Search

Advances in genome and tissue engineering have spurred significant progress and opportunity for innovation in cancer modeling. Human induced pluripotent stem cells (iPSCs) are an established and powerful tool to study cellular processes in the context of disease-specific genetic backgrounds; however, their application to cancer has been limited by the resistance of many transformed cells to undergo successful reprogramming. Here, we review the status of human iPSC modeling of solid tumors in the context of genetic engineering, including how base and prime editing can be incorporated into "bottom-up" cancer modeling, a term we coined for iPSC-based cancer models using genetic engineering to induce transformation. This approach circumvents the need to reprogram cancer cells while allowing for dissection of the genetic mechanisms underlying transformation, progression, and metastasis with a high degree of precision and control. We also discuss the strengths and limitations of respective engineering approaches and outline experimental considerations for establishing future models.

Top 30 loci associated with metastasis at diagnosis in the discovery set of 541 European osteosarcoma cases.

Relationship of variables to metastasis at diagnosis in the discovery set.

SNPs in the NFIB locus associated with metastasis at diagnosis with P{less than or equal to}1x10-5 in the discovery stage, and functionally annotated with information from the ENCODE and 1000 Genomes Project data.

Associations of the top GWAS and imputed SNP with metastasis at diagnosis in the discovery stage (European ancestry) by inheritance model.

Top genotyped SNP associations with metastasis at diagnosis in the discovery and all replication studies.

Supplementary Figure 1. Manhattan plot of the Discovery stage. SNPs in the NFIB risk locus are highlighted in green. Supplementary Figure 2. LD structure of the NFIB risk locus. Plot was made using the CEU population of the 1000 Genomes Project data with LDlink (ref 54). Supplementary Figure 3. Significant relationship between the genotype of the metastasis associated SNP rs7034162, and expression of NFIB and IGFBP5 in osteosarcoma cell lines and tumors. Significance is based on linear regression comparing the distribution of expression of NFIBbetween the TT homozygous non-risk genotype (combined N=34) of rs7034162 genotypes to the heterozygous risk AT (combined N=10) and the homozygous risk AA genotypes (combined N=2). The green triangle represents the expression levels in the OSA cell line, the blue circle is expression levels in the HOS cell line, and the red square the U2OS cell line expression. These analyses were based on the publically available genotype and expression data from 17 osteosarcoma cell lines and 29 osteosarcoma tumors (ref 20). Supplementary Figure 4. No significant relationship between the genotype of the metastasis associated SNP, rs7034162, and expression of protein-encoding genes FREM1, ZDHHC1, and MPDZ in the neighborhood of NFIB in osteosarcoma cell lines and tumors. Significance is based on linear regression comparing the distribution of expression of FREM1, ZDHHC1, and MPDZ between the TT homozygous non-risk genotype (combined N=34) of rs7034162 genotypes to the heterozygous risk AT (combined N=10) and the homozygous risk AA genotypes (combined N=2). The green triangle represents the expression levels in the OSA cell line, the blue circle is expression levels in the HOS cell line, and the red square the U2OS cell line expression. These analyses were based on the publically available genotype and expression data from 17 osteosarcoma cell lines and 29 osteosarcoma tumors (ref 20). Supplementary Figure 5. The human osteosarcoma cell lines, U2OS and HOS, had higher NFIB protein levels then OSA cells. NFIB levels were determined using immunoblot analysis in the OSA, HOS and U2OS cells both basal (A) and after treatment with siRNA against NFIB (B). Supplementary Figure 6. NFIB expression significantly correlates with IGFBP5 expression in osteosarcoma cell lines and tumors. Significance is based on linear regression comparing the expression levels of NFIB with the corresponding IGFBP5 expression levels. Supplementary Figure 7. Expression levels of IGFBP5 decreases after NFIB suppression of human osteosarcoma cell lines. IGFBP5 expression of OSA, HOS and U2OS cells was determined 48 hours after transfection with control siRNA (si-NEG) or siRNA targeting NFIB (si-NFIB). Graph showing relative expression compared to control treated U2OS cells. Supplementary Figure 8. A model of how the NFIB risk locus leads to changes in NFIB expression and potentially may affect osteosarcoma metastatic potential. The risk allele (right panel) leads to lowered expression of NFIB and NFIB-mediated lower expression of IGFPB5, which then leads to less IGFBP5-mediated inhibition of IGF-1 (right panel, grey arrows), leading to an increase in proliferation, survival and metastasis of osteosarcoma cells (right panel, black arrows). The reference allele (left panel) leads to both higher expression of NFIB and higher expression of NFIB-mediated IGFPB5. In turn, higher IGFBP5 levels leads to increased inhibition of IGF-1 (left panel, black arrows), leading to a decrease in proliferation, survival and metastasis of osteosarcoma cells (left panel, grey arrows). Supplementary Figure 9. Plot of the PCA Eigenvectors of the Discovery stage. Supplementary Figure 10. QQ-plot of the Discovery stage.

