Publications by authors named "Ganesh Umapathy"

Neuroblastoma (NB) is a heterogeneous childhood cancer with a slightly higher incidence in boys than girls, with the reason for this gender disparity unknown. Given the growing evidence for the involvement of loss of the Y chromosome (LoY) in male diseases including cancer, we investigated Y chromosome status in NB. Male NB tumor samples from a Swedish cohort, analyzed using Cytoscan HD SNP-microarray, were selected.

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Numerous roles for the Alk receptor tyrosine kinase have been described in , including functions in the central nervous system (CNS), however the molecular details are poorly understood. To gain mechanistic insight, we employed Targeted DamID (TaDa) transcriptional profiling to identify targets of Alk signaling in the larval CNS. TaDa was employed in larval CNS tissues, while genetically manipulating Alk signaling output.

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High-risk neuroblastoma (NB) is a significant clinical challenge. MYCN and Anaplastic Lymphoma Kinase (ALK), which are often involved in high-risk NB, lead to increased replication stress in cancer cells, suggesting therapeutic strategies. We previously identified an ATR (ataxia telangiectasia and Rad3-related)/ALK inhibitor (ATRi/ALKi) combination as such a strategy in two independent genetically modified mouse NB models.

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Tumor cells are hallmarked by their capacity to undergo unlimited cell divisions, commonly accomplished either by mechanisms that activate or through the alternative lengthening of telomeres pathway. Neuroblastoma is a heterogeneous pediatric cancer, and the aim of this study was to characterize telomere maintenance mechanisms in a high-risk neuroblastoma cohort. All tumor samples were profiled with SNP microarrays and, when material was available, subjected to whole genome sequencing (WGS).

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Anaplastic lymphoma kinase (ALK) fusion variants in Non-Small Cell Lung Cancer (NSCLC) consist of numerous dimerizing fusion partners. Retrospective investigations suggest that treatment benefit in response to ALK tyrosine kinase inhibitors (TKIs) differs dependent on the fusion variant present in the patient tumor. Therefore, understanding the oncogenic signaling networks driven by different ALK fusion variants is important.

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Article Synopsis
  • High-risk neuroblastoma (NB) is associated with MYCN amplification and ALK mutations, making treatment challenging and highlighting the need for new therapies.
  • Oncogenes like MYCN and ALK increase replication stress in cancer cells, which can be targeted for treatment; researchers identified the ATR inhibitor BAY1895344 as effective in inhibiting NB cell growth.
  • Combining ATR and ALK inhibitors over two weeks leads to complete tumor regression in mouse models, indicating that ATR inhibition could significantly benefit high-risk NB patients experiencing oncogene-induced replication stress.
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Anaplastic lymphoma kinase (Alk) is an evolutionary conserved receptor tyrosine kinase belonging to the insulin receptor superfamily. In addition to its well-studied role in cancer, numerous studies have revealed that Alk signaling is associated with a variety of complex traits such as: regulation of growth and metabolism, hibernation, regulation of neurotransmitters, synaptic coupling, axon targeting, decision making, memory formation and learning, alcohol use disorder, as well as steroid hormone metabolism. In this study, we used BioID-based in vivo proximity labeling to identify molecules that interact with Alk in the Drosophila central nervous system (CNS).

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Protein-protein interactions (PPIs) play essential roles in Anaplastic Lymphoma Kinase (ALK) signaling. Systematic characterization of ALK interactors helps elucidate novel ALK signaling mechanisms and may aid in the identification of novel therapeutics targeting related diseases. In this study, we used the Mammalian Membrane Two-Hybrid (MaMTH) system to map the phospho-dependent ALK interactome.

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High-risk neuroblastoma (NB) is responsible for a disproportionate number of childhood deaths due to cancer. One indicator of high-risk NB is amplification of the neural MYC (MYCN) oncogene, which is currently therapeutically intractable. Identification of anaplastic lymphoma kinase (ALK) as an NB oncogene raised the possibility of using ALK tyrosine kinase inhibitors (TKIs) in treatment of patients with activating ALK mutations.

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Neuroblastoma is an aggressive childhood cancer arising from sympatho-adrenergic neuronal progenitors. The low survival rates for high-risk disease point to an urgent need for novel targeted therapeutic approaches. Detailed molecular characterization of the neuroblastoma genomic landscape indicates that ALK-activating mutations are present in 10% of primary tumours.

