Project description:Chronic stimulation of innate immune pathways by microbial agents or damaged tissue is known to promote inflammation-driven tumorigenesis by unclarified mechanisms1-3. Here we demonstrate that mutagenic 7,12-dimethylbenz(a)anthracene (DMBA), etoposide or cisplatin induces nuclear DNA leakage into the cytosol to intrinsically activate STING (Stimulator of Interferon Genes) dependent cytokine production. Inflammatory cytokine levels were subsequently augmented in a STING-dependent extrinsic manner by infiltrating phagocytes purging dying cells. Consequently, STING-/- mice, or wild type mice adoptively transferred with STING-/- bone marrow, were almost completely resistant to DMBA-induced skin carcinogenesis compared to their wild type counterparts. Our data emphasizes, for the first time, a role for STING in the induction of cancer, sheds significant insight into the causes of inflammation-driven carcinogenesis, and may provide therapeutic strategies to help prevent malignant disease Total RNA obtained from DMBA or acetone treated wild type (WT) or STING deficient (SKO) mouse skin or skin tumor was examined for gene expression.
Project description:Chronic stimulation of innate immune pathways by microbial agents or damaged tissue is known to promote inflammation-driven tumorigenesis by unclarified mechanisms1-3. Here we demonstrate that mutagenic 7,12-dimethylbenz(a)anthracene (DMBA), etoposide or cisplatin induces nuclear DNA leakage into the cytosol to intrinsically activate STING (Stimulator of Interferon Genes) dependent cytokine production. Inflammatory cytokine levels were subsequently augmented in a STING-dependent extrinsic manner by infiltrating phagocytes purging dying cells. Consequently, STING-/- mice, or wild type mice adoptively transferred with STING-/- bone marrow, were almost completely resistant to DMBA-induced skin carcinogenesis compared to their wild type counterparts. Our data emphasizes, for the first time, a role for STING in the induction of cancer, sheds significant insight into the causes of inflammation-driven carcinogenesis, and may provide therapeutic strategies to help prevent malignant disease Total RNA obtained from wild type murine embryonic fibroblasts (WT MEFs), STING deficient MEFs (SKO), Trex1 deficient MEFs (TKO), and both STING and Trex1 deficient MEFs (STKO) treated with DMBA and examined cytokine production by these cells.
Project description:Chronic stimulation of innate immune pathways by microbial agents or damaged tissue is known to promote inflammation-driven tumorigenesis by unclarified mechanisms1-3. Here we demonstrate that mutagenic 7,12-dimethylbenz(a)anthracene (DMBA), etoposide or cisplatin induces nuclear DNA leakage into the cytosol to intrinsically activate STING (Stimulator of Interferon Genes) dependent cytokine production. Inflammatory cytokine levels were subsequently augmented in a STING-dependent extrinsic manner by infiltrating phagocytes purging dying cells. Consequently, STING-/- mice, or wild type mice adoptively transferred with STING-/- bone marrow, were almost completely resistant to DMBA-induced skin carcinogenesis compared to their wild type counterparts. Our data emphasizes, for the first time, a role for STING in the induction of cancer, sheds significant insight into the causes of inflammation-driven carcinogenesis, and may provide therapeutic strategies to help prevent malignant disease
Project description:Chronic stimulation of innate immune pathways by microbial agents or damaged tissue is known to promote inflammation-driven tumorigenesis by unclarified mechanisms1-3. Here we demonstrate that mutagenic 7,12-dimethylbenz(a)anthracene (DMBA), etoposide or cisplatin induces nuclear DNA leakage into the cytosol to intrinsically activate STING (Stimulator of Interferon Genes) dependent cytokine production. Inflammatory cytokine levels were subsequently augmented in a STING-dependent extrinsic manner by infiltrating phagocytes purging dying cells. Consequently, STING-/- mice, or wild type mice adoptively transferred with STING-/- bone marrow, were almost completely resistant to DMBA-induced skin carcinogenesis compared to their wild type counterparts. Our data emphasizes, for the first time, a role for STING in the induction of cancer, sheds significant insight into the causes of inflammation-driven carcinogenesis, and may provide therapeutic strategies to help prevent malignant disease
Project description:Chronic stimulation of innate immune pathways by microbial agents or damaged tissue is known to promote inflammation-driven tumorigenesis by mechanisms that are not well understood. Here we demonstrate that mutagenic 7,12-dimethylbenz(a)anthracene (DMBA), cisplatin and etoposide induce nuclear DNA leakage into the cytosol that intrinsically activates stimulator of interferon genes (STING)-dependent cytokine production. Inflammatory cytokine levels are subsequently augmented in a STING-dependent extrinsic manner by infiltrating phagocytes purging dying cells. Consequently, STING(-/-) mice, or wild-type mice adoptively transferred with STING(-/-) bone marrow, are almost completely resistant to DMBA-induced skin carcinogenesis compared with their wild-type counterparts. Our data establish a role for STING in the control of cancer, shed significant insight into the causes of inflammation-driven carcinogenesis and may provide a basis for therapeutic strategies to help prevent malignant disease.
