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1.
PLoS Pathog ; 17(8): e1009875, 2021 08.
Article in English | MEDLINE | ID: mdl-34432858

ABSTRACT

Development of cervical cancer is directly associated with integration of human papillomavirus (HPV) genomes into host chromosomes and subsequent modulation of HPV oncogene expression, which correlates with multi-layered epigenetic changes at the integrated HPV genomes. However, the process of integration itself and dysregulation of host gene expression at sites of integration in our model of HPV16 integrant clone natural selection has remained enigmatic. We now show, using a state-of-the-art 'HPV integrated site capture' (HISC) technique, that integration likely occurs through microhomology-mediated repair (MHMR) mechanisms via either a direct process, resulting in host sequence deletion (in our case, partially homozygously) or via a 'looping' mechanism by which flanking host regions become amplified. Furthermore, using our 'HPV16-specific Region Capture Hi-C' technique, we have determined that chromatin interactions between the integrated virus genome and host chromosomes, both at short- (<500 kbp) and long-range (>500 kbp), appear to drive local host gene dysregulation through the disruption of host:host interactions within (but not exceeding) host structures known as topologically associating domains (TADs). This mechanism of HPV-induced host gene expression modulation indicates that integration of virus genomes near to or within a 'cancer-causing gene' is not essential to influence their expression and that these modifications to genome interactions could have a major role in selection of HPV integrants at the early stage of cervical neoplastic progression.


Subject(s)
Carcinogenesis/pathology , Chromatin/metabolism , Genome, Viral , Human papillomavirus 16/isolation & purification , Papillomavirus Infections/complications , Uterine Cervical Neoplasms/pathology , Virus Integration , Carcinogenesis/metabolism , Chromatin/genetics , Epigenesis, Genetic , Female , Humans , Tumor Cells, Cultured , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/metabolism , Uterine Cervical Neoplasms/virology
2.
Blood ; 136(14): 1657-1669, 2020 10 01.
Article in English | MEDLINE | ID: mdl-32573700

ABSTRACT

Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.


Subject(s)
Antineoplastic Agents/pharmacology , Crizotinib/pharmacology , Drug Resistance, Neoplasm/genetics , Interleukin-10 Receptor alpha Subunit/genetics , Lymphoma, Large-Cell, Anaplastic/genetics , Protein Kinase Inhibitors/pharmacology , Protein-Tyrosine Kinases/genetics , Antineoplastic Agents/therapeutic use , CRISPR-Cas Systems , Cell Line , Crizotinib/therapeutic use , Dose-Response Relationship, Drug , Gene Editing , Gene Expression , Humans , Immunohistochemistry , Interleukin-10 Receptor alpha Subunit/metabolism , Lymphoma, Large-Cell, Anaplastic/drug therapy , Lymphoma, Large-Cell, Anaplastic/metabolism , Lymphoma, Large-Cell, Anaplastic/pathology , Models, Biological , Nucleophosmin , Protein Kinase Inhibitors/therapeutic use , Protein-Tyrosine Kinases/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction/drug effects
3.
EMBO Rep ; 18(7): 1231-1247, 2017 07.
Article in English | MEDLINE | ID: mdl-28500258

ABSTRACT

Spermatogenesis is associated with major and unique changes to chromosomes and chromatin. Here, we sought to understand the impact of these changes on spermatogenic transcriptomes. We show that long terminal repeats (LTRs) of specific mouse endogenous retroviruses (ERVs) drive the expression of many long non-coding transcripts (lncRNA). This process occurs post-mitotically predominantly in spermatocytes and round spermatids. We demonstrate that this transposon-driven lncRNA expression is a conserved feature of vertebrate spermatogenesis. We propose that transposon promoters are a mechanism by which the genome can explore novel transcriptional substrates, increasing evolutionary plasticity and allowing for the genesis of novel coding and non-coding genes. Accordingly, we show that a small fraction of these novel ERV-driven transcripts encode short open reading frames that produce detectable peptides. Finally, we find that distinct ERV elements from the same subfamilies act as differentially activated promoters in a tissue-specific context. In summary, we demonstrate that LTRs can act as tissue-specific promoters and contribute to post-mitotic spermatogenic transcriptome diversity.


Subject(s)
DNA Transposable Elements , Evolution, Molecular , Spermatogenesis , Transcription, Genetic , Animals , Endogenous Retroviruses/genetics , Genomics , Male , Mice , Open Reading Frames , Promoter Regions, Genetic , RNA, Long Noncoding/genetics , Spermatocytes/physiology , Terminal Repeat Sequences , Transcriptome
4.
Nat Biotechnol ; 41(10): 1457-1464, 2023 Oct.
Article in English | MEDLINE | ID: mdl-36747096

ABSTRACT

DNA comprises molecular information stored in genetic and epigenetic bases, both of which are vital to our understanding of biology. Most DNA sequencing approaches address either genetics or epigenetics and thus capture incomplete information. Methods widely used to detect epigenetic DNA bases fail to capture common C-to-T mutations or distinguish 5-methylcytosine from 5-hydroxymethylcytosine. We present a single base-resolution sequencing methodology that sequences complete genetics and the two most common cytosine modifications in a single workflow. DNA is copied and bases are enzymatically converted. Coupled decoding of bases across the original and copy strand provides a phased digital readout. Methods are demonstrated on human genomic DNA and cell-free DNA from a blood sample of a patient with cancer. The approach is accurate, requires low DNA input and has a simple workflow and analysis pipeline. Simultaneous, phased reading of genetic and epigenetic bases provides a more complete picture of the information stored in genomes and has applications throughout biomedicine.

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