo
10.
Front Microbiol ; 15: 1335985, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322314

RESUMO

Five mycobacterial isolates from sewage were classified as members of the genus Mycobacterium but presented inconclusive species assignments. Thus, the isolates (MYC017, MYC098, MYC101, MYC123 and MYC340) were analyzed by phenotypical, biochemical, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and genomic features to clarify their taxonomic position. Phenotypic analysis and biochemical tests did not distinguish these isolates from other non-pigmented mycobacteria. In contrast, MALDI-TOF MS analysis showed that isolates were not related to any previously described Mycobacterium species. Comparative genomic analysis showed values of ANI and dDDH between 81.59-85.56% and 24.4-28.8%, respectively, when compared to the genomes of species of this genus. In addition, two (MYC101 and MYC123) presented indistinguishable protein spectra from each other and values of ANI = 98.57% and dDDH = 97.3%, therefore being considered as belonging to the same species. Phylogenetic analysis grouped the five isolates within the Mycobacterium terrae complex (MTC) but in a specific subclade and separated from the species already described and supported by 100% bootstrap value, confirming that they are part of this complex but different from earlier described species. According to these data, we propose the description of four new species belonging to the Mycobacterium genus: (i) Mycobacterium defluvii sp. nov. strain MYC017T (= ATCC TSD-296T = JCM 35364T), (ii) Mycobacterium crassicus sp. nov. strain MYC098T (= ATCC TSD-297T = JCM 35365T), (iii) Mycobacterium zoologicum sp. nov. strain MYC101T (= ATCC TSD-298T = JCM 35366T) and MYC123 (= ATCC BAA-3216 = JCM 35367); and (iv) Mycobacterium nativiensis sp. nov. strain MYC340T (= ATCC TSD-299T = JCM 35368T).

11.
Dev Biol ; 361(1): 177-85, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22027434

RESUMO

The hierarchy of the segmentation cascade responsible for establishing the Drosophila body plan is composed by gap, pair-rule and segment polarity genes. However, no pair-rule stripes are formed in the anterior regions of the embryo. This lack of stripe formation, as well as other evidence from the literature that is further investigated here, led us to the hypothesis that anterior gap genes might be involved in a combinatorial mechanism responsible for repressing the cis-regulatory modules (CRMs) of hairy (h), even-skipped (eve), runt (run), and fushi-tarazu (ftz) anterior-most stripes. In this study, we investigated huckebein (hkb), which has a gap expression domain at the anterior tip of the embryo. Using genetic methods we were able to detect deviations from the wild-type patterns of the anterior-most pair-rule stripes in different genetic backgrounds, which were consistent with Hkb-mediated repression. Moreover, we developed an image processing tool that, for the most part, confirmed our assumptions. Using an hkb misexpression system, we further detected specific repression on anterior stripes. Furthermore, bioinformatics analysis predicted an increased significance of binding site clusters in the CRMs of h 1, eve 1, run 1 and ftz 1when Hkb was incorporated in the analysis, indicating that Hkb plays a direct role in these CRMs. We further discuss that Hkb and Slp1, which is the other previously identified common repressor of anterior stripes, might participate in a combinatorial repression mechanism controlling stripe CRMs in the anterior parts of the embryo and define the borders of these anterior stripes.


Assuntos
Blastoderma/metabolismo , Padronização Corporal/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/embriologia , Proteínas Repressoras/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação/genética , Blastoderma/embriologia , Biologia Computacional , Embrião não Mamífero/anatomia & histologia , Embrião não Mamífero/embriologia , Embrião não Mamífero/metabolismo , Fatores de Transcrição Fushi Tarazu/metabolismo , Proteínas de Homeodomínio/metabolismo , Processamento de Imagem Assistida por Computador , Hibridização In Situ , Proteínas Nucleares/metabolismo , Fatores de Transcrição/metabolismo
12.
Nutrients ; 15(3)2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36771270

RESUMO

Trimethylamine N-oxide (TMAO) is a microbial metabolite derived from nutrients, such as choline, L-carnitine, ergothioneine and betaine. Recently, it has come under the spotlight for its close interactions with gut microbiota and implications for gastrointestinal cancers, cardiovascular disease, and systemic inflammation. The culprits in the origin of these pathologies may be food sources, in particular, high fat meat, offal, egg yolk, whole dairy products, and fatty fish, but intercalated between these food sources and the production of pro-inflammatory TMAO, the composition of gut microbiota plays an important role in modulating this process. The aim of this review is to explain how the gut microbiota interacts with the conversion of specific compounds into TMA and its oxidation to TMAO. We will first cover the correlation between TMAO and various pathologies such as dysbiosis, then focus on cardiovascular disease, with a particular emphasis on pro-atherogenic factors, and then on systemic inflammation and gastrointestinal cancers. Finally, we will discuss primary prevention and therapies that are or may become possible. Possible treatments include modulation of the gut microbiota species with diets, physical activity and supplements, and administration of drugs, such as metformin and aspirin.


