Whole genome, transcriptome and methylome profiling enhances actionable target discovery in high-risk pediatric cancer

A review on trends in development and translation of omics signatures in cancer

The field of cancer genomics and transcriptomics has evolved from targeted profiling to swift sequencing of individual tumor genome and transcriptome. The steady growth in genome, epigenome, and transcriptome datasets on a genome-wide scale has significantly increased our capability in capturing signatures that represent both the intrinsic and extrinsic biological features of tumors. These biological differences can help in precise molecular subtyping of cancer, predicting tumor progression, metastatic potential, and resistance to therapeutic agents. In this review, we summarized the current development of genomic, methylomic, transcriptomic, proteomic and metabolic signatures in the field of cancer research and highlighted their potentials in clinical applications to improve diagnosis, prognosis, and treatment decision in cancer patients.

Precision cancer medicine platform trials: Concepts and design of AcSé-ESMART

Precision cancer medicine brought the promise of improving outcomes for patients with cancer. High-throughput molecular profiling of tumors at treatment failure aims to direct a patient to a treatment matched to the tumor profile. In this way, improved outcome has been achieved in a small number of patients whose tumors exhibit unique targetable oncogenic drivers. Most cancers, however, contain multiple genetic alterations belonging to and of various hallmarks of cancer; for most of these alterations, there is limited knowledge on the level of evidence, their hierarchical roles in oncogenicity, and utility as biomarkers for response to targeted treatment(s). We developed a proof-of-concept trial that explores new treatment strategies in a molecularly-enriched tumor-agnostic, pediatric population. The evaluation of novel agents, including first-in-child molecules, alone or in combination, is guided by the available understanding of or hypotheses for the mechanisms of action of the diverse cancer events. Main objectives are: to determine 1) recommended phase 2 doses, 2) activity signals to provide the basis for disease specific development, and 3) to define new predictive biomarkers. Here we outline concepts, rationales and designs applied in the European AcSé-ESMART trial and highlight the feasibility but also complexity and challenges of such innovative platform trials.

St. Jude Survivorship Portal: Sharing and Analyzing Large Clinical and Genomic Datasets from Pediatric Cancer Survivors

Childhood cancer survivorship studies generate comprehensive datasets comprising demographic, diagnosis, treatment, outcome, and genomic data from survivors. To broadly share this data, we created the St. Jude Survivorship Portal (https://survivorship.stjude.cloud), the first data portal for sharing, analyzing, and visualizing pediatric cancer survivorship data. More than 1,600 phenotypic variables and 400 million genetic variants from more than 7,700 childhood cancer survivors can be explored on this free, open-access portal. Summary statistics of variables are computed on-the-fly and visualized through interactive and customizable charts. Survivor cohorts can be customized and/or divided into groups for comparative analysis. Users can also seamlessly perform cumulative incidence and regression analyses on the stored survivorship data. Using the portal, we explored the ototoxic effects of platinum-based chemotherapy, uncovered a novel association between mental health, age, and limb amputation, and discovered a novel haplotype in MAGI3 strongly associated with cardiomyopathy specifically in survivors of African ancestry. Significance: The St. Jude Survivorship Portal is the first data portal designed to share and explore clinical and genetic data from childhood cancer survivors. The portal provides both open- and controlled-access features and will fulfill a wide range of data sharing needs of the survivorship research community and beyond. See co-corresponding author Xin Zhou discuss this research article, published simultaneously at the AACR Annual Meeting 2024: https://vimeo.com/932617204/7d99fa4958.

Opportunities for Improving Detection of Cancer Predisposition Syndromes in Pediatric Solid Tumor Patients

BACKGROUND

Detection of cancer predisposition syndromes (CPS) depends on identifying risk factors, including tumor type, family history, and physical findings, to prompt referral for genetic counseling/testing. Whether pediatric oncology providers (POPs) collect adequate family history information is unknown.

METHODS

A single-institution retrospective chart review of solid tumor patients <18 years of age referred for a CPS evaluation between January 1, 2017 and January 31, 2019 was performed. POP adherence to American Society of Clinical Oncology (ASCO) family history collection recommendations was measured and compared with genetic counselor performance. Whether sufficient family history was documented to satisfy the criteria of three genetic counseling referral guidelines [American College of Medical Genetics (ACMG), updated Jongmans (UJ), and McGill Interactive Pediatric OncoGenetic Guidelines (MIPOGG)] was evaluated.

RESULTS

POPs and genetic counselors achieved all 6 ASCO family history metrics in 3% and 99% of 129 eligible cases, respectively. POPs failed to document sufficient family history to satisfy genetic counseling referral criteria in most cases (74% ACMG, 73% UJ, 79% MIPOGG).

CONCLUSIONS

POPs perform poorly in family history collection, raising concern that some patients at risk for a CPS based on their family history may not be referred for genetic counseling/testing. Interventions to improve family history collection are needed to enhance CPS detection.

Identification of TP53 germline variants in pediatric patients undergoing tumor testing: strategy and prevalence

BACKGROUND

TP53 alterations are common in certain pediatric cancers, making identification of putative germline variants through tumor genomic profiling crucial for disease management.

METHODS

We analyzed TP53 alterations in 3123 tumors from 2788 pediatric patients sequenced using tumor-only or tumor-normal paired panels. Germline confirmatory testing was performed when indicated. Somatic and germline variants were classified based on published guidelines.

RESULTS

In 248 tumors from 222 patients, 284 tier 1/2 TP53 sequence and small copy number variants were detected. Following germline classification, 86.6% of 142 unique variants were pathogenic or likely pathogenic. Confirmatory testing on 118 patients revealed germline TP53 variants in 28 of them (23 pathogenic or likely pathogenic and 5 of uncertain significance), suggesting a minimum Li-Fraumeni syndrome incidence of 0.8% (23/2788) in this cohort, 10.4% (23/222) in patients with TP53 variant-carrying tumors, and 19.5% (23/118) with available normal samples. About 25% (7/28) of patients with germline TP53 variants did not meet Li-Fraumeni syndrome diagnostic or testing criteria, while 20.9% (28/134) with confirmed or inferred somatic origins did. TP53 biallelic inactivation occurred in 75% of germline carrier tumors and was also prevalent in other groups, causing an elevated tumor-observed variant allelic fraction. Somatic evidence, however, including low variant allele fraction correctly identified only 27.8% (25/90) of patients with confirmed somatic TP53 variants.

CONCLUSION

The high incidence and variable phenotype of Li-Fraumeni syndrome in this cohort highlights the importance of assessing germline status of TP53 variants identified in all pediatric tumors. Without clear somatic evidence, distinguishing somatic from germline origins is challenging. Classifying germline and somatic variants should follow appropriate guidelines.

Economic Impact of Whole Genome Sequencing and Whole Transcriptome Sequencing Versus Routine Diagnostic Molecular Testing to Stratify Patients with B-Cell Acute Lymphoblastic Leukemia

Whole genome and whole transcriptome sequencing (WGTS) can accurately distinguish B-cell acute lymphoblastic leukemia (B-ALL) genomic subtypes. However, whether this is economically viable remains unclear. This study compared the direct costs and molecular subtype classification yield using different testing strategies for WGTS in adolescent and young adult/adult patients with B-ALL. These approaches were: (1) combined BCR::ABL1 by fluorescence in situ hybridization (FISH) + WGTS for all patients; and (2) sequential BCR::ABL1 FISH + WGTS contingent on initial BCR::ABL1 FISH test outcome. The cost of routine diagnostic testing was estimated using Medicare or hospital fees, and the additional cost of WGTS was evaluated from the health care provider perspective using time-driven activity-based costing with resource identification elicited from experts. Molecular subtype classification yield data were derived from literature sources. Parameter uncertainty was assessed through deterministic sensitivity analysis; additional scenario analyses were performed. The total per patient cost of WGTS was $4319 (all costs reported in US dollars); consumables accounted for 74% of the overall cost, primarily driven by sequencing-related consumables. The incremental cost per additional patient categorized into molecular subtype was $8498 for combined BCR::ABL1 FISH + WGTS for all patients and $5656 for initial BCR::ABL1 FISH + WGTS for select patients compared with routine diagnostic testing. A reduction in the consumable costs of WGTS or an increase in the yield of molecular subtype classification is favorable.