Description of participating case studies.

Supplemental Table 4. Gene lists identified in the clustering. Tab 1 Genes in Human clusters (n=7), mouse clusters (n=11), dog clusters (n=5), GSE212257 (n=14) Tab 2 Overlap counts of RNASEQ cluster lists. Tab 3 Overlap of human cluster 1 and human cluster 8 with LM22 signature

Supplemental Table 6. Gene Cluster Expression Summary Scores. Tab 1 Human GCESS values Tab 2 Mouse GCESS values Tab 3 Dog GCESS values Tab 4 GSE212257 GCESS values

Read Counts, mapping percentage and expressed gene count for all RNAseq samples. Tab 1 Human Tab 2 Dog Tab 3 Mouse

Supplementary methods contains additional information describing methods used and description of all supplemental data included. Supplemental Figures Supplemental Figure 1. Real human data clustered Supplemental Figure 2. Random human data clustered Supplemental Figure 3. Permuted human data clustered Supplemental Figure 4. Real mouse data clustered Supplemental Figure 5. Random mouse data clustered Supplemental Figure 6. Permuted mouse data clustered Supplemental Figure 7. Real dog data clustered Supplemental Figure 8. Random dog data clustered Supplemental Figure 9. Permuted dog data clustered Supplemental Figure 10. Examples of 4 immunohistochemistry groups Supplemental Figure 11. KM significance in real, random, and permuted human and dog datasets. Supplemental Figure 12. KM human cluster-1 Supplemental Figure 13. KM human cluster-4 Supplemental Figure 14. KM human cluster-8 Supplemental Figure 15. KM dog cluster-3 Supplemental Figure 16. GSE212257 Array cluster- 3 association with Outcome Supplemental Figure 17. GSE212257 Array cluster-5 association with Outcome Supplemental Figure 18. GSE212257 Array cluster-3 association with Metastasis Supplemental Figure 19. GSE212257 Array cluster-5 association with Metastasis Supplemental Figure 20. GSE212257 Array cluster-7 association with Metastasis Supplemental Figure 21. Cell Cycle GCESS plotted against Immune-1 and Immune-2 GCESS Supplemental Figure 22. Model depicting how immune cell components may be preventing the occurrence of metastasis in OS patients. Supplemental Figure 23. Flowchart of OS samples utilized in this work

