12137 results for "cancer rna-seq"

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• PCR-free shallow whole genome sequencing for chromosomal copy number detection from plasma of cancer patients is an efficient alternative to the conventional PCR-based approach

  Somatic copy number alterations (SCNAs) can be detected in tumor cell-free DNA (cfDNA) by shallow whole genome sequencing (sWGS). Polymerase chain reaction (PCR) is typically included in library preparations, but a PCR-free method could be an effective alternative for research and diagnostics. Peripheral blood samples (n=22) were collected in EDTA-containing tubes from non-small cell lung cancer patients (n=10) and healthy donors (n=12). PCR and PCR-free library preparations underwent sWGS and the following metrics were compared: mapping quality, proportion of duplicate reads, genome coverage, sequencing read length and copy number profiles. The PCR-free method was further evaluated on archived plasma samples (n=33) of varying pre-analytical quality collected in EDTA or lithium heparin tubes. Archived samples were from acute myeloid leukaemia (n=15) and B-cell lymphoma (n=18) patients. The percentage of unique reads was significantly higher for the 22 samples analysed by PCR-free (95.7%) compared to PCR (84%). PCR-free libraries from 33 archived samples produced data of a comparable quality, with 95.4% unique reads. All other evaluated metrics were highly comparable for PCR and PCR-free library preparations. We conclude that SCNA detection can be performed by PCR-free sWGS on cfDNA from cancer patients and is feasible for diagnostic and archival plasma collected in EDTA- or lithium heparin-containing tubes. Our results pave the way for an automated cfDNA workflow for cancer plasma samples.

  Study EGAS00001004692

• Transcriptional profiling of ovarian tumours and cell lines

  Purpose: Endogenous retroviruses (ERVs) play a role in a variety of biological processes, including embryogenesis and cancer. DNA methyltransferase inhibitors (DNMTi)-induced ERV expression triggers interferon responses in ovarian cancer cells via the viral sensing machinery. Baseline expression of ERVs also occurs in cancer cells, though this process is poorly understood and previously unexplored in epithelial ovarian cancer (EOC). Here, the prognostic and immunomodulatory consequences of baseline ERV expression was assessed in EOC. Experimental Design: ERV expression was assessed using EOC transcriptional data from TCGA and from an independent cohort (HH), as well as from untreated or DNMTi-treated EOC cell lines. LASSO logistic regression defined an ERV expression score to predict patient prognosis. Immunohistochemistry (IHC) was conducted on the HH cohort. Combination of DNMTi treatment with γδ T cells was tested in vitro, using EOC cell lines and patient-derived tumor cells. Results: ERV expression was found to define clinically relevant subsets of EOC patients. An ERV prognostic score was successfully generated in TCGA and validated in the independent cohort. In EOC patients from this cohort, a high ERV score was associated with better survival (log-rank p=0.0009) and correlated with infiltration of CD8+PD1+ T cells (r=0.46, p=0.0001). In vitro, baseline ERV expression dictates the level of ERV induction in response to DNMTi. Manipulation of ERV expression by DNMTi resulted in improved EOC cell killing by cytotoxic immune cells. Conclusions: These findings uncover the potential for baseline ERV expression to robustly inform EOC patient prognosis, influence tumor immune infiltration and affect anti-tumor immunity.

  Study EGAS00001004814

• Phylogenetic analysis of treatment-naive metastases using whole exome and genome sequencing data

  Metastases are responsible for the majority of cancer related deaths and are often difficult to treat successfully. Even for metastases that occur subsequent to treatment, we do not know whether such relapsing metastases were originally heterogeneous or if the observed heterogeneity is a consequence of therapy. Given that treatment can influence evolutionary dynamics by selecting resistant clones, imposing bottlenecks on cancer cell populations, and even inducing novel somatic mutations, characterizing the prior standing variation among metastases remains an important goal to predict initial therapeutic response. To quantify the heterogeneity at clinical presentation of advanced disease, we surveyed the literature for patients in which at least two treatment-naïve metastases underwent genome/exome-wide sequencing. Across all cancer types surveyed, only 18 subjects were found to fulfill this requirement. Including previously unpublished data from two subjects, we analyzed data of 74 untreated metastases and inferred cancer phylogenies. Putative driver gene mutations were acquired at a 2-fold higher rate on the trunk of all metastases than on branches. Mutations in driver genes along the trunk were strongly enriched for predicted functional consequences. Using a stochastic mathematical model, we find that driver gene heterogeneity among metastases mostly occurs in slowly growing cancers for highly advantageous driver gene mutations. Seeding efficiency only weakly affects the heterogeneity among metastases. These results explain why functional driver gene heterogeneity is uncommon in advanced disease prior to treatment, thus providing optimism for future therapies that depend on mutations across metastases.

