14977 results for "cancer studies using rna-seq"

in 178.60 milliseconds.

• Dynamics of checkpoint receptors in γδ T cell subsets are associated with clinical responses during anti-PD-1 immunotherapies

  Gamma delta (γδ) T cells are innate-like lymphocytes with potent anti-tumor properties. Herein, we show that immune checkpoint receptors (ICRs) display differential expression and regulation by the JAK-STAT pathway in Vδ1 and Vδ2 cells and identify constitutive (e.g. TIGIT, PD-1) and inducible (e.g. TIM-3, LAG-3, CTLA-4) ICRs. In melanoma, all γδ T cell subsets downregulated AP-1 transcription factors, but Vδ1 cells specifically expressed high levels of ICR, TOX and inhibitory killer Ig-like receptor (KIR) transcripts, reminiscent of exhaustion. However, patient-derived cells were functionally competent, although induction of LAG-3 and CTLA-4 was impaired. During anti-PD-1 monotherapy, Vδ1 cells specifically bound high levels of therapeutic antibody but only in patients who responded to treatment, revealing a potential new prognostic marker for evaluating the efficacy of IC blockade (ICB) therapy. Finally, expression of KIR genes in Vδ1 cells was downregulated in response to successful ICB therapy. Collectively, our data indicate an intricate relationship between ICRs and γδ T cells and reveal novel approaches by which these cells can be harnessed in order to discern or improve cancer immunotherapy.

  Study EGAS50000001270

• Distinct portrayal of lesions in synchronous multifocal lung adenocarcinoma revealed by genome sequencing

  Distinguishing multiple primary lung cancers in the synchronous multifocal intrapulmonary lesions has important significance on clinical staging and therapeutic decision. To investigate genomic aberration profiles, we applied whole genome and whole exome sequencing, and microarray-based comparative genomic hybridization on 15 intrapulmonary tumors derived from six patients with synchronous multifocal lung cancers having similar histological diagnosis. Any pair of intrapulmonary tumors in a single patient, which shared the identical genetic background and environment, showed an extinctive heterogeneity between each other. Phylogenetic relationship analysis indicated an independently branched evolution among all the tumors, suggesting they were multiple primary lung cancers. EGFR or KRAS mutations were found in 7 or 3 out of the 15 tumors, from 3 or 2 patients, respectively. Somatic mutational heterogeneity of these two genes in a single patient was also observed. Our analysis indicates genomic aberration profiling is valuable for identification of multiple primary lung cancer, especially when high histopathological concordance was observed between lesions. We also suggest a thoroughly molecular diagnosis against therapeutic target genes should be taken for each accessible nodule before making a plan for adjuvant therapy.

  Study EGAS00001001572

• Whole genome sequencing of Ewings Sarcoma

  Sarcomas are cancers of the bone and soft tissue often defined by their gene fusions. However, the timing, context, and processes by which these pathogenic fusions arise are unknown. We explored this in Ewing sarcoma, a cancer driven by EWSR1-ETS fusions, with very few cooperating mutations. Combining whole-genome sequencing with enhanced informatics, we found that the EWSR1-ETS fusion arose from striking rearrangement clusters in 42% of cases (52/124). Notably, these were organized in loops that universally contained the fusion at their center, while also weaving up to 18 genes together with it. We found the same pattern of rearrangements in three additional types of sarcoma. From these data, we define a new signature for sarcoma fusions that precedes other somatic changes, in the earliest replicating DNA of the genome. This dramatic, sudden process impinges on many genes – generating multiple coding changes that profoundly affect the transcriptome, with the disease-defining gene fusion at its core. These rearrangement loops emerge in an early ES clone from which both the primary tumor and the lethal relapse emerged, and then evolved in parallel until clinically detected.

  Study EGAS00001003385

• Comprehensive characterization of cell-free tumor DNA in plasma and urine of patients with renal tumors

  Cell-free tumour-derived DNA (ctDNA) allows non-invasive monitoring of various cancers but its utility in renal cell cancer (RCC) has not been well established. A combination of untargeted and targeted sequencing methods, applied to two independent cohorts of patients (n=90) with various renal tumour subtypes, were used to determine ctDNA content in plasma and urine. Our data revealed lower plasma ctDNA levels in RCC relative to other cancers, with untargeted detection of ~33% for both cohorts. A highly sensitive personalised approach, applied to plasma and urine from select patients (n=22), improved detection to ~50%, including in patients with early stage and even benign lesions. A machine-learning based model, applied to untargeted data, predicted this detection, potentially offering a means of triaging patient samples for personalised analysis. We observed that plasma, and for the first time, urine ctDNA may better represent tumour heterogeneity than a single tissue biopsy. Longitudinal sampling of >200 plasma samples revealed that ctDNA can track disease course. These data highlight low ctDNA levels in RCC but indicate potential clinical utility provided improvement in isolation and detection approaches.