Overall survival of patients with osteosarcoma (OS) has improved little in the past three decades, and better models for study are needed. OS is common in large dog breeds and is genetically inducible in mice, making the disease ideal for comparative genomic analyses across species. Understanding the level of conservation of intertumor transcriptional variation across species and how it is associated with progression to metastasis will enable us to more efficiently develop effective strategies to manage OS and to improve therapy. In this study, transcriptional profiles of OS tumors and cell lines derived from humans (n = 49), mice (n = 103), and dogs (n = 34) were generated using RNA sequencing. Conserved intertumor transcriptional variation was present in tumor sets from all three species and comprised gene clusters associated with cell cycle and mitosis and with the presence or absence of immune cells. Further, we developed a novel gene cluster expression summary score (GCESS) to quantify intertumor transcriptional variation and demonstrated that these GCESS values associated with patient outcome. Human OS tumors with GCESS values suggesting decreased immune cell presence were associated with metastasis and poor survival. We validated these results in an independent human OS tumor cohort and in 15 different tumor data sets obtained from The Cancer Genome Atlas. Our results suggest that quantification of immune cell absence and tumor cell proliferation may better inform therapeutic decisions and improve overall survival for OS patients.Significance: This study offers new tools to quantify tumor heterogeneity in osteosarcoma, identifying potentially useful prognostic biomarkers for metastatic progression and survival in patients. Cancer Res; 78(2); 326–37. ©2017 AACR.

Sample clinical, outcome and sequencing metadata for human mouse and dog samples.

Supplemental Table 7. Immunohistochemistry validation of Immune 1 and Immune 2 GCESS

Supplemental Table 5. IPA enrichment analyses of recurrent human gene clusters.

Tumor Counts, number of Outcome events and GCESS Outcome threshold values

ImportanceAcute lymphoblastic leukemia (ALL) is the most common form of pediatric cancer, and a leading cause of death in children. Understanding the causes of pediatric ALL is necessary to enable early detection and prevention; congenital cytomegalovirus (cCMV) has recently been identified as a potential moderate-to-strong factor associated with risk for ALL.ObjectiveTo compare the prevalence of cCMV infection between ALL cases and matched controls.Design, Setting, and ParticipantsIn this population-based case-control study of ALL cases and matched controls, cases consisted of children aged 0 to 14 years between 1987 and 2014 with an ALL diagnosis identified through the Michigan Cancer Surveillance Program and born in Michigan on or after October 1, 1987. Cancer-free controls were identified by the Michigan BioTrust for Health and matched on age, sex, and mother’s race and ethnicity. Data were analyzed from November to May 2022.ExposurescCMV infection measured by quantitative polymerase chain reaction in newborn dried blood spots.Main Outcomes and MeasuresALL diagnosed in children aged 0 to 14 years.ResultsA total of 1189 ALL cases and 4756 matched controls were included in the study. Bloodspots were collected from participants at birth, and 3425 (57.6%) participants were male. cCMV was detected in 6 ALL cases (0.5%) and 21 controls (0.4%). There was no difference in the odds of cCMV infection comparing ALL cases with controls (odds ratio, 1.30; 95% CI, 0.52-3.24). Immunophenotype was available for 536 cases (45.1%) and cytogenetic data for 127 (27%). When stratified by subtype characteristics, hyperdiploid ALL (74 cases) was associated with 6.26 times greater odds of cCMV infection compared with unmatched controls (95% CI, 1.44-27.19).Conclusions and RelevanceIn this case-control study of cCMV and pediatric ALL, cCMV was associated with increased risk of hyperdiploid ALL. These findings encourage continued research.

