Search Results - EGA European Genome-Phenome Archive

Bulk RNAseq fastq files

RNAseq FASTq files from 15 samples from patients with ovarian cancer, 5 samples for each of the 3 tumor immune phenotypes (Infiltrated, Excluded and Desert).

Dataset EGAD00001006975

Mutational dynamics of triple negative breast cancer over neoadjuvant chemotherapy treatment reveal frequent whole genome duplication events

Background Triple-negative breast cancer (TNBC) is associated with poor survival rate and high genomic instability, generating complex tumour genomes. However, the processes generating this complexity are poorly studied over time. Here, we study the temporal dynamics of TNBC somatic mutations, revealing major transitions in tumour genome evolution, from diagnostic biopsies, through treatment, to cancer remission or recurrence. Methods Deep whole exome sequencing and CUTseq, a reduced representation whole genome sequencing approach, were performed in parallel, to comprehensively identify short nucleotide variants (SNVs), copy number alterations (CNAs) and aneuploidies genome-wide. We profiled (N=74) tumour samples from 22 patients across the course of disease, including spatially diverse samples from many tumours, allowing us to observe the gain and loss of candidate driver variants over time. Results As expected, tumour infiltrating lymphocyte (TIL) levels and residual cancer burden (RCB) score were negatively correlated, with good responses to neoadjuvant chemotherapy (NACT) seen in pre-treatment samples with high infiltration. In general, SNV mutational burden remained stable across disease progression and RCB classes. Recurrent SNVs across the cohort implicated several known TNBC driver genes in disease progression and response to treatment, with TP53, MICA, CYP2D6, BRCA1 and BRCA2 frequently altered. However, the presence of candidate driver SNVs in these genes often varied throughout a patient’s treatment, including the loss of those seen in a given driver gene in pre-treatment samples, but gain of novel variants in the same gene at later time points. Dramatic structural dynamics were seen in all tumours, including abundant CNA including chromosome arm aneuploidies seen in pre-treatment samples, followed by frequent loss of these alterations post-treatment, and their re-emergence at recurrence. Whole genome duplication (WGD) events appear to drive these dynamics, with a higher frequency of pre-treatment WGD seen in patients with the best response to NACT. Conclusions Comprehensive longitudinal profiling demonstrates the complex interplay of SNVs and copy number alterations during TNBC progression, leading to diverse evolutionary trajectories and patient outcomes. Complex mutational patterns emerge as important features during progression, with WGD events emerging as potential candidate biomarkers of response at both tumour establishment and recurrence.

Study EGAS00001008261

Follow-up of Ovarian Cancer Genetic Association and Interaction Studies (FOCI)

(Excerpted/paraphrased from original grant application): FOCI seeks to expand our understanding of epithelial ovarian cancer through a coordinated and comprehensive approach. Project 1 will focus on discovery, expansion, and replication. By pooling GWAS, we expect to identify new associations and achieve independent replication, explore whether there are risk variants specific for histologic subtypes, and evaluate structural polymorphisms - copy number variants - as risk factors. Finally, Project 1 will leverage the GWAS data to correlate DNA variants with a new endpoint - survival. Project 2 will focus on biological studies designed to help inform interpretation of findings from Project 1. This will include efforts to identify the functional consequences of variants and improve understanding of biological mechanisms. Project 3 will include epidemiologic studies of gene by gene interaction, gene by environment interaction, and development of risk prediction models. The collective effort builds upon the strengths and history of collaboration inherent in the Ovarian Cancer Association Consortium (OCAC), a multidisciplinary group comprised of epidemiologists, genetic epidemiologists, statistical geneticists, molecular and cell biologists and clinicians that was formed in 2005. The FOCI Cohort is utilized in the following dbGaP sub-studies. To view genotypes, other molecular data, and derived variables collected in these sub-studies, please click on the following sub-studies below or in the "Sub-studies" box located on the right hand side of this top-level study page phs001133 FOCI Cohort. phs001131 Affymetrix Exome Chip phs001132 GWAS Meta Analysis phs001142 Mayo Omni Express phs001150 Mayo 2 5M

Study phs001133

Circulating tumor DNA dynamics reveal KRAS G12C mutation heterogeneity and response to treatment with the KRAS G12C inhibitor divarasib in solid tumors

