11932 results for "cancer rna-seq"

in 18.01 milliseconds.

• 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

• Genomic landscape of oral cancers (Illumina RNA-Seq)

  Human papillomavirus (HPV) is a necessary but insufficient cause of a subset of oral squamous cell carcinomas (OSCC) that is increasing markedly in frequency. To identify contributory, secondary genetic alterations in these cancers, we used comprehensive genomics methods to compare 149 HPV-positive and 335 HPV-negative OSCC tumor/normal pairs. Different behavioral risk factors underlying the two OSCC types were reflected in distinctive genomic mutational signatures. In HPV-positive OSCC, the signatures of APOBEC cytosine deaminase editing, associated with anti-viral immunity, were strongly linked to overall mutational burden. By contrast, in HPV-negative OSCC, T>C substitutions in the sequence context 5’-ATN-3’ correlated with tobacco exposure. Universal expression of HPV E6*1 and E7 oncogenes was a sine qua non of HPV-positive OSCC. Significant enrichment of somatic mutations was confirmed or newly identified in PIK3CA, KMT2D, FGFR3, FBXW7, DDX3X, PTEN, TRAF3, RB1, CYLD, RIPK4, ZNF750, EP300, CASZ1, TAF5, RBL1, IFNGR1 and NFKBIA. Of these, many affect host pathways already targeted by HPV oncoproteins, including the p53 and pRB pathways, or disrupt host defenses against viral infections, including interferon and nuclear factor-B signaling. Frequent copy number changes were associated with concordant changes in gene expression. Chr. 11q (including CCND1) and 14q (including DICER1 and AKT1) were recurrently lost in HPV-positive OSCC, in contrast to their gains in HPV-negative OSCC. High-ranking variant allele fractions implicated ZNF750, PIK3CA and EP300 mutations as candidate driver events in HPV-positive cancers. We conclude that virus-host interactions cooperatively shape the unique genetic features of these cancers, distinguishing them from their HPV-negative counterparts.

  Study EGAS00001003237

• 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

• Netherlands Cancer Institute (NKI-AVL) general DAC

  Data is available under reasonable request. All data requests will be reviewed by the NKI IRB and must be supported by the Principal Investigator of the study. The researcher will need to sign a data access agreement with the NKI after approval. Go to https://ega.nki.nl to fill out the form to request access.

  Dac EGAC50000000055

• DELFI low-coverage WGS of plasma cfDNA

  The dataset "DELFI low-coverage WGS of plasma cfDNA" includes paired FASTQ files produced by WGS of 689 plasma cfDNA samples from 153 patients with colorectal cancer. WGS (100bp PE) was performed on a NovaSeq 6000 with a target depth of coverage of 8x.

  Dataset EGAD50000000630

• BELLINI clinical trial bulk WES data: cohorts A & B

  WES data of 30 breast cancer primary tumors obtained from 30 unique patients from BELLINI clinical trial (cohorts A & B) and 30 matched blood samples. The data includes pretreatment samples. The included raw WES sequencing data in fastq format was generated using Illumina NovaSeq 6000.

  Dataset EGAD50000000809

• eSENSES control samples

  This dataset comprises BAM files from 18 control samples analyzed with the eSENSES targeted NGS panel. Spanning approximately 2 Mb, the panel features around 15,000 evenly distributed genome-wide SNPs, over 500 focal SNPs targeting key breast cancer driver regions, and more than 2,000 exons from 81 commonly altered genes.

  Dataset EGAD50000001167