OBJECTIVES/GOALS: We leverage the disparate incidence of Ewing sarcoma (ES) between European (EUR) and African (AFR) ancestry to study ES tumorigenesis in iPSC-derived cells from donors with a range of AFR ancestry via functional / molecular profiling. Integrated multi-omics analysis furthers explore local regulatory networks in pursuit of novel drug targets of ES. METHODS/STUDY POPULATION: In our pilot, eight induced pluripotent stem cell lines were obtained, differentiated into neural crest cells, and then transduced with a lentivirus expressing GFP-2A-EWS/FLI1. We compared wild type (WT) to EWS-FLI1-induced cells and then compared cell survival, gene expression, and EWS-FLI1 binding differences at varying levels of EUR / AFR ancestry admixture. We will build on this pilot data by expanding the number of cell lines and measuring chromatin state. Subsequently we will refine our understanding of the relationships between local ancestry, epigenetic and gene expression changes, and phenotype in tumor progression via integration of multi-omics datasets. Our systems genomics approach will utilize directed local regulatory networks in a Bayesian structure learning framework. RESULTS/ANTICIPATED RESULTS: Induction by EWS-FLI1 resulted in gene expression changes enriched in known ES gene sets. Higher %EUR ancestry correlated with prolonged maintenance of EWS-FLI1. We identified thousands of ancestry-linked changes to gene expression and EWS-FLI1 binding. Eighty of these genes are both differentially expressed and differentially bound based on AFR ancestry admixture level and may be some of the early critical targets that initiate the cascade of molecular changes in ES. We will identify novel drug targets, with potential cross functional use of known drugs. Once we have developed directed local regulatory networks, we will use them to test in silico potential perturbations due to small molecules or novel drugs and predict expression changes. DISCUSSION/SIGNIFICANCE: With a limited number of cell lines, we identify 80 ancestry-linked candidate loci for functional validation through genome engineering. As EWS-FLI1 itself has proven elusive to direct targeting, studying its immediate downstream effects has the potential for establishing new druggable biologic pathways for treatment of ES.

Black children have lower incidence yet worse survival than White and Latinx children with B-cell acute lymphoblastic leukemia (B-ALL). It is unclear how reported race/ethnicity (RRE) is associated with death in B-ALL after accounting for differentially expressed genes associated with genetic ancestry.Using Phase 1 and 2 NCI TARGET B-ALL cases (N = 273; RRE-Black = 21, RRE-White = 162, RRE-Latinx = 69, RRE-Other = 9, RRE-Unknown = 12), we estimated proportions of African (AFR), European (EUR), and Amerindian (AMR) genetic ancestry. We estimated hazard ratios (HR) and 95% confidence intervals (95% CI) between ancestry and death while adjusting for RRE and clinical measures. We identified genes associated with genetic ancestry and adjusted for them in RRE and death associations.Genetic ancestry varied within RRE (RRE-Black, AFR proportion: Mean: 78.5%, Range: 38.2%-93.6%; RRE-White, EUR proportion: Mean: 94%, Range: 1.6%-99.9%; RRE-Latinx, AMR proportion: Mean: 52.0%, Range: 1.2%-98.7%). We identified 10, 1, and 6 differentially expressed genes (pOur work highlights B-ALL survival differences by RRE after adjusting for ancestry differentially expressed genes suggesting other factors impacting survival are important.

There is a well-recognized male excess in childhood cancer incidence; however, it is unclear whether there is etiologic heterogeneity by sex when defined by epidemiologic risk factors. Using a 5-state registry-linkage study (cases n = 16,411; controls n = 69,816), we estimated sex-stratified odds ratios (OR) and 95% confidence intervals (95% CI) between birth and demographic characteristics for 16 pediatric cancers. Evidence of statistical interaction (p-interaction 50% of cases for all cancers, except Wilms tumor (49.6%). Sex interacted with a number of risk factors (all p-interaction

Ewing sarcoma (ES) is the second most common primary bone tumor in children and adolescents. There are few known epidemiological or genetic risk factors for ES. Numerous reports describe incidence rates and trends within the United States, but international comparisons are sparse. We used the Cancer Incidence in Five Continents (CI5) data to estimate age standardized incidence rates (ASRs; cases per million) and 95% confidence intervals (95% CIs), male-to-female incidence rate ratios (IRRs; 95% CI), and the average annual percent change in incidence (AAPC; 95% CI) for ES by geographic region for children and adults aged 0 to 49 years. We also estimated the ASR for each country or country subpopulation among the 10- to 19-year-old age range; capturing the peak incidence of ES. In total, 15 874 ES cases ages 0 to 49 were reported in the CI5 series between 1988 and 2012. AAPC estimates varied by age group and geographic region. Most of the statistically significant AAPCs showed an increased incidence over time; the only statistically significant decreases in incidence were observed among 20- to 29-year-olds and 30- to 39-year-olds in Southern Asia at -1.93% and -1.67%. When categorized by predominant ancestry, we observed countries and subpopulations with predominately African, East Asian, and Southeast Asian ancestry had the lowest incidence rates, whereas Pacific Islanders and populations with predominantly European and North African/Middle Eastern ancestry had the highest. An excess incidence in males was observed in most regions. Our results highlight substantial variation in ES incidence across geographic populations, reflecting potential ancestral influence on disease risk.

