11973 results for "cancer rna-seq"

in 16.41 milliseconds.

• Timing and trajectory of BCR-ABL1 driven chronic myeloid leukaemia

  Mutation of some genes provide fitness advantages that drive uncontrolled cell proliferation, leading to clinical manifestations of cancer. The discovery of the Philadelphia chromosome in chronic myeloid leukaemia (CML) provided the very first such genetic link to cancer and the hypothesis that this lesion provided an abnormal growth advantage to cells. However, little is known about the trajectory to CML, the rate of BCR::ABL1 driven clonal expansion, and how this impacts on disease presentation. Here, using whole-genome sequencing of 1013 single-cell-derived colonies from patients with CML, we reconstruct phylogenetic trees of haematopoiesis in 9 patients aged 22 to 81 years at diagnosis. The expected intronic breaks in BCR and ABL1 were not always observed, and out-of-frame exonic breakpoints in BCR, requiring exon skipping to derive BCR::ABL1 fusion transcripts, were noted in several patients. Apart from ASXL1 and RUNX1 mutations, additional somatic mutations in myeloid genes were generally present only in wild-type cells and did not contribute to the CML clone. Using phylogenetic analysis, we infer sustained explosive growth attributed to BCR::ABL1 fusion, with clonal expansions beginning 3-14 years (Cl 2-16 years) before diagnosis and annual growth rates exceeding 70,000% per year in some young patients with the most recent and rapid clonal expansions. Mutation rate was higher in BCR::ABL1-positive cells than in wild-type counterparts, together with markedly shorter telomere lengths, reflecting their excessive cell division history. Clonal expansion rates inferred from phylogenetic trees were in line with mutational signature patterns and telomere attrition, and inversely correlated with the time to diagnosis. Whole genome sequencing of advanced phase CML was characterised by genomic evolution within BCR::ABL1-positive cells. Our findings highlight the oncogenic potency of a single BCR::ABL1 fusion and its capacity to drive fast clonal outgrowth to cancer. These data contrast with the early-in-life, slow, and sequential clonal trajectories typical of most cancers, such as Philadelphia-negative myeloproliferative neoplasms, solid organ malignancies, and patterns of clonal expansion in healthy tissue ageing.

  Dataset EGAD00001015473

• Shifted assembly and function of mSWI/SNF family subcomplexes underlie targetable dependencies in endometriod carcinomas

  The mammalian SWI/SNF (mSWI/SNF) family of chromatin remodelers govern cell type-specific chromatin accessibility and gene expression and assemble as three distinct complexes: canonical BAF (cBAF), Polybromo-associated BAF (PBAF), and non-canonical BAF (ncBAF). ARID1A and ARID1B are paralog subunits that specifically nucleate the assembly of cBAF complexes and are frequently dual deleted in highly aggressive differentiated endometrial carcinomas (DECs). Here, in cellular models and primary human tumors, we find that ARID1A/B-mediated cBAF loss results in increased ncBAF and PBAF biochemical abundance and function genome-wide to maintain the DEC oncogenic signature. Further, treatment of ARID1A/1B-mutant cell lines and PDX models in vivo with a clinical-grade SMARCA4/2 ATPase inhibitor, FHD-286, markedly attenuates cell proliferation and tumor growth, and synergizes with carboplatin-based chemotherapy. Taken together, these findings reveal the oncogenic contributions of shifted of mSWI/SNF family complex abundance and chromatin-level gene regulatory functions and suggest therapeutic utility of mSWI/SNF complex small molecule inhibitors in dedifferentiated endometrial carcinoma and other cBAF-disrupted cancer types.

  Study EGAS50000001004

• Ten colorectal cancer patients with locally advanced primary tumors who underwent primary tumor resection following neoadjuvant chemotherapy (NAC).

