Associations between birth defects with neural crest cell origins and pediatric embryonal tumors

BACKGROUND

There are few assessments evaluating associations between birth defects with neural crest cell developmental origins (BDNCOs) and embryonal tumors, which are characterized by undifferentiated cells having a molecular profile similar to neural crest cells. The effect of BDNCOs on embryonal tumors was estimated to explore potential shared etiologic pathways and genetic origins.

METHODS

With the use of a multistate, registry-linkage cohort study, BDNCO-embryonal tumor associations were evaluated by generating hazard ratios (HRs) and 95% confidence intervals (CIs) with Cox regression models. BDNCOs consisted of ear, face, and neck defects, Hirschsprung disease, and a selection of congenital heart defects. Embryonal tumors included neuroblastoma, nephroblastoma, and hepatoblastoma. Potential HR modification (HRM) was investigated by infant sex, maternal race/ethnicity, maternal age, and maternal education.

RESULTS

The risk of embryonal tumors among those with BDNCOs was 0.09% (co-occurring n = 105) compared to 0.03% (95% CI, 0.03%-0.04%) among those without a birth defect. Children with BDNCOs were 4.2 times (95% CI, 3.5-5.1 times) as likely to be diagnosed with an embryonal tumor compared to children born without a birth defect. BDNCOs were strongly associated with hepatoblastoma (HR, 16.1; 95% CI, 11.3-22.9), and the HRs for neuroblastoma (3.1; 95% CI, 2.3-4.2) and nephroblastoma (2.9; 95% CI, 1.9-4.4) were elevated. There was no notable HRM by the aforementioned factors.

CONCLUSIONS

Children with BDNCOs are more likely to develop embryonal tumors compared to children without a birth defect. Disruptions of shared developmental pathways may contribute to both phenotypes, which could inform future genomic assessments and cancer surveillance strategies of these conditions.

Lipid Metabolic Reprogramming in Embryonal Neoplasms with MYCN Amplification

Tumor cells reprogram their metabolism, including glucose, glutamine, nucleotide, lipid, and amino acids to meet their enhanced energy demands, redox balance, and requirement of biosynthetic substrates for uncontrolled cell proliferation. Altered lipid metabolism in cancer provides lipids for rapid membrane biogenesis, generates the energy required for unrestricted cell proliferation, and some of the lipids act as signaling pathway mediators. In this review, we focus on the role of lipid metabolism in embryonal neoplasms with MYCN dysregulation. We specifically review lipid metabolic reactions in neuroblastoma, retinoblastoma, medulloblastoma, Wilms tumor, and rhabdomyosarcoma and the possibility of targeting lipid metabolism. Additionally, the regulation of lipid metabolism by the MYCN oncogene is discussed.

Investigation of 11p15.5 Methylation Defects Associated with Beckwith-Wiedemann Spectrum and Embryonic Tumor Risk in Lateralized Overgrowth Patients

The Beckwith-Wiedemann spectrum (BWSp) ranges from isolated lateralized overgrowth (ILO) to classic phenotypes. In this broad clinical spectrum, an epigenetic alteration on chromosome 11p15.5 can be detected. The risk for embryonal tumors is high, especially in patients with lateralized overgrowth (LO). The aim of this study is to investigate epigenetic alterations in 11p15.5 and tumor risk in 87 children with LO. The methylation level of 11p15.5 was examined in the blood of all patients and in skin samples or buccal swabs from 40 patients with negative blood tests; 63.2% of patients were compatible with the ILO phenotype, 18.4% were atypical, and 18.4% were classic. The molecular diagnosis rate was 81.2% for the atypical and classic phenotypes, and 10.9% for the ILO phenotype. In patients with epigenetic alterations, LO was statistically significantly more severe than in test negatives. Tumors developed in six (6.9%) of the total 87 patients with LO; four belonged to the atypical or classical phenotype (12.5%) and two to ILO (3.5%). Three of the four patients with atypical/classical phenotypes had pUPD11, one had IC1-GOM alteration, and two ILO patients were negative. We conclude that LO patients should be monitored for tumor risk even if their epigenetic tests are negative.