Evolution of the Innovative Therapies for Children With Cancer Consortium Trial Portfolio for Drug Development for Children With Cancer

PURPOSE

The aim of the Innovative Therapies for Children with Cancer (ITCC) consortium is to improve access to novel therapies for children and adolescents with cancer. The evolution of the ITCC clinical trial portfolio since 2003 was reviewed.

METHODS

All ITCC-labeled phase I/II trials opened between January 1, 2003 and February 3, 2018 were analyzed in two periods (2003-2010 and 2011-2018), and data were extracted from the ITCC database, regulatory agencies' registries, and publications.

RESULTS

Sixty-one trials (62% industry-sponsored) enrolled 3,198 patients. The number of trials in the second period increased by almost 300% (16 v 45). All biomarker-driven trials (n = 14) were conducted in the second period. The use of rolling six and model-based designs increased (1 of 9, 11% v 21 of 31, 68%), and that of 3 + 3 designs decreased (5 of 9, 55% v 5 of 31, 16%; P = .014). The proportion of studies evaluating chemotherapeutics only decreased (5 of 16, 31% v 4 of 45, 9%), the proportion of single-agent targeted therapies did not change (9 of 16, 56.2% v 24 of 45, 53.3%), the proportion of combination targeted therapies trials increased (2 of 16, 12%, v 17 of 45, 38%), the proportion of randomized phase II trials increased (1 of 7, 14% v 8 of 14, 57%). More trials were part of a pediatric investigation plan in the second period (4 of 16, 25% v 21 of 45, 46%). The median time for Ethics Committees' approvals was 1.7 times longer for academic compared with industry-sponsored trials.

CONCLUSION

This study reports a shift in the paradigm of early drug development for childhood cancers, with more biologically relevant targets evaluated in biomarker-driven trials or in combination with other therapies and with more model-based or randomized designs and a greater focus on fulfilling regulatory requirements. Improvement of trial setup and recruitment could increase the number of patients benefiting from novel agents.

Molecular profiling of 888 pediatric tumors informs future precision trials and data-sharing initiatives in pediatric cancer

To inform clinical trial design and real-world precision pediatric oncology practice, we classified diagnoses, assessed the landscape of mutations, and identified genomic variants matching trials in a large unselected institutional cohort of solid tumors patients sequenced at Dana-Farber / Boston Children's Cancer and Blood Disorders Center. Tumors were sequenced with OncoPanel, a targeted next-generation DNA sequencing panel. Diagnoses were classified according to the International Classification of Diseases for Oncology (ICD-O-3.2). Over 6.5 years, 888 pediatric cancer patients with 95 distinct diagnoses had successful tumor sequencing. Overall, 33% (n = 289/888) of patients had at least 1 variant matching a precision oncology trial protocol, and 14% (41/289) were treated with molecularly targeted therapy. This study highlights opportunities to use genomic data from hospital-based sequencing performed either for research or clinical care to inform ongoing and future precision oncology clinical trials. Furthermore, the study results emphasize the importance of data sharing to define the genomic landscape and targeted treatment opportunities for the large group of rare pediatric cancers we encounter in clinical practice.

Precision-guided treatment in high-risk pediatric cancers

Recent research showed that precision medicine can identify new treatment strategies for patients with childhood cancers. However, it is unclear which patients will benefit most from precision-guided treatment (PGT). Here we report consecutive data from 384 patients with high-risk pediatric cancer (with an expected cure rate of less than 30%) who had at least 18 months of follow-up on the ZERO Childhood Cancer Precision Medicine Program PRecISion Medicine for Children with Cancer (PRISM) trial. A total of 256 (67%) patients received PGT recommendations and 110 (29%) received a recommended treatment. PGT resulted in a 36% objective response rate and improved 2-year progression-free survival compared with standard of care (26% versus 12%; P = 0.049) or targeted agents not guided by molecular findings (26% versus 5.2%; P = 0.003). PGT based on tier 1 evidence, PGT targeting fusions or commenced before disease progression had the greatest clinical benefit. Our data show that PGT informed by comprehensive molecular profiling significantly improves outcomes for children with high-risk cancers. ClinicalTrials.gov registration: NCT03336931.

Recent Advancements and Innovations in Pediatric Precision Oncology

Precision oncology incorporates comprehensive genomic profiling into the individualized clinical care of pediatric cancer patients. In recent years, comprehensive pan-cancer analyses have led to the successful implementation of genomics-based pediatric trials and accelerated approval of novel targeted agents. In addition, disease-specific studies have resulted in molecular subclassification of myriad cancer types with subsequent tailoring of treatment intensity based on the patient's prognostic factors. This review discusses the progress of the field and highlights developments that are leading to more personalized cancer care and improved patient outcomes. Increased understanding of the evolution of precision oncology over recent decades emphasizes the tremendous impact of improved genomic applications. New technologies and improved diagnostic modalities offer further promise for future advancements within the field.

Oncogenic and immunological targets for matched therapy of pediatric blood cancer patients: Dutch iTHER study experience

Over the past 10 years, institutional and national molecular tumor boards have been implemented for relapsed or refractory pediatric cancer to prioritize targeted drugs for individualized treatment based on actionable oncogenic lesions, including the Dutch iTHER platform. Hematological malignancies form a minority in precision medicine studies. Here, we report on 56 iTHER leukemia/lymphoma patients for which we considered cell surface markers and oncogenic aberrations as actionable events, supplemented with ex vivo drug sensitivity for six patients. Prior to iTHER registration, 34% of the patients had received allogeneic hematopoietic cell transplantation (HCT) and 18% CAR-T therapy. For 51 patients (91%), a sample with sufficient tumor percentage (≥20%) required for comprehensive diagnostic testing was obtained. Up to 10 oncogenic actionable events were prioritized in 49/51 patients, and immunotherapy targets were identified in all profiled patients. Targeted treatment(s) based on the iTHER advice was given to 24 of 51 patients (47%), including immunotherapy in 17 patients, a targeted drug matching an oncogenic aberration in 12 patients, and a drug based on ex vivo drug sensitivity in one patient, resulting in objective responses and a bridge to HCT in the majority of the patients. In conclusion, comprehensive profiling of relapsed/refractory hematological malignancies showed multiple oncogenic and immunotherapy targets for a precision medicine approach, which requires multidisciplinary expertise to prioritize the best treatment options for this rare, heavily pretreated pediatric population.

Benefits for children with suspected cancer from routine whole-genome sequencing

Clinical whole-genome sequencing (WGS) has been shown to deliver potential benefits to children with cancer and to alter treatment in high-risk patient groups. It remains unknown whether offering WGS to every child with suspected cancer can change patient management. We collected WGS variant calls and clinical and diagnostic information from 281 children (282 tumors) across two English units (n = 152 from a hematology center, n = 130 from a solid tumor center) where WGS had become a routine test. Our key finding was that variants uniquely attributable to WGS changed the management in ~7% (20 out of 282) of cases while providing additional disease-relevant findings, beyond standard-of-care molecular tests, in 108 instances for 83 (29%) cases. Furthermore, WGS faithfully reproduced every standard-of-care molecular test (n = 738) and revealed several previously unknown genomic features of childhood tumors. We show that WGS can be delivered as part of routine clinical care to children with suspected cancer and can change clinical management by delivering unexpected genomic insights. Our experience portrays WGS as a clinically impactful assay for routine practice, providing opportunities for assay consolidation and for delivery of molecularly informed patient care.

Parents' and patients' perspectives, experiences, and preferences for germline genetic or genomic testing of children with cancer: A systematic review

PURPOSE

Germline testing in pediatric cancer presents opportunities and challenges. Understanding family perspectives, experiences, and preferences will optimize integration into routine care.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched 4 databases for studies exploring perspectives, experiences, and preferences of parents/caregivers and/or patients regarding germline testing of children with cancer. Qualitative and quantitative data were extracted, organized, and summarized by research question and themes.

