Publications by authors named "GM Marshall"

Background: The child cancer, neuroblastoma (NB), is characterised by a low incidence of mutations and strong oncogenic embryonal driver signals. Many new targeted epigenetic modifier drugs have failed in human trials as monotherapy.

Methods: We performed a high-throughput, combination chromatin-modifier drug screen against NB cells.

View Article and Find Full Text PDF
Article Synopsis
  • - MYCN amplification is linked to poor outcomes in childhood neuroblastoma and the study investigates the signaling dependencies associated with it through genetic manipulation in mice.
  • - A mutation in the RNF121 gene was found to result in decreased tumor formation, with RNF121 playing a crucial role in enhancing MYCN protein stability and contributing to tumor growth.
  • - Elevated RNF121 levels correlate with poor prognosis in neuroblastoma and laryngeal cancer, suggesting it as a potential target for new cancer therapies.
View Article and Find Full Text PDF

Introduction: Autonomic dysreflexia (AD) is a potentially life-threatening syndrome that can occur in patients with traumatic injury to the spinal cord; however, it has not been well described in patients with non-traumatic spinal cord injury (SCI) from cancer and its treatments.

Case Presentation: We report four cases of autonomic dysreflexia secondary to primary spinal cord tumors and metastatic disease to the spine, and as sequela to cancer treatment. The clinical characteristics, diagnostic considerations, and therapeutic strategies used to mitigate the symptoms are discussed.

View Article and Find Full Text PDF

Children with Down syndrome (DS) are at increased risk of developing haematological malignancies, in particular acute megakaryoblastic leukaemia and acute lymphoblastic leukaemia. The microenvironment established by abnormal haematopoiesis driven by trisomy 21 is compounded by additional genetic and epigenetic changes that can drive leukaemogenesis in patients with DS. GATA-binding protein 1 () somatic mutations are implicated in the development of transient abnormal myelopoiesis and the progression to myeloid leukaemia of DS (ML-DS) and provide a model of the multi-step process of leukaemogenesis in DS.

View Article and Find Full Text PDF
Article Synopsis
  • MYCN oncogene amplification is linked to aggressive childhood neuroblastoma, but a study found a germline mutation in Runx1t1 that can prevent tumor development associated with MYCN.
  • This mutation affects a conserved zinc finger domain and reduces the risk of neuroblastoma by inhibiting cell growth and reversing hyperplasia, which is a precursor to tumor formation.
  • RUNX1T1 is part of a transcriptional repression complex that impacts chromatin accessibility without directly regulating MYCN, and its silencing affects other cancers, indicating its broader significance in tumor biology.
View Article and Find Full Text PDF
Article Synopsis
  • Recent research indicates that precision medicine is effective in developing new treatment options for childhood cancers, specifically for high-risk patients with a low expected cure rate.
  • In a study involving 384 patients, 67% received recommendations for precision-guided treatment (PGT), leading to a 36% objective response rate and better 2-year progression-free survival compared to standard treatments.
  • The most significant benefits from PGT were observed in cases targeting specific genetic markers and when treatment started before disease progression.
View Article and Find Full Text PDF
Article Synopsis
  • * A case of a patient with ETV6-MECOM fusion-positive refractory AML used molecular analysis and drug screening to discover a novel combination therapy involving Ruxolitinib and hydroxyurea, which improved disease control and quality of life.
  • * This case highlights the effectiveness of high throughput drug screening in guiding treatment decisions for high-risk leukaemia patients and the potential benefit of JAK1/2 inhibitors in palliative care.
View Article and Find Full Text PDF

The overall prognosis of acute myeloid leukemia (AML) remains dismal, largely because of the inability of current therapies to kill leukemia stem cells (LSCs) with intrinsic resistance. Loss of the stress sensor growth arrest and DNA damage-inducible 45 alpha (GADD45A) is implicated in poor clinical outcomes, but its role in LSCs and AML pathogenesis is unknown. Here, we define GADD45A as a key downstream target of G protein-coupled receptor (LGR)4 pathway and discover a regulatory role for GADD45A loss in promoting leukemia-initiating activity and oxidative resistance in LGR4/HOXA9-dependent AML, a poor prognosis subset of leukemia.

View Article and Find Full Text PDF

Many of the pro-tumorigenic functions of the oncogene MYCN are attributed to its regulation of global gene expression programs. Alternative splicing is another important regulator of gene expression and has been implicated in neuroblastoma development, however, the molecular mechanisms remain unknown. We found that MYCN up-regulated the expression of the core spliceosomal protein, SNRPD3, in models of neuroblastoma initiation and progression.

View Article and Find Full Text PDF

amplification occurs in approximately 20-30% of neuroblastoma patients and correlates with poor prognosis. The transgenic mouse model mimics the development of human high-risk neuroblastoma and provides strong evidence for the oncogenic function of MYCN. In this study, we identified mitotic dysregulation as a hallmark of tumor initiation in the pre-cancerous ganglia from mice that persists through tumor progression.

View Article and Find Full Text PDF

Background: Paediatric precision oncology aims to match therapeutic agents to driver gene targets. We investigated whether parents and patients regret participation in precision medicine trials, particularly when their hopes are unfulfilled.

Methods: Parents and adolescent patients completed questionnaires at trial enrolment (T0) and after receiving results (T1).

