Search Results - EGA European Genome-Phenome Archive

Uveal Melanoma Immunogenomics Predict Immunotherapy Resistance and Susceptibility

Immunotherapy using immune checkpoint inhibition (ICI) has shown success in treating metastatic cutaneous melanoma but has limited efficacy against metastatic uveal melanoma (UM), a rare variant arising from the immune privileged eye. To better understand this immune resistance, we performed comprehensive immunogenomic profiling of 100 human UM metastases using clinicogenomics, bulk and single cell transcriptomics, T cell receptor (TCR) repertoire analysis, and tumor infiltrating lymphocyte (TIL) potency assessment. We found that over half of these metastases harbored TIL with potent autologous tumor specificity, despite having low tumor mutational burden and resistance to prior immunotherapies, including ICI and the bispecific T cell engager tebentafusp. These T cell infiltrated metastases displayed activated antigen presenting cells, chronic interferon signaling, and diverse TCR repertoires. However, we observed strikingly low intratumoral TCR clonality and transcriptionally non-proliferative TIL within the tumor microenvironment even after ICI and tebentafusp therapy, demonstrating that these immunotherapies were insufficient to induce proliferation of the tumor reactive TIL. To harness the therapeutic potential of these quiescent TIL, we developed rapid tumor transcriptomic profiling to enable their selective in vivo identification and ex vivo liberation to counter their growth suppression. We demonstrate that adoptive transfer of these transcriptomic selected TIL can promote tumor immunity in patients with metastatic UM when other immunotherapies are incapable.Data that will be available through dbGaP includes raw bulk tumor transcriptomic sequencing data.

Study phs003330

Re-Evaluation of Systemic Early Neuromuscular Blockade

This study of the ROSE trial data explored two distinct molecular subtypes of ARDS (Acute Respiratory Distress Syndrome) to better understand the disease's complexity and potential for personalized treatment. Previous studies had identified different inflammatory profiles in ARDS patients, with this research addressing three key questions: Can these molecular subtypes be consistently identified in a more severe group of ARDS patients? Do these subtypes respond differently to neuromuscular blockade treatment? What specific biological processes differentiate these inflammatory profiles? Advanced transcriptomic and protein analyses examined blood samples from ARDS patients. Analysis of these data revealed two main molecular phenotypes: Hypoinflammatory phenotype (60.4% of patients) Hyperinflammatory phenotype (39.6% of patients) Key findings demonstrated that the hyperinflammatory subtype was associated with:Significantly higher mortality rates relative to hypoinflammatory (61.6% vs. 30.3%)Significantly higher mortality rates relative to hypoinflammatory (61.6% vs. 30.3%)Distinct gene expression patterns related to immune responseUnique changes in genes associated with tissue remodeling and cellular processes Notably, the neuromuscular blockade treatment showed no difference in effects across these subtypes. Complex relationships emerged between gene expression and protein levels, with some genes closely matching their protein counterparts and others displaying more variable connections. The study concludes that these molecular phenotypes possess distinct clinical, protein, and genetic characteristics, suggesting potential for more precise, personalized approaches to ARDS treatment in the future.

Study phs003929

Exome and RNA sequencing of relapsed TCF3-PBX1 t(1;19) acute lymphoblastic leukemia

TCF3-PBX1 (E2A-PBX1) is a recurrent gene fusion in B-cell precursor lymphoblastic leukemia (BCP-ALL), which is caused by the translocation t(1;19)(q23;p13). TCF3-PBX1 BCP-ALL patients typically benefit from chemotherapy; however, many relapse and subsequently develop resistant disease with few effective treatment options. Mechanisms driving disease progression and therapy resistance have not been studied in TCF3-PBX1 BCP-ALL. Here, we aimed to identify novel treatment options for TCF3-PBX1 BCP-ALL by profiling leukemia cells from a relapsed patient, and determine molecular mechanisms underlying disease pathogenesis and progression. By drug sensitivity testing of leukemic blasts from the index patient, control samples and TCF3-PBX1 positive and negative BCP-ALL cell lines, we identified the phosphatidylinositide 3-kinase delta (p110δ) inhibitor idelalisib as an effective treatment for TCF3-PBX1 BCP-ALL. This was further supported by evidence showing TCF3-PBX1 directly regulates expression of PIK3CD, the gene encoding p110δ. Other somatic mutations to TP53 and MTOR, as well as aberrant expression of CXCR4, may influence additional drug sensitivities specific to the index patient and accompanied progression of the disease. Our results suggest that idelalisib is a promising treatment option for patients with TCF3-PBX1 BCP-ALL while other drugs could be useful depending on the genetic context of individual patients.