RESULTS

We identified 2286 unique articles, of which 24 were included. Interest in and uptake of testing was high. Families were motivated by altruism and a desire for inheritance/causation information. Testing barriers included psychological concerns, timing of the testing approach if offered at diagnosis or in a high-risk cancer setting and privacy/discrimination. Testing experiences highlighted challenges yet also positive impacts, with results providing psychological relief and informing proactive decision making. Timing preferences varied; however, allowing time to adjust to a new diagnosis was a common theme. Most wanted to receive as many germline sequencing-related results as possible.

CONCLUSION

Findings underscore the importance of integrating germline analyses into pediatric cancer care with flexibility and support for families facing challenges. Where possible, consent should be provided at a time that suits each family's situation with access to information aligning with their needs and preferences.

PROSPERO

CRD42023444890.

Skeletal overgrowth in a pre-pubescent child treated with pan-FGFR inhibitor

Fibroblast growth factors and their receptors (FGFR) have major roles in both human growth and oncogenesis. In adults, therapeutic FGFR inhibitors have been successful against tumors that carry somatic FGFR mutations. In pediatric patients, trials testing these anti-tumor FGFR inhibitor therapeutics are underway, with several recent reports suggesting modest positive responses. Herein, we report an unforeseen outcome in a pre-pubescent child with an FGFR1-mutated glioma who was successfully treated with FDA-approved erdafitinib, a pan-FGFR inhibitor approved for treatment of Bladder tumors. While on treatment with erdafitinib, the patient experienced rapid skeletal and long bone overgrowth resulting in kyphoscoliosis, reminiscent of patients with congenital loss-of-function FGFR3 mutations. We utilized normal dermal fibroblast cells established from the patient as a surrogate model to demonstrate that insulin-like growth factor 1 (IGF-1), a factor important for developmental growth of bones and tissues, can activate the PI3K/AKT pathway in erdafitinib-treated cells but not the MAPK/ERK pathway. The IGF-I-activated PI3K/AKT signaling rescued normal fibroblasts from the cytotoxic effects of erdafitinib by promoting cell survival. We, therefore, postulate that IGF-I-activated P13K/AKT signaling likely continues to promote bone elongation in the growing child, but not in adults, treated with therapeutic pan-FGFR inhibitors. Importantly, since activated MAPK signaling counters bone elongation, we further postulate that prolonged blockage of the MAPK pathway with pan-FGFR inhibitors, together with actions of growth-promoting factors including IGF-1, could explain the abnormal skeletal and axial growth suffered by our pre-pubertal patient during systemic therapeutic use of pan-FGFR inhibitors. Further studies to find more targeted, and/or appropriate dosing, of pan-FGFR inhibitor therapeutics for children are essential to avoid unexpected off-target effects as was observed in our young patient.

Update on Cancer Predisposition Syndromes and Surveillance Guidelines for Childhood Brain Tumors

Tumors of the central nervous system (CNS) comprise the second most common group of neoplasms in childhood. The incidence of germline predisposition among children with brain tumors continues to grow as our knowledge on disease etiology increases. Some children with brain tumors may present with nonmalignant phenotypic features of specific syndromes (e.g., nevoid basal cell carcinoma syndrome, neurofibromatosis type 1 and type 2, DICER1 syndrome, and constitutional mismatch-repair deficiency), while others may present with a strong family history of cancer (e.g., Li-Fraumeni syndrome) or with a rare tumor commonly found in the context of germline predisposition (e.g., rhabdoid tumor predisposition syndrome). Approximately 50% of patients with a brain tumor may be the first in a family identified to have a predisposition. The past decade has witnessed a rapid expansion in our molecular understanding of CNS tumors. A significant proportion of CNS tumors are now well characterized and known to harbor specific genetic changes that can be found in the germline. Additional novel predisposition syndromes are also being described. Identification of these germline syndromes in individual patients has not only enabled cascade testing of family members and early tumor surveillance but also increasingly affected cancer management in those patients. Therefore, the AACR Cancer Predisposition Working Group chose to highlight these advances in CNS tumor predisposition and summarize and/or generate surveillance recommendations for established and more recently emerging pediatric brain tumor predisposition syndromes.

circRNAs as prognostic markers in pediatric acute myeloid leukemia

Circular RNAs (circRNAs) arise from precursor mRNA processing through back-splicing and have been increasingly recognized for their functions in various cancers including acute myeloid leukemia (AML). However, the prognostic implications of circRNA in AML remain unclear. We conducted a comprehensive genome-wide analysis of circRNAs using RNA-seq data in pediatric AML. We revealed a group of circRNAs associated with inferior outcomes, exerting effects on cancer-related pathways. Several of these circRNAs were transcribed directly from genes with established functions in AML, such as circRUNX1, circWHSC1, and circFLT3. Further investigations indicated the increased number of circRNAs and linear RNAs splicing were significantly correlated with inferior clinical outcomes, highlighting the pivotal role of splicing dysregulation. Subsequent analysis identified a group of upregulated RNA binding proteins in AMLs associated with high number of circRNAs, with TROVE2 being a prominent candidate, suggesting their involvement in circRNA associated prognosis. Through the integration of drug sensitivity data, we pinpointed 25 drugs that could target high-risk AMLs characterized by aberrant circRNA transcription. These findings underscore prognostic significance of circRNAs in pediatric AML and offer an alternative perspective for treating high-risk cases in this malignancy.

Promise and Perils of Precision Oncology for Patients With Pediatric and Young Adult Sarcomas

The completion of multiple national pediatric precision oncology platform trials and the incorporation of standardized molecular profiling into the diagnostic care of pediatric and young adult patients with sarcomas have proven the feasibility and potential of the approach. In this work, we explore the current state of the art of precision oncology for pediatric and young adults with sarcoma. We highlight important lessons learned and the challenges that should be addressed in the next generation of trials. The chapter outlines current efforts to improve standardization of molecular assays, harmonization of data collection, and novel molecular tools such as cell-free DNA analyses. Finally, we discuss the impacts and psychosocial outcomes experienced by patients and communication strategies for providers.

Developmental origins shape the paediatric cancer genome

In the past two decades, technological advances have brought unprecedented insights into the paediatric cancer genome revealing characteristics distinct from those of adult cancer. Originating from developing tissues, paediatric cancers generally have low mutation burden and are driven by variants that disrupt the transcriptional activity, chromatin state, non-coding cis-regulatory regions and other biological functions. Within each tumour, there are multiple populations of cells with varying states, and the lineages of some can be tracked to their fetal origins. Genome-wide genetic screening has identified vulnerabilities associated with both the cell of origin and transcription deregulation in paediatric cancer, which have become a valuable resource for designing new therapeutic approaches including those for small molecules, immunotherapy and targeted protein degradation. In this Review, we present recent findings on these facets of paediatric cancer from a pan-cancer perspective and provide an outlook on future investigations.

PERCEPTION predicts patient response and resistance to treatment using single-cell transcriptomics of their tumors

Tailoring optimal treatment for individual cancer patients remains a significant challenge. To address this issue, we developed PERCEPTION (PERsonalized Single-Cell Expression-Based Planning for Treatments In ONcology), a precision oncology computational pipeline. Our approach uses publicly available matched bulk and single-cell (sc) expression profiles from large-scale cell-line drug screens. These profiles help build treatment response models based on patients' sc-tumor transcriptomics. PERCEPTION demonstrates success in predicting responses to targeted therapies in cultured and patient-tumor-derived primary cells, as well as in two clinical trials for multiple myeloma and breast cancer. It also captures the resistance development in patients with lung cancer treated with tyrosine kinase inhibitors. PERCEPTION outperforms published state-of-the-art sc-based and bulk-based predictors in all clinical cohorts. PERCEPTION is accessible at https://github.com/ruppinlab/PERCEPTION . Our work, showcasing patient stratification using sc-expression profiles of their tumors, will encourage the adoption of sc-omics profiling in clinical settings, enhancing precision oncology tools based on sc-omics.