Project description:BRCA1 loss leads to tumor cell transcriptional reprogramming, resulting in a DNA damage-driven, mandatory cell-autonomous type I IFN inflammatory activation mediated by STING and TREX1/2. PARP inhibition augmented this immunoreactivity, creating contextual lethality to dual immune checkpoint blockade (ICB) in vivo. BRCA1-deficient tumor can escape T-cell inflammation through targeted deletion or methylation of the DNA sensing/IFN pathway genes, such as STING, IFNB1 or the chemokine CCL5. Alternatively, BRCA-mutated carcinomas retaining immunoreactivity upregulate their VEGF-A expression driven by STING, which mediates immune resistance and tumor progression. STING elimination attenuated tumor growth and abrogated therapeutic resistance to dual ICB. VEGF-A blockade synergized with immune checkpoint blockade and/or PARP inhibition to control outgrowth of Brca1-/- ovarian tumors, offering opportunities for rational combination therapy of cancers with homologous recombination repair deficiency (HRD).
Project description:Basic studies on preneoplastic lesions are important to determine the molecular alterations that take place in early steps of lung carcinogenesis. Little is known about the molecular events preceding the development of lung cancer in the context of an inflammatory environment. In this study we report the generation of a chemical-induced lung carcinogenesis mouse model in the presence of silicotic chronic inflammation. Silica-induced lung inflammation, strongly promoted incidence of lung cancer in mice treated with NDMA, a carcinogen found in tobacco smoke. Histological and molecular analysis revealed that permanent inflammation contributed to lung tumorigenesis through the adquisition of preneoplastic changes in lung epithelial cells. Inflammatory milieu increased the expression of PDCD1, TGFβ-1, MCP-1, LAG3, and Foxp3 and the presence of regulatory T cells within preneoplastic lesions. In addition concomitant chronic inflammation changed the K-ras mutational profile of the generated tumors from Q61R to G12D transition. In summary, these data identify early molecular mechanisms underlying lung carcinogenesis in an inflammatory context at different steps, providing a novel approach for the identification of drivers from preneoplastic to neoplastic lesions Gene expression profile was analyzed in 11 individual lesions (8 adenomas and 3 adenocarcinomas) from the NDMA-silica treated mice and 5 lesions (2 adenomas, and 3 adenocarcinomas) from NDMA-only treated mice
Project description:A breach in tolerance to self-antigens induces expansion of autoreactive T cells, ultimately leading to autoimmune inflammation. While autoreactive T cells are principal drivers of autoimmunity, tissue pathology is alternatively driven by innate cytokines, indicating that autoreactive T cells can induce innate inflammation. This study has led to the discovery that effector memory T (Tem) cells trigger double stranded breaks via mitochondrial ROS production in interacting DCs. Consequently, initiation of the DNA damage response leads to activation of a cGAS-independent, STING-TRAF6-NFkB signaling axis. STING deficient DCs display significant defects in transcriptional induction and functional production of IL-1b and IL-6 following their interaction with Tem cells, both in vitro and in vivo. The discovery of Tem induced innate inflammation through DNA damage and a non-canonical STING-mediated NFkB activation presents this pathway as a potential target to alleviate T cell driven autoimmune inflammation.