Weischenfeldt Group
We combine computational and experimental approaches to understand how cancers evolve. We study the mutational processes and clonal evolution trajectories that shape tumour genomes, and how these changes drive metastasis and treatment resistance.Working with clinicians and research partners in Denmark and internationally, we aim to turn our findings into biomarkers that identify patients with aggressive disease and guide personalised treatment.
Cancer is a disease of the genome, fuelled by the accumulation of genomic alterations that improve the fitness of the cell. Our overarching goal is to understand how tumour cells escape and evolve in time and space to cause metastatic, treatment-resistant disease – and to use this knowledge to improve risk stratification and treatment selection for patients.
We combine computational cancer genomics, whole-genome sequencing of large patient cohorts, and single-cell and spatial technologies to address the following questions:
- Which mutational processes shape cancer genomes, and can their “fingerprints” predict which tumours will become aggressive?
- How do complex structural variants, extrachromosomal DNA (ecDNA) and changes to the 3D genome activate oncogenes and inactivate tumour suppressor genes?
- How do genetic and epigenetic “second hits” inactivate tumour suppressor genes that are missed by conventional analyses?
- How do clonal evolution and cellular plasticity interact to drive metastatic dissemination and therapy resistance?
- How can genome-informed biomarkers be brought into the clinic to tailor treatment to the individual patient?
ntegrated mutational footprints and genomic drivers define aggressive prostate cancer
In the largest whole-genome study of prostate cancer to date (Pan Prostate Cancer Group, ~1,000 patients), we integrated substitution, insertion–deletion, copy-number and complex structural variant signatures and identified eight integrated mutational footprints (IMFs) that explain the mutational processes in 85% of primary prostate cancers. Four footprints, present in 37% of tumours, were associated with shorter time to metastasis, and the footprints predicted response to androgen receptor pathway inhibitors. A companion study mapped the full spectrum of driver alterations, found at least one recurrent alteration in 97% of tumours and defined four genomic “oncotypes”, two of which carry a poor prognosis.
- Gruber, Olsen, Hernando, Cheng et al., Nature, 2026 (PMID: 42717097)
- Pellegrina, Kiriy, Cheng et al., Nature Communications, 2026 (PMID: 42888190)
- Gerhäuser et al., Cancer Cell, 2018 (PMID: 30537516)
- Weischenfeldt et al., Cancer Cell, 2013 (PMID: 23410972)
Clonal evolution and cellular plasticity drive metastasis and treatment resistance
Using whole-genome and single-nucleus RNA sequencing of spatially distinct tumour samples, we showed that prostate cancer metastasises through both single-clone and multi-clone seeding, that the primary tumour continues to evolve after metastatic spread, and that metastatic seeding converges on androgen receptor-independent transcriptional states. In glioblastoma, we developed methods to resolve ecDNA at single-cell resolution, showing that rare ecDNA-carrying clones can expand to dominate relapse, and showed that immunotherapy drives a shift towards mesenchymal tumour cell states.
- Mikutenaite, Karadoulama et al., Nature Communications, 2025 (PMID: 41436444)
- Hendriksen et al., Genome Biology, 2026 (PMID: 41606654)
- Hendriksen et al., Neuro-Oncology, 2024 (PMID: 38695342)
- Gerhäuser et al., Cancer Cell, 2018 (PMID: 30537516)
New mechanisms of tumour suppressor gene inactivation
We developed Epi2Hit, which combines whole genomes, epigenomes and gene expression to detect biallelic inactivation through DNA methylation of one allele and loss of the other. Applied to more than a thousand cancers, this revealed epigenetic inactivation of ZFHX3 at a frequency similar to TP53, linked to MYC activation and shorter time to metastasis. An enzyme family-centred pan-cancer analysis identified helicases as frequently mutated cancer genes and hemizygous loss as a common tumour suppression mechanism.
- Kiriy et al., Nature Communications, 2026 (PMID: 42716948)
- Voßgröne, Favero et al., Science Advances, 2026 (PMID: 41719398)
- Flynn et al., Molecular Systems Biology, 2024 (PMID: 39026103)
- Tulstrup et al., Nature Communications, 2021 (PMID: 34663818)
Structural variants, the 3D genome and enhancer hijacking
We have shown how structural variants are guided by, and in turn reshape, the 3D organisation of the genome, and how they activate oncogenes through enhancer hijacking – including SV-mediated hijacking of onco-enhancers in cancer and, beyond cancer, a non-coding enhancer variant that causes an inherited cardiac syndrome.