Proteomic insights into paediatric cancer: Unravelling molecular signatures and therapeutic opportunities

Survival rates in some paediatric cancers have improved greatly over recent decades, in part due to the identification of diagnostic, prognostic and predictive molecular signatures, and the development of risk-directed therapies. However, other paediatric cancers have proved difficult to treat, and there is an urgent need to identify novel biomarkers that reveal therapeutic opportunities. The proteome is the total set of expressed proteins present in a cell or tissue at a point in time, and is vastly more dynamic than the genome. Proteomics holds significant promise for cancer research, as proteins are ultimately responsible for cellular phenotype and are the target of most anticancer drugs. Here, we review the discoveries, opportunities and challenges of proteomic analyses in paediatric cancer, with a focus on mass spectrometry (MS)-based approaches. Accelerating incorporation of proteomics into paediatric precision medicine has the potential to improve survival and quality of life for children with cancer.

Keratin-Positive Giant Cell Tumor of Bone and Soft Tissue With HMGA2::NCOR2 Fusion in Children Under 10 With Response to Imatinib Therapy: A Case Series

HMGA2::NCOR2 keratin-positive giant cell tumors in children with response to imatinib in an infant.

Genomic Newborn Screening for Pediatric Cancer Predisposition Syndromes: A Holistic Approach

As next-generation sequencing (NGS) has become more widely used, germline and rare genetic variations responsible for inherited illnesses, including cancer predisposition syndromes (CPSs) that account for up to 10% of childhood malignancies, have been found. The CPSs are a group of germline genetic disorders that have been identified as risk factors for pediatric cancer development. Excluding a few "classic" CPSs, there is no agreement regarding when and how to conduct germline genetic diagnostic studies in children with cancer due to the constant evolution of knowledge in NGS technologies. Various clinical screening tools have been suggested to aid in the identification of individuals who are at greater risk, using diverse strategies and with varied outcomes. We present here an overview of the primary clinical and molecular characteristics of various CPSs and summarize the existing clinical genomics data on the prevalence of CPSs in pediatric cancer patients. Additionally, we discuss several ethical issues, challenges, limitations, cost-effectiveness, and integration of genomic newborn screening for CPSs into a healthcare system. Furthermore, we assess the effectiveness of commonly utilized decision-support tools in identifying patients who may benefit from genetic counseling and/or direct genetic testing. This investigation highlights a tailored and systematic approach utilizing medical newborn screening tools such as the genome sequencing of high-risk newborns for CPSs, which could be a practical and cost-effective strategy in pediatric cancer care.

Whole genome and transcriptome integrated analyses guide clinical care of pediatric poor prognosis cancers

The role for routine whole genome and transcriptome analysis (WGTA) for poor prognosis pediatric cancers remains undetermined. Here, we characterize somatic mutations, structural rearrangements, copy number variants, gene expression, immuno-profiles and germline cancer predisposition variants in children and adolescents with relapsed, refractory or poor prognosis malignancies who underwent somatic WGTA and matched germline sequencing. Seventy-nine participants with a median age at enrollment of 8.8 y (range 6 months to 21.2 y) are included. Germline pathogenic/likely pathogenic variants are identified in 12% of participants, of which 60% were not known prior. Therapeutically actionable variants are identified by targeted gene report and whole genome in 32% and 62% of participants, respectively, and increase to 96% after integrating transcriptome analyses. Thirty-two molecularly informed therapies are pursued in 28 participants with 54% achieving a clinical benefit rate; objective response or stable disease ≥6 months. Integrated WGTA identifies therapeutically actionable variants in almost all tumors and are directly translatable to clinical care of children with poor prognosis cancers.

Adult-Onset Cancer Predisposition Syndromes in Children and Adolescents-To Test or not to Test?

With the increasing use of comprehensive germline genetic testing of children and adolescents with cancer, it has become evident that pathogenic variants (PV) in adult-onset cancer predisposition genes (aoCPG) underlying adult-onset cancer predisposition syndromes, such as Lynch syndrome or hereditary breast and ovarian cancer, are enriched and reported in 1% to 2% of children and adolescents with cancer. However, the causal relationship between PVs in aoCPGs and childhood cancer is still under investigation. The best-studied examples include heterozygous PVs in mismatch repair genes associated with Lynch syndrome in children with mismatch repair deficient high-grade glioma, heterozygous PVs in BARD1 in childhood neuroblastoma, and heterozygous PVs in BRCA2 in children with rhabdomyosarcoma. The low penetrance for pediatric cancers is considered to result from a combination of the low baseline risk of cancer in childhood and the report of only a modest relative risk of disease in childhood. Therefore, we do not advise that healthy children empirically be tested for PVs in an aoCPG before adulthood outside a research study. However, germline panel testing is increasingly being performed in children and adolescents with cancer, and exome and genome sequencing may be offered more commonly in this population in the future. The precise pediatric cancer risks and spectra associated with PVs in aoCPGs, underlying cellular mechanisms and somatic mutational signatures, as well as treatment response, second neoplasm risks, and psycho-oncological aspects require further research.

Paradigm shift required for translational research on the brain

Biomedical research on the brain has led to many discoveries and developments, such as understanding human consciousness and the mind and overcoming brain diseases. However, historical biomedical research on the brain has unique characteristics that differ from those of conventional biomedical research. For example, there are different scientific interpretations due to the high complexity of the brain and insufficient intercommunication between researchers of different disciplines owing to the limited conceptual and technical overlap of distinct backgrounds. Therefore, the development of biomedical research on the brain has been slower than that in other areas. Brain biomedical research has recently undergone a paradigm shift, and conducting patient-centered, large-scale brain biomedical research has become possible using emerging high-throughput analysis tools. Neuroimaging, multiomics, and artificial intelligence technology are the main drivers of this new approach, foreshadowing dramatic advances in translational research. In addition, emerging interdisciplinary cooperative studies provide insights into how unresolved questions in biomedicine can be addressed. This review presents the in-depth aspects of conventional biomedical research and discusses the future of biomedical research on the brain.

It provides families with other avenues for treatment when there are no other options Surgeons' perspectives of being part of a precision medicine trial for poor prognosis paediatric cancer patients: A short report

OBJECTIVE

Precision medicine is transforming cancer treatment, yet the perspectives of surgeons who often play a critical role in the delivery of precision medicine remain understudied.

METHODS

We conducted semi-structured interviews with 13 surgeons involved in a precision medicine trial for children with poor prognosis cancer. We explored knowledge of genetics, confidence with somatic and germline results, ratings of benefit to stakeholders and willingness to undertake surgical procedures.

RESULTS

Surgeons generally had positive attitudes towards precision medicine but expressed concerns about families' unrealistic expectations, mixed opinions on the benefits and the use of research-only biopsies. Most surgeons rated their genetics knowledge as 'good' (69%) and felt 'very confident' in identifying genetic specialists (66%), but 'not confident' (66.6%) in making treatment recommendations. Surgeons' willingness to undertake a procedure was influenced by potential patient benefit.

CONCLUSIONS

Our findings support the need for more workforce and training support for surgeons to fully engage with precision medicine.

Poly-pharmacology of existing drugs: How to crack the code?

Drug development in oncology is highly challenging, with less than 5% success rate in clinical trials. This alarming figure points out the need to study in more details the multiple biological effects of drugs in specific contexts. Indeed, the comprehensive assessment of drug poly-pharmacology can provide insights into their therapeutic and adverse effects, to optimize their utilization and maximize the success rate of clinical trials. Recent technological advances have made possible in-depth investigation of drug poly-pharmacology. This review first highlights high-throughput methodologies that have been used to unveil new mechanisms of action of existing drugs. Then, we discuss how emerging chemo-proteomics strategies allow effectively dissecting the poly-pharmacology of drugs in an unsupervised manner.

Precision Oncology in Pediatric Cancer Surgery

Pediatric precision oncology has provided a greater understanding of the wide range of molecular alterations in difficult-to-treat or rare tumors with the aims of increasing survival as well as decreasing toxicity and morbidity from current cytotoxic therapies. In this article, the authors discuss the current state of pediatric precision oncology which has increased access to novel targeted therapies while also providing a framework for clinical implementation in this unique population. The authors evaluate the targetable mutations currently under investigation-with a focus on pediatric solid tumors-and discuss the key surgical implications associated with novel targeted therapies.

