Spontaneous tumor regression is driven by Wnt/Retinoic Acid signaling cross-talk
ABSTRACT: We have identified by RNA sequencing the molecular signaling pathways that are involved in skin tumor regression and that fail to happen in malignant not regressing skin tumors . mRNA profile from Keratoacanthoma tumors at 0 and 1 week post DMBA treatment was generated in duplicate for each timepoint analyzed
Project description:Germline polymorphisms influence gene expression networks in normal mammalian tissues. Analysis of this genetic architecture can identify single genes and whole pathways that influence to complex traits including inflammation and cancer susceptibility. Changes in the genetic architecture during the development of benign and malignant tumours have not been investigated. Here, we document major changes in germline control of gene expression during skin tumour development as a consequence of cell selection, somatic genetic events, and changes in tumour microenvironment. Immune response genes such as Interleukin 18 and Granzyme E are under germline control in tumours but not in normal skin. Gene expression networks linked to tumour susceptibility and hair follicle stem cell markers in normal skin undergo significant reorganization during tumour progression. Our data highlight opposing roles of Interleukin-1 signaling networks in tumour susceptibility and tumour progression and have implications for the development of chemopreventive strategies to reduce cancer incidence. Skin tumors were induced on dorsal back skin from a Mus spretus / Mus musculus backcross ([SPRET/Ei X FVB/N] X FVB/N) mice by treatment of dorsal back skin with dimethyl benzanthracene (DMBA) and tetradecanoyl-phorbol acetate (TPA). This treatment induced multiple benign papillomas as well as malignant squamous cell carcinomas (SCC) and spindle cell carcinomas. Gene expression analysis was performed on mRNA extracted from 68 papillomas: two papillomas from each of 31 FVBBX mice and a single papilloma from six additional FVBBX mice. Papillomas were harvested when mice were sacrificed due to presence of a carcinoma or termination of the experiment.
Project description:Background: Germline polymorphisms can influence gene expression networks in normal mammalian tissues and can affect disease susceptibility. We and others have shown that analysis of this genetic architecture can identify single genes and whole pathways that influence complex traits including inflammation and cancer susceptibility. Whether germline variants affect gene expression in tumors which have undergone somatic alterations, and the extent to which these variants influence tumor progression, is unknown. Results: Using an integrated linkage and genomic analysis of a mouse model of skin cancer that produces both benign tumors and malignant carcinomas, we document major changes in germline control of gene expression during skin tumor development resulting from cell selection, somatic genetic events, and changes in the tumor microenvironment. The number of significant expression Quantitative Trait Loci (eQTLs) is progressively reduced in benign and malignant skin tumors when compared to normal skin. However, novel tumor-specific eQTLs are detected for several genes associated with tumor susceptibility, including Interleukin 18, Granzyme E, Sprouty homolog 2, and MAP kinase kinase 4. Conclusions: We conclude that the genetic architecture is substantially altered in tumors, and that eQTL analysis of tumors can identify host factors that influence the tumor microenvironment, MAP kinase signaling, and cancer susceptibility. A backcross was generated using male Mus spretus and female FVB/N mice; female F1 hybrids were mated with male FVB/N mice. Backcross mice (8-12 weeks old) received a single dose of DMBA (25 µg per mouse in 200 µl acetone). Starting one week after the initiation tumors were promoted with TPA (200 µl of 10-4 M solution in acetone) twice weekly for 20 weeks. Initiation and promotion were performed on doral back skin. DNA from 62 Carcinomas and matched untreated tails (used for normal DNA comparison) was obtained from tissue that was snap frozen when animals were sacrificed.
Project description:Blood (mRNA and miRNA) and skin mRNA transcriptomes were investigated across three time-points in a pilot investigation of ten severe psoriasis patients, treated with the tumor necrosis factor (TNF) inhibitor, etanercept. We used illumina RNA-sequencing to analyse the small-RNA transcriptome in blood
Project description:Blood (mRNA and miRNA) and skin mRNA transcriptomes were investigated across three time-points in a pilot investigation of ten severe psoriasis patients, treated with the tumor necrosis factor (TNF) inhibitor, etanercept. We used illumina RNA-sequencing to analyse the mRNA transcriptome in blood
Project description:Langerhans cells (LCs) populate the mucosal epithelium, a major entry portal for pathogens, yet their ontogeny remains unclear. In contrast to skin LCs originating from self-renewing radioresistant embryonic precursors, we found that oral mucosal LCs derive from circulating radiosensitive precursors. Mucosal LCs can be segregated into CD103+CD11blow (CD103+LCs) and CD11b+CD103- (CD11b+LCs) subsets. We further demonstrated that similar to non-lymphoid dendritic cells (DCs), CD103+LCs originate from pre-DCs, whereas CD11b+LCs differentiate from both pre-DCs and monocytic precursors. Despite this ontogenetic discrepancy between skin and mucosal LCs, transcriptomic signature and immunological function of oral LCs highly resemble those of skin LCs but not DCs. These findings, along with their epithelial position, morphology and expression of LC-associated phenotype strongly suggest that oral mucosal LCs are genuine LCs. Collectively, in a tissue-dependent manner, murine LCs differentiate from at least three distinct precursors (embryonic, pre-DCs and monocytic) in steady state The following cells were isolated from mice (2-4 replicates): Lung DCs, mucosal CD103+ LC, mucosal CD11b+ LC, Skin LC. Transcriptome analysis was performed.
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:We have identified by RNA sequencing the molecular signaling pathways that are involved in skin tumor regression and that fail to happen in malignant not regressing skin tumors . Overall design: mRNA profile from Keratoacanthoma tumors at 0 and 1 week post DMBA treatment was generated in duplicate for each timepoint analyzed
Project description:We used Illumina Small RNA and RNA-Seq kits to prepare both small RNA and RNA-Seq libraries from total RNA isolated from either leptotenze/zygotene or pachytene spermatocytes purified from either Dgcr8 or Dicer germline conditional knockout mice. Conditional knockout mice were generated by using a Ddx4 promoter to drive cre excision of either Dgcr8 or Dicer at embryonic day 18. Mixed leptotene/zygotene or pachytene spermatocytes were then isolated from the testis of adult conditional knockout mice, along with paired WT littermates as a control. RNA was isolated from these spermatocytes using Trizol. Small RNA or RNA-Seq libraries were then prepped using Illumina's sequencing library preparation kits.