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1.
Glycobiology ; 25(4): 386-93, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25367817

ABSTRACT

Inflammation and cancer are related pathologies acting synergistically to promote tumor progression. In both, hematogenous metastasis and inflammation, P-selectin participates in interactions involving tumor cells, platelets, leukocytes and endothelium. Heparin has been shown to inhibit P-selectin and as a consequence it blunts metastasis and inflammation. Some heparin analogs obtained from marine invertebrates are P-selectin inhibitors and do not induce bleeding effects. The present work focuses on the P-selectin blocking activity of a unique heparan sulfate (HS) from the bivalve mollusk Nodipecten nodosus. Initially, we showed that the mollusk HS inhibited LS180 colon carcinoma cell adhesion to immobilized P-selectin in a dose-dependent manner. In addition, we demonstrated that this glycan attenuates leukocyte rolling on activated endothelium and inflammatory cell recruitment in thioglycollate-induced peritonitis in mice. Biochemical analysis indicated that the invertebrate glycan also inhibits heparanase, a key player in cell invasion and metastasis. Experimental metastasis of Lewis lung carcinoma cells was drastically attenuated by the mollusk HS through a mechanism involving inhibition of platelet-tumor-cell complex formation in blood vessels. These data suggest that the mollusk HS is a potential alternative to heparin for inhibiting P-selectin-mediated events such as metastasis and inflammatory cell recruitment.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Lewis Lung/drug therapy , Heparitin Sulfate/pharmacology , Lung Neoplasms/prevention & control , Animals , Anticoagulants/pharmacology , Antineoplastic Agents/therapeutic use , Blood Platelets/drug effects , Blood Platelets/physiology , Carcinoma, Lewis Lung/secondary , Cell Adhesion , Cell Line, Tumor , Drug Screening Assays, Antitumor , Glucuronidase/antagonists & inhibitors , Glucuronidase/chemistry , Heparitin Sulfate/therapeutic use , Humans , Inhibitory Concentration 50 , Leukocyte Rolling/drug effects , Lung Neoplasms/secondary , Mollusca , Neoplasm Transplantation , P-Selectin/antagonists & inhibitors , P-Selectin/metabolism
2.
Hist. ciênc. saúde-Manguinhos ; Hist. ciênc. saúde-Manguinhos;21(4): 1131-1149, Oct-Dec/2014.
Article in Portuguese | LILACS | ID: lil-732507

ABSTRACT

Associadas a projetos de construção da ideia de nação, no Brasil monárquico foram encaminhadas, pelo governo imperial, algumas iniciativas no sentido de materializar propostas de educação física. O objetivo deste artigo é investigar os sentidos e significados atribuídos ao tema na legislação e nos relatórios anuais do Ministério dos Negócios do Império (1831-1889), com especial interesse pelo que se refere ao Rio de Janeiro. A abordagem do assunto nas fontes pesquisadas evidencia que as visões sobre a educação física se deram a partir de uma matriz que articulava concepções de moral, saúde e civilização, tendo que lidar com as condições concretas de um país recém-independente, periférico e com uma burocracia ainda em formação.


In association with its nation building projects, the imperial government in Brazil under monarchic rule took some concrete actions based on proposals for physical education. The aim of this article is to investigate the meanings and significations attributed to this subject in the legislation and the annual reports issued by the Ministry of Business of the Empire (1831-1889), giving special attention to Rio de Janeiro. The approach to the subject in the sources researched demonstrates that the views of physical education took shape through a web of ideas that associated moral, health and civilization conceptions, in a bid to deal with the concrete circumstances of a newly independent peripheral nation with a bureaucratic structure in the process of formation.


Subject(s)
Animals , Female , Mice , Carcinoma, Lewis Lung/secondary , Cathepsin B/antagonists & inhibitors , Cathepsins/antagonists & inhibitors , Endopeptidases , Leucine/analogs & derivatives , Liver Neoplasms, Experimental/prevention & control , Liver Neoplasms, Experimental/secondary , Neoplasm Invasiveness/prevention & control , Cathepsin L , Collagen , Cysteine Endopeptidases , Carcinoma, Lewis Lung/metabolism , Drug Combinations , Drug Screening Assays, Antitumor , Laminin , Leucine/pharmacokinetics , Leucine/pharmacology , Liver Neoplasms, Experimental/enzymology , Proteoglycans , Tumor Cells, Cultured
3.
Clinics (Sao Paulo) ; 67(8): 901-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22948457