High Comorbidity of Pediatric Cancers in Patients with Birth Defects: Insights from Whole Genome Sequencing Analysis of Copy Number Variations

BACKGROUND

Patients with birth defects (BD) exhibit an elevated risk of cancer. We aimed to investigate the potential link between pediatric cancers and BDs, exploring the hypothesis of shared genetic defects contributing to the coexistence of these conditions.

METHODS

This study included 1454 probands with BDs (704 females and 750 males), including 619 (42.3%) with and 845 (57.7%) without co-occurrence of pediatric onset cancers. Whole genome sequencing (WGS) was done at 30X coverage through the Kids First/Gabriella Miller X01 Program.

RESULTS

8211 CNV loci were called from the 1454 unrelated individuals. 191 CNV loci classified as pathogenic/likely pathogenic (P/LP) were identified in 309 (21.3%) patients, with 124 (40.1%) of these patients having pediatric onset cancers. The most common group of CNVs are pathogenic deletions covering the region ChrX:52,863,011-55,652,521, seen in 162 patients including 17 males. Large recurrent P/LP duplications >5MB were detected in 33 patients.

CONCLUSIONS

This study revealed that P/LP CNVs were common in a large cohort of BD patients with high rate of pediatric cancers. We present a comprehensive spectrum of P/LP CNVs in patients with BDs and various cancers. Notably, deletions involving E2F target genes and genes implicated in mitotic spindle assembly and G2/M checkpoint were identified, potentially disrupting cell-cycle progression and providing mechanistic insights into the concurrent occurrence of BDs and cancers.

Diagnostic yield and clinical impact of germline sequencing in children with CNS and extracranial solid tumors-a nationwide, prospective Swedish study

Background

Childhood cancer predisposition (ChiCaP) syndromes are increasingly recognized as contributing factors to childhood cancer development. Yet, due to variable availability of germline testing, many children with ChiCaP might go undetected today. We report results from the nationwide and prospective ChiCaP study that investigated diagnostic yield and clinical impact of integrating germline whole-genome sequencing (gWGS) with tumor sequencing and systematic phenotyping in children with solid tumors.

Methods

gWGS was performed in 309 children at diagnosis of CNS (n = 123, 40%) or extracranial (n = 186, 60%) solid tumors and analyzed for disease-causing variants in 189 known cancer predisposing genes. Tumor sequencing data were available for 74% (227/309) of patients. In addition, a standardized clinical assessment for underlying predisposition was performed in 95% (293/309) of patients.

Findings

The prevalence of ChiCaP diagnoses was 11% (35/309), of which 69% (24/35) were unknown at inclusion (diagnostic yield 8%, 24/298). A second-hit and/or relevant mutational signature was observed in 19/21 (90%) tumors with informative data. ChiCaP diagnoses were more prevalent among patients with retinoblastomas (50%, 6/12) and high-grade astrocytomas (37%, 6/16), and in those with non-cancer related features (23%, 20/88), and ≥2 positive ChiCaP criteria (28%, 22/79). ChiCaP diagnoses were autosomal dominant in 80% (28/35) of patients, yet confirmed de novo in 64% (18/28). The 35 ChiCaP findings resulted in tailored surveillance (86%, 30/35) and treatment recommendations (31%, 11/35).

Interpretation

Overall, our results demonstrate that systematic phenotyping, combined with genomics-based diagnostics of ChiCaP in children with solid tumors is feasible in large-scale clinical practice and critically guides personalized care in a sizable proportion of patients.

Funding

The study was supported by the Swedish Childhood Cancer Fund and the Ministry of Health and Social Affairs.

High throughput screening aids clinical decision-making in refractory acute myeloid leukaemia

BACKGROUND

Despite advances in therapeutics for adverse-risk acute myeloid leukaemia (AML), overall survival remains poor, especially in refractory disease. Comprehensive tumour profiling and pre-clinical drug testing can identify effective personalised therapies.

CASE

We describe a case of ETV6-MECOM fusion-positive refractory AML, where molecular analysis and in vitro high throughput drug screening identified a tolerable, novel targeted therapy and provided rationale for avoiding what could have been a toxic treatment regimen. Ruxolitinib combined with hydroxyurea led to disease control and enhanced quality-of-life in a patient unsuitable for intensified chemotherapy or allogeneic stem cell transplantation.

CONCLUSION

This case report demonstrates the feasibility and role of combination pre-clinical high throughput screening to aid decision making in high-risk leukaemia. It also demonstrates the role a JAK1/2 inhibitor can have in the palliative setting in select patients with AML.

Clinical trial inclusion in patients with relapsed/refractory neuroblastoma following the European Precision Cancer Medicine trial MAPPYACTS

INTRODUCTION

Despite poor survival for patients with relapsed or refractory neuroblastoma, only 10-16% of patients are reported to be included in early phase trials. This study aimed to explore the impact of molecular profiling within the prospective precision cancer medicine trial MAPPYACTS (NCT02613962) on subsequent early phase trial recruitment and treatment by matched targeted therapies in this population.

METHODS AND MATERIALS

Clinical data from all French patients with relapsed/refractory neuroblastoma enrolled in MAPPYACTS were analyzed for subsequent matched/non-matched targeted treatment based on clinical tumor board (CMTB) recommendations.

RESULTS

From 93 patients with neuroblastoma included in French centers, 78 (84%) underwent whole exome and RNA sequencing and were discussed in the CMTB. Higher rate of successful sequencing analysis was observed in patients with relapsed disease compared to those with refractory disease (p = 0.0002). Among the 50 patients that presented with a new disease relapse/progression after the CMTB recommendations, 35 patients (70%) had at least one actionable alteration identified on the tumor at the time of relapse. Eighteen patients (36%) were included in an early phase clinical trial, 11 of these with a matched agent, 7 with a non-matched treatment; 13 patients were included in the AcSé ESMART trial. Five patients (10%) received a matched targeted therapy outside a clinical trial.

CONCLUSION

Patients with neuroblastoma in the European MAPPYACTS trial were more likely to be included in early phase trials compared to previous reports. Early deep sequencing at first treatment failure, comprehensive therapeutic discussions in molecular tumor boards and innovative trials like AcSé -ESMART improve access to innovative therapies for patients with relapsed/refractory neuroblastoma.

CLINICAL TRIAL REGISTRATION

NCT02613962.

Feasibility of functional precision medicine for guiding treatment of relapsed or refractory pediatric cancers

Children with rare, relapsed or refractory cancers often face limited treatment options, and few predictive biomarkers are available that can enable personalized treatment recommendations. The implementation of functional precision medicine (FPM), which combines genomic profiling with drug sensitivity testing (DST) of patient-derived tumor cells, has potential to identify treatment options when standard-of-care is exhausted. The goal of this prospective observational study was to generate FPM data for pediatric patients with relapsed or refractory cancer. The primary objective was to determine the feasibility of returning FPM-based treatment recommendations in real time to the FPM tumor board (FPMTB) within a clinically actionable timeframe (<4 weeks). The secondary objective was to assess clinical outcomes from patients enrolled in the study. Twenty-five patients with relapsed or refractory solid and hematological cancers were enrolled; 21 patients underwent DST and 20 also completed genomic profiling. Median turnaround times for DST and genomics were within 10 days and 27 days, respectively. Treatment recommendations were made for 19 patients (76%), of whom 14 received therapeutic interventions. Six patients received subsequent FPM-guided treatments. Among these patients, five (83%) experienced a greater than 1.3-fold improvement in progression-free survival associated with their FPM-guided therapy relative to their previous therapy, and demonstrated a significant increase in progression-free survival and objective response rate compared to those of eight non-guided patients. The findings from our proof-of-principle study illustrate the potential for FPM to positively impact clinical care for pediatric and adolescent patients with relapsed or refractory cancers and warrant further validation in large prospective studies. ClinicalTrials.gov registration: NCT03860376 .