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Gain of chromosome arm 2p is a previously described entity in neuroblastoma (NB). This genomic address is home to two important oncogenes in NB-MYCN and anaplastic lymphoma kinase (ALK). MYCN amplification is a critical prognostic factor coupled with poor prognosis in NB.

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Oncogenic receptor tyrosine kinases including anaplastic lymphoma kinase (ALK) are implicated in numerous solid and hematologic cancers. ALK mutations are reported in an estimated 9% of neuroblastoma and recent reports indicate that the percentage of ALK-positive cases increases in the relapsed patient population. Initial clinical trial results have shown that it is difficult to inhibit growth of ALK positive neuroblastoma with crizotinib, motivating investigation of next generation ALK inhibitors with higher affinity for ALK.

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Over the last decade, anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase (RTK), has been identified as a fusion partner in a diverse variety of translocation events resulting in oncogenic signaling in many different cancer types. In tumors where the full-length ALK RTK itself is mutated, such as neuroblastoma, the picture regarding the role of ALK as an oncogenic driver is less clear. Neuroblastoma is a complex and heterogeneous tumor that arises from the neural crest derived peripheral nervous system.

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Anaplastic lymphoma kinase (ALK) is a tyrosine kinase receptor that is a clinical target of major interest in cancer. Mutations and rearrangements in trigger the activation of the encoded receptor and its downstream signaling pathways. mutations have been identified in both familial and sporadic neuroblastoma cases as well as in 30 to 40% of relapses, which makes ALK a bona fide target in neuroblastoma therapy.

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Tumors with anaplastic lymphoma kinase (ALK) fusion rearrangements, including non-small-cell lung cancer and anaplastic large cell lymphoma, are highly sensitive to ALK tyrosine kinase inhibitors (TKIs), underscoring the notion that such cancers are addicted to ALK activity. Although mutations in ALK are heavily implicated in childhood neuroblastoma, response to the ALK TKI crizotinib has been disappointing. Embryonal tumors in patients with DNA repair defects such as Fanconi anemia (FA) often have a poor prognosis, because of lack of therapeutic options.

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Activation of the RAS-RAF-MEK-ERK signaling pathway is implicated in driving the initiation and progression of multiple cancers. Several inhibitors targeting the RAS-MAPK pathway are clinically approved as single- or polyagent therapies for patients with specific types of cancer. One example is the MEK inhibitor trametinib, which is included as a rational polytherapy strategy for treating EML4-ALK-positive, EGFR-activated, or KRAS-mutant lung cancers and neuroblastomas that also contain activating mutations in the RAS-MAPK pathway.

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Aberrant activation of anaplastic lymphoma kinase (ALK) has been described in a range of human cancers, including non-small cell lung cancer and neuroblastoma (Hallberg and Palmer, 2013). Vertebrate ALK has been considered to be an orphan receptor and the identity of the ALK ligand(s) is a critical issue. Here we show that FAM150A and FAM150B are potent ligands for human ALK that bind to the extracellular domain of ALK and in addition to activation of wild-type ALK are able to drive 'superactivation' of activated ALK mutants from neuroblastoma.

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Anaplastic lymphoma kinase (ALK) is an important molecular target in neuroblastoma. Although tyrosine kinase inhibitors abrogating ALK activity are currently in clinical use for the treatment of ALK-positive (ALK(+)) disease, monotherapy with ALK tyrosine kinase inhibitors may not be an adequate solution for ALK(+) neuroblastoma patients. Increased expression of the gene encoding the transcription factor MYCN is common in neuroblastomas and correlates with poor prognosis.

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Activation of the anaplastic lymphoma kinase (ALK) receptor tyrosine kinase is a key oncogenic mechanism in a growing number of tumor types. In the majority of cases, ALK is activated by fusion with a dimerizing partner protein as a result of chromosomal translocation events, most studied in the case of the nucleophosmin-ALK and echinoderm microtubule-associated protein-like 4-ALK oncoproteins. It is now also appreciated that the full-length ALK receptor can be activated by point mutations and by deletions within the extracellular domain, such as those observed in neuroblastoma.

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