Post-Compulsory Education in Teenagers and Young Adults Treated for Brain Tumors in Childhood: A Swedish Nationwide Registry-Based Study

The risk of late complications after a brain tumor in childhood is high. Both the tumor itself and the treatments give rise to sequelae that affect daily life activities. In this registry study, we explored post-compulsory education, i.e., further education following the nine compulsory years in school, in 452 cases born 1988-1996 and diagnosed with a brain tumor before their fifteenth birthday. They were compared with 2188 individual controls who were not treated for cancer. Significantly fewer teenagers and young adults treated for brain tumors in childhood attended high school or university compared with controls, especially individuals treated for embryonal tumors or optic pathway gliomas. A significantly larger proportion of subjects treated for embryonal tumors and craniopharyngiomas attended folk high schools, a type of post-compulsory school with a more accessible learning environment. For both cases and controls, we observed a positive correlation between parental education levels and attendance in high school and university. In our previous studies we have shown that children treated for brain tumors, as a group, tend to perform worse during their last year of compulsory school compared with their peers, and the current study confirms that these differences remain over time.

Immunohistochemical assessment and clinical, histopathologic, and molecular correlates of membranous somatostatin type-2A receptor expression in high-risk pediatric central nervous system tumors

INTRODUCTION

177Lu-DOTATATE, a radionuclide therapy that binds somatostatin type-2A receptors (SST2A), has demonstrated efficacy in neuroendocrine tumors and evidence of central nervous system (CNS) penetration, supporting potential expansion within pediatric neuro-oncology. Understanding the prevalence of SST2A expression across pediatric CNS tumors is essential to identify patients who may benefit from somatostatin receptor-targeted therapy and to further elucidate the oncogenic role of SST2A.

METHODS

SST2A immunohistochemistry (IHC) was performed on tumor specimens and interpreted by an experienced pathologist (blinded), utilizing semi-quantitative scoring of membranous expression within viable tumor. Immunoreactive cell percentage was visually scored as 0 (none), 1 (<10%), 2 (10-50%), 3 (51-80%), or 4 (>80%). Staining intensity was scored as 0 (none), 1 (weak), 2 (moderate), or 3 (strong). Combined scores for each specimen were calculated by multiplying percent immunoreactivity and staining intensity values (Range: 0-12).

RESULTS

A total of 120 tumor samples from 114 patients were analyzed. Significant differences in SST2A IHC scores were observed across histopathologic diagnoses, with consistently high scores in medulloblastoma (mean ± SD: 7.5 ± 3.6 [n=38]) and meningioma (5.7 ± 3.4 [n=15]), compared to minimal or absent expression in ATRT (0.3 ± 0.6 [n=3]), ETMR (1.0 ± 0 [n=3]), ependymoma (grades I-III; 0.2 ± 0.7 [n=27]), and high-grade glioma (grades III-IV; 0.4 ± 0.7 [n=23]). Pineoblastoma (3.8 ± 1.5 [n=4]) and other embryonal tumors (2.0 ± 4.0 [n=7]) exhibited intermediate, variable expression. Among medulloblastomas, SST2A IHC scores were higher in non-SHH (8.5 ± 3.1) than SHH (5.0 ± 3.3) molecular subgroups (p=0.033). In a subset of paired primary and recurrent specimens from four patients, SST2A IHC scores remained largely unchanged.

DISCUSSION

High membranous SST2A expression was demonstrated in medulloblastoma, meningioma, and some rarer embryonal tumors with potential diagnostic, biologic, and therapeutic implications. Somatostatin receptor-targeted therapy such as 177Lu-DOTATATE deserves further investigation in these highly SST2A-expressing pediatric CNS tumors.

Acute Hematological Toxicity during Cranio-Spinal Proton Therapy in Pediatric Brain Embryonal Tumors

BACKGROUND

Embryonal tumors represent a heterogeneous entity of brain tumors that need a multidisciplinary treatment including cranio-spinal irradiation (CSI), with a known impact on the acute toxicity. Proton therapy (PT) boasts a reduction in acute hematological toxicity.

METHODS

We retrospectively examined 20 pediatric patients affected by high-risk medulloblastoma and other rare embryonal brain tumors subjected to CSI with PT from September 2016 to April 2020. Before CSI, all patients received induction chemotherapy, and three patients additionally received two high-dose courses with thiotepa, followed by an autologous haemopoietic stem cell transplantation. We recorded the total white blood cell count, absolute neutrophil count, platelets, and hemoglobin levels for all patients during PT.