Refining risk prediction in pediatric acute lymphoblastic leukemia through DNA methylation profiling

Acute lymphoblastic leukemia (ALL) is the most prevalent cancer in children, and despite considerable progress in treatment outcomes, relapses still pose significant risks of mortality and long-term complications. To address this challenge, we employed a supervised machine learning technique, specifically random survival forests, to predict the risk of relapse and mortality using array-based DNA methylation data from a cohort of 763 pediatric ALL patients treated in Nordic countries. The relapse risk predictor (RRP) was constructed based on 16 CpG sites, demonstrating c-indexes of 0.667 and 0.677 in the training and test sets, respectively. The mortality risk predictor (MRP), comprising 53 CpG sites, exhibited c-indexes of 0.751 and 0.754 in the training and test sets, respectively. To validate the prognostic value of the predictors, we further analyzed two independent cohorts of Canadian (n = 42) and Nordic (n = 384) ALL patients. The external validation confirmed our findings, with the RRP achieving a c-index of 0.667 in the Canadian cohort, and the RRP and MRP achieving c-indexes of 0.529 and 0.621, respectively, in an independent Nordic cohort. The precision of the RRP and MRP models improved when incorporating traditional risk group data, underscoring the potential for synergistic integration of clinical prognostic factors. The MRP model also enabled the definition of a risk group with high rates of relapse and mortality. Our results demonstrate the potential of DNA methylation as a prognostic factor and a tool to refine risk stratification in pediatric ALL. This may lead to personalized treatment strategies based on epigenetic profiling.

Co-design of a paediatric oncology medicines database (ProCure) to support complex care provision for children with a hard-to-treat cancer

Objectives

Paediatric oncologists often encounter challenges when seeking compassionate access to off-label therapies for their patients. This study employed implementation science and co-design techniques to develop the ProCure medicines database, with the goal of streamlining the application process and addressing identified barriers in paediatric oncology.

Methods

This study utilised an exploratory qualitative research design. Seventeen healthcare providers, including oncologists, nurse consultants, and allied health professionals, participated in semi-structured interviews guided by the Consolidated Framework for Implementation Research (CFIR) and a visual process map aid. Deductive qualitative data analysis, according to the CFIR constructs, identified key barriers and facilitators. Collaborative design sessions engaged multidisciplinary teams to develop the ProCure beta version.

Results

Barriers to off-label therapy access included resource-intensive applications, time sensitive decision-making, and complex pharmaceutical information. Facilitators included Drug Access Navigators, Molecular Tumour Boards, and a multi-disciplinary approach. ProCure addressed end-user needs by centralising medicines information. Additional features suggested by healthcare providers included blood-brain-barrier penetrability data and successful application examples.

Conclusion

ProCure represents a promising solution to the challenges paediatric oncologists face in accessing off-label therapies. By centralising information, it simplifies the application process, aids decision-making, and promotes a collaborative approach to patient care. The potential of the database to stream and enhance off-label therapy access underscores its relevance in improving paediatric oncology practise. Further research and implementation efforts are warranted to assess ProCure's real-world impact and refine its features based on user feedback.

Molecular and clinicopathologic characteristics of CNS embryonal tumors with BRD4::LEUTX fusion

Central nervous system (CNS) embryonal tumors are a heterogeneous group of high-grade malignancies, and the increasing clinical use of methylation profiling and next-generation sequencing has led to the identification of molecularly distinct subtypes. One proposed tumor type, CNS tumor with BRD4::LEUTX fusion, has been described. As only a few CNS tumors with BRD4::LEUTX fusions have been described, we herein characterize a cohort of 9 such cases (4 new, 5 previously published) to further describe their clinicopathologic and molecular features. We demonstrate that CNS embryonal tumor with BRD4::LEUTX fusion comprises a well-defined methylation class/cluster. We find that patients are young (4 years or younger), with large tumors at variable locations, and frequently with evidence of leptomeningeal/cerebrospinal fluid (CSF) dissemination. Histologically, tumors were highly cellular with high-grade embryonal features. Immunohistochemically, 5/5 cases showed synaptophysin and 4/5 showed OLIG2 expression, thus overlapping with CNS neuroblastoma, FOXR2-activated. DNA copy number profiles were generally flat; however, two tumors had chromosome 1q gains. No recurring genomic changes, besides the presence of the fusion, were found. The LEUTX portion of the fusion transcript was constant in all cases assessed, while the BRD4 portion varied but included a domain with proto-oncogenic activity in all cases. Two patients with clinical follow up available had tumors with excellent response to chemotherapy. Two of our patients were alive without evidence of recurrence or progression after gross total resection and chemotherapy at 16 and 33 months. One patient relapsed, and the last of our four patients died of disease one month after diagnosis. Overall, this case series provides additional evidence for this as a distinct tumor type defined by the presence of a specific fusion as well as a distinct DNA methylation signature. Studies on larger series are required to further characterize these tumors.

Pediatric CNS tumors and 2021 WHO classification: what do oncologists need from pathologists?

The fifth edition of the WHO Classification of Tumors of the Central Nervous System (CNS), published in 2021, established new approaches to both CNS tumor nomenclature and grading, emphasizing the importance of integrated diagnoses and layered reports. This edition increased the role of molecular diagnostics in CNS tumor classification while still relying on other established approaches such as histology and immunohistochemistry. Moreover, it introduced new tumor types and subtypes based on novel diagnostic technologies such as DNA methylome profiling. Over the past decade, molecular techniques identified numerous key genetic alterations in CSN tumors, with important implications regarding the understanding of pathogenesis but also for prognosis and the development and application of effective molecularly targeted therapies. This review summarizes the major changes in the 2021 fifth edition classification of pediatric CNS tumors, highlighting for each entity the molecular alterations and other information that are relevant for diagnostic, prognostic, or therapeutic purposes and that patients' and oncologists' need from a pathology report.

The evolutionary impact of childhood cancer on the human gene pool

Germline pathogenic variants associated with increased childhood mortality must be subject to natural selection. Here, we analyze publicly available germline genetic metadata from 4,574 children with cancer [11 studies; 1,083 whole exome sequences (WES), 1,950 whole genome sequences (WGS), and 1,541 gene panel] and 141,456 adults [125,748 WES and 15,708 WGS]. We find that pediatric cancer predisposition syndrome (pCPS) genes [n = 85] are highly constrained, harboring only a quarter of the loss-of-function variants that would be expected. This strong indication of selective pressure on pCPS genes is found across multiple lines of germline genomics data from both pediatric and adult cohorts. For six genes [ELP1, GPR161, VHL and SDHA/B/C], a clear lack of mutational constraint calls the pediatric penetrance and/or severity of associated cancers into question. Conversely, out of 23 known pCPS genes associated with biallelic risk, two [9%, DIS3L2 and MSH2] show significant constraint, indicating that they may monoallelically increase childhood cancer risk. In summary, we show that population genetic data provide empirical evidence that heritable childhood cancer leads to natural selection powerful enough to have significantly impacted the present-day gene pool.

Phase I/II Study of the WEE1 Inhibitor Adavosertib (AZD1775) in Combination with Carboplatin in Children with Advanced Malignancies: Arm C of the AcSé-ESMART Trial

PURPOSE

AcSé-ESMART Arm C aimed to define the recommended dose and activity of the WEE1 inhibitor adavosertib in combination with carboplatin in children and young adults with molecularly enriched recurrent/refractory malignancies.

PATIENTS AND METHODS

Adavosertib was administered orally, twice every day on Days 1 to 3 and carboplatin intravenously on Day 1 of a 21-day cycle, starting at 100 mg/m2/dose and AUC 5, respectively. Patients were enriched for molecular alterations in cell cycle and/or homologous recombination (HR).