Study EGAS00001001876

Centers for Common Disease Genomics (CCDG) - Whole Genome Sequencing in Type 1 Diabetes (T1DGC)

The Type 1 Diabetes Genetics Consortium (T1DGC) was established to collect resources (biological samples and data) and conduct research to better understand the genetic basis of type 1 diabetes (T1D). Collection was initiated by ascertaining affected sib-pair families (both parents, two affected siblings and, when available, an unaffected sibling), collected from five geographic regions through four recruitment networks (Asia-Pacific, Europe, North America, United Kingdom). In addition, the T1DGC collected trio families (both parents and affected child) and cases and controls from low-prevalence populations (African-American, with four grandparents self-reporting as African ancestry; Mexican-American, with four grandparents self-reporting as ancestry from Mexico). The T1DGC also served as a repository for contributed collections from other studies, all meeting the broad data-sharing policy of the T1DGC, for inclusion in the genetic studies. These collections include T1D case samples ascertained from the UK Genetic Resource Investigating Diabetes (UK GRID) cohort, SEARCH for Diabetes in Youth (SEARCH), The Genetics of Kidneys in Diabetes (GoKinD), and control samples obtained from the British 1958 Birth Cohort, the UK National Blood Services collection, CLEAR (Consortium for the Longitudinal Evaluation of African-Americans with Early Rheumatoid Arthritis), the New York Cancer Project (NYCP), and other cohorts. For the NHGRI-funded Centers for Common Disease Genomics (CCDG) project, participants with T1D and ancestry-matched controls were identified through the T1DGC, either through direct ascertainment or by contribution from other sources to the T1DGC. As the CCDG has focused initially on non-Caucasian populations for whole genome sequencing, T1DGC participants of African, Mexican and Asian ancestry (targeting ~1200 cases and ~1200 controls in each ancestral group) and a small group of participants of Northern European ancestry (~100 cases, ~100 controls) were to be contributed to the study. Whole genome sequencing of T1DGC samples would be conducted at Washington University McDonnell Genome Institute and based upon matching case-control status within an ancestry group and prioritization by the CCDG.

Study phs001222

Research of factors related to diagnosis, progression, prognosis and treatment of hepato-biliary-pancreatic malignancies

Advanced cancers with metastasis and/or recurrence are usually resistant and refractory to treatment. In our studies, whole exome sequencing analysis, comprehensive epigenetic analysis and genome-wide expression analysis were performed using cancerous and non-cancerous tissues derived from multicentric cohort study of hepatocellular carcinoma (HCC). The aim of the studies is identification of the refractoriness-related deriver genes for application to novel molecular targeted therapy and preventive medicine. The studies are intended for refractory HCC. High frequency of the tumor recurrence even after curative resection is one of the major difficulties in the treatment of HCC. According to our previous studies, not the recurrence itself, but the recurrence pattern has critical effects on prognosis of the patient with HCC. Then, we analyzed the cancerous and non-cancerous tissues of primary HCC on the point of the recurrence patterns in accordance with or without Milan criteria. The materials were obtained from thirty three patients underwent curative hepatectomy for HCC at Department of Hepato-Biliary-Pancreatic Surgery, Tokyo Medical and Dental University Hospital. Written informed consent from these patients, as well as the institutional review board approved was obtained. The determination of the refractory HCC group (16 cases) was based on the point of the recurrence patterns in accordance with Milan criteria for the recurrent tumor (solitary <5cm, or up to 3 nodules <3 cm, without major vascular invasion or distant metastasis) that has been proposed as the useful criteria of the liver transplantation for HCC. The cellular DNA was extracted from the cancerous and non-cancerous tissues of primary HCC by the phenol-chloroform method. After SNP certification using Genome-Wide Human SNP Array 6.0 (Affymetrix), whole exome sequencing was performed at the Cancer Institute of JFCR, as the support infrastructure. Exome sequencing was performed using HiSeq 2000 (Illumina), and the obtained reads were mapped to the human reference genome (hg19) using BWA software. GATK software was used for local realignment base call recalibration. Single nucleotide variants (SNVs) and indels were analyzed by MuTect and SomaticIndelDetector, as well as visual confirmation by IGV software.

