14662 results for "PLOS+ONE+Pennsylvania+German+ACS+language+code+pdc+open+access+study"

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• High-coverage whole-genome sequencing reveals structural variations in triple-negative breast cancer

  Triple-negative breast cancer (TNBC) cells do not express estrogen receptors, progesterone receptors or human epidermal growth factor receptor 2 (HER2). Currently, apart from poly ADP-ribose polymerase (PARP) inhibitors, there are few effective therapeutic options for this cancer type. Here, we present a comprehensive characterization of genetic alterations in TNBC via high-coverage whole-genome sequencing along with transcriptomic and whole-exome sequencing. Silencing of BRCA1 gene impaired the homologous recombination (HR) pathway in a subset of TNBC, which exhibited similar phenotypes with tumors with BRCA1 mutations; they harbored many structural variations (SVs) with relative enrichment for tandem duplication. Clonal analysis suggested that TP53 mutations and methylation of CpG dinucleotides in the BRCA1 promoter were the early events of carcinogenesis. SVs were associated with driver oncogenic events such as amplification of MYC, NOTCH2 or NOTCH3 and impacted tumor suppressor genes including RB1, PTEN and KMT2C. We also identified a variety of oncogenes that could transform 3T3 mouse fibroblast cells, suggesting that individual TNBC tumors may undergo a unique driver event that can be targetable. Thus, we revealed several features of TNBC that had important clinical implications.

  Study JGAS000095

• Non-small cell lung cancer molecular subtypes and vulnerability to immunotherapy treatment combinations

  The phase 3 IMpower150 trial in treatment-naïve patients with metastatic non-small-cell lung cancer (NSCLC) demonstrated significantly longer progression-free (PFS) and overall survival (OS) with first-line atezolizumab (anti-PD-L1)-bevacizumab (anti-VEGF)-carboplatin-paclitaxel (ABCP) than with bevacizumab-carboplatin-paclitaxel (BCP). We characterised four molecular NSCLC subtypes identified by unsupervised clustering of transcriptomes of 564 pre-treatment primary tumour samples from IMpower150 using non-negative matrix factorization (NMF1-4). Each subtype had distinct tumour PD-L1 expression levels, epithelial characteristics, immune composition, and treatment outcomes. Both NMF2 (enriched in tumour proliferation signal, macrophages, and monocytes) and NMF4 (enriched in B-cells and T cells) had elevated tumour PD-L1 expression. Of these two, only NMF4 demonstrated PFS and OS benefits with ABCP versus either BCP or atezolizumab-carboplatin-paclitaxel (ACP). Patients with NMF1 (enriched in basal and squamous-like cells) had improved outcomes on ABCP compared with ACP or BCP; those with NMF3 (enriched in adenocarcinoma signatures) showed similar outcomes among treatments. These insights could help inform individualised first-line treatment for metastatic NSCLC.

  Study EGAS50000001272

• Dynamics of checkpoint receptors in γδ T cell subsets are associated with clinical responses during anti-PD-1 immunotherapies

  Gamma delta (γδ) T cells are innate-like lymphocytes with potent anti-tumor properties. Herein, we show that immune checkpoint receptors (ICRs) display differential expression and regulation by the JAK-STAT pathway in Vδ1 and Vδ2 cells and identify constitutive (e.g. TIGIT, PD-1) and inducible (e.g. TIM-3, LAG-3, CTLA-4) ICRs. In melanoma, all γδ T cell subsets downregulated AP-1 transcription factors, but Vδ1 cells specifically expressed high levels of ICR, TOX and inhibitory killer Ig-like receptor (KIR) transcripts, reminiscent of exhaustion. However, patient-derived cells were functionally competent, although induction of LAG-3 and CTLA-4 was impaired. During anti-PD-1 monotherapy, Vδ1 cells specifically bound high levels of therapeutic antibody but only in patients who responded to treatment, revealing a potential new prognostic marker for evaluating the efficacy of IC blockade (ICB) therapy. Finally, expression of KIR genes in Vδ1 cells was downregulated in response to successful ICB therapy. Collectively, our data indicate an intricate relationship between ICRs and γδ T cells and reveal novel approaches by which these cells can be harnessed in order to discern or improve cancer immunotherapy.