RESULTS

Leucocytes and neutrophils decreased directly after the beginning of treatment, reaching a complete recovery at the end of treatment. Hemoglobin values remained constant over the treatment course. The median platelet value decreased until reaching a plateau around halfway through therapy, followed by a slow increase. No cases of febrile neutropenia or severe infections were reported. No treatment discontinuation due to hematological toxicity was necessary.

CONCLUSIONS

CSI with PT was proven to be safe in this setting of pediatric patients. Our study showed that despite all patients having undergone chemotherapy prior to irradiation, no serious hematological toxicity was reported at the end of the treatment with PT, and, therefore, no treatment was discontinued or delayed.

Investigation of (epi)genotype causes and follow-up manifestations in the patients with classical and atypical phenotype of Beckwith-Wiedemann spectrum

Beckwith-Wiedemann syndrome (BWS) is a genomic imprinting disorder, characterized by macroglossia, abdominal wall defects, lateralized overgrowth, and predisposition to embryonal tumors. It is caused by the defect of imprinted genes on chromosome 11p15.5, regulated by imprinting control (IC) domains, IC1, and IC2. Rarely, CDKN1C and chromosomal changes can be detected. The aim of this study is to retrospectively evaluate 55 patients with BWS using the new diagnostic criteria developed by the BWS consensus, and to investigate (epi)genetic changes and follow-up findings in classic and atypical phenotypes. Loss of methylation in IC2 region (IC2-LoM), 11p15.5 paternal uniparental disomy (pUPD11), and methylation gain in IC1 region (IC1-GoM) are detected in 31, eight, and five patients, respectively. Eleven patients have had no molecular defects. Thirty-five patients are classified as classical and 20 as atypical phenotype. Patients with classical phenotype are more frequent in the IC2-LoM (25/31), while patients with atypical phenotype are common in the pUPD11 group (5/8). Malignant tumors have developed in six patients (10.9%); three of these patients have IC1-GoM, two pUPD11, one IC2-LoM genotype, and four an atypical phenotype. We observed that the face was round in the infantile period and elongated as the child grew-up, developing prognathism and becoming asymmetrical if hemi-macroglossia was present in the classical phenotype. These findings were mild in the atypical phenotype. These results support the importance of using the new diagnostic criteria to facilitate the diagnosis of patients with atypical phenotype who have higher tumors risk. This study also provides important information about facial gestalt.

In vitro Modeling of Embryonal Tumors

A subset of pediatric tumors affects very young children and are thought to arise during fetal life. A common theme is that these embryonal tumors hijack developmental programs, causing a block in differentiation and, as a consequence, unrestricted proliferation. Embryonal tumors, therefore typically maintain an embryonic gene signature not found in their differentiated progeny. Still, the processes underpinning malignant transformation remain largely unknown, which is hampering therapeutic innovation. To gain more insight into these processes, in vitro and in vivo research models are indispensable. However, embryonic development is an extremely dynamic process with continuously changing cellular identities, making it challenging to define cells-of-origin. This is crucial for the development of representative models, as targeting the wrong cell or targeting a cell within an incorrect developmental time window can result in completely different phenotypes. Recent innovations in in vitro cell models may provide more versatile platforms to study embryonal tumors in a scalable manner. In this review, we outline different in vitro models that can be explored to study embryonal tumorigenesis and for therapy development.

Undernutrition and Pubertal Timing in Female Survivors of Medulloblastoma and Other Embryonal Tumors

CONTEXT

Children with brain tumors may have pubertal onset at an inappropriately young chronologic age. Hypothalamic-pituitary irradiation ≥18Gy has been found to be a risk factor; age at irradiation is associated with pubertal timing. However, the underlying mechanisms are unknown.

OBJECTIVE

To determine the impact of body mass index (BMI) and catch-up growth on pubertal timing in females treated for medulloblastoma and other embryonal tumors.

DESIGN, SETTING, AND PATIENTS

Retrospective cohort analysis of 90 female patients treated for medulloblastoma and other embryonal tumors at Dana-Farber Cancer Institute/Boston Children's Hospital from 1996 to 2016. Eighteen individuals met inclusion criteria, with a mean ± SD follow-up period of 11.9 ± 3.4 years.

