Project description:The human papillomavirus (HPV) genome is integrated into host DNA in most HPV-positive cancers, but the consequences for chromosomal integrity are unknown. Continuous long-read sequencing of oropharyngeal cancers and cancer cell lines identified a previously undescribed form of structural variation, "heterocateny," characterized by diverse, interrelated, and repetitive patterns of concatemerized virus and host DNA segments within a cancer. Unique breakpoints shared across structural variants facilitated stepwise reconstruction of their evolution from a common molecular ancestor. This analysis revealed that virus and virus-host concatemers are unstable and, upon insertion into and excision from chromosomes, facilitate capture, amplification, and recombination of host DNA and chromosomal rearrangements. Evidence of heterocateny was detected in extrachromosomal and intrachromosomal DNA. These findings indicate that heterocateny is driven by the dynamic, aberrant replication and recombination of an oncogenic DNA virus, thereby extending known consequences of HPV integration to include promotion of intratumoral heterogeneity and clonal evolution.SignificanceLong-read sequencing of HPV-positive cancers revealed "heterocateny," a previously unreported form of genomic structural variation characterized by heterogeneous, interrelated, and repetitive genomic rearrangements within a tumor. Heterocateny is driven by unstable concatemerized HPV genomes, which facilitate capture, rearrangement, and amplification of host DNA, and promotes intratumoral heterogeneity and clonal evolution. See related commentary by McBride and White, p. 814. This article is highlighted in the In This Issue feature, p. 799.
Project description:Human papillomavirus (HPV) integration is a critical step in cervical cancer development, while the oncogenic mechanism in genome-wide transcriptional level is still poorly understood. In this study, we employed integrative analysis on multi-omics data of cervical cancer cell lines. Through HPV integration detection, super enhancer (SE) identification, SE-associated gene expression and extrachromosomal DNA (ecDNA) investigation, we aimed to explore the genome-wide transcriptional influence of HPV integration. We identified 5 high-ranking cellular super enhancers generated by HPV integration (the HPV breakpoint induced cellular super enhancers, BP-cSE), leading to intra-chromosomal and inter-chromosomal regulations of chromosomal genes. The pathway analysis showed the dysregulated chromosomal genes were correlated to cervical cancer associated pathways. Importantly, we demonstrated that BP-cSE existed in the HPV-host ecDNA, explaining above transcription alterations. Our results suggest that HPV integration generates cellular super enhancers and functions as ecDNA to regulate unconstraint transcription, expanding the tumorigenic mechanism of HPV integration and providing insights of developing new diagnostic and therapeutic strategies.
Project description:Clonal evolution of a tumor ecosystem depends on different selection pressures that are principally immune and treatment mediated. We integrate RNA-seq, DNA sequencing, TCR-seq and SNP array data across multiple regions of liver cancer specimens to map spatio-temporal interactions between cancer and immune cells. We investigate how these interactions reflect intra-tumor heterogeneity (ITH) by correlating regional neo-epitope and viral antigen burden with the regional adaptive immune response. Regional expression of passenger mutations dominantly recruits adaptive responses as opposed to hepatitis B virus and cancer-testis antigens. We detect different clonal expansion of the adaptive immune system in distant regions of the same tumor. An ITH-based gene signature improves single-biopsy patient survival predictions and an expression survey of 38,553 single cells across 7 regions of 2 patients further reveals heterogeneity in liver cancer. These data quantify transcriptomic ITH and how the different components of the HCC ecosystem interact during cancer evolution.
Project description:Copy number analyses of regionally separated intratumoral biopsies of prostate cancers. Intratumoral heterogeneity (ITH) leads to regional biases of the mutational landscape in a single tumor and may influence the single biopsy-based clinical diagnosis and treatment decision. To evaluate the extent of ITH in unifocal prostate cancers (PCAs) that had not been sought, we analyzed multiple regional biopsies from three PCAs using DNA copy number analyses. DNA copy number showed ITH including regional biases in the presentation of a well-known driver of TMPRSS2-ERG fusion. Our analyses identified a substantial level of genetic ITH in unifocal PCAs at the genomic levels, which should be taken into account for the curation of biomarkers in the clinical setting. Four intratumoral biopsies were obtained per tumor for three prostate cancers. Radical prostatectomy tissue from three patients with prostate cancers were obtained. Board-certified pathologists reviewed the hematoxylin&eosin stained sections and identified tumor-rich regions (> 80% purity). We selected four different areas for biopsy that were at least 5mm apart and were comprised of the most common Gleason pattern (the most common histologic patterns with minimal histologic differences). Copy number profiling was performed using Agilent 180K platform according to the manufacturer's protocol.
Project description:Multiple HPV genotypes infection is frequently detected in HPV+ cervical lesions, however it is not well stablished how is the different viral interaction during the carcinogenic process. Here we carried out a comprehensive study to characterize the multiple HPV genome expression and integration by RNA-Seq analysis in 19 invasive cervical carcinomas with HPV coinfections. Analysis of tumoral DNA by a hybridization kit indicated multi-infection ranging from 2 to 6 different HPV genotypes, without a preferential species coinfection. The expression analysis showed that a single HPV genotype preferentially expressed its genome, might indicating a competition between the infecting virus. Finally, the search for HPV/human chimeric transcripts indicated integration from just one HPV in almost all samples, corroborating the expression findings.
Project description:Esophageal squamous cell carcinoma (ESCC) is among the most common malignancies, but little is known about its spatial intratumoral heterogeneity (ITH) and temporal clonal evolutionary processes. To address this, we performed multiregion whole-exome sequencing on 51 tumor regions from 13 ESCC cases and multiregion global methylation profiling for 3 of these 13 cases. We found an average of 35.8% heterogeneous somatic mutations with strong evidence of ITH. Half of the driver mutations located on the branches of tumor phylogenetic trees targeted oncogenes, including PIK3CA, NFE2L2 and MTOR, among others. By contrast, the majority of truncal and clonal driver mutations occurred in tumor-suppressor genes, including TP53, KMT2D and ZNF750, among others. Interestingly, phyloepigenetic trees robustly recapitulated the topological structures of the phylogenetic trees, indicating a possible relationship between genetic and epigenetic alterations. Our integrated investigations of spatial ITH and clonal evolution provide an important molecular foundation for enhanced understanding of tumorigenesis and progression in ESCC.
Project description:The aim of this study was to investigate the effect of VEGF targeted therapy (sunitinib) on intratumoral heterogeneity (ITH) in metastatic clear cell renal cancer (mRCC). 138 samples from patients with clear cell renal cell carcinoma, including biological replicates of nephrectomy samples. RNA extracted fresh frozen tissue samples.