Study JGAS000052

Therapeutic Resistance to PI3K-alpha Inhibitors

We have studied the tumor genomic evolution in a patient with metastatic breast cancer bearing an activating PIK3CA mutation. The patient was treated with the PI3Kα inhibitor BYL719 and achieved a lasting clinical response on BYL719, but eventually progressed to treatment and died shortly thereafter. A rapid autopsy was performed and a total of 14 metastatic lesions were collected for further analysis. In order to identify possible genetic determinants of acquired resistance to PI3Kα inhibition, we took a three-step approach. First, we examined both the primary tumor (before BYL719 treatment) and the new lung metastasis by whole genome sequencing (DNA from the spleen was used as a normal control). Then, we analyzed the primary tumor, lung metastasis, and the peri-aortic lesion that remained stable (responding) at the time of progression to BYL719 therapy by whole exome sequencing. Finally, to confirm and expand our findings, we sequenced the primary tumor and all the metastatic lesions to >500-fold coverage using a custom targeted deep-sequencing assay, MSK-IMPACT. Using this 3-step approach, we have demonstrated that patient’s lesion underwent parallel genetic evolution at multiple metastatic sites with different PTEN genomic alterations leading to a convergent PTEN- null phenotype resistant to PI3Kα inhibition. In order to expand our observations, we analyzed paired samples (pre-treatment and at progression) from six additional patients enrolled in the BYL719 trial. Acquired bi-allelic loss of PTEN was found in one additional patient treated with BYL719 whereas in two patients PIK3CA mutations present in the primary tumor were no longer detected at the time of progression. To functionally characterize our findings, inducible PTEN knockdown in sensitive cells resulted in resistance to BYL719, while simultaneous PI3K-p110β blockade reverted this resistance phenotype, both in cell lines and in PTEN-null xenografts derived from our patient. We conclude that parallel genetic evolution of separate sites with different PTEN genomic alterations leads to a convergent PTEN-null phenotype resistant to PI3Kα inhibition.

Study EGAS00001000991

APOBEC mutagenesis is a common process in normal human small intestine

The single base substitution mutational signatures SBS2 and SBS13, likely caused by APOBEC cytosine deaminases, are common in many human cancer types. However, the stimulus activating APOBEC mutagenesis is unknown and understanding of when it occurs in the progression from normal to cancer cell is limited. Here, as part of a wider survey of human tissues, we whole genome sequenced 342 microdissected normal epithelial crypts from the small intestines of 39 individuals. SBS2/13 mutations were present in 17% normal small intestine crypts and were likely due to APOBEC3A activity. Localised clusters of SBS2/13 mutations (kataegis) were also commonly found. APOBEC mutation burdens were variable between individuals and between crypts from the same individual. Crypts with SBS2/13 often had immediate crypt neighbours without SBS2/13, suggesting that the underlying cause of SBS2/13 is cell-intrinsic rather than a widely distributed microenvironmental exposure, or needs to be permitted by cell-intrinsic conditions. APOBEC mutagenesis occurred throughout the human lifespan, including in young children, and was episodic with a small number of episodes occurring during the life history of a single cell. The results indicate that APOBEC mutagenesis is more common in the small intestine epithelium than in many other cell types, and is an episodic process in vivo initiated or permitted by cell intrinsic factors.