  Study EGAS00001003530

• Phosphoproteomics adds value to treatment recommendations in molecular tumor boards

  Precision oncology approaches employing genomics-guided targeted therapies for individual patients have provided significant survival benefits in several cancer types. However, low response rates in most solid malignancies, many patients without actionable genomic lesions, and increasing evidence that non-genomic mechanisms may play an important role in tumors indicate that genomics alone is often insufficient to inform and guide the clinical care of patients. Here, we show for the first time that comprehensive (phospho)proteome profiling is feasible and informative in a real-world prospective precision oncology setting. We developed a novel tumor pathway activity (TUPAC) scoring methodology that provides a holistic perspective on dysregulated receptor tyrosine kinase (RTK) signaling in individual patients. Based on 919 tumor tissue profiles of patients enrolled in the national NCT/DKTK MASTER study and the INFORM registry trial, we illustrate how TUPAC scoring can be used to uncover individual tumor biology in rare cancers and demonstrate that TUPAC methodology identifies EGFR-driven sarcomas despite the absence of genetic EGFR alterations. Overall, our work demonstrates the utility of the additional phosphoproteome data layer to enhance therapeutic recommendations in molecular tumor boards.

  Study EGAS00001007891

• Low and variable tumor reactivity of the intratumoral TCR repertoire in human cancers

  Infiltration of human cancers by T cells is generally interpreted as a sign of immune recognition, and there is a growing effort to reactivate dysfunctional T cells at such tumor sites. However, these efforts only have value if the intratumoral T cell receptor (TCR) repertoire of such cells is intrinsically tumor-reactive, and this has not been established in an unbiased manner for most human cancers. To address this issue, we analyzed the intrinsic tumor-reactivity of the intratumoral TCR repertoire of CD8+ T cells in ovarian and colorectal cancer – two tumor types for which T cell infiltrates form a positive prognostic marker. Data obtained demonstrate that a capacity to recognize autologous tumor is limited to approximately 10% of intratumoral CD8+ T cells. Furthermore, in two out of four patient samples tested, no tumor-reactive TCRs were identified, despite infiltration of their tumors by T cells. These data indicate that the intrinsic capacity of intratumoral T cells to recognize adjacent tumor tissue can be rare and variable, and suggest that clinical efforts to reactivate intratumoral T cells will benefit from approaches that simultaneously increase the quality of the intratumoral TCR repertoire.

  Study EGAS00001003119

• Clonal relationships of ductal carcinoma in situ and recurrent invasive breast cancers defined by genomic analysis

  Ductal Carcinoma In Situ (DCIS) is the most common form of pre-invasive breast cancer and despite treatment a small fraction (5-10%) of DCIS patients present with invasive disease many years later. A fundamental biologic question is whether the invasive disease recurring in the same breast is established by tumor cells in the initial DCIS or represents new unrelated disease. To address this question, we performed genomic analyses on the initial pure DCIS lesion and paired invasive recurrent tumors in 95 patients together with single cell DNA sequencing in a subset of cases. Our data shows that in 75% the invasive recurrence was clonally related to the initial DCIS, suggesting that the tumor cells were not eliminated during the initial treatment with surgery +/- radiotherapy. Surprisingly however, 18% were clonally unrelated to the DCIS, representing new independent lineages, and 7% of cases were ambiguous. Our findings show that although DCIS is often the precursor of invasive recurrence, a significant fraction of invasive recurrences are unrelated to the initial DCIS. This knowledge is essential for accurate risk evaluation of DCIS treatment de-escalation strategies and the identification of predictive biomarkers.

