Identification of pancreatic cancer-specific protease substrates for protease-dependent targeted delivery.

Pancreatic ductal adenocarcinoma (PDAC) presents significant challenges due to the inadequacy of existing chemotherapeutics, which often result in toxicity-dependent dose limitations and premature cessation of therapy. Targeted delivery of therapeutic molecules offers a promising solution. Given that PDAC is marked by a desmoplastic reaction with extensive aberrant protease activity, protease-dependent targeted delivery could minimize off-target toxicities and is of increasing interest.

Identifying colorectal cancer-specific vulnerabilities in the Wnt-driven long non-coding transcriptome.

Background: Aberrant Wnt pathway activation is a key driver of colorectal cancer (CRC) and is essential to sustain tumour growth and progression. Although the downstream protein-coding target genes of the Wnt cascade are well known, the long non-coding transcriptome has not yet been fully resolved.

Objective: In this study, we aim to comprehensively reveal the Wnt-regulated long non-coding transcriptome and exploit essential molecules as novel therapeutic targets.

Hypoxia Abrogates Tumor-Suppressive Activities of C/EBPδ in Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease with a low 5-year survival rate of only 13%. Despite intense research efforts, PDAC remains insufficiently understood. In part, this is attributed to opposing effects of key players being unraveled, including the stroma but also molecules that act in a context-dependent manner.

Transcriptome-based classification to predict FOLFIRINOX response in a real-world metastatic pancreatic cancer cohort.

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at metastatic stage and typically treated with fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX). Few patients benefit from this treatment. Molecular subtypes are prognostic in particularly resectable PDAC and might predict treatment response.

Exploiting a subtype-specific mitochondrial vulnerability for successful treatment of colorectal peritoneal metastases.

Peritoneal metastases (PMs) from colorectal cancer (CRC) respond poorly to treatment and are associated with unfavorable prognosis. For example, the addition of hyperthermic intraperitoneal chemotherapy (HIPEC) to cytoreductive surgery in resectable patients shows limited benefit, and novel treatments are urgently needed. The majority of CRC-PMs represent the CMS4 molecular subtype of CRC, and here we queried the vulnerabilities of this subtype in pharmacogenomic databases to identify novel therapies.

Iron-responsive element of Divalent metal transporter 1 (Dmt1) controls Notch-mediated cell fates.

Notch receptor activation is regulated by the intramembrane protease γ-secretase, which cleaves and liberates the Notch intracellular domain (Nicd) that regulates gene transcription. While γ-secretase cleavage is necessary, we demonstrate it is insufficient for Notch activation and requires vesicular trafficking. Here, we report Divalent metal transporter 1 (Dmt1, Slc11A2) as a novel and essential regulator of Notch signalling.

Systematic multi-omics cell line profiling uncovers principles of Ewing sarcoma fusion oncogene-mediated gene regulation.

Ewing sarcoma (EwS) is characterized by EWSR1-ETS fusion transcription factors converting polymorphic GGAA microsatellites (mSats) into potent neo-enhancers. Although the paucity of additional mutations makes EwS a genuine model to study principles of cooperation between dominant fusion oncogenes and neo-enhancers, this is impeded by the limited number of well-characterized models. Here we present the Ewing Sarcoma Cell Line Atlas (ESCLA), comprising whole-genome, DNA methylation, transcriptome, proteome, and chromatin immunoprecipitation sequencing (ChIP-seq) data of 18 cell lines with inducible EWSR1-ETS knockdown.

Estrogen-related receptor alpha drives mitochondrial biogenesis and resistance to neoadjuvant chemoradiation in esophageal cancer.

Neoadjuvant chemoradiotherapy (nCRT) improves outcomes in resectable esophageal adenocarcinoma (EAC), but acquired resistance precludes long-term efficacy. Here, we delineate these resistance mechanisms. RNA sequencing on matched patient samples obtained pre-and post-neoadjuvant treatment reveal that oxidative phosphorylation was the most upregulated of all biological programs following nCRT.

Modulation of macrophage inflammatory function through selective inhibition of the epigenetic reader protein SP140.

