Project description:Long non-coding RNAs (lncRNAs) play an important role in gene regulation and contribute to tumorigenesis. While pan-cancer studies of lncRNA expression have been performed for adult malignancies, the lncRNA landscape across pediatric cancers remains largely uncharted. Here, we curated RNA sequencing data for 1,044 pediatric leukemia and extra-cranial solid tumors and integrated paired tumor whole genome sequencing and epigenetic data in relevant cell line models to explore lncRNA expression, regulation, and association with cancer. A total of 2,657 lncRNAs were robustly expressed across six pediatric cancers, including 1,142 exhibiting histotype-elevated expression. DNA copy number alterations contributed to lncRNA dysregulation at a proportion comparable to protein coding genes. Application of a multi-dimensional framework to identify and prioritize lncRNAs impacting gene networks revealed that lncRNAs dysregulated in pediatric cancer are associated with proliferation, metabolism, and DNA damage hallmarks. Analysis of upstream regulation via cell-type specific transcription factors further implicated distinct histotype-elevated and developmental lncRNAs. Integration of these analyses prioritized lncRNAs for experimental validation, and silencing of TBX2-AS1, the top-prioritized neuroblastoma-specific lncRNA, resulted in significant growth inhibition of neuroblastoma cells, confirming the computational predictions. Taken together, these data provide a comprehensive characterization of lncRNA regulation and function in pediatric cancers and pave the way for future mechanistic studies.
Project description:This study aims to compared ctDNA methylation status induced by ionizing to different ograns. SD rats were irradiated with local radaition to brain, lung or skin. Serum was collected and subjiected to ctDNA extraction. ctDNA were then treated by methylation-sensive bisulfite and sequencing.
Project description:For identification of candidate genes that is specifically expressed in Ewing family tumor (EFT) cells, we performed DNA microarray-based global expression profiling using Affymetrix Human Genome U133 Plus 2.0 Array and analyxed expression profiles from EFT cell lines (7 lines), neuroblastoma (NB) cell lines (3 lines), a Rhabdomyosarcoma (RMS) cell line, and a human immortalized mesenchymal progenitor cells UET-13 cells. Experiment Overall Design: Expression profiles of pediatric solid tumor cell lines were analyzed and compared using Affymetrix HG-U133 Plus 2.0 (GPL570).
Project description:In this study, we performed systematic characterization of chromoplexy, chromothripsis and extrachromosomal DNA across five types of pediatric solid tumors: neuroblastoma, Ewing sarcoma, Wilms tumor, hepatoblastoma and rhabdomyosarcoma. Almost half of all tumors had at least one complex SV and we identified candidate pathogenic events that affect genes or chromosomal alterations known to be relevant in these cancer types. In conclusion, complex SVs are prevalent and highly pathogenic in pediatric solid tumors.
Project description:Pediatric solid tumors arise from endodermal, ectodermal, or mesodermal lineages. Although the overall survival of children with solid tumors is 75%-80%, that of children with recurrent disease is below 30%. To capture the complexity and diversity of pediatric solid tumors and establish new models of recurrent disease, we developed a protocol to produce orthotopic patient-derived xenografts (O-PDXs) at diagnosis, recurrence, and autopsy. Tumor specimens were received from 168 patients, and 64 O-PDXs were established for 12 types of pediatric solid tumors. The origins of the O-PDX tumors were reflected in their gene-expression profiles and epigenomes. Genomic profiling of the tumors, including detailed clonal analysis, was performed to determine whether the clonal population in the xenograft recapitulated the patientÂ’s tumor. We identified several drug vulnerabilities and showed that the combination of a WEE1 inhibitor (AZD1775), irinotecan, and vincristine can lead to complete response in multiple rhabdomyosarcoma O-PDX tumors in vivo.
Project description:Christopher Abbosh and Charles Swanton discuss circulating tumor DNA as a potential biomarker for neoadjuvant treatment response in solid tumors.
Project description:Aggresome is a para nuclear inclusion body that functions as a storage compartment for misfolded proteins. Our previous work revealed the presence of aggresomes in pediatric choroid plexus tumors (CPT). CPTs are rare neoplasms comprised of three pathological subgroups; choroid plexus carcinoma (CPC), a grade III tumor, atypical choroid plexus papilloma (ACPP), a grade II tumor, and choroid plexus papilloma (CPP), a grade I tumor. In the current study, we aimed to investigate the prognostic value of aggresomes-positivity and its correlation to the pathological and molecular subtypes. The proteomics profiling of 21 CPT pediatric samples was investigated using ABSciex Triple TOF 5600+ mass spectrometer.
Project description:To develop diagnostic and prognostic biomarkers, we compared methylation profiles of HCC tissues and normal blood by analyzing 485,000 CpG markers and identified a HCC enriched methylation marker panel compared to that of normal blood. We found there was a highly correlation of methylation profiles between DNA from HCC cancer tissue and matched plasma ctDNA within the same patient. We then selected 10 markers from this panel and created a combined diagnosis score (cd-score) which showed high diagnostic specificity and sensitivity in both a training cohort and an independent validation cohort. We also showed the cd-score correlate highly with tumor load, treatment response and stage and is superior to that by AFP. We also showed the cd-score correlate highly with tumor load, treatment response and stage and is superior to that by AFP. Additional, we generated 8 markers from unicox and LASSO-cox analysis and created a combined prognosis score (cp-score) which could predict prognosis and survival. Together, these findings demonstrated the utility of ctDNA methylation markers in the diagnosis, treatment evaluation and prognosis of HCC.