Inflammation has pleiotropic effects on carcinogenesis and tumor progression. Signaling through the adaptor protein MyD88 promotes carcinogenesis in several chemically induced cancer models. Interestingly, we observed a protective role for MyD88 in the development of AOM/DSS colitis-associated cancer. The inability of Myd88-/- mice to heal ulcers generated upon injury creates an inflammatory environment that increases the frequency of mutations and results in a dramatic increase in adenoma formation and cancer progression. Susceptibility to colitis development and enhanced polyp formation were also observed in Il18-/- mice upon AOM/DSS treatment, suggesting that the phenotype of MyD88 knockouts is in part due to their inability to signal through the IL-18 receptor. This study revealed a previously unknown level of complexity surrounding MyD88 activities downstream of different receptors that differentially impact tissue homeostasis and carcinogenesis.
MyD88-mediated signaling prevents development of adenocarcinomas of the colon: role of interleukin 18.
Specimen part, Disease, Disease stage
View SamplesMuscles organise a pseudo-crystalline array of actin, myosin and titin filaments to build force-producing sarcomeres. To study how sarcomeres are built, we performed mRNA-sequencing of developing Drosophila flight muscles and identified 40 distinct expression profile clusters. Strikingly, two clusters are strongly enriched for sarcomeric components. Temporal gene expression together with detailed morphological analysis enabled us to define two distinct phases of sarcomere development, both of which require the transcriptional regulator Spalt major. During the first sarcomere formation phase, 2.0 µm long immature sarcomeres assemble myofibrils that spontaneously contract. In the second sarcomere maturation phase, sarcomeres grow to their final 3.2 µm length and 1.5 µm diameter and acquire stretch-sensitivity. Interestingly, the final number of myofibrils per flight muscle fiber is determined at the onset of the first phase and remains constant. Together, this defines a biphasic mode of sarcomere and myofibril morphogenesis – a new concept which may also apply to vertebrate muscle or heart development. Overall design: Part I: An 8-point timecourse of wild-type flight muscle development in Drosophila melanogaster was analyzed with duplicates/triplicates for each timepoint Part II: A Mef2-Gal4 x salmIR timecourse in duplicate at 4 timepoints was compared to wild-type flight muscle
A transcriptomics resource reveals a transcriptional transition during ordered sarcomere morphogenesis in flight muscle.
Specimen part, Subject
View SamplesThe gut microbiota influences both local and systemic inflammation. Inflammation contributes to development, progression and treatment of cancer, but it remains unclear whether commensal bacteria affect inflammation in the sterile tumor microenvironment. Here we show that disruption of the microbiota impairs the response of subcutaneous tumors to CpG-oligonucleotide immunotherapy and platinum chemotherapy. In antibiotic-treated or germ-free mice, tumor-infiltrating myeloid-derived cells responded poorly to therapy, resulting in lower cytokine production and tumor necrosis after CpG-oligonucleotide treatment, and deficient production of reactive oxygen species and cytotoxicity following chemotherapy. Thus, optimal responses to cancer therapy require an intact commensal microbiota that mediates its effects by modulating myeloid-derived cell functions in the tumor microenvironment. These findings underscore the importance of the microbiota in the outcome of disease treatment.
Commensal bacteria control cancer response to therapy by modulating the tumor microenvironment.
Specimen part
View SamplesExpression data from Breast cancer subtypes
Chronic oxidative stress promotes H2AX protein degradation and enhances chemosensitivity in breast cancer patients.
Disease, Cell line
View SamplesTranscriptome analysis of high-grade human ovarian adenocarcinomas. The hypothesis tested in the present study was that two reciprocal pathways, namely oxidative stress response and fibrosis, enable to build a hierarchical cluster of ovarian patients.
miR-141 and miR-200a act on ovarian tumorigenesis by controlling oxidative stress response.
Specimen part, Disease stage
View SamplesCaspases, proteolytic enzymes involved in cell death could play a role independent of cell death in the developing heart
Executioner Caspase-3 and 7 Deficiency Reduces Myocyte Number in the Developing Mouse Heart.
Age, Specimen part
View SamplesIn a cohort study of 7 women with primary invasive breast cancer, we obtained a tumor specimen before (biopsy) and after (tumorectomy) 4 cycles of NAC with epirubicine and cyclophosphamide, followed by 4 cycles of taxanes. Total RNA was extracted from tumor specimens and the whole transcriptome was quantified with Affymetrix HuGene1.1ST. Molecular functions changing during chemotherapy were searched.