Background: SP140 is a bromodomain-containing protein expressed predominantly in immune cells. Genetic polymorphisms and epigenetic modifications in the SP140 locus have been linked to Crohn's disease (CD), suggesting a role in inflammation.

Results: We report the development of the first small molecule SP140 inhibitor (GSK761) and utilize this to elucidate SP140 function in macrophages.

Defects in 8-oxo-guanine repair pathway cause high frequency of C > A substitutions in neuroblastoma.

Neuroblastomas are childhood tumors with frequent fatal relapses after induction treatment, which is related to tumor evolution with additional genomic events. Our whole-genome sequencing data analysis revealed a high frequency of somatic cytosine > adenine (C > A) substitutions in primary neuroblastoma tumors, which was associated with poor survival. We showed that increased levels of C > A substitutions correlate with copy number loss (CNL) of or Both genes encode DNA glycosylases that recognize 8-oxo-guanine (8-oxoG) lesions as a first step of 8-oxoG repair.

Specific and Sensitive Detection of Neuroblastoma mRNA Markers by Multiplex RT-qPCR.

mRNA RT-qPCR is shown to be a very sensitive technique to detect minimal residual disease (MRD) in patients with neuroblastoma. Multiple mRNA markers are known to detect heterogeneous neuroblastoma cells in bone marrow (BM) or blood from patients. However, the limited volumes of BM and blood available can hamper the detection of multiple markers.

The molecular landscape of ETMR at diagnosis and relapse.

Embryonal tumours with multilayered rosettes (ETMRs) are aggressive paediatric embryonal brain tumours with a universally poor prognosis. Here we collected 193 primary ETMRs and 23 matched relapse samples to investigate the genomic landscape of this distinct tumour type. We found that patients with tumours in which the proposed driver C19MC was not amplified frequently had germline mutations in DICER1 or other microRNA-related aberrations such as somatic amplification of miR-17-92 (also known as MIR17HG).

A NOTCH feed-forward loop drives reprogramming from adrenergic to mesenchymal state in neuroblastoma.

Transition between differentiation states in development occurs swift but the mechanisms leading to epigenetic and transcriptional reprogramming are poorly understood. The pediatric cancer neuroblastoma includes adrenergic (ADRN) and mesenchymal (MES) tumor cell types, which differ in phenotype, super-enhancers (SEs) and core regulatory circuitries. These cell types can spontaneously interconvert, but the mechanism remains largely unknown.

RAS-MAPK Pathway-Driven Tumor Progression Is Associated with Loss of CIC and Other Genomic Aberrations in Neuroblastoma.

Mutations affecting the RAS-MAPK pathway frequently occur in relapsed neuroblastoma tumors, which suggests that activation of this pathway is associated with a more aggressive phenotype. To explore this hypothesis, we generated several model systems to define a neuroblastoma RAS-MAPK pathway signature. Activation of this pathway in primary tumors indeed correlated with poor survival and was associated with known activating mutations in ALK and other RAS-MAPK pathway genes.

Author Correction: The landscape of genomic alterations across childhood cancers.

In this Article, author Benedikt Brors was erroneously associated with affiliation number '8' (Department of Developmental Neurobiology, St Jude Children's Research Hospital, Memphis, Tennessee, USA); the author's two other affiliations (affiliations '3' and '7', both at the German Cancer Research Center (DKFZ)) were correct. This has been corrected online.

The landscape of genomic alterations across childhood cancers.

Pan-cancer analyses that examine commonalities and differences among various cancer types have emerged as a powerful way to obtain novel insights into cancer biology. Here we present a comprehensive analysis of genetic alterations in a pan-cancer cohort including 961 tumours from children, adolescents, and young adults, comprising 24 distinct molecular types of cancer. Using a standardized workflow, we identified marked differences in terms of mutation frequency and significantly mutated genes in comparison to previously analysed adult cancers.

Neuroblastoma is composed of two super-enhancer-associated differentiation states.