Osteosarcoma (OS) is the most common primary bone tumor in children and adolescents. The etiology of OS is largely unknown but may be informed by comparisons of incidence and trends between geographic regions. Using the Cancer Incidence in Five Continents (CI5) data from 1988 to 2012, we present OS age-standardized incidence rates (ASRs; cases/million) and average annual percent change (AAPC) and 95% confidence interval (CI) by geographic region among the age groups 0-9, 10-19, 20-29, 30-59, 60-79, 0-79. Among the 10-19 age group, we also used the most recent data (2008-2012) to present the ASRs for each country. We observed little variation in OS incidence between geographic regions in 2008-2012 across all age groups. Overall, the ASR for 0-79 ranged from 2 cases per million in Southern Asia to 4.2 in Sub-Saharan Africa. A bimodal distribution in incidence was observed with peaks in the 10-19 and 60-79 age groups across all regions over time. Overall, OS incidence was relatively stable across 1988-2012 with the only statistically significant increases in the 0-79 age group observed in Eastern Asia (AAPC: 1.8; 95% CI: 0.6, 1.9) and Sub-Saharan Africa (AAPC: 3.1; 95% CI: 0.5, 5.8). The small variation in incidence between regions and the stability in incidence over time suggests that OS carcinogenesis is not influenced by environmental or time-varying exposures.

Germline de novo mutations (DNMs) represent one of the important topics that need extensive attention from epidemiologists, geneticists, and other relevant stakeholders. Advances in next-generation sequencing technologies allowed examination of parent-offspring trios to ascertain the frequency of germline DNMs. Many epidemiological risk factors for childhood cancer are indicative of DNMs as a mechanism. The aim of this review was to give an overview of germline DNMs, their causes in general, and to discuss their relation to childhood cancer risk. In addition, we highlighted existing gaps in knowledge in many topics of germline DNMs in childhood cancer that need exploration and collaborative efforts.

Germline de novo mutations (DNMs) represent one of the important topics that need extensive attention from epidemiologists, geneticists, and other relevant stakeholders. Advances in next-generation sequencing technologies allowed examination of parent-offspring trios to ascertain the frequency of germline DNMs. Many epidemiological risk factors for childhood cancer are indicative of DNMs as a mechanism. The aim of this review was to give an overview of germline DNMs, their causes in general, and to discuss their relation to childhood cancer risk. In addition, we highlighted existing gaps in knowledge in many topics of germline DNMs in childhood cancer that need exploration and collaborative efforts.

PURPOSE To ascertain the prevalence of recurrent de novo variants among 240 pediatric patients with osteosarcoma (OS; age < 20 years) unselected for family history of cancer. METHODS The identification of de novo variants was implemented in 2 phases. In the first, we identified genes with a rare (minor allele frequency < 0.01) de novo variant in > 1 of the 95 case-parent trios examined by whole-exome sequencing (WES) who passed quality control measures. In phase 2, 145 additional patients with OS were evaluated by targeted sequencing to identify rare de novo variants in genes nominated from phase 1. Recurrent rare variants identified from phase 1 and 2 were verified as either de novo or inherited by Sanger sequencing of affected patients and their parents. Categorical and continuous data were analyzed using Fisher exact test and t tests, respectively. RESULTS Among 95 case-parent trios who underwent WES, we observed 61 de novo variants in 60 genes among 47 patients, with TP53 identified as the only gene with a pathogenic or likely pathogenic (P/LP) de novo variant in more than one case-parent trio. Among all 240 patients with OS, 13 (5.4%) harbored a P/LP TP53 germline variant, of which 6 (46.2%) were confirmed to be de novo. CONCLUSION Apart from TP53, we did not observe any other recurrent de novo P/LP variants in the case-parent trios, suggesting that new mutations in other genes are not a frequent cause of pediatric OS. That nearly half of P/LP TP53 variants in our sample were de novo suggests universal screening for germline TP53 P/LP variants among pediatric patients with OS should be considered.