  Study EGAS00001002777

• Whole Exome Sequencing data of six chRCC tumors corresponding to three patients

  Mammalian target of rapamycin (mTOR) is a central regulator of mammalian metabolism and physiology. Aberrant hyperactivation of the mTOR pathway promotes tumor growth and metastasis, and can also promote tumor resistance to chemotherapy and cancer drugs; this makes mTOR an attractive cancer therapeutic target. mTOR inhibitors have been approved to treat cancer; however, the mechanisms underlying drug sensitivity remain poorly understood. Here, whole exome sequencing of three chromophobe renal cell carcinoma (chRCC) patients with exceptional mTOR inhibitor sensitivity revealed that all three patients shared somatic mutations in the deubiquitinase USP9X. The clonal characteristics of the mutations, which were amassed by studying multiple patients’ primary and metastatic samples from various years, together with the low USP9X mutation rate in unselected chRCC series, reinforced a causal link between USP9X and mTOR inhibitor sensitivity. Rapamycin treatment of USP9X-depleted HeLa and renal cancer 786-O cells, along with the pharmacological inhibition of USP9X, confirmed that this protein plays a role in patients’ sensitivity to mTOR inhibition. USP9X was not found to exert a direct effect on mTORC1, but subsequent ubiquitylome analyses identified p62 as a direct USP9X target. Increased p62 ubiquitination and the augmented rapamycin effect upon bortezomib treatment, together with the results of p62 and LC3 immunofluorescence assays, suggested that dysregulated autophagy in USP9X-depleted cells can have a synergistic effect with mTOR inhibitors. In summary, we show that USP9X constitutes a potential novel marker of sensitivity to mTOR inhibitors in chRCC patients, and represents a clinical strategy for increasing the sensitivity to these drugs.

  Study EGAS00001007104

• The University of Hong Kong Intestinal Metaplasia Organoids Study

  Background: Gastric intestinal metaplasia (IM) is a pre-cancerous stage spanning a morphological spectrum that is poorly represented by human cell line models. Objective: We aim to establish and characterize human IM cell models to better understand IM progression along the cancer spectrum. Design: A large human gastric IM organoid (IMO) cohort (n=28), their clonal derivatives and normal gastric organoids (n=42) for comparison were established. Comprehensive multi-omics profiling and functional characterization were performed. Results: Single-cell transcriptomes revealed IMO cells spanning a spectrum from hybrid gastric/intestinal to advanced intestinal differentiation. Their lineage trajectories connected different cycling and quiescent stem and progenitors, highlighting differences in gastric to IM transition and the potential origin of IM from STMN1 cycling isthmus stem cells. Hybrid IMOs showed impaired differentiation potential, high lineage plasticity beyond gastric or intestinal fates, and reactivation of a fetal gene program. Cell populations in gastric IM and cancer tissues were highly similar to those derived from IMOs and exhibited a fetal signature. Genomically, IMOs showed elevated mutation burden, frequent chromosome 20 gain, and epigenetic de-regulation of many intestinal and gastric genes. Functionally, IMOs were FGF10 independent and showed downregulated FGFR2. Several IMOs exhibited a cell-matrix adhesion independent (CMi) subpopulation that displayed chromosome 20 gain but lacked key cancer driver mutations, potentially representing the earliest neoplastic precursor of IM-induced gastric cancer. Conclusions: Overall, our IM organoid biobank captured the heterogeneous nature of IM, revealing mechanistic insights on IM pathogenesis and progression, offering an ideal platform for studying early gastric neoplastic transformation and chemoprevention.