MAIN OUTCOME MEASURES

Multiple linear regression models for age at pubertal onset and bone age discrepancy from chronologic age at pubertal onset assessed the joint influences of age at irradiation, hypothalamic irradiation dose, undernutrition duration, BMI standard deviation score (SDS) at pubertal onset, and catch-up BMI SDS.

RESULTS

The mean ± SD age of pubertal onset was 9.2 ± 1.3 years and hypothalamic radiation dose was 31.9 ± 9.9 Gy. There was a direct relationship between age at irradiation and age at pubertal onset (β = 0.323 ± 0.144 [standard error] year per year; P = 0.04) that was significantly attenuated after adjusting for BMI SDS at pubertal onset (P = 0.5) and catch-up BMI SDS (P = 0.08), suggesting that BMI is a mediator.

CONCLUSIONS

Both absolute and catch-up BMI SDS at pubertal onset are significant mediators of pubertal timing and bone age discrepancy in pediatric medulloblastoma and other embryonal tumors, and thus, are targetable risk factors to optimize pubertal timing.

Race, ethnicity, and socioeconomic differences in incidence of pediatric embryonal tumors in the United States

BACKGROUND

The etiology of childhood cancers and its social patterning remains largely unknown. Accounting for socioeconomic status (SES) when exploring the association between race/ethnicity and cancer incidence is necessary to better understand such etiology. We aimed to investigate differences in the incidence of embryonal tumors (ETs) by SES and race/ethnicity in the United States using population-based registries of the Surveillance, Epidemiology, and End Results (SEER) Program.

PROCEDURE

Children with ETs aged 0-19 years diagnosed between 2000 and 2015 were ascertained from the census tract-level SEER database. SES was measured using a tract-level composite index. Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) by SES quintile and race/ethnicity were estimated using multivariable Poisson regression models.

RESULTS

The majority of tumors had lower incidence among nonwhite children compared with non-Hispanic (NH) white children, after controlling for SES. NH blacks had a higher incidence of Wilms tumor than NH whites (IRR: 1.26; 95% CI, 1.13-1.39). There was an increasing linear trend (P = 0.0001) across increasing SES quintile for embryonal rhabdomyosarcoma after controlling for race/ethnicity. Effect modification by race/ethnicity of the relationship between SES and tumor incidence was observed for several groups. Hispanics had a significant, linear trend (P = 0.0005) in the incidence of Wilms tumor, while Asian/Pacific Islanders experienced a significant inverse trend (P = 0.0002).

CONCLUSIONS

Results from this study suggest differences in the incidence of several ETs by race/ethnicity and that these differences may be modified by SES. Investigation of potential risk factors that are socially patterned is warranted.

Supratentorial Embryonal Tumor in Adult Patient: Case Report and Literature Review

Embryonal tumors are the new nomenclature of the primitive neuroectodermal tumors or PNET. Their supratentorial location and their manifestation in adult population are not very frequent. Embryonal tumors are conformed from undifferentiated neuroepithelial cells that have the ability to show differentiation to several cell lines. Next is presented a case from an adult male patient with a clinical headache pictures and convulsions. With imaging study that shows a meningeal enhancement with frontal lobe infiltration with histopathological study of embryonic tumor with areas of glial differentiation.

Association between maternal education and survival after childhood cancer

BACKGROUND

Several nonbiological factors, including socioeconomic status indicators and other family characteristics, influence survival from childhood cancers. Our study explores the association between parental education and childhood cancer survival.

METHODS

The specialized Childhood Cancer Registry of the Piedmont region in Italy provided data on all the cases (aged 0-14) diagnosed with cancer in the period 1976-2011 who resided in the city of Turin (capital of the Piedmont region) at least once since 1971. Information on parental education was extracted from the Turin Longitudinal Study by record linkage. The association between parental educational level and survival was estimated using Cox regression.

RESULTS

The study included 949 children. We observed a disadvantage in the overall survival for children of less educated mothers. No such effect was observed for paternal education. The effect of maternal education was particularly strong for central nervous system tumors (hazard ratios, 2.9; 95% confidence interval, 1.1-8.0). A similar effect, though smaller in magnitude, was observed for leukemia and embryonal tumors, whereas the estimates for lymphoma were imprecise.

CONCLUSIONS

Our study shows an association between maternal educational level and survival in children with central nervous system tumors, a diagnosis that often requires long-lasting treatment and special care. Giving support to the families of affected children to provide them the optimal care has the potential to improve children's cancer treatment outcomes.