The Childhood Cancer Research Network (CCRN) was established by the Children's Oncology Group (COG) as a resource for epidemiologic studies of childhood cancer. The objective of this study was to evaluate the representativeness of CCRN and identify factors associated with enrollment.The number of US childhood patients with cancer diagnosed20 years of age enrolled in CCRN (2008-2015) was compared to expected counts, calculated from Surveillance, Epidemiology, and End Results incidence rates and US Census population estimates. Observed-to-expected ratios and corresponding 95% confidence intervals (CI) were estimated across sex, race, diagnosis age, calendar year, and cancer diagnosis groups. Multivariable linear regression models were generated to evaluate the association between open COG phase 3 therapeutic trials and CCRN enrollment rates.The 43,110 cases enrolled in CCRN represented 36% of the expected childhood cancers diagnosed from 2008 to 2015 (N = 120,118). CCRN enrollment ratios [95% CI] were highest among males (0.38 [95% CI, 0.37-0.38]), non-Hispanics (0.35 [95% CI, 0.35-0.36]), and those diagnosed from 1 to 4 years of age (0.50 [95% CI, 0.50-51]). Enrollment ratios varied by diagnosis group, with leukemia, myeloproliferative diseases, myelodysplastic diseases (0.55 [95% CI, 0.54-0.55]), and renal tumors (0.55 [95% CI, 0.53-0.58]) having the highest enrollment. After adjusting for year of diagnosis and cancer diagnosis, there was a 3.1% [95% CI, 0.6-5.6%] increase in CCRN enrollment during windows of open COG therapeutic trials.Despite enrolling only 36% of newly diagnosed cases, CCRN remains a valuable resource for investigators conducting childhood cancer etiology and survivorship research. The results of this study may inform efforts to improve enrollment on current and future COG nontherapeutic registry protocols.

Increasing evidence suggests that breastfeeding may protect from childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). However, most studies have limited their analyses to any breastfeeding, and only a few data have examined exclusive breastfeeding, or other exposures such as formula milk. We performed pooled analyses and individual participant data metaanalyses of data from 16 studies (N = 17 189 controls; N = 10 782 ALL and N = 1690 AML cases) from the Childhood Leukemia International Consortium (CLIC) to characterize the associations of breastfeeding duration with ALL and AML, as well as exclusive breastfeeding duration and age at introduction to formula with ALL. In unconditional multivariable logistic regression analyses of pooled data, we observed decreased odds of ALL among children breastfed 4 to 6 months (0.88, 95% CI 0.81-0.96) or 7 to 12 months (OR 0.85, 0.79-0.92). We observed a similar inverse association between breastfeeding ≥4 months and AML (0.82, 95% CI 0.71-0.95). Odds of ALL were reduced among children exclusively breastfed 4 to 6 months (OR 0.73, 95% CI 0.63-0.85) or 7 to 12 months (OR 0.70, 95% CI 0.53-0.92). Random effects metaanalyses produced similar estimates, and findings were unchanged in sensitivity analyses adjusted for race/ethnicity or mode of delivery, restricted to children diagnosed ≥1 year of age or diagnosed with B-ALL. Our pooled analyses indicate that longer breastfeeding is associated with decreased odds of ALL and AML. Few risk factors for ALL and AML have been described, therefore our findings highlight the need to promote breastfeeding for leukemia prevention.

