12377 results for ""statistically+reactive"+taxa+in+microbial+community"

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• PAX5 biallelic genomic alterations define a novel subgroup of B cell precursor acute lymphoblastic leukemia

  Chromosomal rearrangements and specific aneuploidy patterns are initiating events and define subgroups in B cell precursor acute lymphoblastic leukemia (BCP-ALL). Here we analyzed 250 BCP-ALL cases and identified a novel subgroup (‘PAX5-plus’, n=19) by distinct DNA methylation and gene expression profiles. All patients in this subgroup harbored mutations in the B-lineage transcription factor PAX5, with p.P80R as hotspot. Mutations either affected two independent codons, consistent with compound heterozygosity, or suffered LOH predominantly through chromosome 9p aberrations. These biallelic events resulted in disruption of PAX5 transcriptional programs regulating B cell differentiation and tumor suppressor functions. Homozygous CDKN2A/B deletions and RAS activating hotspot mutations were highly enriched as cooperating events in the genomic profile of PAX5-plus ALL. Together this defined a specific pattern of triple alterations, exclusive to the novel subgroup. PAX5-plus ALL was observed in pediatric and adult patients. Although restricted by the limited sample size, a tendency for more favorable clinical outcome was observed with 10 of 12 adult PAX5-plus patients achieving long-term survival. PAX5-plus represents the first BCP-ALL subgroup defined by sequence alterations in contrast to gross chromosomal events and exemplifies how deregulated differentiation (PAX5), impaired cell cycle control (CDKN2A/B) together with sustained proliferative signaling (RAS) cooperatively drives leukemogenesis.

  Study EGAS00001003209

• Molecular analysis of post-colonoscopy CRC (PCCRC)

  Background: Post-colonoscopy colorectal cancers (PCCRCs, i.e. CRC diagnosed after a colonoscopy that excluded cancer) pose a challenge in clinical practice. In a retrospective cohort study, we compared clinical and molecular features of PCCRCs and prevalent CRCs. Methods: PCCRCs were defined according to the WEO classification, as cancers occurring within 10 years after a complete index colonoscopy, which excluded CRC. Whole genome chromosomal copy number changes and mutation status of genes commonly affected in CRC (APC, KRAS, BRAF, FBXW7, PIK3CA, NRAS, SMAD4 and TP53) were examined by low-coverage WGS and targeted sequencing, respectively. MSI and CIMP status were also determined. Results: In total, 122 PCCRCs and 98 prevalent CRCs were examined. PCCRCs are more often located proximally in the colon (p<0.001), non-polypoid appearing (p=0.004), early stage (p=0.009), and poorly differentiated (p=0.006) compared to prevalent CRCs. PCCRCs contain less frequently 18q deletions (p<0.001) than prevalent CRCs. MSI (p=0.029) and CIMP (p=0.014) are more frequently observed in PCCRCs. Conclusion: Although no PCCRC specific pathway could be defined, PCCRCs’ molecular features are more associated with MSI and hypermethylation pathways than canonical CIN pathway. The clinical and molecular features observed in PCCRCs support the hypothesis that sessile serrated lesions and non-polypoid CRNs are contributors to the development of these cancers."

  Study EGAS00001004686

• Unraveling the transcriptomic profile of utero-tubal lavage fluid of ovarian cancer patients

  The majority of ovarian cancers are diagnosed at an advanced stage and have a high mortality rate. Current screening strategies fail to improve prognosis because markers of early stage disease are lacking. This medical need justifies the search for biomarkers enabling early detection of ovarian cancer. In this study, we explore the extracellular transcriptome of utero-tubal lavage fluid obtained from 26 ovarian cancer patients and 48 controls using messenger RNA (mRNA) capture and small RNA sequencing. Because of its contact with the fallopian tube and the ovaries, collection of utero-tubal lavage might be the preferred non-invasive method to identify localized lesions compared with analyses based on peripheral blood samples. We observed an enrichment of ovarian and fallopian tube specific messenger RNAs in utero-tubal lavage fluid compared to other human biofluids. Over 300 mRNAs and 41 miRNAs were upregulated in ovarian cancer samples compared with controls. Upregulated genes were enriched for genes involved in cell cycle activation and proliferation, hinting at a tumor derived signal. In conclusion, we provide proof-of-principle that mRNA capture sequencing of utero-tubal lavage fluid is technically feasible, and that the extracellular transcriptome of utero-tubal lavage should be further explored in larger cohorts to assess the diagnostic value of the biomarkers identified in this study.