ABSTRACT

OBJECTIVES: Tumor-associated macrophages that generally exhibit an alternatively activated (M2) phenotype have been linked to tumor progression and metastasis. However, the role of M2-polarized macrophages in the growth and metastasis of lung adenocarcinoma remains enigmatic. The aim of this study was to explore the effect of M2 macrophages on the proliferation and migration of mouse Lewis lung carcinoma cells and tumor-induced lymphangiogenesis. METHODS: Trypan blue staining and the Transwell migration assay were performed to evaluate the effects of activated (M1 or M2) macrophages on the proliferation and migration of Lewis cells. Furthermore, vascular endothelial growth factor-C expression in Lewis cells and nitric oxide secretion from activated macrophages were detected during the co-culture assay. Following treatment with activated macrophages, lymphatic endothelial cells differentiated into capillary-like structures, and the induction of Lewis cell migration was assessed using a two-dimensional Matrigel-based assay. RESULTS: In the co-culture Transwell system, the proliferation and migration of Lewis cells were promoted by M2 macrophages. Moreover, the co-culture significantly increased the expression of vascular endothelial growth factor-C by Lewis cells and reduced the secretion of nitric oxide from M2 macrophages, which subsequently led to the capillary morphogenesis of lymphatic endothelial cells. Interestingly, following co-culture with Lewis cells, the function of RAW264.7 cells was polarized toward that of the M2 macrophage phenotype. CONCLUSION: M2-polarized macrophages promoted the metastatic behavior of Lewis cells by inducing vascular endothelial growth factor-C expression. Thus, the interruption of signaling between M2 macrophages and Lewis cells may be considered to be a new therapeutic strategy.


Subject(s)
Carcinoma, Lewis Lung/secondary , Lung Neoplasms/pathology , Macrophages/physiology , Vascular Endothelial Growth Factor C/metabolism , Animals , Carcinoma, Lewis Lung/metabolism , Cell Line, Tumor , Cell Migration Assays , Cell Movement , Cell Proliferation , Endothelial Cells/pathology , Lung Neoplasms/metabolism , Lymphangiogenesis/physiology , Macrophages/cytology , Mice , Time Factors , Vascular Endothelial Growth Factor C/physiology
4.
Clinics ; Clinics;67(8): 901-906, Aug. 2012. ilus, graf
Article in English | LILACS | ID: lil-647793

ABSTRACT

OBJECTIVES: Tumor-associated macrophages that generally exhibit an alternatively activated (M2) phenotype have been linked to tumor progression and metastasis. However, the role of M2-polarized macrophages in the growth and metastasis of lung adenocarcinoma remains enigmatic. The aim of this study was to explore the effect of M2 macrophages on the proliferation and migration of mouse Lewis lung carcinoma cells and tumor-induced lymphangiogenesis. METHODS: Trypan blue staining and the Transwell migration assay were performed to evaluate the effects of activated (M1 or M2) macrophages on the proliferation and migration of Lewis cells. Furthermore, vascular endothelial growth factor-C expression in Lewis cells and nitric oxide secretion from activated macrophages were detected during the co-culture assay. Following treatment with activated macrophages, lymphatic endothelial cells differentiated into capillary-like structures, and the induction of Lewis cell migration was assessed using a twodimensional Matrigel-based assay. RESULTS: In the co-culture Transwell system, the proliferation and migration of Lewis cells were promoted by M2 macrophages. Moreover, the co-culture significantly increased the expression of vascular endothelial growth factor-C by Lewis cells and reduced the secretion of nitric oxide from M2 macrophages, which subsequently led to the capillary morphogenesis of lymphatic endothelial cells. Interestingly, following co-culture with Lewis cells, the function of RAW264.7 cells was polarized toward that of the M2 macrophage phenotype. CONCLUSION: M2-polarized macrophages promoted the metastatic behavior of Lewis cells by inducing vascular endothelial growth factor-C expression. Thus, the interruption of signaling between M2 macrophages and Lewis cells may be considered to be a new therapeutic strategy.


Subject(s)
Animals , Mice , Carcinoma, Lewis Lung/secondary , Lung Neoplasms/pathology , Macrophages/physiology , Vascular Endothelial Growth Factor C/metabolism , Cell Line, Tumor , Cell Migration Assays , Cell Movement , Cell Proliferation , Carcinoma, Lewis Lung/metabolism , Endothelial Cells/pathology , Lung Neoplasms/metabolism , Lymphangiogenesis/physiology , Macrophages/cytology , Time Factors , Vascular Endothelial Growth Factor C/physiology
5.
J Immunol ; 187(10): 4954-66, 2011 Nov 15.
Article in English | MEDLINE | ID: mdl-21984704