Purpose: To inform prognosis, treatment response, disease biology, and KRAS G12C mutation heterogeneity, we conducted exploratory circulating tumor DNA (ctDNA) profiling on 134 patients with solid tumors harboring a KRAS G12C mutation treated with single-agent divarasib (GDC-6036) in a phase 1 study. Experimental design: Plasma samples were collected for serial ctDNA profiling at baseline (Cycle 1 Day 1 prior to treatment) and multiple on-treatment time points (Cycle 1 Day 15 and Cycle 3 Day 1). Results: KRAS G12C ctDNA was detectable from plasma samples in 72.9% (43/59) and 92.6% (50/54) of patients with non-small cell lung cancer and colorectal cancer, respectively, the majority of whom were eligible for study participation based on a local test detecting the KRAS G12C mutation in tumor tissue. Baseline ctDNA tumor fraction was associated with tumor type, disease burden, and metastatic sites. A decline in ctDNA level was observed as early as Cycle 1 Day 15. Serial assessment showed a decline in ctDNA tumor fraction associated with response and progression-free survival. Except for a few cases of KRAS G12C sub-clonality, on-treatment changes in KRAS G12C variant allele frequency mirrored changes in the overall ctDNA tumor fraction. Conclusion: Across tumor types, the KRAS G12C mutation likely represents a truncal mutation in the majority of patients. Rapid and deep decline in ctDNA tumor fraction was observed in patients responding to divarasib treatment. Early on-treatment dynamics of ctDNA were associated with patient outcomes and tumor response to divarasib treatment.

Study EGAS50000000315

Detection of ctDNA in Plasma of Patients with Clinically Localised Prostate Cancer is Associated with Rapid Disease Progression

Purpose: DNA originating from degenerate tumour cells can be detected in the circulation in many tumour types, where it can be used as a marker of disease burden as well as to monitor treatment response. Although circulating tumour DNA (ctDNA) measurement has prognostic/predictive value in metastatic prostate cancer, its utility in localised disease is unknown. Patients and Methods: We performed whole genome sequencing of tumour-normal pairs in eight patients with clinically localised disease undergoing prostatectomy, identifying high confidence genomic aberrations. A bespoke DNA capture and amplification panel against the highest prevalence, highest confidence aberrations for each individual was designed and used to interrogate ctDNA isolated from plasma prospectively obtained pre- and post- (24 hours and 6 weeks) surgery. In a separate cohort (n=189) we identified the presence of ctDNA TP53 mutations in pre-operative plasma in a retrospective cohort, and determined its association with biochemical- and metastasis-free survival. Results: Tumour variants in ctDNA were positively identified pre-treatment in two of eight patients, which in both cases remained detectable postoperatively. Patients with tumour variants in ctDNA had extremely rapid disease recurrence and progression compared to those where variants could not be detected. In terms of aberrations targeted, single nucleotide and structural variants outperformed indels and copy number aberrations. Detection of ctDNA TP53 mutations was associated with a significantly shorter metastasis-free survival (6.2 vs. 9.5 years (HR 2.4; 95% CIs 1.2-4.8, p = 0.014)). Conclusions: CtDNA is uncommonly detected in localised prostate cancer but its presence portends more rapidly progressive disease.

Study EGAS00001004636

Clonal fitness inferred from timeseries modeling of single cell cancer genomes

Progress in defining genomic fitness landscapes in cancer by copy number alterations (CNA) has been impeded by lack of single cell and timeseries sampling. We generated 42,000 single cell whole genomes (scWGS) from breast epithelium and primary triple negative breast cancer (TNBC) patient-derived xenografts (PDX) collected during multi-year time series. Using a Wright-Fisher population genetics model, we inferred reproducible CNA-defined clonal fitness dynamics induced by TP53 mutation and cisplatin chemotherapy, with accurate forecasting of experimentally enforced clonal competition dynamics. Drug treatment in three long-term serially passaged TNBC PDX resulted in cisplatin resistant clones that had shown low fitness in the untreated setting. By contrast high fitness clones from treatment naive controls were eradicated reflecting an inversion of the fitness landscape. Upon drug release selective pressure dynamics were reversed indicating a fitness cost of treatment resistance. Taken together, our findings reveal clonal fitness dynamics linked to CNA and therapeutic resistance in polyclonal tumours.