RESULTS

Twenty patients (median age: 14.0 years; range: 3.4-23.5) were included; 18 received 69 treatment cycles. Dose-limiting toxicities were prolonged grade 4 neutropenia and grade 3/4 thrombocytopenia requiring transfusions, leading to two de-escalations to adavosertib 75 mg/m2/dose and carboplatin AUC 4; no recommended phase II dose was defined. Main treatment-related toxicities were hematologic and gastrointestinal. Adavosertib exposure in children was equivalent to that in adults; both doses achieved the cell kill target. Overall response rate was 11% (95% confidence interval, 0.0-25.6) with partial responses in 2 patients with neuroblastoma. One patient with medulloblastoma experienced unconfirmed partial response and 5 patients had stable disease beyond four cycles. Seven of these eight patients with clinical benefit had alterations in HR, replication stress, and/or RAS pathway genes with or without TP53 alterations, whereas TP53 pathway alterations alone (8/10) or no relevant alterations (2/10) were present in the 10 patients without benefit.

CONCLUSIONS

Adavosertib-carboplatin combination exhibited significant hematologic toxicity. Activity signals and identified potential biomarkers suggest further studies with less hematotoxic DNA-damaging therapy in molecularly enriched pediatric cancers.

Evaluation of Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA) Samples from Advanced Non-Small Cell Lung Cancer for Whole Genome, Whole Exome and Comprehensive Panel Sequencing

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is often the only source of tumor tissue from patients with advanced, inoperable lung cancer. EBUS-TBNA aspirates are used for the diagnosis, staging, and genomic testing to inform therapy options. Here we extracted DNA and RNA from 220 EBUS-TBNA aspirates to evaluate their suitability for whole genome (WGS), whole exome (WES), and comprehensive panel sequencing. For a subset of 40 cases, the same nucleic acid extraction was sequenced using WGS, WES, and the TruSight Oncology 500 assay. Genomic features were compared between sequencing platforms and compared with those reported by clinical testing. A total of 204 aspirates (92.7%) had sufficient DNA (100 ng) for comprehensive panel sequencing, and 109 aspirates (49.5%) had sufficient material for WGS. Comprehensive sequencing platforms detected all seven clinically reported tier 1 actionable mutations, an additional three (7%) tier 1 mutations, six (15%) tier 2-3 mutations, and biomarkers of potential immunotherapy benefit (tumor mutation burden and microsatellite instability). As expected, WGS was more suited for the detection and discovery of emerging novel biomarkers of treatment response. WGS could be performed in half of all EBUS-TBNA aspirates, which points to the enormous potential of EBUS-TBNA as source material for large, well-curated discovery-based studies for novel and more effective predictors of treatment response. Comprehensive panel sequencing is possible in the vast majority of fresh EBUS-TBNA aspirates and enhances the detection of actionable mutations over current clinical testing.

From the identification of actionable molecular targets to the generation of faithful neuroblastoma patient-derived preclinical models

BACKGROUND

Neuroblastoma (NB) represents the most frequent and aggressive form of extracranial solid tumor of infants. Although the overall survival of patients with NB has improved in the last years, more than 50% of high-risk patients still undergo a relapse. Thus, in the era of precision/personalized medicine, the need for high-risk NB patient-specific therapies is urgent.

METHODS

Within the PeRsonalizEd Medicine (PREME) program, patient-derived NB tumors and bone marrow (BM)-infiltrating NB cells, derived from either iliac crests or tumor bone lesions, underwent to histological and to flow cytometry immunophenotyping, respectively. BM samples containing a NB cells infiltration from 1 to 50 percent, underwent to a subsequent NB cells enrichment using immune-magnetic manipulation. Then, NB samples were used for the identification of actionable targets and for the generation of 3D/tumor-spheres and Patient-Derived Xenografts (PDX) and Cell PDX (CPDX) preclinical models.

RESULTS

Eighty-four percent of NB-patients showed potentially therapeutically targetable somatic alterations (including point mutations, copy number variations and mRNA over-expression). Sixty-six percent of samples showed alterations, graded as "very high priority", that are validated to be directly targetable by an approved drug or an investigational agent. A molecular targeted therapy was applied for four patients, while a genetic counseling was suggested to two patients having one pathogenic germline variant in known cancer predisposition genes. Out of eleven samples implanted in mice, five gave rise to (C)PDX, all preserved in a local PDX Bio-bank. Interestingly, comparing all molecular alterations and histological and immunophenotypic features among the original patient's tumors and PDX/CPDX up to second generation, a high grade of similarity was observed. Notably, also 3D models conserved immunophenotypic features and molecular alterations of the original tumors.

CONCLUSIONS

PREME confirms the possibility of identifying targetable genomic alterations in NB, indeed, a molecular targeted therapy was applied to four NB patients. PREME paves the way to the creation of clinically relevant repositories of faithful patient-derived (C)PDX and 3D models, on which testing precision, NB standard-of-care and experimental medicines.

Molecular-guided therapy for the treatment of patients with relapsed and refractory childhood cancers: a Beat Childhood Cancer Research Consortium trial

BACKGROUND

Children with relapsed central nervous system (CNS tumors), neuroblastoma, sarcomas, and other rare solid tumors face poor outcomes. This prospective clinical trial examined the feasibility of combining genomic and transcriptomic profiling of tumor samples with a molecular tumor board (MTB) approach to make real‑time treatment decisions for children with relapsed/refractory solid tumors.

METHODS

Subjects were divided into three strata: stratum 1-relapsed/refractory neuroblastoma; stratum 2-relapsed/refractory CNS tumors; and stratum 3-relapsed/refractory rare solid tumors. Tumor samples were sent for tumor/normal whole-exome (WES) and tumor whole-transcriptome (WTS) sequencing, and the genomic data were used in a multi-institutional MTB to make real‑time treatment decisions. The MTB recommended plan allowed for a combination of up to 4 agents. Feasibility was measured by time to completion of genomic sequencing, MTB review and initiation of treatment. Response was assessed after every two cycles using Response Evaluation Criteria in Solid Tumors (RECIST). Patient clinical benefit was calculated by the sum of the CR, PR, SD, and NED subjects divided by the sum of complete response (CR), partial response (PR), stable disease (SD), no evidence of disease (NED), and progressive disease (PD) subjects. Grade 3 and higher related and unexpected adverse events (AEs) were tabulated for safety evaluation.

RESULTS

A total of 186 eligible patients were enrolled with 144 evaluable for safety and 124 evaluable for response. The average number of days from biopsy to initiation of the MTB-recommended combination therapy was 38 days. Patient benefit was exhibited in 65% of all subjects, 67% of neuroblastoma subjects, 73% of CNS tumor subjects, and 60% of rare tumor subjects. There was little associated toxicity above that expected for the MGT drugs used during this trial, suggestive of the safety of utilizing this method of selecting combination targeted therapy.

CONCLUSIONS

This trial demonstrated the feasibility, safety, and efficacy of a comprehensive sequencing model to guide personalized therapy for patients with any relapsed/refractory solid malignancy. Personalized therapy was well tolerated, and the clinical benefit rate of 65% in these heavily pretreated populations suggests that this treatment strategy could be an effective option for relapsed and refractory pediatric cancers.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02162732. Prospectively registered on June 11, 2014.

Overview of modern genomic tools for diagnosis and precision therapy of childhood solid cancers

PURPOSE OF REVIEW

The application of technology and computational analyses to generate new data types from pediatric solid cancers is transforming diagnostic accuracy. This review provides an overview of such new capabilities in the pursuit of improved treatment for essentially rare and underserved diseases that are the highest cause of mortality in children over one year of age. Sophisticated ways of identifying therapeutic vulnerabilities for highly personalized treatment are presented alongside cutting-edge disease response monitoring by liquid biopsy.

RECENT FINDINGS

Precision molecular profiling data are now being combined with conventional pathology-based evaluation of pediatric cancer tissues. The resulting diagnostic information can be used to guide therapeutic decision-making, including the use of small molecule inhibitors and of immunotherapies. Integrating somatic and germline variant profiles constitutes a critical component of this emerging paradigm, as does tissue-of-origin derivation from methylation profiling, and rapid screening of potential therapies. These new approaches are poised for use in disease response and therapy resistance monitoring.

SUMMARY

The integration of clinical molecular profiling data with pathology can provide a highly precise diagnosis, identify therapeutic vulnerabilities, and monitor patient responses, providing next steps toward precision oncology for improved outcomes, including reducing lifelong treatment-related sequelae.