Leukapheresis (LA) in pediatric leukemia is performed for leukostasis, a life-threatening emergency in the setting of extremely increased blast cell counts. The authors aimed to assess the epidemiology of pediatric leukemia who received LA. The authors reviewed US nationally representative admission records of patients less than 20 years of age in the Kids' Inpatient Database for the years 2000, 2003, 2006, 2009, 2012, and 2016. Incidence of new leukemia cases who underwent LA were calculated for the years 2009, 2012, and 2016. Cox and logistic regression analyses were performed to ascertain the risk factors for adverse outcomes. There were 526 admissions for pediatric patients with acute lymphoblastic leukemia (ALL) (n=328), acute myeloid leukemia (AML) (n=124), or chronic myeloid leukemia (CML) (n=74) who underwent LA over the study period. The incidence of leukemia cases that required LA was lower in 2016 than in 2009 or 2012 (1.4%, 2.2%, and 2.7%, respectively; P=0.001). In-hospital mortality was higher in AML than ALL (hzard ratio, 3.2; 95% confidence interval, 1.1-9.1). None with CML died during admission. This first population-based study of LA in pediatric leukemia showed a decreased utilization of LA over recent years. The higher inpatient mortality in AML, as compared with ALL or CML, warrant further investigations.

Background Human phthalate exposure is widespread through contact with myriad consumer products. Exposure is particularly high through medications formulated with phthalates. Phthalates disrupt normal endocrine signaling and are associated with reproductive outcomes and incidence of some cancers. We measured associations between gestational and childhood medication-associated phthalate exposures and the incidence of childhood cancers. Methods We identified all live births in Denmark between 1997 and 2017, including both children and birth mothers. Using drug ingredient data merged with the Danish National Prescription Registry, we measured phthalate exposure through filled prescriptions for mothers during pregnancy (gestational exposure) and for children from birth until age 19 years (childhood exposure). Incident childhood cancers were ascertained from the Danish Cancer Registry, and associations were estimated with Cox regression models. Results Among 1 278 685 children, there were 2027 childhood cancer cases diagnosed over 13.1 million person–years of follow-up. Childhood phthalate exposure was strongly associated with incidence of osteosarcoma (hazard ratio [HR] = 2.78, 95% confidence interval [CI] = 1.63 to 4.75). We also observed a positive association with incidence of lymphoma (HR = 2.07, 95% CI = 1.36 to 3.14), driven by associations with Hodgkin and non-Hodgkin lymphoma but not Burkitt lymphoma. Associations were apparent only for exposure to low-molecular phthalates, which have purportedly greater biological activity. Conclusions Childhood phthalate exposure was associated with incidence of osteosarcoma and lymphoma before age 19 years. Lingering questions include which specific phthalate(s) are responsible for these associations, by what mechanisms they occur, and to what extent childhood cancer cases could be avoided by reducing or eliminating the phthalate content of medications and other consumer products.

Although global differences in the incidence of neuroblastoma have been examined, the underlying mechanism has yet to be elucidated. Previous studies have suggested genetic ancestry and human development index (HDI) as contributing factors, but few studies have been conducted at the international level. Here, we aimed to examine whether the frequency of common genomic variation associated with neuroblastoma can affect its risk at the ecological level with consideration of the HDI. Minor allele frequencies (MAFs) for 22 single-nucleotide polymorphisms (SNPs) were abstracted from the Geography of Genetic Variants Browser. The number of incident neuroblastomas for each population was obtained from the Cancer Incidence in Five Continents series. Further, population pseudo-polygenic risk scores (pp-PRSs) were calculated as a sum of MAFs at the population level, each of which was weighted by effect sizes from prior studies. Negative binomial regression was used to estimate the incidence rate ratios (IRRs) and the 95% confidence intervals (CIs) to examine whether differences in MAFs across the population influence the risk of neuroblastoma, with and without adjustment for HDI and whether pp-PRSs can be a predictor of the risk of neuroblastoma. Overall, our results indicated that the neuroblastoma risk associated with variation in SNP frequency could not be differentiated from that of HDI at the ecological level. Additionally, pp-PRSs were not significantly associated with the risk of neuroblastoma (IRR: 0.99, 95% CI: 0.62-1.60). Further study using individual-level data is warranted to minimize the bias related to the use of population-level data in this study.

