Luciana Y de Almeida1, Flávia S Mariano1, Débora C Bastos1, Karen A Cavassani2, Janna Raphelson2, Vânia S Mariano3, Michelle Agostini4, Fernanda S Moreira1, Ricardo D Coletta1, Renata O Mattos-Graner1, Edgard Graner5. 1. Department of Oral Diagnosis, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil. Av. Limeira 901, CP 52, Areão, Piracicaba, SP, 13414-903, Brazil. 2. Urologic Oncology Program/Uro-Oncology Research Laboratories, Cedars-Sinai Medical Center, Samuel Oschin Comprehensive Cancer Institute, Los Angeles, CA, 90048, USA. 3. Department of Basic and Applied Immunology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil. 4. Department of Oral Diagnosis and Pathology, School of Dentistry, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil. 5. Department of Oral Diagnosis, School of Dentistry of Piracicaba, State University of Campinas (UNICAMP), Piracicaba, São Paulo, Brazil. Av. Limeira 901, CP 52, Areão, Piracicaba, SP, 13414-903, Brazil. graner@unicamp.br.
Abstract
PURPOSE: Fatty acid synthase (FASN), the multifunctional enzyme responsible for endogenous fatty acid synthesis, is highly expressed and associated with poor prognosis in several human cancers, including melanoma. Our group has previously shown that pharmacological inhibition of FASN with orlistat decreases proliferation, promotes apoptosis, and reduces the metastatic spread of B16-F10 cells in experimental models of melanoma. While most of the orlistat antitumor properties seem to be closely related to direct effects on malignant cells, its impact on the host immune system is still unknown. METHODS: The effects of orlistat on the phenotype and activation status of infiltrating leukocytes in primary tumors and metastatic lymph nodes were assessed using a model of spontaneous melanoma metastasis (B16-F10 cells/C57BL/6 mice). Cells from the primary tumors and lymph nodes were mechanically dissociated and immune cells phenotyped by flow cytometry. The expression of IL-12p35, IL-12p40, and inducible nitric oxide synthase (iNOS) was analyzed by qRT-PCR and production of nitrite (NO2-) evaluated in serum samples with the Griess method. RESULTS: Orlistat-treated mice exhibited a 25% reduction in the number of mediastinal lymph node metastases (mean 3.96 ± 0.78, 95% CI 3.63-4.28) compared to the controls (mean 5.7 ± 1.72; 95% CI 5.01-6.43). The drug elicited an antitumor immune response against experimental melanomas by increasing maturation of intratumoral dendritic cells (DC), stimulating the expression of cytotoxicity markers in CD8 T lymphocytes and natural killer (NK) cells, as well as reducing regulatory T cells (Tregs). Moreover, the orlistat-treatment increased serum levels of nitric oxide (NO) concentrations. CONCLUSION: Taken together, these findings suggest that orlistat supports an antitumor response against experimental melanomas by increasing CD80/CD81-positive and IL-12-positive DC populations, granzyme b/NKG2D-positive NK populations, and perforin/granzyme b-positive CD8 T lymphocytes as well as reducing Tregs counts within experimental melanomas.
PURPOSE: Fatty acid synthase (FASN), the multifunctional enzyme responsible for endogenous fatty acid synthesis, is highly expressed and associated with poor prognosis in several human cancers, including melanoma. Our group has previously shown that pharmacological inhibition of FASN with orlistat decreases proliferation, promotes apoptosis, and reduces the metastatic spread of B16-F10 cells in experimental models of melanoma. While most of the orlistat antitumor properties seem to be closely related to direct effects on malignant cells, its impact on the host immune system is still unknown. METHODS: The effects of orlistat on the phenotype and activation status of infiltrating leukocytes in primary tumors and metastatic lymph nodes were assessed using a model of spontaneous melanoma metastasis (B16-F10 cells/C57BL/6 mice). Cells from the primary tumors and lymph nodes were mechanically dissociated and immune cells phenotyped by flow cytometry. The expression of IL-12p35, IL-12p40, and inducible nitric oxide synthase (iNOS) was analyzed by qRT-PCR and production of nitrite (NO2-) evaluated in serum samples with the Griess method. RESULTS: Orlistat-treated mice exhibited a 25% reduction in the number of mediastinal lymph node metastases (mean 3.96 ± 0.78, 95% CI 3.63-4.28) compared to the controls (mean 5.7 ± 1.72; 95% CI 5.01-6.43). The drug elicited an antitumor immune response against experimental melanomas by increasing maturation of intratumoral dendritic cells (DC), stimulating the expression of cytotoxicity markers in CD8 T lymphocytes and natural killer (NK) cells, as well as reducing regulatory T cells (Tregs). Moreover, the orlistat-treatment increased serum levels of nitric oxide (NO) concentrations. CONCLUSION: Taken together, these findings suggest that orlistat supports an antitumor response against experimental melanomas by increasing CD80/CD81-positive and IL-12-positive DC populations, granzyme b/NKG2D-positive NK populations, and perforin/granzyme b-positive CD8 T lymphocytes as well as reducing Tregs counts within experimental melanomas.
Authors: B A B de Andrade; J E León; R Carlos; W Delgado-Azañero; A Mosqueda-Taylor; E Graner; O P de Almeida Journal: Oral Dis Date: 2011-08-08 Impact factor: 3.511
Authors: P R Pandey; F Xing; S Sharma; M Watabe; S K Pai; M Iiizumi-Gairani; K Fukuda; S Hirota; Y-Y Mo; K Watabe Journal: Oncogene Date: 2012-12-03 Impact factor: 9.867