Thirty-eight tumors from 17 patients treated with BRAF inhibitor (n=12) or combination BRAF/MEK inhibitors (n=5) with known PD-L1 expression were analyzed. RNA expression arrays were performed on all pre-treatment (PRE, n=17), early during treatment (EDT, n=8) and progression (PROG, n=13) biopsies. HLA-A/HLA-DPB1 expression was assessed by immunohistochemistry (IHC). Gene set enrichment analysis (GSEA) of PRE, EDT and PROG melanomas revealed that transcriptome signatures indicative of immune cell activation were strongly positively correlated with PD-L1 staining. In contrast, MAPK signaling and canonical Wnt/--catenin activity were negatively associated with PD-L1 melanoma expression. The expression of PD-L1 and immune activation signatures did not simply reflect the degree or type of immune cell infiltration, and was not sufficient for tumor response to MAPK inhibition.
PD-L1 Expression and Immune Escape in Melanoma Resistance to MAPK Inhibitors.
Specimen part
View SamplesCutaneous, acral and mucosal subtypes of melanoma were evaluated by whole-genome sequencing, revealing genes affected by novel recurrent mutations to the promoter (TERT, DPH3, OXNAD1, RPL13A, RALY, RPL18A, AP2A1), 5-UTR (HNRNPUL1, CCDC77, PES1), and 3-UTR (DYNAP, CHIT1, FUT9, CCDC141, CDH9, PTPRT) regions. TERT promoter mutations had the highest frequency of any mutation, but neither they nor ATRX mutations, associated with the alternative telomere lengthening mechanism, were correlated with greater telomere length. Genomic landscapes largely reflected ultraviolet radiation mutagenesis in cutaneous melanoma and provided novel insights into melanoma pathogenesis. In contrast, acral and mucosal melanomas exhibited predominantly structural changes, and mutation signatures of unknown aetiology not previously identified in melanoma. The majority of melanomas had potentially actionable mutations, most of which were in components of the mitogen-activated protein kinase and phosphoinositol kinase pathways.
Whole-genome landscapes of major melanoma subtypes.
No sample metadata fields
View SamplesPurpose: The purpose of this experiment is to expand the repertoire of C. elegans edited transcripts and identify the roles of ADR-1 as indirect regulator of editing and ADR-2 as the only active deaminase in vivo. Methods: Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline. Results: Despite lacking deaminase function, ADR-1 affects editing of over 60 adenosines within the 3’ UTRs of 16 different mRNAs. Furthermore, ADR-1 interacts directly with ADR-2 substrates, even in the absence of ADR-2; and mutations within its dsRNA binding domains abolished both binding and editing regulation. Conclusions: ADR-1 acts as a major regulator of editing by binding ADR-2 substrates in vivo and raises the possibility that other dsRNA binding proteins, including the inactive human ADARs, regulate RNA editing by deaminase-independent mechanisms. Overall design: Strand-specific RNA sequencing of wild-type and adr mutant worms, followed by a novel RNA variant calling and comparative analysis pipeline.
The dsRBP and inactive editor ADR-1 utilizes dsRNA binding to regulate A-to-I RNA editing across the C. elegans transcriptome.
Specimen part, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Runx2 is required for early stages of endochondral bone formation but delays final stages of bone repair in Axin2-deficient mice.
Sex
View SamplesRunx2 and Axin2 regulate skeletal development. We recently determined that Axin2 and Runx2 molecularly interact in differentiating osteoblasts to regulate intramembranous bone formation, but the relationship between these factors in endochondral bone formation was unresolved. To address this, we examined the effects of Axin2 deficiency on the cleidocranial dysplasia (CCD) phenotype of Runx2+/-mice, focusing on skeletal defects attributed to improper endochondral bone formation. Axin2 deficiency unexpectedly exacerbated calvarial components of the CCD phenotype in the Runx2+/-mice; the endocranial layer of the frontal suture, which develops by endochondral bone formation, failed to mineralize in the Axin2-/-:Runx2+/-mice, resulting in a cartilaginous, fibrotic and larger fontanel than observed in Runx2+/-mice. Transcripts associated with cartilage development (e.g., Acan, miR140) were expressed at higher levels, whereas blood vessel morphogenesis transcripts (e.g., Slit2) were suppressed in Axin2-/-:Runx2+/-calvaria. Cartilage maturation was impaired, as primary chondrocytes from double mutant mice demonstrated delayed differentiation and produced less calcified matrix in vitro. The genetic dominance of Runx2 was also reflected during endochondral fracture repair, as both Runx2+/-and double mutant Axin2-/-:Runx2+/-mice had enlarged fracture calluses at early stages of healing. However, by the end stages of fracture healing, double mutant animals diverged from the Runx2+/-mice, showing smaller calluses and increased torsional strength indicative of more rapid end stage bone formation as seen in the Axin2-/-mice. Taken together, our data demonstrate a dominant role for Runx2 in chondrocyte maturation, but implicate Axin2 as an important modulator of the terminal stages of endochondral bone formation.