- Pellegrina, Kiriy, Cheng et al., Nature Communications, 2026 (PMID: 42888190)
- Dubois, Sidiropoulos et al., Nature Reviews Cancer, 2022 (PMID: 35764888)
- Sidiropoulos et al., Genome Research, 2022 (PMID: 35177558)
- Christensen et al., European Heart Journal, 2025 (PMID: 40208226)
- Li et al., Nature, 2020 (PMID: 32025012)
- Rheinbay et al., Nature, 2020 (PMID: 32025015)
- Weischenfeldt et al., Nature Genetics, 2017 (PMID: 27869826)
Mutational processes and genomic biomarkers for risk stratification in prostate cancer
- We use whole-genome sequencing and machine learning to define mutational processes, driver alterations and genomic subtypes, and to develop biomarkers that distinguish indolent from aggressive disease and predict treatment response.
Clonal evolution, plasticity and metastatic dissemination
- We reconstruct the clonal evolution of tumours from multi-region, single-cell and spatial data to understand how clonal dynamics, transcriptional plasticity and the tumour microenvironment interact to drive metastasis and treatment resistance in prostate cancer and glioblastoma.
Complex structural variants, ecDNA and the 3D genome
- We study how complex structural variants and extrachromosomal DNA emerge, how they alter chromatin looping and gene regulation (e.g. enhancer hijacking), and how they contribute to oncogene amplification and tumour heterogeneity. We integrate somatic alterations with epigenetic data and chromatin conformation methods such as Hi-C.
Epigenetic and genetic second hits in tumour suppressor genes
- We develop integrative computational methods to identify tumour suppressor genes inactivated by combinations of genomic loss, DNA methylation and other mechanisms that escape standard mutation-based analyses.
We develop and apply computational and molecular biology approaches. We have optimised and integrated a broad range of sequencing technologies on clinical material, including whole-genome sequencing, RNA-seq, ATAC-seq, Hi-C and Capture-Hi-C, DNA methylation profiling, targeted panel sequencing, single-cell and single-nucleus RNA-seq, single-cell multiome, spatial transcriptomics and long-read sequencing.
We develop open computational methods – for example for integrated mutational signatures, biallelic epigenetic inactivation (Epi2Hit) and single-cell ecDNA detection (ecSingle) – and apply machine learning to large cancer genome cohorts. Analyses run on high-performance computing systems; we use Git for version control and containers (Docker) for portable, reproducible pipelines. Code is shared on GitHub.
Selected publications
# = joint corresponding/last author; * = joint first author
- Integrated signatures define mutational processes in prostate cancer. Gruber AJ*, Olsen AV*, Hernando B*, Cheng KCL*, …, Macintyre G#, Reimand J#, Weischenfeldt J#. Nature, 2026. DOI: 1038/s41586-026-10468-w. PMID: 42717097
- The molecular heterogeneity and clinical impact of genomic driver alterations in prostate cancer. Pellegrina D*, Kiriy D*, Cheng KCL*, …, Wedge DC, Weischenfeldt J#, Reimand J#. Nature Communications, 2026. DOI: 1038/s41467-026-77900-7. PMID: 42888190
- Recurrent mechanisms of biallelic epigenetic inactivation reveal new putative tumour suppressor genes in prostate cancer. Kiriy D, Favero F, Gerhäuser C, …, Schlomm T, Reimand J, Weischenfeldt J#. Nature Communications, 2026. DOI: 1038/s41467-026-72182-5. PMID: 42716948
- Resolving clonal evolution and selection of extrachromosomal DNA at single-cell resolution. Hendriksen JD, Locallo A, Schlotmann BC, …, Lassen U, Weischenfeldt J#. Genome Biology, 2026. DOI: 1186/s13059-026-03933-2. PMID: 41606654