Assuntos
Doenças Cardiovasculares , Microbiota , Neoplasias , Animais , Colina/metabolismo , Metilaminas/metabolismo , Inflamação , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle
13.
Res Vet Sci ; 161: 110-117, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37356405

RESUMO

Laminitis is usually considered a consequence of digestive disorders that reduce ruminal pH. However, it is still not clear the direct relation between low ruminal pH provoked by excessive fast-digesting carbohydrate ingestion and laminitis, considering indicators, signs, and diagnosis aspects. This study aimed to clarify the association between different clinical presentations of laminitis with ruminal acidosis provoked by diet using the systematic review methodology. Three electronic databases were used: ISI Web of Science, PubMed, and Scopus. A total of 339 manuscripts were identified and only 16 were included. Manuscripts were published between 2000 and 2021 in 11 different peer-reviewed journals. Fifteen studies confirmed the occurrence of ruminal acidosis. The main indicators used were ruminal pH and clinical signs, such as anorexia, depression, discomfort and diarrhea. Two of the studies that administered oligofructose to induce acidosis and acute laminitis did not observe clinical signs of laminitis, using lameness score or hooves' sensitivity as an indicator. Various diagnostic methods were used to describe laminitis, like thermography, hoof biopsy, sensitivity test, and visual inspection. Although the variety of laminitis indicators used in the included studies, we evidence the existence of an association between diet (high level of fast-digesting carbohydrates), ruminal acidosis, and acute laminitis, mostly in the short-term acidosis' induction protocols, but the mechanism of action is still not clear.


Assuntos
Acidose , Doenças dos Bovinos , Dermatite , Animais , Bovinos , Acidose/veterinária , Dermatite/veterinária , Dieta/veterinária , Concentração de Íons de Hidrogênio , Rúmen
15.
Cancers (Basel) ; 15(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37046851

RESUMO

Non-small cell lung cancer (NSCLC), the leading cause of cancer death worldwide, is still an unmet medical problem due to the lack of both effective therapies against advanced stages and markers to allow a diagnosis of the disease at early stages before its progression. Immunotherapy targeting the PD-1/PD-L1 checkpoint is promising for many cancers, including NSCLC, but its success depends on the tumor expression of PD-L1. PATZ1 is an emerging cancer-related transcriptional regulator and diagnostic/prognostic biomarker in different malignant tumors, but its role in lung cancer is still obscure. Here we investigated expression and role of PATZ1 in NSCLC, in correlation with NSCLC subtypes and PD-L1 expression. A cohort of 104 NSCLCs, including lung squamous cell carcinomas (LUSCs) and adenocarcinomas (LUADs), was retrospectively analyzed by immunohistochemistry for the expression of PATZ1 and PD-L1. The results were correlated with each other and with the clinical characteristics, showing on the one hand a positive correlation between the high expression of PATZ1 and the LUSC subtype and, on the other hand, a negative correlation between PATZ1 and PD-L1, validated at the mRNA level in independent NSCLC datasets. Consistently, two NSCLC cell lines transfected with a PATZ1-overexpressing plasmid showed PD-L1 downregulation, suggesting a role for PATZ1 in the negative regulation of PD-L1. We also showed that PATZ1 overexpression inhibits NSCLC cell proliferation, migration, and invasion, and that Patz1-knockout mice develop LUAD. Overall, this suggests that PATZ1 may act as a tumor suppressor in NSCLC.