Runx2 is required for early stages of endochondral bone formation but delays final stages of bone repair in Axin2-deficient mice.
Sex
View SamplesIn chronic lymphocytic leukemia (CLL), 13q14 and 11q22-23 deletions are found in 2/3 of the cases. 11q22-23 deletions are associated with poor survival, whereas 13q14 deletions as single abnormality are often found in indolent disease forms. The molecular basis for this difference in prognosis is not known.
Expression analysis of genes located in the minimally deleted regions of 13q14 and 11q22-23 in chronic lymphocytic leukemia-unexpected expression pattern of the RHO GTPase activator ARHGAP20.
Specimen part, Disease, Disease stage
View SamplesDespite education and aggressive treatment, breast cancer (BC) remains a clinical problem. BC cells (BCCs) can migrate early to metastatic sites where they may exist in cellular dormancy for decades. Presently, there are no consensus markers for cancer stem cells (CSCs) that are involved in tumor initiation and progression, and drug resistance. The current designation of CSCs might comprise similar tumor initiating cells, but at different developmental phase. In order to understand these differences, we developed a working hierarchy of BCCs. We initiated the studies in which three BCC subsets were selected based on the relative expressions of the stem cell-linked genes, Octamer4A (Oct4A). The sorted BCCs were subjected to array analyses using Affymetrix gene chip. Hierarchical clustering indicated distinct gene expression among the three subsets. Differential gene expressions of membrane proteins validated three novel genes, TMEM-98, GPR64 and FAT4. These three genes, in combination of known markers for CSCs, CD44, CD24, aldehyde dehydrogenase 1 (ALDH1) and Oct4A, were used to stratify BCCs led to a working hierarchy of BCCs. The validity of the hierarchical BCCs was applied to blood samples from patients, during relapse, and before and after treatment. These studies resulted in the patients grouped with distinct BCCs in the circulation. The relevance of the latter findings are discussed with regards to prediction of treatment response and time of BC relapse. The findings require a larger cohort of patients in a prospective multi-center study. The stratification could be important to understand treatment response, strategies for alternative approaches, and an understanding of the interaction between particular BCC subsets and the tissue microenvironment.
Evaluation of a developmental hierarchy for breast cancer cells to assess risk-based patient selection for targeted treatment.
Specimen part, Cell line
View Samples7-days-old Arabidopsis seedlings of wildtype (Col-0) were treated with 1 M IAA for 15 minutes or 3 hours and gene expression of whole plant was analyzed using Affymetrix Gene 1.1 ST Array strips.
AtCAST3.0 update: a web-based tool for analysis of transcriptome data by searching similarities in gene expression profiles.
Age, Treatment, Time
View SamplesChronic lymphocytic leukemia (CLL) is a common and heterogeneous disease. An accurate prediction of outcome is highly relevant for the development of personalized treatment strategies. Microarray technology was shown to be a useful tool for the development of prognostic gene expression scores. However, there are no gene expression scores which are able to predict overall survival in CLL based on the expression of few genes that are better than established prognostic markers. We correlated 151 CLL microarray data sets with overall survival using Cox regression and supervised principal component analysis to derive a prognostic score. This score based on the expression levels of eight genes and was validated in an independent group of 149 CLL patients by quantitative real time PCR. The score was predictive for overall survival and time to treatment in univariate Cox regression in the validation data set (both: p<0.001) and in a multivariate analysis after adjustment for 17p and 11q deletions and the IgVH-status. The score achieved superior prognostic accuracy compared to models based on genomic aberrations and IgVH-status and may support personalized therapy.
An eight-gene expression signature for the prediction of survival and time to treatment in chronic lymphocytic leukemia.
Specimen part, Disease, Disease stage
View SamplesSIRT3 is a mitochondrial NAD(+)-dependent protein deacetylase, which regulates the enzymatic activity of several mitochondrial proteins.
SIRT3 deficiency and mitochondrial protein hyperacetylation accelerate the development of the metabolic syndrome.
Age, Specimen part
View Samples