Dataset EGAD00001008764

CAGE-seq analysis of osteoblast derived from cleidocranial dysplasia human induced pluripotent stem cells

Non-coding RNAs (ncRNAs) comprise a major portion of transcripts and serve an essential role in biological processes. Although the importance of major transcriptomes in osteogenesis has been extensively studied, the function of ncRNAs in human osteogenesis remains unclear. Previously, we developed hiPSCs from patients with cleidocranial dysplasia (CCD) caused by runt-related transcription factor 2 (RUNX2) haploinsufficiency. To gain insight into ncRNAs in osteogenesis, we surveyed differential ncRNA expression profiling and promoter differences of RUNX2 using patient-specific iPSCs and cap analysis gene expression (CAGE) technology to define the promoter landscape. Revertant iPSCs (Rev1 iPSCs) edited by CRISPR/Cas9 system to harbor mutation-corrected RUNX2 exhibited increased proximal promoter expression of RUNX2, while CCD iPSCs did not. We identified 2271 ncRNA genes with altered expression levels before and after differentiation, 31 of which showed at least 20-fold higher expression in Rev1 iPSCs. Bioinformatic analysis also categorized AC007392.3, LINC00379, RP11-122D10.1, and RP11-90J7.2 as enhancer regulatory regions, and HOXA-AS2, MIR219-2, and RP11-834C11.3 as dyadic regulatory regions of these ncRNAs. In addition, two miRNAs, termed MIR199A2 and MIR152, were found to have high enrichment of osteogenic-related terms. Upon further examination of the role of MIR152 on osteoblast differentiation, we found that MIR152 knockdown induced upregulation of ALP and COL1A1 in Saos-2 cells. Thus, ncRNAs were found to regulate the osteogenic differentiation potentials of hiPSCs that are used for bone regeneration and repair owing to their differentiation potentials. These data allow understanding ncRNA profiles of hiPSCs during osteogenesis.

Study JGAS000248

Genetic Determinants of EGFR-Driven Lung Cancer Growth and Therapeutic Response In Vivo

Oncogenic alterations in EGFR frequently co-occur with additional genetic alterations in EGFR-driven lung adenocarcinoma (LUAD), but how specific combinations of mutations affect tumor phenotypes and responses to targeted therapy is yet unknown. We leveraged a genetically engineered mouse model of EGFR mutant/Trp53-deficient LUAD to study the consequences of inactivating 10 different tumor suppressor genes on the fitness and tyorosine kinase inhibitor (TKI) sensitivity of these tumors. We found that loss of Keap1 is associated with a reduced response to therapy. In patients, we found that mutations in the KEAP1/NFE2L2/CUL3 pathway are associated with a significantly shorter time to treatment failure for EGFR TKI therapy compared to matched patients with wild-type KEAP1/NFE2L2/CUL3 tumors. We also analyzed whole exome sequencing data from tumor specimens before TKI treatment and at the time of treatment resistance for mutations in the KEAP1 pathway and these data are being submitted here.  

Study phs002334

Spatial Transcriptomics Reveals Discrete Tumor Microenvironments and Autocrine Loops Within Ovarian Cancer Subclones

Ovarian masses from patients with high grade serous ovarian carcinoma undergoing debulking surgery were subjected to spatial transcriptomics profiling using the 10x Genomics Visium (fresh frozen) platform. Copy number inference using inferCNV predicted the presence of subclones with mutually exclusive copy number alterations (CNAs) in 5 of the 8 patient samples studied. In one patient, 3 subclones were predicted. For this patient sample, a serial section of the same tumor was used to microdissect regions corresponding to each of these subclones, and a 'normal' region predicted to contain only fibroblasts and no tumor cells. These microdissected regions were processed for low pass whole genome sequencing (WGS) and CNAs recorded using ichorCNA. An oral biopsy lacking tumor cells from an unrelated donor was used as a negative control for CNA inference. The CNAs predicted by inferCNV for the three subclones were validated by the low pass WGS and no CNAs were observed in the normal region containing fibroblasts.