  Study EGAS00001007899

• Immunogenomics of Malignant Brain Tumors

  We performed systematic and comprehensive multi-sector immunogenomic analyses on 93 samples from a cohort of 30 patients with primary or recurrent gliomas or metastatic brain tumors, representing the largest cohort of these brain cancers studied spatially to date. For each patient, we characterized multiple spatially distinct regions using whole-exome (WES), custom capture validation, RNA, and TCR-sequencing. Our findings underscore the significant differences in clonal architecture between gliomas and metastatic brain tumors which translates into distinct neoantigen landscapes and, in turn, tumor infiltrating T cell clonotypic diversity. These data therefore provide high resolution insights into the immunogenomic landscapes within malignant brain tumors which may inform tumor-specific therapeutic approaches.

  Study phs002612

• Genomic landscape of Neutrophilic Leukemias of Ambiguous Diagnosis

  Chronic neutrophilic leukemia (CNL), atypical chronic myeloid leukemia (aCML), and unclassified myelodysplastic syndrome/myeloproliferative neoplasms (MDS/MPN-U) are a group of rare, heterogeneous myeloid disorders. There is strong morphologic resemblance amongst these distinct diagnostic entities as well as lack of specific molecular markers and limited understanding of disease pathogenesis, which has made their diagnosis challenging. Treatment has remained empirical, resulting in dismal outcomes. We, therefore, performed whole exome and RNA-sequencing on a cohort of over 100 cases of these rare hematologic malignancies and present the most complete survey of the genomic landscape of these diseases to date. [Abstract from manuscript currently under review so copyright not yet determined]

  Study phs001799

• Developing Biomarkers Incorporating High Throughput RNA, DNA, Small RNA Sequencing and Protein Expression in Inflammatory Bowel Disease Using Formalin-Fixed, Paraffin-Embedded (FFPE) Tissue Samples

  This study included pediatric patients with suspected inflammatory bowel disease (IBD) who underwent endoscopy between 2008 and 2012. This included 101 colonic tissue samples and 100 ileal tissue samples. Biopsies were obtained at the time of diagnosis, and patients were followed for a mean of 6 years to record clinical characteristics. These included baseline characteristics, such as age of diagnosis and initial Montreal classification, as well as outcomes, such as stricturing or fistulizing complications, disease remission, or progression to surgery.Genes with significant results in the non-IBD vs CD comparison in colonic tissue are listed in the "Links to Related Genes" section of this page.

  Study phs003156

• Single Cell Analysis of Psoriasis Resolution following IL-23 Blockade

  Full-thickness skin biopsies were obtained from five individuals with severe psoriasis who were receiving risankizumab treatment. Skin biopsies were taken from lesional and non-lesional sites at baseline, and from lesional sites at day 3 and day 14 of therapy. All biopsies were taken from site-matched areas on the lower back/buttocks. Single-cell RNA sequencing was performed using a 10x Genomics platform. Myeloid and fibroblast populations showed the strongest change in gene expression after 3 days. An inflammatory, transient WNT5A+/IL24+ fibroblast state was identified, which was elevated in abundance in lesional skin versus non lesional skin, and decreased after 14 days of treatment. R1 and R2 FASTQs files are available.

  Study phs003351

• Depth of Response Correlates with Improved Outcomes for Early Interception in a High-Risk Smoldering Multiple Myeloma Clinical Trial Using the Combination of Ixazomib, Lenalidomide, and Dexamethasone

  Early treatment of patients with high-risk smoldering myeloma (HRSMM) has been shown to delay progression to multiple myeloma (MM), but not all patients respond well. Identifying biological predictors of response and resistance to treatment can help optimize treatment selection for patients and improve outcomes. Here, we investigate tumor and immune biomarkers of response to ixazomib, lenalidomide, and dexamethasone treatment (I-PRISM study) that can be measured at diagnosis. We performed single-cell RNA sequencing (scRNAseq), coupled with B cell receptor and T cell receptor sequencing, on CD138+ tumor and CD138- immune cells, respectively, from the bone marrow of 20 patients enrolled in the I-PRISM study.

  Study phs003827