View Article and Find Full Text PDF
Article Synopsis
  • * A study tested 125 patient samples against 126 anticancer drugs, finding strong correlations between specific genomic alterations and effective drug responses, indicating potential targeted treatments.
  • * The integration of high-throughput screening (HTS) with molecular profiling can enhance precision medicine by identifying effective biomarkers and drug combinations for high-risk pediatric cancer patients.
View Article and Find Full Text PDF

Precision medicine programs aim to utilize novel technologies to identify personalized treatments for children with cancer. Delivering these programs requires interdisciplinary efforts, yet the many groups involved are understudied. This study explored the experiences of a broad range of professionals delivering Australia's first precision medicine trial for children with poor-prognosis cancer: the PRecISion Medicine for Children with Cancer (PRISM) national clinical trial of the Zero Childhood Cancer Program.

View Article and Find Full Text PDF

Background: Germline genome sequencing in childhood cancer precision medicine trials may reveal pathogenic or likely pathogenic variants in cancer predisposition genes in more than 10% of children. These findings can have implications for diagnosis, treatment, and the child's and family's future cancer risk. Understanding parents' perspectives of germline genome sequencing is critical to successful clinical implementation.

View Article and Find Full Text PDF

Background: Precision medicine is projected to become integral to childhood cancer care. As such, it is essential to support families to understand what precision medicine entails.

Methods: A total of 182 parents and 23 adolescent patients participating in Precision Medicine for Children with Cancer (PRISM), an Australian precision medicine clinical trial for high-risk childhood cancer, completed questionnaires after study enrollment (time 0 [T0]).

View Article and Find Full Text PDF

The MYCN oncogene and histone deacetylases (HDACs) are key driver genes in the childhood cancer, neuroblastoma. We recently described a novel pyridobenzimidazole analogue, SE486-11, which enhanced the therapeutic effectiveness of HDAC inhibitors by increasing MYCN ubiquitination through effects on the deubiquitinase, ubiquitin-specific protease 5 (USP5). Here we describe the synthesis of a novel series of pyrimido[1,2-a]benzimidazole derivatives, and an evaluation of their cytopathic effects against non-malignant and human neuroblastoma cell lines.

View Article and Find Full Text PDF

Background: Molecular profiling of the tumour immune microenvironment (TIME) has enabled the rational choice of immunotherapies in some adult cancers. In contrast, the TIME of paediatric cancers is relatively unexplored. We speculated that a more refined appreciation of the TIME in childhood cancers, rather than a reliance on commonly used biomarkers such as tumour mutation burden (TMB), neoantigen load and PD-L1 expression, is an essential prerequisite for improved immunotherapies in childhood solid cancers.

View Article and Find Full Text PDF

MYCN is a major oncogenic driver for neuroblastoma tumorigenesis, yet there are no direct MYCN inhibitors. We have previously identified PA2G4 as a direct protein-binding partner of MYCN and drive neuroblastoma tumorigenesis. A small molecule known to bind PA2G4, WS6, significantly decreased tumorigenicity in neuroblastoma mice, along with the inhibition of PA2G4 and MYCN interactions.

View Article and Find Full Text PDF

The mitochondrion is a gatekeeper of apoptotic processes, and mediates drug resistance to several chemotherapy agents used to treat cancer. Neuroblastoma is a common solid cancer in young children with poor clinical outcomes following conventional chemotherapy. We sought druggable mitochondrial protein targets in neuroblastoma cells.

View Article and Find Full Text PDF

Peripheral neuroblastic tumors (PNTs) represent a spectrum of neural-crest-derived tumors, including neuroblastoma, ganglioneuroblastoma, and ganglioneuroma. Malignant cells in PNTs are theorized to interconvert between adrenergic/noradrenergic and mesenchymal/neural crest cell states. Here, single-cell RNA-sequencing analysis of 10 PNTs demonstrates extensive transcriptomic heterogeneity.

View Article and Find Full Text PDF

Background: Pediatric acute lymphoblastic leukemia (ALL) therapy is accompanied by treatment-related toxicities (TRTs) and impaired quality of life. In Australia and New Zealand, children with ALL are treated with either Children's Oncology Group (COG) or international Berlin-Frankfurt-Munster (iBFM) Study Group-based therapy. We conducted a prospective registry study to document symptomatic TRTs (venous thrombosis, neurotoxicity, pancreatitis and bone toxicity), compare TRT outcomes to retrospective TRT data, and measure the impact of TRTs on children's general and cancer-related health-related quality of life (HRQoL) and parents' emotional well-being.

View Article and Find Full Text PDF

Objective: For over two years, the global COVID-19 pandemic has forced major transformations on health, social, and educational systems, with concomitant impacts on mental health. This study aimed to understand the unique and additional challenges faced by children with chronic illness and their families during the COVID-19 era.

Method: Parents of children receiving treatment for a chronic illness within the neurology, cancer, renal and respiratory clinics of Sydney Children's Hospital were invited to participate.

View Article and Find Full Text PDF

Current literature/guidelines regarding the most appropriate term to communicate a cancer-related disease-causing germline variant in childhood cancer lack consensus. Guidelines also rarely address preferences of patients/families. We aimed to assess preferences of parents of children with cancer, genetics professionals, and pediatric oncologists towards terminology to describe a disease-causing germline variant in childhood cancer.

View Article and Find Full Text PDF

Neuroblastoma is a deadly childhood cancer arising in the developing sympathetic nervous system. High-risk patients are currently treated with intensive chemotherapy, which is curative in only 50% of children and leaves some surviving patients with life-long side effects. microRNAs (miRNAs) are critical regulators of neural crest development and are deregulated during neuroblastoma tumorigenesis, making miRNA-based drugs an attractive therapeutic avenue.

View Article and Find Full Text PDF