Study phs003561

Neoadjuvant nivolumab or nivolumab plus ipilimumab in early-stage triple negative breast cancer: phase 2 adaptive BELLINI trial. WES

The adaptive BELLINI trial explored whether short combination ICI induces immune activation (primary endpoint: two-fold increase in CD8+ T cells or IFNG), providing rationale for neoadjuvant ICI without chemotherapy. In window of opportunity cohorts A (4 weeks anti-PD1) and B (4 weeks anti-PD1 + anti-CTLA4), we observed immune activation in 53% (8/15) and 60% (9/15) of patients, respectively. High tumor-infiltrating lymphocytes (TILs) correlated with response. Based on these data, we opened cohort C for patients with high TILs (≥50%) who received 6 weeks neoadjuvant anti-PD1 + anti-CTLA4 followed by surgery (primary endpoint: pathological complete response, pCR). 53% (8/15) of patients had major pathological response (< 10% viable tumor) at resection, with 33% (5/15) having pCR. All cohorts met Simon’s two-stage threshold for expansion to stage II. In conclusion, neoadjuvant immunotherapy without chemotherapy demonstrates potential efficacy and warrants further investigation in patients with early TNBC.

Study EGAS50000000568

Oncogenic FOXL2C134W has gain-of-function chromatin remodeling activity that reprograms glucocorticoid receptor occupancy to promote ovarian granulosa cell tumor growth

Adult type ovarian granulosa cell tumors (AGCTs) are rare malignancies with near universal somatic mutation c.C402G (p.Cys134Trp) in FOXL2, a forkhead box-family transcription factor important for ovarian function. Relapsed AGCT is incurable and the mechanism of the unique FOXL2 mutation remains incompletely understood. To identify FOXL2C134W-dependent pharmacologic synergies, we created and characterized endogenous FOXL2 isogenic AGCT cells and an AGCT tumoroid biobank. A drug screen identified that glucocorticoids promote FOXL2C134W-dependent AGCT growth. Epigenetic investigation revealed that the Cys134Trp mutation exposes latent DNA sequence-specific pioneering activity in FOXL2, a unique oncogenic mechanism. FOXL2C134W pioneering activity redirects glucocorticoid receptor chromatin occupancy to drive hyaluronan synthase 2 gene expression and increase extracellular hyaluronan secretion. Treatment of AGCT models with hyaluronidase reduces viability and this effect can be rescued by dexamethasone. Thus, gain-of-function pioneering activity contributes to the oncogenic mechanism of FOXL2C134W and creates a potentially targetable synergy with glucocorticoid signaling.

Study EGAS50000000622

A Comprehensive Genetic Study of Classical Hodgkin Lymphoma Using Circulating Tumour DNA

This study on classical Hodgkin lymphoma (cHL) used advanced methods to analyse circulating tumour DNA (ctDNA) in 297 cases, offering insights into its genetic landscape and linking it to disease pathophysiology and clinical progression. Key findings include the identification of whole genome duplication as a predictor of poor chemotherapy response. Additionally, a highly recurrent somatic expression quantitative trait locus of the BCL6 gene was discovered, implicating regulatory mutations in cHL pathophysiology and highlighting BCL6 as both a vulnerability and therapeutic target. Consensus clustering identified two cHL subtypes distinguished by the underlying mechanisms of genetic instability, rather than by specific genetic mutations or EBV infection. The study also linked the number and clonality of neoantigens with tumour microenvironment and response to checkpoint blockade. Finally, our results suggested ctDNA analysis as a tool to distinguish ambiguous PET/CT-positive lesions persisting after treatment, aiming to reduce unnecessary medical interventions.

Study EGAS50000000873

Identification and targeting of extremely high-risk gamma delta T-ALL in children

Acute lymphoblastic leukemia expressing the gamma delta T cell receptor (γδ T-ALL) is an uncommon, poorly understood disease. We studied 200 pediatric γδ T-ALL enrolled on clinical trials to understand the clinical and genetic features of this disease, which showed variation in outcome according to age and genetic driver. γδ T-ALL diagnosed in children under three years of age was extremely high-risk and enriched for genetic alterations leading to both LMO2 activation and STAG2 inactivation. Using patient samples and isogenic cell lines, we show that inactivation of STAG2 profoundly perturbs chromatin organization by altering enhancer-promoter looping and results in deregulation of gene expression related to T-cell differentiation. High throughput drug screening identified a vulnerability in DNA repair pathways arising from STAG2 inactivation, which was efficaciously targeted by PARP inhibition. These data provide a diagnostic and therapeutic framework for classification and risk stratification of pediatric γδ T-ALL.