  Study EGAS00001005498

• SG Peranakan Project: Genetic admixture in the culturally unique Peranakan Chinese population in Southeast Asia

  The Peranakan Chinese are culturally unique descendants of immigrants from China who settled in the Malay Archipelago ~300-500 years ago. Today, among large communities in Southeast Asia, the Peranakans have preserved Chinese traditions with strong influence from the local indigenous Malays. Yet, whether or to what extent genetic admixture co-occurred with the cultural mixture has been a topic of ongoing debate. We performed whole-genome sequencing (WGS) on 177 Singapore (SG) Peranakans and analyzed the data jointly with WGS data of Asian and European populations. We estimated that Peranakan Chinese inherited ~5.62% (95% confidence interval [CI]: 4.75-6.46%) Malay ancestry, much higher than that in SG Chinese (1.08%, 0.69-1.53%), southern Chinese (0.86%, 0.57-1.31%), and northern Chinese (0.25%, 0.18-0.33%). A sex-biased admixture history, in which the Malay ancestry was contributed primarily by females, was supported by X chromosomal variants, and mitochondrial (MT) and Y haplogroups. Finally, we identified an ancient admixture event shared by Peranakan Chinese and SG Chinese ~1,612 (95% CI: 1,345-1,923) years ago, coinciding with the settlement history of Han Chinese in southern China, apart from the recent admixture event with Malays unique to Peranakan Chinese ~190 (159-213) years ago. These findings greatly advance our understanding of the dispersal history of Chinese and their interaction with indigenous populations in Southeast Asia.

  Study EGAS00001005379

• Comprehensive Genomic Characterization of Gene Therapy-Induced T-cell Acute Lymphoblastic Leukemia (H007)

  Six out of ten patients in a hematopoietic stem cell gene therapy (GT) trial for Wiskott-Aldrich syndrome (WAS) developed T-cell acute lymphoblastic leukemia (T-ALL) associated with gamma-retroviral vector integration at the LMO2 locus. We hypothesized that detailed molecular analysis of T-ALL driven by temporally defined first deregulation of LMO2 might offer valuable insights into the pathogenesis of GT-associated and sporadic T-ALL (HIPO project 007). In all six patients whole-genome and transcriptome sequencing demonstrated that in addition to oncogenic chromosomal translocations involving the T-cell receptor loci, retrovirally induced leukemias faithfully recapitulated secondary genomic events observed in sporadic T-ALL. Multiple genetic events culminated in the development of a rapidly proliferating leukemic clone and onset of clinical manifestation at 1.3 to 5 years after infusion of the gene corrected transplant. These genetic alterations affected NOTCH1 and PI3K signaling, cell cycle regulation as wells as T-cell transcription factors LEF1 and TCF1. Two of the six cases displayed a phenotype reminiscent of early immature T-ALLs, and lacked additional T-ALL typical alterations. Our analysis shows that insertional mutagenesis involving the LMO2 locus triggers T-ALL development due to diverse genetic alterations in large parts, but not exclusively, in known T-ALL driver genes, demonstrating the molecular diversity of GT-associated T-ALL.

  Study EGAS00001003870

• Genomics to select patients with metastatic breast cancer for targeted therapy (microarray_cytoscan)

  Cancer progression is driven in part by genomic alterations located in oncogenes or tumor suppressor genes. The genomic characterization of cancers has shown a large interpatient heterogeneity regarding the driver alterations, leading to the concept that generating a genomic profiling by multigene sequencing in patients with cancer could allow selecting effective targeted therapies. While this concept has been broadly implemented in daily practice, there is no evidence that such approach improves patient outcome, and how to optimally select the therapy to administer. A genomic profiling using next generation sequencing and copy number analyses was performed 1462 patients with Her2-non overexpressing metastatic breast cancer included in SAFIR02 Breast trial. 238 of these patients were randomized in two trials between a targeted therapy matched to genomic alteration and a maintenance chemotherapy. The trial shows that targeted therapies matched to genomics improves progression free survival (PFS) when genomic alterations are classified level I/II according to ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) (adjusted HR: 0.41, 90% CI: 0.27-0.61, p<0.001), but not when alterations are classified beyond level II (unadjusted HR: 1.15, 95% CI: 0.76-1.75). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with mBC.

  Study EGAS00001005584

• Genomics to select patients with metastatic breast cancer for targeted therapy (microarray_oncoscan)

  Cancer progression is driven in part by genomic alterations located in oncogenes or tumor suppressor genes. The genomic characterization of cancers has shown a large interpatient heterogeneity regarding the driver alterations, leading to the concept that generating a genomic profiling by multigene sequencing in patients with cancer could allow selecting effective targeted therapies. While this concept has been broadly implemented in daily practice, there is no evidence that such approach improves patient outcome, and how to optimally select the therapy to administer. A genomic profiling using next generation sequencing and copy number analyses was performed 1462 patients with Her2-non overexpressing metastatic breast cancer included in SAFIR02 Breast trial. 238 of these patients were randomized in two trials between a targeted therapy matched to genomic alteration and a maintenance chemotherapy. The trial shows that targeted therapies matched to genomics improves progression free survival (PFS) when genomic alterations are classified level I/II according to ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) (adjusted HR: 0.41, 90% CI: 0.27-0.61, p<0.001), but not when alterations are classified beyond level II (unadjusted HR: 1.15, 95% CI: 0.76-1.75). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with mBC.