ABSTRACT

Despite promising results in the use of anti-epidermal growth factor receptor (EGFR) Abs for cancer therapy, several issues remain to be addressed. An increasing emphasis is being placed on immune effector mechanisms. It has become clear for other Abs directed to tumor targets that their effects involve the adaptive immunity, mainly by the contribution of Fc region-mediated mechanisms. Given the relevance of EGFR signaling for tumor biology, we wonder whether the oncogene inhibition could contribute to Ab-induced vaccine effect. In a mouse model in which 7A7 (an anti-murine EGFR Ab) and AG1478 (an EGFR-tyrosine kinase inhibitor) displayed potent antimetastatic activities, depletion experiments revealed that only in the case of the Ab, the effect was dependent on CD4(+) and CD8(+) T cells. Correspondingly, 7A7 administration elicited a remarkable tumor-specific CTL response in hosts. Importantly, experiments using 7A7 F(ab')(2) suggested that in vivo Ab-mediated EGFR blockade may play an important role in the linkage with adaptive immunity. Addressing the possible mechanism involved in this effect, we found quantitative and qualitative differences between 7A7 and AG1478-induced apoptosis. EGFR blocking by 7A7 not only prompted a higher proapoptotic effect on tumor metastases compared with AG1478, but also was able to induce apoptosis with immunogenic potential in an Fc-independent manner. As expected, 7A7 but not AG1478 stimulated exposure of danger signals on tumor cells. Subcutaneous injection of 7A7-treated tumor cells induced an antitumor immune response. This is the first report, to our knowledge, of a tumor-specific CTL response generated by Ab-mediated EGFR inhibition, suggesting an important contribution of immunogenic apoptosis to this effect.


Subject(s)
Antibodies, Monoclonal/physiology , Antibody Specificity/physiology , Apoptosis/immunology , Carcinoma, Lewis Lung/immunology , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/immunology , Animals , Antibodies, Blocking/physiology , Carcinoma, Lewis Lung/pathology , Carcinoma, Lewis Lung/secondary , Cell Line, Tumor , Cells, Cultured , ErbB Receptors/metabolism , Female , Immunoglobulin Fc Fragments/physiology , Lung Neoplasms/immunology , Lung Neoplasms/pathology , Melanoma, Experimental/immunology , Melanoma, Experimental/pathology , Melanoma, Experimental/prevention & control , Mice , Mice, Inbred C57BL , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , T-Lymphocytes, Cytotoxic/pathology
6.
Angiogenesis ; 10(1): 23-34, 2007.
Article in English | MEDLINE | ID: mdl-17273909

ABSTRACT

Passive immunotherapy against soluble pro-angiogenic factors and/or their receptors in endothelial cells has become a promising approach in cancer therapeutics. There is also experimental evidence indicating that an active immunotherapy strategy directed towards these target molecules could also be effective. In this paper we show that it is possible to reduce tumor growth or increase the survival of tumor-bearing C57Bl/6 mice when animals are vaccinated with the human vascular endothelial growth factor (VEGF) isoform 121 gene (hVEGF(121)), and later challenged with melanoma or lung carcinoma tumor cells. Immunization was done with 10 microg DNA doses of the hVEGF121 gene, which is highly homologous to its mouse counterpart, administered on a weekly basis using a plasmid bearing 5 CpG bacterial motifs. Histopathology analyses of tumors of hVEGF(121) immunized animals showed a decrease in tumor cell density around vessels and in mitotic figures, as well as an increase in apoptotic tumor cells. A statistically significant cell cytotoxic response was found when spleen cells of immunized mice were co-cultured in vitro with mouse tumor VEGF-producing cells. Vaccination with an hVEGF121 gene mutated to make it deficient for VEGF receptor binding, produced similar in vitro and in vivo results, and significantly reduced the number of spontaneous metastases produced by the mouse Lewis lung carcinoma. Our results indicate that human VEGF DNA can be employed for anti-angiogenic active immunotherapy in mice, and that direct cell cytotoxicity is a contributor mechanism to the overall anti-tumor effects seen in immunized animals.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Cancer Vaccines/therapeutic use , Carcinoma, Lewis Lung/prevention & control , Melanoma, Experimental/prevention & control , Vaccines, DNA/therapeutic use , Vascular Endothelial Growth Factor A/therapeutic use , Angiogenesis Inhibitors/immunology , Animals , Cancer Vaccines/immunology , Carcinoma, Lewis Lung/blood supply , Carcinoma, Lewis Lung/secondary , Cell Line, Tumor , Female , Gene Transfer Techniques , Genetic Therapy/methods , Humans , Immunohistochemistry , Interferon-gamma/immunology , Lung Neoplasms/prevention & control , Lung Neoplasms/secondary , Melanoma, Experimental/blood supply , Melanoma, Experimental/secondary , Mice , Mice, Inbred C57BL , Neovascularization, Pathologic/physiopathology , Neovascularization, Pathologic/prevention & control , Receptors, Vascular Endothelial Growth Factor/metabolism , Vaccines, DNA/immunology
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