  Background We aim to investigate the utility of serial gene mutation tracking for locally advanced CRC in those who underwent curative resection following neoadjuvant chemotherapy. Methods We prospectively collected 10 locally advanced CRC cases for which curative resection was performed following preoperative neoadjuvant chemotherapy. Tissues from the primary tumour, distant metastatic tumours, and blood plasma were obtained during serial treatment. Comprehensive mutation analysis of 47 cancer-associated genes was performed using a pre-designed gene panel and next-generation sequencing. Results All cases showed a partial response to neoadjuvant chemotherapy, and pathological R0 resection was accomplished. In primary tumours, non-synonymous mutations were detected at between 1 and 14 sites before chemotherapy and at between 1 and 2 sites after. Founder mutations were precisely detected in blood plasma and metastatic tumours during longitudinal treatment. Conclusions Serial mutational analysis indicated that subclonal selection occurs during chemotherapy and that plasma can substitute for tumourous tissue in mutational analysis for drug selection and treatment decisions.

  Study JGAS000222

• Targeted sequencing (paired) of HR genes in primary and metastatic patient-derived xenografts (PDXs) of colorectal cancer (CRC)

  Chemotherapy is the standard-of-care treatment for metastatic colorectal cancer (mCRC) and benefits some patients, but what distinguishes responders from non-responders is unclear. In this study, we leveraged a comprehensive collection of 69 molecularly annotated patient-derived xenografts to uncover functional predictors of response to 5-FU and irinotecan combination therapy (FOLFIRI) in mCRC. Genetic analyses revealed that treatment sensitivity was marked by genomic scars indicative of BRCAness, suggesting homologous recombination (HR) deficiency as a key determinant. Accordingly, we surveyed a manually curated panel of 44 genes with a documented role in HR for the potential presence of pathogenic mutations. We did not observe a specific enrichment of HR gene mutations based on response to FOLFIRI. This result, combined with the absence of widespread biallelic inactivation of the analyzed genes and the predominance of mutations categorized as variants of unknown significance, suggests that FOLFIRI sensitivity is not primarily governed by underlying mutations in HR genes responsible for mitigating the genotoxic effects of this therapeutic regimen.

  Study EGAS50000000075

• Fragmentomics Uncover Non-Mutational HRD Features

  Homologous recombination deficiency (HRD) is a key biomarker in prostate cancer (PCa), predicting response to PARP inhibitors and platinum-based therapies. However, current diagnostics often rely solely on BRCA1/2 mutations or genomic scars, missing cases driven by other mechanisms. Tissue-based testing is further limited by tumor heterogeneity and biopsy challenges in metastatic bone disease. Here, we applied a comprehensive multimodal approach to assess HRD in 106 advanced PCa patients using circulating tumor DNA (ctDNA). This included targeted sequencing of homologous recombination repair (HRR) genes, low-pass WGS for genomic instability (sHRD), WES for mutational signatures, and cfDNA fragmentomics and chromatin accessibility profiling. BRCA2 was the most frequently altered gene, often co-occurring with PTEN loss. High sHRD scores correlated with BRCA2/RB1 loss, somatic copy number alterations, and poor survival. HRD tumors showed enrichment of SBS3/ID6 signatures, altered fragment lengths, and reduced accessibility at zinc finger transcription factor sites. These results support ctDNA-based multimodal profiling as a non-invasive strategy for HRD detection and stratification.

  Study EGAS00001008190

• DCIS fresh frozen fragmentomics dataset

  Ductal carcinoma in situ (DCIS) is a non-obligate precursor lesion of breast cancer (BC). Often detected by mammography, most cases are managed through surgical and/or radiotherapy approaches. Today, it is not possible to predict which patients will progress to invasive disease. Here, we evaluated high-depth whole-genome sequenced (WGS) DCIS, enriched for highgrade clinical lesions, to understand whether deep WGS could reveal biological insights and/or personalized therapeutic vulnerabilities that may be targetable. We find genomic locations that are likely susceptible to producing the initiating lesion for structural variations (SVs) prone to subsequent evolution, termed SHOREs (Susceptibility HOtspots for Rearrangements and ongoing Evolution). We additionally highlight individualized therapeutic potential that would otherwise not be appreciable without WGS. We posit that holistic WGS profiling could offer a more precise stratification approach, discerning higher-risk cases for prospective clinical studies on personalized therapies, from truly low-risk cases suitable for active monitoring. To substantiate our WGS findings, we also performed RNAseq on the same samples, this EGA study contains the RNAseq data.