16.
Int J Pharm ; 633: 122618, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36657553

RESUMO

Surface functionalization of nanoparticles (NPs) with tumor-targeting peptides is an emerging approach with a huge potential to translate in the clinic and ameliorate the efficacy of nano-oncologicals. One major challenge is to find straightforward strategies for anchoring peptides on the surface of biodegradable NPs and ensuring their correct exposure and orientation to bind the target receptor. Here, we propose a non-covalent strategy to functionalize polyester aminic NPs based on the formation of either electrostatic or lipophilic interactions between NPs and the peptide modified with an anchoring moiety. We selected an iNGRt peptide containing a CendR motif (CRNGR) targeting neuropilin receptor 1 (NRP-1), which is upregulated in several cancers. iNGRt was linked with either a short poly(glutamic acid) chain (polyE) or a palmitoyl chain (Palm) and used to functionalize the surface of NPs made of a diamine poly(ε-caprolactone). iNGRt-PolyE was adsorbed on preformed cationic NPs through electrostatic interaction, whereas iNGRt-Palm was integrated into the forming NPs through interactions. In both cases, peptides were strongly associated with NPs of ∼100 nm, low polydispersity indexes, and positive zeta potential values. NPs entered MDA-MB231 breast cancer cells overexpressing NRP-1 via receptor-mediated endocytosis and showed a different cell localization depending on the mode of peptide anchoring. When loaded with the lipophilic anticancer drug docetaxel (DTX), NPs functionalized with the iNGRt-Palm variant exerted a time- and dose-dependent cytotoxicity similar to DTX in MDA-MB-231 cells but were less toxic than DTX toward control MRC-5 human fibroblasts, not expressing NRP-1. In a heterotopic mouse model of triple negative breast cancer, iNGRt-Palm NPs were tolerated better than free DTX and demonstrated superior anticancer activity and survival compared to both free DTX and NPs without peptide functionalization. We foresee that the functionalization strategy with palmitoylated peptides proposed here can be extended to other biodegradable NPs and peptide sequences designed for therapeutic or targeting purposes.


Assuntos
Antineoplásicos , Nanopartículas , Neoplasias de Mama Triplo Negativas , Camundongos , Animais , Humanos , Docetaxel , Antineoplásicos/farmacologia , Polímeros , Peptídeos , Linhagem Celular Tumoral , Portadores de Fármacos
17.
Cell Death Dis ; 14(9): 613, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37723219

RESUMO

The ß2-Adrenergic receptor (ß2-ARs) is a cell membrane-spanning G protein-coupled receptors (GPCRs) physiologically involved in stress-related response. In many cancers, the ß2-ARs signaling drives the tumor development and transformation, also promoting the resistance to the treatments. In HNSCC cell lines, the ß2-AR selective inhibition synergistically amplifies the cytotoxic effect of the MEK 1/2 by affecting the p38/NF-kB oncogenic pathway and contemporary reducing the NRF-2 mediated antioxidant cell response. In this study, we aimed to validate the anti-tumor effect of ß2-AR blockade and the synergism with MEK/ERK and EGFR pathway inhibition in a pre-clinical orthotopic mouse model of HNSCC. Interestingly, we found a strong ß2-ARs expression in the tumors that were significantly reduced after prolonged treatment with ß2-Ars inhibitor (ICI) and EGFR mAb Cetuximab (CTX) in combination. The ß2-ARs down-regulation correlated in mice with a significant tumor growth delay, together with the MAPK signaling switch-off caused by the blockade of the MEK/ERK phosphorylation. We also demonstrated that the administration of ICI and CTX in combination unbalanced the cell ROS homeostasis by blocking the NRF-2 nuclear translocation with the relative down-regulation of the antioxidant enzyme expression. Our findings highlighted for the first time, in a pre-clinical in vivo model, the efficacy of the ß2-ARs inhibition in the treatment of the HNSCC, remarkably in combination with CTX, which is the standard of care for unresectable HNSCC.


Assuntos
Antioxidantes , Neoplasias de Cabeça e Pescoço , Animais , Camundongos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Estresse Oxidativo , Anticorpos , Cetuximab/farmacologia , Cetuximab/uso terapêutico , Receptores ErbB , Quinases de Proteína Quinase Ativadas por Mitógeno
18.
Front Public Health ; 11: 1219661, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37663860