Neuroblastoma and other pediatric tumors show a paucity of gene mutations, which has sparked an interest in their epigenetic regulation. Several tumor types include phenotypically divergent cells, resembling cells from different lineage development stages. It has been proposed that super-enhancer-associated transcription factor (TF) networks underlie lineage identity, but the role of these enhancers in intratumoral heterogeneity is unknown.

TERT rearrangements are frequent in neuroblastoma and identify aggressive tumors.

Whole-genome sequencing detected structural rearrangements of TERT in 17 of 75 high-stage neuroblastomas, with five cases resulting from chromothripsis. Rearrangements were associated with increased TERT expression and targeted regions immediately up- and downstream of TERT, positioning a super-enhancer close to the breakpoints in seven cases. TERT rearrangements (23%), ATRX deletions (11%) and MYCN amplifications (37%) identify three almost non-overlapping groups of high-stage neuroblastoma, each associated with very poor prognosis.

Relapsed neuroblastomas show frequent RAS-MAPK pathway mutations.

The majority of patients with neuroblastoma have tumors that initially respond to chemotherapy, but a large proportion will experience therapy-resistant relapses. The molecular basis of this aggressive phenotype is unknown. Whole-genome sequencing of 23 paired diagnostic and relapse neuroblastomas showed clonal evolution from the diagnostic tumor, with a median of 29 somatic mutations unique to the relapse sample.

Newly-derived neuroblastoma cell lines propagated in serum-free media recapitulate the genotype and phenotype of primary neuroblastoma tumours.

Recently protocols have been devised for the culturing of cell lines from fresh tumours under serum-free conditions in defined neural stem cell medium. These cells, frequently called tumour initiating cells (TICs) closely retained characteristics of the tumours of origin. We report the isolation of eight newly-derived neuroblastoma TICs from six primary neuroblastoma tumours and two bone marrow metastases.

OTX2 sustains a bivalent-like state of OTX2-bound promoters in medulloblastoma by maintaining their H3K27me3 levels.

Recent studies showed frequent mutations in histone H3 lysine 27 (H3K27) demethylases in medulloblastomas of Group 3 and Group 4, suggesting a role for H3K27 methylation in these tumors. Indeed, trimethylated H3K27 (H3K27me3) levels were shown to be higher in Group 3 and 4 tumors compared to WNT and SHH medulloblastomas, also in tumors without detectable mutations in demethylases. Here, we report that polycomb genes, required for H3K27 methylation, are consistently upregulated in Group 3 and 4 tumors.

Sequencing of neuroblastoma identifies chromothripsis and defects in neuritogenesis genes.

Neuroblastoma is a childhood tumour of the peripheral sympathetic nervous system. The pathogenesis has for a long time been quite enigmatic, as only very few gene defects were identified in this often lethal tumour. Frequently detected gene alterations are limited to MYCN amplification (20%) and ALK activations (7%).

Joint binding of OTX2 and MYC in promotor regions is associated with high gene expression in medulloblastoma.

Both OTX2 and MYC are important oncogenes in medulloblastoma, the most common malignant brain tumor in childhood. Much is known about MYC binding to promoter regions, but OTX2 binding is hardly investigated. We used ChIP-on-chip data to analyze the binding patterns of both transcription factors in D425 medulloblastoma cells.

OTX2 directly activates cell cycle genes and inhibits differentiation in medulloblastoma cells.

The transcription factor OTX2 has been implicated as an oncogene in medulloblastoma, which is the most common malignant brain tumor in children. It is highly expressed in most medulloblastomas and amplified in a subset of them. To study the role OTX2 has in medulloblastoma we investigated the downstream pathway of OTX2.

Regulation of cell cycle genes and induction of senescence by overexpression of OTX2 in medulloblastoma cell lines.

The transcription factor orthodenticle homeobox 2 (OTX2) has been implicated in the pathogenesis of medulloblastoma, as it is often highly expressed and sometimes amplified in these tumors. Little is known of the downstream pathways regulated by OTX2. We therefore generated MED8A and DAOY medulloblastoma cell lines with doxycycline-inducible OTX2 expression.