Study EGAS50000000018

Genomic determinants of response and resistance to inotuzumab in B-ALL

Inotuzumab Ozogamicin (InO) is an antibody-drug conjugate which delivers calicheamicin to CD22-expressing cells. In a retrospective cohort of InO treated B-cell acute lymphoblastic leukemia (B-ALL) patients, we sought to understand the genomic determinants of response to InO. Acquired CD22 mutations were observed in 11% (3/27) of post-InO relapsed samples. CD22 mutation types were diverse (frameshift, nonsense, missense and stoploss) and we identified multiple mechanisms of mutation induced CD22 escape, including protein truncation, protein destabilization, and epitope alteration. Accelerated acquisition of mutations by error-prone DNA damage repair could drive CD22 mutation and escape. Acquired loss-of-function mutations in TP53, ATM and CDKN2A were observed, suggesting compromise of the G1/S DNA damage checkpoint as a mechanism of evading InO-induced apoptosis. In conclusion, genetic alterations modulating CD22 expression and DNA damage response influence InO efficacy. The diverse mechanisms of CD22 escape advocates for a refined approach for monitoring CD22-targeted therapy.

Study EGAS50000000067

Pyjacker identifies enhancer hijacking events in acute myeloid leukemia including MNX1 activation via deletion 7q

Acute myeloid leukemia with complex karyotype (ckAML) is characterized by high genomic complexity, including frequent TP53 mutations and chromothripsis. We hypothesized that the numerous genomic rearrangements could reposition active enhancers near proto-oncogenes, leading to their aberrant expression. We developed pyjacker, a computational tool for the detection of enhancer hijacking events, and applied it to a cohort of 39 ckAML samples. Pyjacker identified motor neuron and pancreas homeobox 1 (MNX1), a gene aberrantly expressed in 1.4% of AML patients, often as a result of del(7)(q22q36) associated with hijacking of a CDK6 enhancer. MNX1-activated cases show significant co-occurrence with BCOR mutations and a gene signature shared with t(7;12)(q36;p13) pediatric AML. We demonstrated that MNX1 is a dependency gene, as its knockdown in a xenograft model reduces leukemia cell fitness. In conclusion, enhancer hijacking is a frequent mechanism for oncogene activation in AML.

Study EGAS50000000743

UK renal cancer samples genotyped on Illumina OmniExpress BeadChip

Renal cell carcinoma (RCC) cases comprised adult patients with histologically proven RCC were collected through two sources within the UK. First, 856 cases from SORCE, a MRC collection of surgically treated RCC cases ascertained through UK clinical oncology centres. Second, 189 RCC cases collected through the ICR and Royal Marsden NHS Hospitals Trust. Cases included 590 clear cell carcinomas (CCCs), 42 papillary carcinomas (PCs), 33 chromophobe carcinomas (CCs) and 19 mixed or other histological subtypes. DNA was extracted from EDTA-venous blood samples using the conventional methods and quantified using PicoGreen (Invitrogen). Cases were genotyped using the Human OmniExpress-12 BeadChip according to the manufacturer's recommendations (Illumina Inc, San Diego, CA, USA). After strict QC, 944 cases were retained. Data provided in plink format. Controls used were data from the Wellcome Trust Case Control Consortium 2 (WTCCC2) 1958 birth cohort and the UK Blood Service Control Group (available as EGAS00000000028).

Study EGAS00001002336

Integrated genomic analysis identifies driver genes and cisplatin-resistant progenitor phenotype in pediatric liver cancer

Pediatric liver cancers (PLCs) comprise diverse diseases affecting infants, children and adolescents. Despite overall good prognosis, PLCs display heterogeneous response to chemotherapy. Integrated genomic analysis of 126 pediatric liver tumors showed a continuum of driver mechanisms associated with patient age, including new targetable oncogenes. In 10% of hepatoblastoma patients, all before 3 years old, we identified a mosaic premalignant clonal expansion of cells altered at the 11p15.5 locus. Analysis of spatial and longitudinal heterogeneity revealed an important plasticity between ‘Hepatocytic’, ‘Liver Progenitor’ and ‘Mesenchymal’ molecular subgroups of hepatoblastoma. We showed that during chemotherapy, ‘Liver Progenitor’ cells accumulated massive loads of cisplatin-induced mutations with a specific mutational signature, leading to the development of heavily mutated relapses and metastases. Drug screening in PLC cell lines identified promising targets for cisplatin-resistant progenitor cells, validated in mouse xenograft experiments. These data provide new insights into cisplatin resistance mechanisms in PLC and suggest alternative therapies.

