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Herein we evaluated a series of 21 embryonal rhabdomyosarcomas of the uterine corpus (ucERMS), a rare neoplasm, to characterize their morphology, genomics, and behavior. Patients ranged from 27 to 73 (median 52) years and tumors from 4 to 15 (median 9) cm, with extrauterine disease noted in two. Follow-up (median 16 months) was available for 14/21 patients; nine were alive and well, four died of disease, and one died from other causes. Most tumors (16/21) showed predominantly classic morphology, comprised of alternating hyper- and hypocellular areas of primitive small cells and differentiating rhabdomyoblasts in a loose myxoid/edematous stroma. A cambium layer was noted in all; seven had heterologous elements (six with fetal-type cartilage) and eight displayed focal anaplasia. The remaining five neoplasms showed only a minor component (

Pediatric tumors are uncommon, yet are the leading cause of cancer-related death in childhood. Tumor types, molecular characteristics, and pathogenesis are unique, often originating from a single genetic driver event. The specific diagnostic challenges of childhood tumors led to the development of the first World Health Organization (WHO) Classification of Pediatric Tumors. The classification is rooted in a multilayered approach, incorporating morphology, IHC, and molecular characteristics. The volume is organized according to organ sites and provides a single, state-of-the-art compendium of pediatric tumor types. A special emphasis was placed on “blastomas,” which variably recapitulate the morphologic maturation of organs from which they originate. Significance: In this review, we briefly summarize the main features and updates of each chapter of the inaugural WHO Classification of Pediatric Tumors, including its rapid transition from a mostly microscopic into a molecularly driven classification systematically taking recent discoveries in pediatric tumor genomics into account.

Spina bifida has been reported to co-occur with pediatric cancer, but comprehensive evaluations remained elusive. We investigated this co-occurrence in two large, population-based studies in Taiwan (N = 1900 cancer cases, 2,077,137 controls) and Denmark (N = 5508 cases, 137,700 controls). Analyses in Denmark were restricted to the period before prenatal diagnostics became available (2004) and pregnancy terminations of fetuses with birth defects became more common. Using national patient and cancer registries, we linked spina bifida and cancer diagnoses among cases and non-cases. The risk of spina bifida among all cancer cases was increased and similar in Denmark [odds ratio (OR)=8.4, 95% confidence interval (CI) 5.1-13.8] and Taiwan (OR = 8.5, 95% CI 4.0-17.8), particularly for central nervous system (CNS) tumors (Denmark: OR = 16.3, 95% CI 8.1-33.0; Taiwan: OR = 26.6, 95% CI 8.5, 83.1), including benign CNS tumors (Denmark: OR = 41.5, 95% CI 21.2, 81.4). These findings suggest the need for comprehensive investigation of shared risk factors in the link between spina bifida and pediatric cancer.

Background: Though the association between parental age at child's birth and the risk of childhood cancer has been previously investigated, the evidence to date is inconclusive and scarce for rarer cancer types.Methods: Cancer cases (N = 5,856) were selected from all children born from 1968 to 2014 and diagnosed from 1968 to 2015 in Denmark at less than 16 years of age listed in the nationwide Danish Cancer Registry. Cases were individually matched to controls (1: 100) on sex and year of birth with a total of 585,594 controls randomly sampled from all live births in Denmark from the Danish Central Population Registry. Parental age at child's birth was extracted from the Central Population Registry. Conditional logistic regression models were used to estimate odds ratios for the association between parental age at child's birth and childhood cancer risk. Parental age was modeled as both categorical (referent group, parents aged 25-29) and continuous per 5-year increase in age.Results: Offspring of older mothers were at an increased risk of acute lymphoblastic leukemia [OR = 1.10, 95% CI: (1.02, 1.19) per 5-year increase in age]. Older maternal age (40+) increased the risk of non-Hodgkin lymphoma [OR = 1.96, 95%CI: (1.12, 3.43)]. The risk of Wilms' tumor also appeared elevated with older paternal age [OR = 1.11, 95% CI: (0.97, 1.28) per 5-year increment in age].Conclusion: Older parental age was a risk factor for various childhood cancers in Danish children. Further investigation of the biological and social factors that may be contributing to these associations is warranted. (C) 2017 Elsevier Ltd. All rights reserved.

Summary: The discovery of cancer-associated alterations has primarily focused on genetic variants. Nonetheless, altered epigenomes contribute to deregulate transcription and promote oncogenic pathways. Here, we designed an algorithmic approach (RESET) to identify aberrant DNA methylation and associated cis-transcriptional changes across >6,000 human tumors. Tumors exhibiting mutations of chromatin remodeling factors and Wnt signaling displayed DNA methylation instability, characterized by numerous hyper- and hypo-methylated loci. Most silenced and enhanced genes coalesced in specific pathways including apoptosis, DNA repair, and cell metabolism. Cancer-germline antigens (CG) were frequently epigenomically enhanced and their expression correlated with response to anti-PD-1, but not anti-CTLA4, in skin melanoma. Finally, we demonstrated the potential of our approach to explore DNA methylation changes in pediatric tumors, which frequently lack genetic drivers and exhibit epigenomic modifications. Our results provide a pan-cancer map of aberrant DNA methylation to inform functional and therapeutic studies. : Saghafinia et al. present an algorithmic approach to identify cancer-associated DNA methylation changes affecting gene expression. By analyzing >6,000 adult and pediatric tumors, the authors identify numerous DNA methylation changes at gene promoters that coalesce into a few pathways and that were associated with patient prognosis and response to therapy. Keywords: aberrant DNA methylation, cancer epigenetics, DNA methylation instability, TCGA pan-cancer cohort, pediatric cancer