  Study EGAS50000001270

• FLT3-targeting and places FLT3 as an ideal therapeutic target to selectively eradicate LSCs, while sparing HSC.

  CRISPR/Cas9 FLT3 knock-out (FLT3-KO) in human HSCs and LSCs followed by functional xenograft assays to test their ability to regenerate human hematopoiesis and leukemia, respectively. FLT3-KO in HSCs from human fetal liver, cord blood and adult bone marrow showed no impairment in multilineage hematopoiesis in primary and secondary xenografts. By contrast, FLT3-KO LSCs from 6 of 7 FLT3-ITD mutated AMLs were able to generate short-term engraftment but were completely exhausted by 12 weeks. Thus, FLT3 is essential for LSC long-term propagation. This dependency was unique to FLT3-ITD AML samples as non-FLT3-ITD AML samples generated leukemic grafts upon FLT3-KO. Transcriptomic analysis revealed that FLT3-KO induced downregulation of DNA repair and cell cycle checkpoints, uniquely in FLT3-ITD AML, but not in healthy HSCs or other AMLs. Our research highlights a critical distinction between healthy HSCs and LSCs: whereas healthy hematopoiesis proceeds unperturbed upon FLT3-KO, FLT3-ITD leukemogenesis is impaired through elimination of LSCs. This evidence underscores the necessity for more potent FLT3-targeting and places FLT3 as an ideal therapeutic target to selectively eradicate LSCs, while sparing HSC.

  Study EGAS50000000437

• Context-specific regulatory genetic variation in MTOR dampens neutrophil-T cell crosstalk in pneumonia-associated sepsis, modulating disease

  Sepsis is a heterogeneous clinical syndrome with a high mortality, requiring personalised stratification strategies. Here, we characterise genetic variation that modulates MTOR, a critical regulator of metabolism and immune responses in sepsis. The effects are highly context specific, involving a regulatory element that affects MTOR expression in activated T cells with opposite direction of effect in neutrophils. We show that the G-allele of the lead variant, rs4845987, associated with decreased risk of T2D, reduces MTOR expression in T cells and improves survival in sepsis due to pneumonia, with effects specific to sepsis endotype. Using ex vivo models, we demonstrate that activated T cells promote immunosuppressive sepsis neutrophils through released cytokines, a process dampened by hypoxia and the mTOR inhibitor rapamycin. Our work demonstrates a novel epigenetic mechanism that fine-tunes MTOR transcription and T cell activity via the variant-containing regulatory element, which further exhibits an allelic effect upon vitamin C treatment. These findings reveal how genetic variation interacts with disease state to modulate immune cell-cell communication, providing a patient stratification strategy to inform more effective sepsis treatment.

  Study EGAS50000000894

• Non-canonical NF-κB signaling skews B cells away from germinal center to low-affinity effector fate

  The non-canonical (NC) NF-κB pathway is a central regulator of B-cell development and survival, yet its role during B-cell mediated adaptive responses remains uncharted. Here, we uncover an unanticipated regulatory function for NC NF-κB in shaping humoral immunity. High-resolution mapping of NC NF-kB status in B cells from human lymphoid tissues revealed low activity in germinal center B-cells (GCB) than effector subsets, suggesting a selective attenuation. Consistently, mice model harboring B-cells with enforced NC NF-κB activation revealed near- complete loss of GCB and high-affinity antibodies, following vaccination. GCB loss was not driven by intrinsic defects in formation or expansion, but by an immune-niche dysregulation marked by regulatory T-cell expansion. Mechanistically, NC NF-κB activation promoted B-cell- derived IL-10, and blocking this axis normalize the niche and rescue GCB. Concurrently, NC NF- κB signaling boosted low-affinity antibody responses by transcriptionally priming follicular B- cells for plasmacytic differentiation. Together, these findings position NC NF-κB as a tunable rheostat linking B-cell signaling to immune-niche control and humoral immunity.

