Alessandro Alves1, Leonardo Diel2, Grasieli Ramos3, Antônio Pinto4, Lisiane Bernardi5, John Yates6, Marcelo Lamers7. 1. School of Dentistry, University Center Univates, Lajeado, RS, Brazil. 2. School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: leocvr@bol.com.br. 3. School of Dentistry, University of Oeste de Santa Catarina, Joaçaba, SC, Brazil. 4. Clayton Foundation Peptide Biology Lab, Salk Institute for Biological Studies, United States. 5. Department of Morphological Sciences, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. 6. Department of Molecular Medicine, The Scripps Research Institute, United States. Electronic address: jyates@scripps.edu. 7. Department of Morphological Sciences, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil. Electronic address: marcelo.lamers@ufrgs.br.
Abstract
OBJECTIVES: To analyze the inflammatory millieu in oral squamous cell carcinoma (OSCC) tumors and the influence of macrophages related-cytokines on the tumor cell migration. MATERIALS AND METHODS: Inflammatory protein profile and macrophage population (M2/M1 ratio) of human OSCC fragments were analyzed by proteomic analysis and flow cytometry assay respectively. To evaluate the effects of inflammation on OSCC behavior, we analyzed the role of polarized macrophages and cytokines (IL-6, IL-1β and TNF-α) on OSCC cell lines (SCC25 and Cal27) responsiveness by western blotting (cell signaling) and time-lapse (cell migration). Also, it was addressed the crosstalk of IL-6-STAT3 axis with cell migration signaling using a STAT3 inhibitor (Stattic®) and a pull down assay for the RhoGTPase Rac1 activity. RESULTS: It was observed a ~2 fold predominance of M2 over M1 macrophages and a pro-inflammatory state in OSCC fragments. The M2 conditioned media increased migration speed and directionality of highly invasive OSCC cells (SCC25). OSCC cell lines were responsive to cytokine stimuli (IL6, IL-1β and TNF-α), but only IL-6 increased migration properties of OSCC cells. This effect was dependent on STAT3-phosphorylation levels, which interfered with Rac1 activation levels. CONCLUSION: Our results suggest that the inflammatory milieu might favor invasion and metastasis of OSCC by the direct effect of macrophage-related cytokines on tumor migration.
OBJECTIVES: To analyze the inflammatory millieu in oral squamous cell carcinoma (OSCC) tumors and the influence of macrophages related-cytokines on the tumor cell migration. MATERIALS AND METHODS: Inflammatory protein profile and macrophage population (M2/M1 ratio) of human OSCC fragments were analyzed by proteomic analysis and flow cytometry assay respectively. To evaluate the effects of inflammation on OSCC behavior, we analyzed the role of polarized macrophages and cytokines (IL-6, IL-1β and TNF-α) on OSCC cell lines (SCC25 and Cal27) responsiveness by western blotting (cell signaling) and time-lapse (cell migration). Also, it was addressed the crosstalk of IL-6-STAT3 axis with cell migration signaling using a STAT3 inhibitor (Stattic®) and a pull down assay for the RhoGTPase Rac1 activity. RESULTS: It was observed a ~2 fold predominance of M2 over M1 macrophages and a pro-inflammatory state in OSCC fragments. The M2 conditioned media increased migration speed and directionality of highly invasive OSCC cells (SCC25). OSCC cell lines were responsive to cytokine stimuli (IL6, IL-1β and TNF-α), but only IL-6 increased migration properties of OSCC cells. This effect was dependent on STAT3-phosphorylation levels, which interfered with Rac1 activation levels. CONCLUSION: Our results suggest that the inflammatory milieu might favor invasion and metastasis of OSCC by the direct effect of macrophage-related cytokines on tumor migration.