  Study EGAS50000001475

• DERMATLAS__Hidradenoma_papilliferum_WES

  Virtually no other tumour type is associated with so many different forms as skin cancer. Histologically, tumours of the skin may arise from epithelium, including epidermis, hair follicle, sebaceous or sweat gland, melanocytes, dermal-associated mesenchymal structures or tissue resident immune cells, making for a diversity of clinical presentations. Importantly, many skin tumour types have an extremely poor prognosis. Many skin tumour subtypes have never undergone molecular profiling, or if they have, targeted sequencing has been used and the number of cases analyzed has been so limited that deriving firm conclusions about the profile of driver genes, DNA mutational signatures and germline alleles has not been possible For 70 key skin tumour subtypes defined by the World Health Organization, that have not undergone extensive genetic analysis previoulsy, we propose to perform whole exome and transcriptome sequencing, from a range of body sites, to build a genomic atlas of dermatological tumours, including detailed maps of SNVs, copy number alterations, genome-wide methylation and expression profiles. The cases in this cohort are hidradenoma papilliferums.

  Study EGAS00001005714

• Integrated genomic analyses identify ARID1A and ARID1B alterations in the childhood cancer neuroblastoma

  Neuroblastomas are tumors of peripheral sympathetic neurons and are the most common solid tumor in children. To determine the genetic basis for neuroblastoma we performed whole-genome sequencing (6 cases), exome sequencing (16 cases), genome-wide rearrangement analyses (32 cases), and targeted analyses of specific genomic loci (40 cases) using massively parallel sequencing. On average each tumor had 19 somatic alterations in coding genes (range, 3-70). Among genes not previously known to be involved in neuroblastoma, chromosomal deletions and sequence alterations of chromatin remodeling genes, ARID1A and ARID1B, were identified in 8 of 71 tumors (11%) and were associated with early treatment failure and decreased survival. Using tumor-specific structural alterations, we developed an approach to identify rearranged DNA fragments in sera, providing personalized biomarkers for minimal residual disease detection and monitoring. These results highlight dysregulation of chromatin remodeling in pediatric tumorigenesis and provide new approaches for the management of neuroblastoma patients.Data Provider: Johns Hopkins Sidney Kimmel Comprehensive Cancer Center (SKCCC)

  Study EGAS00001000369

• Ovarian cancer organoid biobank

  Ovarian cancer (OC) is a heterogeneous disease usually diagnosed at a late stage. Experimental in vitro models that faithfully capture the hallmarks and tumor heterogeneity of OC are limited and hard to establish. We present a novel protocol that enables efficient derivation and long-term expansion of OC organoids. Utilizing this protocol, we have established 56 organoid lines from 32 patients, representing the spectrum of ovarian neoplasms, including non-malignant borderline tumors, as well as mucinous, clear-cell, endometrioid, low- and high-grade serous carcinomas. OC organoids recapitulate histological and genomic features of the pertinent lesion from which they were derived, illustrating intra- and inter-patient heterogeneity, and can be genetically modified. We show that OC organoids can be used for drug screening assays and capture different tumor subtype responses to the gold standard platinum-based chemotherapy, including acquisition of chemoresistance in recurrent disease. Finally, OC organoids can be xenografted, enabling in vivo drug sensitivity assays. Taken together, this demonstrates their potential application for research and personalized medicine.

  Study EGAS00001003073

• Drug screening and whole genome sequencing of primary cells and cell lines from ovarian cancer patients to associate genomic aberrations with in vitro drug sensitivities

  Identifying drugs for cancers with poor prognosis like ovarian cancer (OC) is hindered by inappropriate cell models and the limitations of current viability assays. We developed an automated confocal microscopy-based live cell assay (DeathPro) that robustly de-convolves cell death and proliferation over time by employing a specific image processing strategy. Using DeathPro, we screened nine OC patient-derived cell lines and one normal cell line (HOSEpiC) with 22 drugs or combinations. Whole genome was performed to analyze if the cell lines harbor OC-typical genomic aberrations and to relate genomic features to drug sensitivities. Commonly observed alterations in OC patients like TP53 mutations and MYC or PI3KCA amplifications were absent in the normal cell line but frequently detected in the OC cell lines. Moreover, genome-derived homologous recombination deficiency (HRD) scores of the OC cell lines correlated with their responses to carboplatin, olaparib and DNA demethylation drugs. Overall, we propose an imaging-based platform to guide drug development and genome-drug sensitivity analysis.

  Study EGAS00001002239