  Study EGAS00001005586

• Genomics to select patients with metastatic breast cancer for targeted therapy (microarray_agilent)

  Cancer progression is driven in part by genomic alterations located in oncogenes or tumor suppressor genes. The genomic characterization of cancers has shown a large interpatient heterogeneity regarding the driver alterations, leading to the concept that generating a genomic profiling by multigene sequencing in patients with cancer could allow selecting effective targeted therapies. While this concept has been broadly implemented in daily practice, there is no evidence that such approach improves patient outcome, and how to optimally select the therapy to administer. A genomic profiling using next generation sequencing and copy number analyses was performed 1462 patients with Her2-non overexpressing metastatic breast cancer included in SAFIR02 Breast trial. 238 of these patients were randomized in two trials between a targeted therapy matched to genomic alteration and a maintenance chemotherapy. The trial shows that targeted therapies matched to genomics improves progression free survival (PFS) when genomic alterations are classified level I/II according to ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) (adjusted HR: 0.41, 90% CI: 0.27-0.61, p<0.001), but not when alterations are classified beyond level II (unadjusted HR: 1.15, 95% CI: 0.76-1.75). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with mBC.

  Study EGAS00001005587

• Targeted de-methylation of the FOXP3-TSDR

  CD4+ regulatory T cells (Tregs) are key mediators of immunological tolerance and promising effector cells for immuno-suppressive adoptive cellular therapy to fight autoimmunity and chronic inflammation. Their functional stability is critical for their clinical utility and has been correlated to the demethylated state of the TSDR/CNS2 enhancer element in the Treg lineage transcription factor FOXP3. However, proof for a causal contribution of the TSDR de-methylation to FOXP3 stability and Treg induction is so far lacking. We here established a powerful transient-transfection CRISPR-Cas9-based epigenetic-editing method for the selective de-methylation of the TSDR within the endogenous chromatin environment of a living cell. The induced de-methylated state was stable over weeks in clonal T cell proliferation cultures even after expression of the editing complex had ceased. Epigenetic editing of the TSDR resulted in FOXP3 expression, even in its physiological isoform distribution, proving a causal role for the de-methylated TSDR in FOXP3 regulation. However, successful FOXP3 induction was not associated with a switch towards a functional Treg phenotype, in contrast to what has been reported from FOXP3 overexpression approaches. Thus, TSDR de-methylation is required, but not sufficient for a stable Treg phenotype induction. Therefore, targeted demethylation of the TSDR may be a critical addition to published in vitro Treg induction protocols which so far lack FOXP3 stability.

  Study EGAS00001004867

• Genomic insights into the pathogenesis of Epstein-Barr virus-associated diffuse large B-cell lymphoma by whole-genome and targeted amplicon-based sequencing

  Epstein–Barr virus (EBV)-associated diffuse large B-cell lymphoma not otherwise specified (DLBCL NOS) constitutes a distinct clinicopathological entity in the current World Health Organization (WHO) classification, yet its genomic features remain sparsely characterized. Combining whole-genome sequencing (WGS), targeted amplicon sequencing (tNGS) and fluorescence in-situ hybridization (FISH) of tumours from 47 cases of EBV+ DLBCL we delineate the genomic landscape of this rare disease. Interrogating WGS data by sequential gene-set enrichment and network-diffusion we describe an accumulation of mutations affecting the nuclear factor κB (NFκB) pathway (CSNK2A2, CARD10), IL-6/JAK/STAT (SOCS1/3, STAT3) and WNT signalling (FRAT1, SFRP5) alongside aberrations in immunological processes like interferon-response. Further, WGS uncovered structural aberrations including 6q deletions (5/8 patients), which were subsequently validated by FISH (14/32 cases). Integrated WGS and tNGS analysis emphasized a profile distinct from EBV-negative DLBCL enriched for mutations in ARID1A (45%), KMT2A/D (32/30%), ANKRD11 (32%), NOTCH2 (32%). Expanding on previous reports, we identified recurrent alterations in CCR6 (15%), DAPK1 (15%), TNFRSF21 (13%), CCR7 (11%) and YY1 (6%). Our comprehensive description of the mutational landscape in EBV+ DLBCL substantiates the evidence of its pathobiological independence. Further, these observations aid in the refinement of the molecular taxonomy for aggressive lymphomas and guides future therapeutic strategies.

  Study EGAS00001004941