Chronic oxidative stress promotes H2AX protein degradation and enhances chemosensitivity in breast cancer patients.
Specimen part, Subject, Time
View Samples10 biopsies before treatment from triple negative patients with complete response were collected. Total RNA was extracted from tumor specimens and the whole transcriptome was quantified with Affymetrix HuGene1.1ST. The biopsies were classified into Good (major or complete) or Poor (absent or minor) therapeutic response subgroup.
Chronic oxidative stress promotes H2AX protein degradation and enhances chemosensitivity in breast cancer patients.
Sex, Specimen part
View SamplesDiffuse intrinsic pontine glioma (DIPG) is an incurable pediatric brain tumor, resulting in the death of 200-300 children each year in the United States. Recently it was discovered that approximately 25% of all DIPG cases harbor activating mutations in ACVR1, a gene that encodes Activin A receptor (ALK2), a receptor in the bone morphogenetic protein (BMP) pathway, and that DIPGs with ALK2 mutations commonly harbor an H3.1K27M mutation. Herein, we used the RCAS/TVA retroviral system to study the effects of ACVR1 mutations and H3.1K27M on DIPG pathogenesis. In vitro expression of R206H ACVR1 with and without H3.1K27M in nestin-expressing brainstem progenitors resulted in upregulation of mesenchymal markers and gene set enrichment analysis (GSEA) revealed Stat3 pathway activation. Neonatal expression of ACVR1 R206H or G328V in combination with H3.1K27M and p53 deletion in nestin-expressing brainstem progenitors induced glioma-like lesions expressing mesenchymal markers with Stat3 activation but was not sufficient for full gliomagenesis. In combination with platelet-derived growth factor A (PDGFA) signaling, ACVR1 R206H and H3.1K27M significantly decreased survival and increased tumor incidence. We demonstrate that targeting the BMP signaling pathway may be an effective therapeutic strategy to treat ACVR1 R206H mutant DIPGs. Exogenous Noggin expression at tumor initiation significantly increased tumor latency and treatment of ACVR1 R206H mutant murine DIPGs with LDN212854, an ACVR1 inhibitor, significantly prolonged their survival. We confirm relevance of our model to the human disease as human DIPG models with ACVR1 mutations were also sensitive to treatment with LDN212854 in vitro. Altogether, our studies demonstrate that ACVR1 R206H and H3.1K27M promote tumor initiation, accelerate gliomagenesis, promote a mesenchymal profile in part due to Stat3 activation, and identify LDN212854 as a promising compound to treat children with DIPG. Overall design: We use RNAseq to study the transcriptomal effects of ACVR1 WT or R206H ACVR1 mutation alone and in combination with H3.1K27M mutation on murine nestin-expressing brainstem progenitors at P3-5 (using RCAS/TVA). Key findings were validated by Real-Time PCR.
ACVR1 R206H cooperates with H3.1K27M in promoting diffuse intrinsic pontine glioma pathogenesis.
Specimen part, Subject
View SamplesTumor cells exhibit aberrant metabolism characterized by high glycolysis even in the presence of oxygen. This metabolic reprogramming, known as the Warburg effect, provides tumor cells with the substrates and redox potential required for the generation of biomass. Here, we show that the mitochondrial NAD-dependent deacetylase SIRT3 is a crucial regulator of the Warburg effect. SIRT3 loss promotes a metabolic profile consistent with high glycolysis required for anabolic processes in vivo and in vitro. Mechanistically, SIRT3 mediates metabolic reprogramming independently of mitochondrial oxidative metabolism and through HIF1a, a transcription factor that controls expression of key glycolytic enzymes. SIRT3 loss increases reactive oxygen species production, resulting in enhanced HIF1a stabilization. Strikingly, SIRT3 is deleted in 40% of human breast cancers, and its loss correlates with the upregulation of HIF1a target genes. Finally, we find that SIRT3 overexpression directly represses the Warburg effect in breast cancer cells. In sum, we identify SIRT3 as a regulator of HIF1a and a suppressor of the Warburg effect.
SIRT3 opposes reprogramming of cancer cell metabolism through HIF1α destabilization.
Specimen part
View Samples