  Study EGAS50000001646

• UK10K_OBESITY_GS

  In the UK10K project we propose a series of complementary genetic approaches to find new low frequency/rare variants contributing to disease phenotypes. These will be based on obtaining the genome wide sequence of 4000 samples from the TwinsUK and ALSPAC cohorts (at 6x sequence coverage), and the exome sequence (protein coding regions and related conserved sequence) of 6000 samples selected for extreme phenotypes. Our studies will focus primarily on cardiovascular-related quantitative traits, obesity and related metabolic traits, neurodevelopmental disorders and a limited number of extreme clinical phenotypes that will provide proof-of-concept for future familial trait sequencing. We will analyse directly quantitative traits in the cohorts and the selected traits in the extreme samples, and also use imputation down to 0.1% allele frequency to extend the analyses to further sample sets with genome wide genotype data. In each case we will investigate indels and larger structural variants as well as SNPs, and use statistical methods that combine rare variants in a locus or pathway as well as single-variant approaches. The GS samples are part of the Obesity group and will undergo exome sequencing.

  Study EGAS00001000242

• Genomic analysis of Smoothened inhibitor resistance in basal cell carcinoma

  Smoothened inhibitors are currently being investigated for the treatment of several cancers. Vismodegib is approved for the treatment of locally advanced and metastatic basal cell carcinoma (BCC). The majority of BCC patients treated with vismodegib experience significant clinical benefit, however, a small number of patients develop resistance. Knowledge of resistance mechanisms can generate predictive biomarkers and is critical for the design of additional therapeutic strategies aimed at circumventing resistance. To investigate mechanisms of resistance to vismodegib in BCC we sequenced and profiled biopsies from patients who initially responded to treatment and subsequently progressed on drug.We find that resistance is associated with re-activation of the Hedgehog (Hh) pathway through diverse mechanisms, including concurrent copy number alterations in the downstream Hh pathway components SUFU and GLI2, as well as novel SMO mutations that reduce sensitivity to vismodegib. The latter fall into two classes: those that activate SMO and those that directly affect the vismodegib-binding pocket. Additionally, we observe evidence of clonal selection of SMO mutations and intra-tumor heterogeneity of resistance mechanisms, which implies diverse and combinatorial strategies are required to overcome resistance.

  Study EGAS00001000845

• Distinct portrayal of lesions in synchronous multifocal lung adenocarcinoma revealed by genome sequencing

  Distinguishing multiple primary lung cancers in the synchronous multifocal intrapulmonary lesions has important significance on clinical staging and therapeutic decision. To investigate genomic aberration profiles, we applied whole genome and whole exome sequencing, and microarray-based comparative genomic hybridization on 15 intrapulmonary tumors derived from six patients with synchronous multifocal lung cancers having similar histological diagnosis. Any pair of intrapulmonary tumors in a single patient, which shared the identical genetic background and environment, showed an extinctive heterogeneity between each other. Phylogenetic relationship analysis indicated an independently branched evolution among all the tumors, suggesting they were multiple primary lung cancers. EGFR or KRAS mutations were found in 7 or 3 out of the 15 tumors, from 3 or 2 patients, respectively. Somatic mutational heterogeneity of these two genes in a single patient was also observed. Our analysis indicates genomic aberration profiling is valuable for identification of multiple primary lung cancer, especially when high histopathological concordance was observed between lesions. We also suggest a thoroughly molecular diagnosis against therapeutic target genes should be taken for each accessible nodule before making a plan for adjuvant therapy.

  Study EGAS00001001572

• Dissection of the molecular complexity of colorectal cancer in pre-clinical models identifies predictive signatures of sensitivity to EGFR inhibitors

  Colorectal carcinoma (CRC) is a heterogeneous tumour entity, with only a fraction of the tumours responding to currently available therapies. A detailed understanding of the biology and genetics of CRC is a prerequisite for precision medicine. To address this challenge in clinical oncology, the OncoTrack consortium recruited 106 CRC patients (stages I-IV) and developed an integrated pre-clinical platform analysing drug sensitivity in the established matched patient-derived in vivo and in vitro models, 46 three-dimensional cell cultures and 59 xenografts, recapitulating many of the molecular features of the donor tumours. We generated extensive omics information on patient tumours and their derived models used to generate a compendium of drug sensitivity data. We could distinguish tumour molecular sub-groups responding differently to therapy and identified a novel independent predictor of sensitivity to the EGFR inhibitor cetuximab. The findings reported here will advance our understanding of CRC and its response to therapy.

  Study EGAS00001001752