Implementing data on targeted therapy from the INFORM registry platform for children with relapsed cancer in Sweden

Background

Advances in treatment of childhood malignancies have improved overall cure rates to 80%. Nevertheless, cancer is still the most common cause of childhood mortality in Sweden. The prognosis is particularly poor for relapse of high-risk malignancies. In the international INFORM registry, tumor tissue from patients with relapsed, refractory, or progressive pediatric cancer as well as from very-high risk primary tumors is biologically characterized using next-generation sequencing to identify possible therapeutic targets. We analyzed data from Swedish children included in the INFORM registry concerning patient characteristics, survival, sequencing results and whether targeted treatment was administered to the children based on the molecular findings.

Methods

A registry-based descriptive analysis of 184 patients included in the INFORM registry in Sweden during 2016-2021.

Results

The most common diagnoses were soft tissue and bone sarcomas followed by high grade gliomas [including diffuse intrinsic pontine glioma (DIPG)]. Complete molecular analysis was successful for 203/212 samples originating from 184 patients. In 88% of the samples, at least one actionable target was identified. Highly prioritized targets, according to a preset scale, were identified in 48 (24%) samples from 40 patients and 24 of these patients received matched targeted treatment but only six children within a clinical trial. No statistically significant benefit in terms of overall survival or progression free survival was observed between children treated with matched targeted treatment compared to all others.

Conclusion

This international collaborative study demonstrate feasibility regarding sequencing of pediatric high-risk tumors providing molecular data regarding potential actionable targets to clinicians. For a few individuals the INFORM analysis was of utmost importance and should be regarded as a new standard of care with the potential to guide targeted therapy.

Prognostic DNA mutation and mRNA expression analysis of perineural invasion in oral squamous cell carcinoma

This study analyzed oral squamous cell carcinoma (OSCC) genomes and transcriptomes in relation to perineural invasion (PNI) and prognosis using Cancer Genome Atlas data and validated these results with GSE41613 data. Gene set enrichment analysis (GSEA), gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes were conducted. We identified 22 DNA mutations associated with both overall survival (OS) and PNI. Among them, TGFBR1 and RPS6KA4 mRNAs were overexpressed, while TYRO3 and GPR137 mRNAs were underexpressed in PNI patients. Among the 141 mRNA genes associated with both OS and PNI, we found overlap with PNI-related DNA mutations, including ZNF43, TEX10, TPSD1, and PSD3. In GSE41613 data, TGFBR1, RPS6KA4, TYRO3, GPR137, TEX10 and TPSD1 mRNAs were expressed differently according to the prognosis. The 22 DNA-mutated genes clustered into nervous system development, regulation of DNA-templated transcription, and transforming growth factor beta binding. GSEA analysis of mRNAs revealed upregulation of hallmarks epithelial mesenchymal transition (EMT), TNFα signaling via NF-κB, and IL2 STAT5 signaling. EMT upregulation aligned with the TGFBR1 DNA mutation, supporting its significance in PNI. These findings suggest a potential role of PNI genes in the prognosis of OSCC, providing insights for diagnosis and treatment of OSCC.

Clinical Impact of Comprehensive Molecular Profiling in Adolescents and Young Adults with Sarcoma

Sarcomas are a heterogenous group of tumours that commonly carry poor prognosis with limited therapeutic options. Adolescents and young adults (AYAs) with sarcoma are a unique and understudied patient population that have only achieved modest survival gains compared to other groups. We present our institutional experience of AYAs with sarcoma who underwent comprehensive molecular profiling (CMP) via either large-panel targeted DNA sequencing or whole genome and transcriptome sequencing and evaluated the feasibility and clinical impact of this approach. Genomic variants detected were determined to be clinically relevant and actionable following evaluation by the Molecular Tumour Board. Clinicians provided feedback regarding the utility of testing three months after reporting. Twenty-five patients who were recruited for CMP are included in this analysis. The median time from consent to final molecular report was 45 days (interquartile range: 37-57). Potentially actionable variants were detected for 14 patients (56%), and new treatment recommendations were identified for 12 patients (48%). Pathogenic germline variants were identified in three patients (12%), and one patient had a change in diagnosis. The implementation of CMP for AYAs with sarcoma is clinically valuable, feasible, and should be increasingly integrated into routine clinical practice as technologies and turnaround times continue to improve.

BARD1 germline variants induce haploinsufficiency and DNA repair defects in neuroblastoma

BACKGROUND

High-risk neuroblastoma is a complex genetic disease that is lethal in more than 50% of patients despite intense multimodal therapy. Through genome-wide association studies (GWAS) and next-generation sequencing, we have identified common single nucleotide polymorphisms and rare, pathogenic or likely pathogenic germline loss-of-function variants in BARD1 enriched in neuroblastoma patients. The functional implications of these findings remain poorly understood.

METHODS

We correlated BARD1 genotype with expression in normal tissues and neuroblastomas, along with the burden of DNA damage in tumors. To validate the functional consequences of germline pathogenic or likely pathogenic BARD1 variants, we used CRISPR-Cas9 to generate isogenic neuroblastoma (IMR-5) and control (RPE1) cellular models harboring heterozygous BARD1 loss-of-function variants (R112*, R150*, E287fs, and Q564*) and quantified genomic instability in these cells via next-generation sequencing and with functional assays measuring the efficiency of DNA repair.

RESULTS

Both common and rare neuroblastoma-associated BARD1 germline variants were associated with lower levels of BARD1 mRNA and an increased burden of DNA damage. Using isogenic heterozygous BARD1 loss-of-function variant cellular models, we functionally validated this association with inefficient DNA repair. BARD1 loss-of-function variant isogenic cells exhibited reduced efficiency in repairing Cas9-induced DNA damage, ineffective RAD51 focus formation at DNA double-strand break sites, and enhanced sensitivity to cisplatin and poly (ADP-ribose) polymerase (PARP) inhibition both in vitro and in vivo.

CONCLUSIONS

Taken together, we demonstrate that germline BARD1 variants disrupt DNA repair fidelity. This is a fundamental molecular mechanism contributing to neuroblastoma initiation that may have important therapeutic implications.

Germline pathogenic variants in neuroblastoma patients are enriched in BARD1 and predict worse survival

BACKGROUND

Neuroblastoma is an embryonal cancer of the developing sympathetic nervous system. The genetic contribution of rare pathogenic or likely pathogenic germline variants in patients without a family history remains unclear.

METHODS

Germline DNA sequencing was performed on 786 neuroblastoma patients. The frequency of rare cancer predisposition gene pathogenic or likely pathogenic variants in patients was compared with 2 cancer-free control cohorts. Matched tumor DNA sequencing was evaluated for second hits, and germline DNA array data from 5585 neuroblastoma patients and 23 505 cancer-free control children were analyzed to identify rare germline copy number variants. Patients with germline pathogenic or likely pathogenic variants were compared with those without to test for association with clinical characteristics, tumor features, and survival.

RESULTS

We observed 116 pathogenic or likely pathogenic variants involving 13.9% (109 of 786) of neuroblastoma patients, representing a statistically significant excess burden compared with cancer-free participants (odds ratio [OR] = 1.60, 95% confidence interval [CI] = 1.27 to 2.00). BARD1 harbored the most statistically significant enrichment of pathogenic or likely pathogenic variants (OR = 32.30, 95% CI = 6.44 to 310.35). Rare germline copy number variants disrupting BARD1 were identified in patients but absent in cancer-free participants (OR = 29.47, 95% CI = 1.52 to 570.70). Patients harboring a germline pathogenic or likely pathogenic variant had a worse overall survival compared with those without (P = 8.6 x 10-3).

CONCLUSIONS

BARD1 is an important neuroblastoma predisposition gene harboring both common and rare germline pathogenic or likely pathogenic variations. The presence of any germline pathogenic or likely pathogenic variant in a cancer predisposition gene was independently predictive of worse overall survival. As centers move toward paired tumor-normal sequencing at diagnosis, efforts should be made to centralize data and provide an infrastructure to support cooperative longitudinal prospective studies of germline pathogenic variation.