A 4-Year-Old Boy with Beckwith Wiedemann Syndrome (BWS)

OBJECTIVES

Molecular characterization of a patient with BWS.

CLINICAL PRESENTATION AND INTERVENTION

A 4-year-old boy with overgrowth (weight above 99th and height at 99th percentile) had longitudinal hemihypertrophy of the tongue and left cheek. In addition, there was a difference of one centimeter in the circumference of the left and right leg. Molecular genetic analysis revealed hypomethylation of KvDRM1 (LIT1) in the imprinting control region-2 (ICR2) on chromosome 11p15.5 and a normal methylation pattern of the H19-differentially methylated region (H19-DMR) in the ICR1. The estimated tumor risk was 1-5%.

CONCLUSION

This patient with clinical characteristics of BWS has an imprinting defect associated with a low risk of embryonal tumors.

Embryonal Tumors of the Central Nervous System in Children: The Era of Targeted Therapeutics

Embryonal tumors (ET) of the central nervous system (CNS) in children encompass a wide clinical spectrum of aggressive malignancies. Until recently, the overlapping morphological features of these lesions posed a diagnostic challenge and undermined discovery of optimal treatment strategies. However, with the advances in genomic technology and the outpouring of biological data over the last decade, clear insights into the molecular heterogeneity of these tumors are now well delineated. The major subtypes of ETs of the CNS in children include medulloblastoma, atypical teratoid rhabdoid tumor (ATRT), and embryonal tumors with multilayered rosettes (ETMR), which are now biologically and clinically characterized as different entities. These important developments have paved the way for treatments guided by risk stratification as well as novel targeted therapies in efforts to improve survival and reduce treatment burden.

Brain cancer genomics and epigenomics

Classically, brain cancers have been graded and diagnosed based on histology and risk stratified by clinical criteria. Recent advances in genomics and epigenomics have ushered in an era of defining cancers based on molecular criteria. These advances have increased our precision of identifying oncogenic driving events and, most importantly, increased our precision at predicting clinical outcome. For the first time in its history, the 2016 revision of the WHO Classification of Tumors of the Central Nervous System included molecular features as tumor classification criteria. Brain tumors can develop in the context of genetic cancer predisposition syndromes, such as Li-Fraumeni or Gorlin syndrome, but by far most commonly arise through the acquisition of somatic mutations and chromosome changes in the malignant cells. By taking a survey across this cancer landscape, certain themes emerge as being common events to drive cancer: DNA damage repair, genomic instability, mechanistic target of rapamycin pathway, sonic hedgehog pathway, hypoxia, and epigenetic dysfunction. Understanding these mechanisms is of paramount importance for improving targeted therapies, and for identifying the right patients for those therapies.

Inhibition of polo-like kinase 4 (PLK4): a new therapeutic option for rhabdoid tumors and pediatric medulloblastoma

Rhabdoid tumors (RT) are highly aggressive and vastly unresponsive embryonal tumors. They are the most common malignant CNS tumors in infants below 6 months of age. Medulloblastomas (MB) are embryonal tumors that arise in the cerebellum and are the most frequent pediatric malignant brain tumors. Despite the advances in recent years, especially for the most favorable molecular subtypes of MB, the prognosis of patients with embryonal tumors remains modest with treatment related toxicity dreadfully high. Therefore, new targeted therapies are needed. The polo-like kinase 4 (PLK4) is a critical regulator of centriole duplication and consequently, mitotic progression. We previously established that PLK4 is overexpressed in RT and MB. We also demonstrated that inhibiting PLK4 with a small molecule inhibitor resulted in impairment of proliferation, survival, migration and invasion of RT cells. Here, we showed in MB the same effects that we previously described for RT. We also demonstrated that PLK4 inhibition induced apoptosis, senescence and polyploidy in RT and MB cells, thereby increasing the susceptibility of cancer cells to DNA-damaging agents. In order to test the hypothesis that PLK4 is a CNS druggable target, we demonstrated efficacy with oral administration to an orthotropic xenograft model. Based on these results, we postulate that targeting PLK4 with small-molecule inhibitors could be a novel strategy for the treatment of RT and MB and that PLK4 inhibitors (PLK4i) might be promising agents to be used solo or in combination with cytotoxic agents.