  Study EGAS00001005784

• SS18-SSX-mediated hijacking of BAF complexes drives synovial sarcoma

  Synovial sarcoma (SS) is defined by a recurrent t(x;18) chromosomal translocation, which produces the hallmark SS18-SSX oncogenic fusion. Incorporation of SS18-SSX into BAF complexes renders BAF complexes aberrant in two distinct manners: the addition of 78aa of SSX onto SS18, and concomitant loss of BAF47 assembly. However, the importance and functional contributions of each of these perturbations on BAF complex targeting and gene expression regulation remain unclear. Here we use an integrative set of genomic approaches in human cancer cell lines and primary tumor samples to define the mechanistic consequences of the SS18-SSX fusion oncoprotein. We find that SS18-SSX hijacks BAF complexes to broad polycomb domains to activate bivalent genes, driving a unique gene expression program distinct from other loss-of-function BAF complex malignancies. Importantly, restoration of BAF47 rescues enhancer activation but is dispensable for proliferative arrest in cell lines. These results demonstrate that gain-of-function SS18-SSX-mediated BAF complex targeting and gene activation is the driving event in SS, and present a mechanism by which distinct functions of BAF complexes can be co-opted to drive oncogenesis.

  Study EGAS00001002920

• Target gene sequencing for human normal endometrial glands

  To elucidate the timing and mechanism of the clonal expansion of somatic mutations in cancer-associated genes in the normal endometrium, we conducted target sequencing of 112 genes for 1,298 endometrial glands and matched blood samples from 36 women. By collecting endometrial glands from different parts of the endometrium, we showed that multiple glands with the same somatic mutations occupied substantial areas of the endometrium. The 112 genes are as follows: ABCC1, ACRC, ANK3, ARHGAP35, ARID1A, ARID5B, ATCAY, ATM, ATR, BARD1, BCOR, BRCA1, BRCA2, BRD4, BRIP1, CAMTA1, CDC23, CDYL, CFAP54, CHD4, CHEK1, CHEK2, CTCF, CTNNB1, CUX1, DGKA, DISP2, DYNC2H1, EMSY, FAAP24, FAM135B, FAM175A, FAM65C, FANCA, FANCB, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCI, FANCL, FANCM, FAT1, FAT3, FBN2, FBXW7, FGFR2, FRG1, GPR50, HEATR1, HIST1H4B, HNRNPCL1, HOOK3, KIAA1109, KIF26A, KMT2B, KMT2C, KRAS, LAMA2, LRP1B, MLH1, MON2, MRE11A, MSH2, MSH6, MTOR, NBN, PALB2, PHEX, PIK3CA, PIK3R1, PLXNB2, PLXND1, PMS2, POLE, POLR3B, PPP2R1A, PTEN, PTPN13, RAD50, RAD51, RAD51B, RAD51C, RAD51D, RAD52, RAD54B, RAD54L, RICTOR, SACS, SIGLEC9, SLC19A1, SLX4, SPEG, STT3A, TAF1, TAF2, TAS2R31, TFAP2C, TNC, TONSL, TP53, TTC6, UBA7, VNN1, WT1, XIRP2, ZBED6, ZC3H13, ZFHX3, ZFHX4, ZMYM4.

  Study EGAS00001005914

• Allele-specific expression of GATA2 due to epigenetic dysregulation in double mutated CEBPA AML

  Transcriptional deregulation is a central event in the development of acute myeloid leukemia (AML). To identify potential disturbances in gene regulation, we conducted an unbiased screen of allele-specific expression (ASE) in 209 AML cases. The gene encoding GATA binding protein 2 (GATA2) displayed ASE more often than any other myeloid or cancer-related gene. GATA2 ASE was strongly associated with CEBPA double mutations (CEBPA DM), with 95% of cases presenting GATA2 ASE. In CEBPA DM AML with GATA2 mutations, the mutated allele was preferentially expressed. We found that GATA2 ASE is a somatic event lost in complete remission, supporting the notion that it plays a role in CEBPA DM AML. Acquisition of GATA2 ASE involved silencing of one allele via promoter methylation, compensated by overactivation of the other allele, thereby preserving expression levels. Notably, promoter methylation was also lost in remission together with GATA2 ASE. In summary, we propose that GATA2 ASE is acquired by epigenetic mechanisms and is a prerequisite for the development of AML with CEBPA DM. This finding constitutes a novel example of an epigenetic hit cooperating with a genetic hit in the pathogenesis of AML.

  Study EGAS00001004684