title: Differential Contribution of Acute and Chronic Inflammation to the Development of Murine Mammary 4T1 Tumors.
abstract: Based on the notion that inflammation favors tumorigenesis, our experiments comparatively assessed the influence of acute and chronic inflammation on the development of a murine mammary tumor (4T1). In addition, we characterized angiogenic and inflammatory markers in the tumor tissue and systemically. Subcutaneous implantation of polyether-polyurethane sponge discs in Balb/c mice was used to host 4T1 tumor cells (1x10(6)), which were inoculated intraimplant 24 h or 10 days post implantation. Flow cytometric analysis of enzyme-digested implants revealed that, after 24 hours, the population of leukocytes was primarily characterized by neutrophils (42.53% +/- 8.45) and monocytes (37.53% +/- 7.48), with some lymphocytes (16.27% +/- 4.0) and a few dendritic cells (1.82% +/- 0.36). At 10 days, macrophages were predominant (37.10% +/- 4.54), followed by lymphocytes (28.1% +/- 4.77), and monocytes (22.33% +/- 3.05), with some dendritic cells (13.60% +/- 0.55) and neutrophils (11.07% +/- 2.27). A mammary tumor grown in a chronic inflammatory environment was 2-fold when compared with one grown in acute inflammation and 5-fold when compared with tumor alone. The levels of pro-angiogenic cytokine (VEGF-Vascular Endothelial Growth Factor) were higher in implant-bearing tumor when 4T1 cells were grown in 10-day old implants as compared to the VEGF levels of the two other groups. Overall, the levels of the inflammatory markers evaluated (NAG -N-acetylglucosaminidase, TNF-α-Tumor Necrosis Factor-α) were higher in both groups of implant-bearing tumors and in serum from those animals when compared with the tumor alone levels. This inflammation-related difference in tumor growth may provide new insights into the contribution of different inflammatory cell populations to cancer progression.
authors.affiliation: Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Celso Tarso
authors.initials: CT
authors.lastname: Rodrigues Viana
authors.affiliation: Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Pollyana Ribeiro
authors.initials: PR
authors.lastname: Castro
authors.affiliation: Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Suzane Motta
authors.initials: SM
authors.lastname: Marques
authors.affiliation: Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Miriam Teresa
authors.initials: MT
authors.lastname: Paz Lopes
authors.affiliation: Department of General Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Gonçalves
authors.affiliation: Department of General Pathology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Paula Peixoto
authors.initials: PP
authors.lastname: Campos
authors.affiliation: Department of Physiology and Biophysics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Silvia Passos
authors.initials: SP
authors.lastname: Andrade
mesh_terms: D000118:Acetylglucosaminidase / Q000276:immunology / Q000378:metabolism; D000208:Acute Disease; D000818:Animals; D014408:Biomarkers, Tumor / Q000276:immunology* / Q000378:metabolism; D002908:Chronic Disease; D018450:Disease Progression; D005434:Flow Cytometry; D007249:Inflammation / Q000276:immunology* / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000098:blood supply / Q000276:immunology* / Q000378:metabolism; D008807:Mice, Inbred BALB C; D009000:Monocytes / Q000276:immunology / Q000378:metabolism; D009389:Neovascularization, Pathologic / Q000276:immunology* / Q000378:metabolism; D009504:Neutrophils / Q000276:immunology / Q000378:metabolism; D009195:Peroxidase / Q000276:immunology / Q000378:metabolism; D013997:Time Factors; D047368:Tumor Burden / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000276:immunology / Q000378:metabolism
chemical_list: D014408:Biomarkers, Tumor; D014409:Tumor Necrosis Factor-alpha; D042461:Vascular Endothelial Growth Factor A; D009195:Peroxidase; D000118:Acetylglucosaminidase