Study EGAS00001005108

Multimodal Genomic Features Predict Outcome of Immune Checkpoint Blockade in Non-small Cell Lung Cancer

Despite progress in immunotherapy, identifying patients that respond has remained a challenge. Through analysis of whole-exome and targeted sequence data from 5,449 tumors, we found a significant correlation between tumor mutation burden (TMB) and tumor purity, suggesting that low tumor purity tumors are likely to have inaccurate TMB estimates. We developed a new method to estimate a corrected TMB (cTMB) that was adjusted for tumor purity and more accurately predicted outcome to immune checkpoint blockade (ICB). To identify improved predictive markers together with cTMB, we performed whole-exome sequencing for 104 lung tumors treated with ICB. Through comprehensive analyses of sequence and structural alterations, we discovered a significant enrichment in activating mutations in receptor tyrosine kinase (RTK) genes in non-responding tumors in three immunotherapy-treated cohorts. An integrated multivariable model incorporating cTMB, RTK mutations, smoking-related mutational signature, and HLA status provided an improved predictor of response to immunotherapy that was independently validated.

Study EGAS00001003892

The evolution of hematopoietic cells under cancer therapy

Chemotherapies may increase mutagenesis of healthy cells and change the selective pressures in tissues thus influencing their evolution. However, their contributions to the mutation burden and clonal expansions of healthy somatic tissues are not clear. Here, exploiting the mutational footprint of some chemotherapies, we explore their influence on the evolution of hematopoietic cells. Cells of Acute Myeloid Leukemia (AML) secondary to treatment with platinum-based drugs showed the mutational footprint of these drugs, indicating that non-malignant blood cells received chemotherapy mutations. No trace of 5-fluorouracil (5FU) mutational signature was found in AML secondary to exposure to 5FU, suggesting that cells establishing the AML were quiescent during treatment. Using the platinum-based mutational signature as a barcode, we determined that secondary AMLs began their clonal expansion after the start of the cytotoxic treatment. Its absence in clonal hematopoiesis cases is consistent with a clonal expansion that predates the exposure to the cytotoxic agent.

Study EGAS00001005234

The genomic and immune landscape of long-term survivors of high-grade serous ovarian cancer

Less than half of all patients with advanced-stage high-grade serous ovarian cancers (HGSC) survive more than five years post-diagnosis but those who have an exceptionally long survival could provide insights into tumor biology and therapeutic approaches. We analyzed 60 patients with advanced-stage, HGSC who survived more than 10 years after diagnosis using whole-genome sequencing, transcriptome, and methylome profiling of their primary tumor samples, comparing this data to 66 short- or moderate-term survivors. Tumors of long-term survivors were more likely to have multiple alterations in genes associated with DNA repair, and more frequent somatic variants resulting in an increased predicted neoantigen load. Patients clustered into survival groups based on genomic and immune cell signatures, including three subsets of patients with BRCA1 alterations with distinctly different outcomes. Specific combinations of germline and somatic gene alterations, tumor cell phenotypes, and differential immune responses appear to contribute to long-term survival in HGSC.