Despite the vast genetic and environmental diversity in Asia, individuals of Asian and Pacific Islander (API) descent are often combined into a single group for epidemiologic analyses within the United States. We used the Surveillance, Epidemiology, and End Results (SEER) Detailed Asian/Pacific Islander Database to calculate incidence rates for discrete groups among children aged 0–19 years. Due to sample size constraints we pooled incidence among regional groups based on countries of origin: East Asians (Chinese, Japanese, Korean), Southeast (SE) Asians (Vietnamese, Laotian, Cambodian), Asian Indian/Pakistani, Oceanians (Guamanian, Samoan, Tongan), and Filipinos. Incidence rate ratios (IRR) and 95% confidence intervals (CI) were calculated comparing each API regional group to Non-Hispanic Whites (NHW) and East Asians. Lastly, we calculated the correlation between incidence of cancer in specific API ethnicities in SEER and in originating countries in the Cancer Incidence i n Five Continents. Incidence rates among API regional groups varied. Acute lymphoblastic leukemia (ALL) was lower in children of SE Asian descent (IRR 0.65, 95% CI 0.44, 0.96) compared to NHW. Acute myeloid leukemia (AML) was more common among children from Oceania compared to NHW (IRR 3.88, 95% CI 1.83, 8.22). East Asians had higher incidence rates than SE Asians but lower rates compared to children from Oceania. Correlation of some incidence rates between US-based API ethnicities and originating countries were similar. The variation observed in childhood cancer incidence patterns among API groups may indicate differences in underlying genetics and/or patterns of exposure.

Background Obesity is a risk factor for many adulthood cancers, but its role in childhood, adolescent, and young adult (AYA) cancer is unknown. Childhood and AYA acute lymphoblastic leukemia (ALL) incidence and obesity prevalence have shown concurrent increases. We sought to identify whether obesity may be a risk factor for childhood and AYA ALL. Methods Characteristics from individuals with ALL, aged 2‐30 years, diagnosed 2004‐2017 and treated on Children's Oncology Group (COG) protocols with available pre‐treatment anthropometric data (N = 4726) were compared to National Health and Nutrition Examination Survey controls (COG AALL17D2). Body mass index (BMI) was defined using standard CDC definitions. Multivariate conditional logistic regression assessed associations between BMI and ALL with additional analyses stratified by sex and race/ethnicity. Results Among cases (72% high‐risk (HR) B‐ALL, 28% T‐ALL), 5% had underweight, 58% normal weight, 17% overweight, and 20% obesity. Underweight (OR 2.11, 95% CI 1.56‐2.85) and obesity (OR 1.32, 95% CI 1.15‐1.53) were associated with B‐ALL diagnosis. Specifically, obesity was associated with B‐ALL among males (OR 1.57, 95% CI 1.30‐1.91) and Hispanic children (OR 1.78, 95% CI 1.39‐2.29). Obesity was also associated with central nervous system (CNS) involvement. Conclusion Pre‐treatment obesity is associated with HR B‐ALL among males and Hispanics, as well as with CNS involvement, suggesting common physiology between obesity and leukemogenesis. An association between underweight and ALL was confirmed, likely due to cancer‐associated wasting. These results have important public health implications for obesity prevention and treatment in children and adolescents to reduce cancer risk., Deviations in body mass index (underweight and obesity) at the time of diagnosis were significantly associated with a diagnosis of pediatric high‐risk (HR) B‐cell acute lymphoblastic leukemia (B‐ALL) compared to normal weight. Specifically, obesity was associated with HR B‐ALL in males and Hispanics. Obesity was also significantly associated with ALL central nervous system (CNS) involvement.