Study EGAS00001004448

A higher ctDNA fraction decreases survival in regorafenib-treated metastatic colorectal cancer patients

The predictive effect of circulating tumor DNA (ctDNA) in colorectal cancer (CRC) treatment is still highly discussed. The primary objective of this study was to investigate a possible prognostic/predictive value of ctDNA under regorafenib treatment. This prospective multicenter translational biomarker phase II pilot study enrolled 30 metastatic CRC patients (67% men, 33% women) treated with regorafenib. ctDNA was assessed in plasma before treatment start and at defined time points during administration. Measurement of tumor fraction as well as mutation and copy number analysis of CRC driver genes were performed by next generation sequencing approaches. Multivariate analyses for survival and treatment efficacy were adjusted to age, gender and ECOG. Disease control rate was 30%. Median tumor fraction at baseline was 18.5% (0-49.9). Mutations in CRC driver genes or genes involved in angiogenesis were identified in 25 patients (83.3%). KRAS mutations were detected in 13 out of 14 KRAS positive tumors, in three patients without KRAS mutation in the respective tumor acquired mutations as a consequence of prior anti-EGFR treatment were detected. In a subset of patients, novel occurring mutations or focal amplifications were detected. A tumor fraction of 5% and higher at baseline was significantly associated with a decreased OS (p=0.022; HHR 3.110 (95%CI: 1.2-8.2). ctDNA is detectable in a high proportion of mCRC patients. Higher ctDNA levels are associated with survival among regorafenib treatment. Moreover, our data highlight the benefit of a combined evaluation of mutations and somatic copy number alterations (SCNA) in advanced cancer patients.

Study EGAS00001004491

Colorectal cancer study

Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and non-matrix proteins. Although most MMPs are secreted as inactive proenzymes and they are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11’s protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.

Study EGAS00001006489

PD-L1 blockade in combination with carboplatin as immune induction in metastatic lobular breast cancer: the GELATO-trial

Invasive lobular breast cancer (ILC) is the second most common histological breast cancer subtype but published data on trials specific for ILC are so far lacking. Translational research revealed that a subset of ILCs may be immune-related and more sensitive to DNA-damaging agents such as platinum. In murine ILC models, synergy between immune checkpoint blockade and platinum has been observed. Here, we tested this concept in the phase II, GELATO-trial (NCT03147040), in which patients with metastatic ILC were treated with weekly carboplatin (AUC 1.5) as immune induction treatment for 12 weeks and atezolizumab (PD-L1 blockade; every three weeks) from the third week onwards until disease progression. Four out of 23 evaluable patients had a partial response (17%, 95%CI 5-39%) and two patients had stable disease for at least 24 weeks, resulting in a clinical benefit rate of 26% (95%CI 10-48%). Out of these six patients, four patients had triple-negative ILC (TN-ILC). In serial biopsies of metastatic lesions, we observed higher CD8 T-cell infiltration, expression of immune checkpoints, and exhausted T cells upon carboplatin/PD-L1 blockade. This is the first report of a clinical trial specifically for ILC and we demonstrate promising anti-tumor activity of atezolizumab with carboplatin as immune induction, in particular for TN-ILC. While activity of carboplatin/PD-L1 blockade in classical ER+ ILC was limited, our translational data yield important insights for the design of highly needed clinical trials in ILC.

Study EGAS00001006902

The Two Sister Study: A Family-Based Study of Genes and Environment in Young-Onset Breast Cancer

To study environmental and genetic causes of young onset breast cancer, we recruited women who had been young when recently diagnosed (under age 50 and within 4 years of enrollment), and had been identified as potentially eligible by a sister who was already participating in the ongoing Sister Study. The unaffected sister had already provided consent, questionnaire-based information and DNA (blood-based) when she enrolled in the Sister Study. Her case sister then provided comparable questionnaire-based information and DNA via a mail-back saliva collection kit. To enable family-based analyses, parents were also asked to (only) provide consent and a saliva sample. Because the cases were young-onset, most parents were alive, but unavailability of the parents was not a basis for exclusion. The study was funded in part by Susan G. Komen for the Cure.

Study phs000678

11765 results for "cancer rna-seq"

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