- Hemizygous loss of helicases promotes genomic instability and cancer development. Voßgröne K*, Favero F*, Kashyap K, …, Mardin BR, Weischenfeldt J#, Sørensen CS#. Science Advances, 2026. DOI: 1126/sciadv.adv4540. PMID: 41719398
- Clonal evolution and transcriptional plasticity shape metastatic dissemination routes in prostate cancer. Mikutenaite M*, Karadoulama E*, Favero F, …, Minner S, Schlomm T, Weischenfeldt J#. Nature Communications, 2025. DOI: 1038/s41467-025-66704-w. PMID: 41436444
- Somatic CpG hypermutation is associated with mismatch repair deficiency in cancer. Flynn A, Waszak SM, Weischenfeldt J#. Molecular Systems Biology, 2024. DOI: 1038/s44320-024-00054-5. PMID: 39026103
- Immunotherapy drives mesenchymal tumor cell state shift and TME immune response in glioblastoma patients. Hendriksen JD, Locallo A, Maarup S, …, Lassen U, Weischenfeldt J#. Neuro-Oncology, 2024. DOI: 1093/neuonc/noae085. PMID: 38695342
- Structural variations in cancer and the 3D genome. Dubois F, Sidiropoulos N, Weischenfeldt J#, Beroukhim R#. Nature Reviews Cancer, 2022. DOI: 1038/s41568-022-00488-9. PMID: 35764888
- Somatic structural variant formation is guided by and influences genome architecture. Sidiropoulos N, Mardin BR, Rodríguez-González FG, …, Aiden EL, Weischenfeldt J#. Genome Research, 2022. DOI: 1101/gr.275790.121. PMID: 35177558
- Patterns of somatic structural variation in human cancer genomes. Li Y, Roberts ND, Wala JA, …, Weischenfeldt J#, Beroukhim R#, Campbell PJ#. Nature, 2020. DOI: 1038/s41586-019-1913-9. PMID: 32025012
- Analyses of non-coding somatic drivers in 2,658 cancer whole genomes. Rheinbay E, Nielsen MM, Abascal F, …, Weischenfeldt J#, Beroukhim R#, Martincorena I#, Pedersen JS#, Getz G#. Nature, 2020. DOI: 1038/s41586-020-1965-x. PMID: 32025015
- Molecular evolution of early-onset prostate cancer identifies molecular risk markers and clinical trajectories. Gerhäuser C, Favero F, Risch T, …, Schlomm T, Weischenfeldt J#. Cancer Cell, 2018. DOI: 1016/j.ccell.2018.10.016. PMID: 30537516
- Pan-cancer analysis of somatic copy-number alterations implicates IRS4 and IGF2 in enhancer hijacking. Weischenfeldt J*, Dubash T, Drainas AP, …, Glimm H, Korbel JO. Nature Genetics, 2017. DOI: 1038/ng.3722. PMID: 27869826
Selected news & media
2026
University of Copenhagen News: Researchers identify genetic clues that could reveal aggressive prostate cancer
EurekAlert: Genomic cancer driver study reveals new clues to why some prostate cancers become aggressive. On the Nature Communications driver study
Videnskab.dk: Danske forskere i spidsen for opsigtsvækkende nyt studie om prostatakræft. In Danish, with independent comment from a consultant urologist
2024
UCPH Faculty of Health: Now we know why successful treatment does not affect specific cancer cells. Plus a Neuro-Oncology podcast interview
Neuro-Oncology podcast: Immunotherapy drives mesenchymal shift in GBM
2020
University of Copenhagen: Global study maps cancer mutations in large catalogue
Videnskab.dk: Stort kræft-forskningsprojekt kortlægger uudforsket del af vores DNA
Follow Joachim Weischenfeldt on LinkedIn | on BlueSky
Collaborative research programmes
Pan Prostate Cancer Group (PPCG) – international prostate cancer consortium
Department of Urology, Charité-Universitätsmedizin Berlin
Independent Research Fund Denmark
National Institutes of Health
Rigshospitalet
Carlsbergfondet
Arvid Nielsson
Danish Cancer Society
NEYE Fonden
Sygeforsikringen danmark
Kirsten og Freddy Johansens Fond
The laboratory has been awarded the LEAF - Laboratory Efficiency Assessment Framework Silver certificate.