Study EGAS00001005984

Comprehensive genomic and transcriptomic analysis of three synchronous primary tumours and a recurrence from a head and neck cancer patient

Synchronous primary malignancies occur in a small proportion of head and neck squamous cell carcinoma patients. Here, we analysed three synchronous primaries and a recurrence from one patient, by comparing the genomic and transcriptomic profiles among the tumour samples and determining the recurrence origin. We found remarkable levels of heterogeneity among the primary tumours, and through the patterns of shared mutations, we traced the origin of the recurrence. Interestingly, the patient carried germline variants which might have predisposed him to carcinogenesis, together with a history of alcohol and tobacco consumption. Mutational signature analysis confirmed the impact of alcohol exposure, with Signature 16 present in all tumour samples. Characterisation of immune cell infiltration highlighted an immunosuppressive environment in all samples, which exceeded the potential activity of T cells. Studies such as the one described here have important clinical value and contribute to personalised treatment decisions for patients with synchronous primaries and matched recurrences.

Study EGAS00001004857

Phase 1 CX-5461 Trial (Canadian Cancer Trials Group Trial IND.231)

CX-5461 is a G-quadruplex stabilizer that exhibits synthetic lethality in homologous recombination (HR) deficient models. In this multicentre Phase Ib trial in patients with solid tumors, 40 patients were treated across 10 dose levels (50 - 650 mg/m2) to determine the recommended phase II dose (RP2D), and evaluate safety, tolerability, pharmacokinetics. Defective HR was explored as a predictive biomarker. CX-5461 was generally well tolerated, with a RP2D of 475 mg/m2 d1, 8 and 15 every 4 weeks, and dose limiting toxicities of phototoxicity. Responses were observed in 10% of patients, primarily in patients with defective HR (ORR 14%). Reversion mutations in PALB2 and BRCA2 were detected on progression following initial response in germline carriers, confirming the underlying synthetic lethal mechanism. In vitro characterization of UV sensitization showed this toxicity is related to the CX-5461 chemotype, independent of G4 synthetic lethality. These results establish clinical proof-of-concept for this first-in class G4 stabilizer.

Study EGAS00001006173

ANGIOPREDICT - an FP7-funded project enabling personalised medicine for patients with metastatic colorectal cancer.

Exome (*_{N,T}{1,2}) RNAseq (polyA - *_PolyA, and RiboZero - *_RibZ) Methylation (SeqCapEpi - MAPD*).

Dataset EGAD00001008463

pancreatic ductal adenocarcinoma exomes in study: Pro-immunogenic Impact of MEK inhibition combined with an anti-CD40 immunostimulatory antibody

This dataset contains 3 pairs of exomes, germline (from whole blood) and patient-derived xenograft (PDX), from human pancreatic durctal adenocarcinoma patients. The data is referred to in the publication: "Pro-immunogenic impact of MEK inhibition synergizes with agonist anti-CD40 immunostimulatory antibodies in tumor therapy" (Nature Communications, 2020) Abstract: Cancer types with lower mutational load and a non-permissive tumor microenvironment are intrinsically resistant to immune checkpoint blockade. While the combination of cytostatic drugs and immunostimulatory antibodies constitutes an attractive concept for overcoming this refractoriness, suppression of immune cell function by cytostatic drugs may limit therapeutic efficacy. Here we show that targeted inhibition of mitogen-activated protein kinase (MAPK) kinase (MEK) does not impair dendritic cell-mediated T-cell priming and activation. Accordingly, combining MEK inhibitors (MEKi) with agonist antibodies (Abs) targeting the immunostimulatory CD40 receptor resulted in potent synergistic anti-tumor efficacy. Detailed analysis of the mechanism of action of MEKi GDC-0623 by means of flow cytometric analysis of the tumor immune infiltrate and whole tumor transcriptomics showed that, in addition to its cytostatic impact on tumor cells, this drug exerts multiple pro-immunogenic effects, including the suppression of M2-type macrophages, myeloid derived suppressor cells and CD4+ T-regulatory cells. In addition, MEKi was found to induce tumor-cell intrinsic interferon signaling, which contributed to antigen presentation by tumor cells. Finally, the tumoridical impact of MEKi involves the activation of multiple pro-inflammatory pathways involved in immune cell effector function in the tumor microenvironment. Our data therefore indicate that the combination of MEK inhibition with agonist anti-CD40 Ab is a promising therapeutic concept, especially for the treatment of mutant Kras-driven tumors such as pancreatic ductal adenocarcinoma.

Dataset EGAD00001005938

11988 results for "cancer rna-seq"

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