TelomereHunter – in silico estimation of telomere content and composition from cancer genomes

BackgroundEstablishment of telomere maintenance mechanisms is a universal step in tumor development to achieve replicative immortality. These processes leave molecular footprints in cancer genomes in the form of altered telomere content and aberrations in telomere composition. To retrieve these telomere characteristics from high-throughput sequencing data the available computational approaches need to be extended and optimized to fully exploit the information provided by large scale cancer genome data sets.ResultsWe here present TelomereHunter, a software for the detailed characterization of telomere maintenance mechanism footprints in the genome. The tool is implemented for the analysis of large cancer genome cohorts and provides a variety of diagnostic diagrams as well as machine-readable output for subsequent analysis. A novel key feature is the extraction of singleton telomere variant repeats, which improves the identification and subclassification of the alternative lengthening of telomeres phenotype. We find that whole genome sequencing-derived telomere content estimates strongly correlate with telomere qPCR measurements (r = 0.94). For the first time, we determine the correlation of in silico telomere content quantification from whole genome sequencing and whole genome bisulfite sequencing data derived from the same tumor sample (r = 0.78). An analogous comparison of whole exome sequencing data and whole genome sequencing data measured slightly lower correlation (r = 0.79). However, this is considerably improved by normalization with matched controls (r = 0.91).ConclusionsTelomereHunter provides new functionality for the analysis of the footprints of telomere maintenance mechanisms in cancer genomes. Besides whole genome sequencing, whole exome sequencing and whole genome bisulfite sequencing are suited for in silico telomere content quantification, especially if matched control samples are available. The software runs under a GPL license and is available at https://www.dkfz.de/en/applied-bioinformatics/telomerehunter/telomerehunter.html.

[1]  David T. W. Jones,et al.  Decoding the regulatory landscape of medulloblastoma using DNA methylation sequencing , 2014, Nature.

[2]  R. Wilson,et al.  Assessing telomeric DNA content in pediatric cancers using whole-genome sequencing data , 2012, Genome Biology.

[3]  Mark Hills,et al.  Telomere length measurement-caveats and a critical assessment of the available technologies and tools. , 2012, Mutation research.

[4]  J. Shay,et al.  Role of Telomeres and Telomerase in Aging and Cancer. , 2016, Cancer discovery.

[5]  Roland Eils,et al.  Integrative genomic and transcriptomic analysis of leiomyosarcoma , 2018, Nature Communications.

[6]  N. Carter,et al.  A DNA damage checkpoint response in telomere-initiated senescence , 2003, Nature.

[7]  R. Cawthon Telomere measurement by quantitative PCR. , 2002, Nucleic acids research.

[8]  J. Shay,et al.  Senescence and immortalization: role of telomeres and telomerase. , 2005, Carcinogenesis.

[9]  C B Harley,et al.  Specific association of human telomerase activity with immortal cells and cancer. , 1994, Science.

[10]  R. Reddel,et al.  Evidence for an alternative mechanism for maintaining telomere length in human tumors and tumor-derived cell lines , 1997, Nature Medicine.

[11]  Xin Hu,et al.  Systematic analysis of telomere length and somatic alterations in 31 cancer types , 2017, Nature Genetics.

[12]  N J Royle,et al.  The plasticity of human telomeres demonstrated by a hypervariable telomere repeat array that is located on some copies of 16p and 16q. , 1999, Human molecular genetics.

[13]  J. Arthur,et al.  Comparative analysis of whole genome sequencing-based telomere length measurement techniques. , 2017, Methods.

[14]  Richard Durbin,et al.  Estimating telomere length from whole genome sequence data , 2014, Nucleic acids research.

[15]  Roland Eils,et al.  Recurrent MET fusion genes represent a drug target in pediatric glioblastoma , 2016, Nature Medicine.

[16]  H. Pickett,et al.  Variant repeats are interspersed throughout the telomeres and recruit nuclear receptors in ALT cells , 2012, The Journal of cell biology.

[17]  C. Harley,et al.  Telomeres shorten during ageing of human fibroblasts , 1990, Nature.

[18]  Roland Eils,et al.  Genomic footprints of activated telomere maintenance mechanisms in cancer , 2017, bioRxiv.

[19]  Matthew J. Betts,et al.  Dissecting the genomic complexity underlying medulloblastoma , 2012, Nature.

[20]  Andy G Lynch,et al.  Telomerecat: A ploidy-agnostic method for estimating telomere length from whole genome sequencing data , 2017, Scientific Reports.

[21]  Amy Y. M. Au,et al.  DNA C-circles are specific and quantifiable markers of alternative-lengthening-of-telomeres activity , 2009, Nature Biotechnology.

[22]  Richard Durbin,et al.  Fast and accurate long-read alignment with Burrows–Wheeler transform , 2010, Bioinform..

[23]  Richard Durbin,et al.  Sequence analysis Fast and accurate short read alignment with Burrows – Wheeler transform , 2009 .

[24]  H. Pickett,et al.  Molecular characterization of inter-telomere and intra-telomere mutations in human ALT cells , 2002, Nature Genetics.

[25]  Lilit Nersisyan,et al.  Computel: Computation of Mean Telomere Length from Whole-Genome Next-Generation Sequencing Data , 2015, PloS one.

[26]  Mark Hills,et al.  Telomere extension by telomerase and ALT generates variant repeats by mechanistically distinct processes , 2013, Nucleic acids research.

[27]  Philip Thomas,et al.  A quantitative real-time PCR method for absolute telomere length. , 2008, BioTechniques.

[28]  et al.,et al.  The RNA component of human telomerase , 1995, Science.

[29]  Erdahl T. Teber,et al.  Telomere sequence content can be used to determine ALT activity in tumours , 2018, Nucleic acids research.