RESUMO

Background: Self-management of Type 2 diabetes mellitus (T2D) is challenging. Regular self-monitoring of blood glucose and healthy lifestyles are required to improve glycometabolic control, thus delaying diabetes complications, and reducing hospitalizations. Digital technologies can empower patients in their disease management promoting self-management and motivation to change behaviors. We report the results of an exploratory trial aimed at evaluating the metabolic outcomes of using digital solutions for T2D self-management developed in the ProEmpower project, a European Commission funded Pre-Commercial Procurement. Methods: Two digital solutions, DM4All and DiaWatch, which were codesigned with providers, patients, and caregivers, enabled the collection of clinical parameters by the patient using a smartphone integrated with the medical devices (glucometer, sphygmomanometer, scale, smart watch for heart rate monitoring and step counter). Data were automatically sent to the shared care plan allowing professionals to monitor adherence to treatment, set goals, and communicate more effectively with patients. At baseline and after an average follow-up of 8 months, glycosylated hemoglobin (HbA1c), body weight, blood pressure, and blood lipids were measured in 100 T2D patients using the ProEmpower solutions across different diabetes centers in Campania Region, age 45-79 years, both genders, and compared with a Control cohort of T2D patients (n = 100) with similar clinical characteristics and followed for a comparable period of observation in the same centers. Results: At baseline, the ProEmpower participants and the Control subjects were on average overweight, with a similar BMI in the two cohorts, and mean HbA1c was at acceptable levels (around 7.0%). After the 8 month exploratory trial, body weight, HbA1c, systolic and diastolic blood pressure, and plasma and LDL-cholesterol significantly decreased in the ProEmpower participants compared to baseline (p < 0.05 for all). The changes in systolic and diastolic blood pressure, and plasma and LDL-cholesterol were significantly different from those observed in the Control cohort (p < 0.05 for all). Conclusion: This pilot study showed positive effects on metabolic outcomes relevant to cardiovascular risk in T2D of adopting digital telemedicine self-monitoring solutions based on automation of measurements and coaching on healthy lifestyles promotion.


Assuntos
Diabetes Mellitus Tipo 2 , Autogestão , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peso Corporal , LDL-Colesterol , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Projetos Piloto
19.
PLoS One ; 18(1): e0279537, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36595526

RESUMO

The model selection stage has become a central theme in applying the additive main effects and multiplicative interaction (AMMI) model to determine the optimal number of bilinear components to be retained to describe the genotype-by-environment interaction (GEI). In the Bayesian context, this problem has been addressed by using information criteria and the Bayes factor. However, these procedures are computationally intensive, making their application unfeasible when the model's parametric space is large. A Bayesian analysis of the AMMI model was conducted using the Reversible Jump algorithm (RJMCMC) to determine the number of multiplicative terms needed to explain the GEI pattern. Three a priori distributions were assigned for the singular value scale parameter under different justifications, namely: i) the insufficient reason principle (uniform); ii) the invariance principle (Jeffreys' prior) and iii) the maximum entropy principle. Simulated and real data were used to exemplify the method. An evaluation of the predictive ability of models for simulated data was conducted and indicated that the AMMI analysis, in general, was robust, and models adjusted by the Reversible Jump method were superior to those in which sampling was performed only by the Gibbs sampler. In addition, the RJMCMC showed greater feasibility since the selection and estimation of parameters are carried out concurrently in the same sampling algorithm, being more attractive in terms of computational time. The use of the maximum entropy principle makes the analysis more flexible, avoiding the use of procedures for correcting prior degrees of freedom and obtaining improper posterior marginal distributions.


Assuntos
Ammi , Cadeias de Markov , Teorema de Bayes , Algoritmos , Método de Monte Carlo
20.
Microorganisms ; 11(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37374915

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are chemical compounds that are widespread in the environment, arising from the incomplete combustion of organic material, as well as from human activities involving petrol exploitation, petrochemical industrial waste, gas stations, and environmental disasters. PAHs of high molecular weight, such as pyrene, have carcinogenic and mutagenic effects and are considered pollutants. The microbial degradation of PAHs occurs through the action of multiple dioxygenase genes (nid), which are localized in genomic island denominate region A, and cytochrome P450 monooxygenases genes (cyp) dispersed in the bacterial genome. This study evaluated pyrene degradation by five isolates of Mycolicibacterium austroafricanum using 2,6-dichlorophenol indophenol (DCPIP assay), gas chromatography/mass spectrometry (CG/MS), and genomic analyses. Two isolates (MYC038 and MYC040) exhibited pyrene degradation indexes of 96% and 88%, respectively, over a seven-day incubation period. Interestingly, the genomic analyses showed that the isolates do not have nid genes, which are involved in PAH biodegradation, despite their ability to degrade pyrene, suggesting that degradation may occur due to the presence of cyp150 genes, or even genes that have not yet been described. To the best of our knowledge, this is the first report of isolates without nid genes demonstrating the ability to degrade pyrene.

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