In the present study, we evaluated whether infection of microvascular endothelial cells (HMECs) with HHV-8 can trigger the expression of PAX2 oncogene and whether PAX2 protein is involved in HHV-8–induced transformation of HMECs. We found that HHV-8 infection induced the expression of both the PAX2 gene and PAX2 protein in HMECs but failed to induce PAX2 protein in HMECs stably transfected with PAX2 antisense (HMEC-AS). HHV-8–infected HMECs but not HMEC-AS acquired proinvasive proadhesive properties, enhanced survival and in vitro angiogenesis, suggesting a correlation between PAX2 expression and the effects triggered by HHV-8 infection. When HMEC-expressing PAX2 by stable transfection with PAX2 sense gene or by HHV-8 infection were implanted in vivo in severe combined immunodeficient (SCID) mice, enhanced angiogenesis and proliferative lesions resembling KS were observed. HHV-8–infected HMEC-AS failed to induce angiogenesis and KS-like lesions. These results suggest that the expression of PAX2 is required for the proangiogenic and proinvasive changes induced by HHV-8 infection in HMECs. In conclusion, HHV-8 infection may activate an embryonic angiogenic program in HMECs by inducing the expression of PAX2 oncogene.

Karyotypical alteration of chromosome 5 and in particular band 5q13 is a frequent finding in hairy cell leukemia (HCL). We have previously identified a number of candidate genes localized in close proximity to a constitutional inv(5)(p13.1q13.3) breakpoint in one HCL patient. These included beta-hexosaminodase HEXB, frequently mutated in the lysosomal storage disorder Sandhoff disease. We now report that the 5q13.3 breakpoint disrupts a novel evolutionary conserved alternative isoform of HEXB. This isoform directly overlaps, in a cis-antisense fashion, exon 1 of the gene for ectodermal neuronal cortex 1 ENC-1, and was thus named ENC-1AS. ENC-1 has previously been shown to be overexpressed in several malignancies, and is believed to play a critical regulatory role in malignant transformation of various tumors. Importantly, subsequent analysis of ENC-1 in purified primary HCL tumor cells revealed a striking upregulation of ENC-1 in all 26 patients examined, compared with normal peripheral blood lymphocytes from healthy donors. Upon further analysis of the ENC-1/ENC-1AS locus, we identified a complex 5' regulatory mechanism involving an inverse expression of the ENC-1 sense and the ENC-1AS transcripts in several tissues supporting the hypothesis that expression of ENC-1AS regulates ENC-1 levels. In addition, we have also found tissue-specific methylation of a 1.2 kb segment encompassing the overlapping ENC-1/ENC-1AS 5' exons, adding to the complexity of the regulation of this locus. Altogether, these results suggest that upregulation of ENC-1 contributes to the development of HCL and provides new information on the possible dysregulation of ENC-1 including expression of a novel antisense gene, ENC-1AS.

WT1, a critical regulator of kidney development, is a tumor suppressor for nephroblastoma but in some contexts functions as an oncogene. A limited number of direct transcriptional targets of WT1 have been identified to explain its complex roles in tumorigenesis and organogenesis. In this study we performed genome-wide screening for direct WT1 targets, using a combination of ChIP–ChIP and expression arrays. Promoter regions bound by WT1 were highly G-rich and resembled the sites for a number of other widely expressed transcription factors such as SP1, MAZ, and ZNF219. Genes directly regulated by WT1 were implicated in MAPK signaling, axon guidance, and Wnt pathways. Among directly bound and regulated genes by WT1, nine were identified in the Wnt signaling pathway, suggesting that WT1 modulates a subset of Wnt components and responsive genes by direct binding. To prove the biological importance of the interplay between WT1 and Wnt signaling, we showed that WT1 blocked the ability of Wnt8 to induce a secondary body axis during Xenopus embryonic development. WT1 inhibited TCF-mediated transcription activated by Wnt ligand, wild type and mutant, stabilized β-catenin by preventing TCF4 loading onto a promoter. This was neither due to direct binding of WT1 to the TCF binding site nor to interaction between WT1 and TCF4, but by competition of WT1 and TCF4 for CBP. WT1 interference with Wnt signaling represents an important mode of its action relevant to the suppression of tumor growth and guidance of development.

Evaluation of transcriptional changes in the striatum may be an effective approach to understanding the natural history of changes in expression contributing to the pathogenesis of Huntington disease (HD). We have performed genome-wide expression profiling of the YAC128 transgenic mouse model of HD at 12 and 24 months of age using two platforms in parallel: Affymetrix and Illumina. The data from these two powerful platforms were integrated to create a combined rank list, thereby revealing the identity of additional genes that proved to be differentially expressed between YAC128 and control mice. Using this approach, we identified 13 genes to be differentially expressed between YAC128 and controls which were validated by quantitative real-time PCR in independent cohorts of animals. In addition, we analyzed additional time points relevant to disease pathology: 3, 6 and 9 months of age. Here we present data showing the evolution of changes in the expression of selected genes: Wt1, Pcdh20 and Actn2 RNA levels change as early as 3 months of age, whereas Gsg1l, Sfmbt2, Acy3, Polr2a and Ppp1r9a RNA expression levels are affected later, at 12 and 24 months of age. We also analyzed the expression of these 13 genes in human HD and control brain, thereby revealing changes in SLC45A3, PCDH20, ACTN2, DDAH1 and PPP1R9A RNA expression. Further study of these genes may unravel novel pathways contributing to HD pathogenesis. DDBJ/EMBL/GenBank accession no: GSE19677.