TP53 variant clusters stratify phenotypic diversity in germline carriers and reveal an osteosarcoma-prone subgroup

Sep 23, 2026

Uploaded by Ben

TP53 variant clusters are used to stratify phenotypic diversity among germline carriers and to expose a subgroup predisposed to anosteosarcoma. The work applies unsupervised clustering to functional datasets, identifies clinically relevant TP53 variant groups, and highlights a monomeric cluster enriched in osteosarcoma. In cellular validation assays, dermal fibroblasts from carriers of more functionally impaired variants show increased metabolic growth rates, aligning with cluster-stratified clinical outcome trends. Results support developing diagnostic assays for personalized cancer risk assessment and functionally delineating variant carriers across the TP53 susceptibility spectrum in Li-Fraumeni syndrome.

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CategoryHealthcare

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Article Overview

Li-Fraumeni Syndrome and TP53 Variant Heterogeneity

Need for Risk Stratification and Functional Classification

Article [https://doi.org/10.1038/s41467-025-63528-6](https://doi.org/10.1038/s41467-025-63528-6) TP53 variant clusters stratify phenotypic diversity in germline carriers and reveal anosteosarcoma-prone subgroup Received: 12 February 2024 | Accepted: 21 August 2025 | | --- | | | | Check for updates | Nicholas W. Fischer 1 , Noel Ong1,2, Brianne Laverty 1,2, Pamela Psarianos1,2, Camilla Giovino1,2, Noa Alon1, Emilie Montellier 3, Pierre Hainaut 3,11, Kara N. Maxwell 4,5, Christian P. Kratz 6, Ran Kafri7,8 & David Malkin 1,2,9,10 Li-Fraumeni syndrome (LFS) has recently been redeﬁned as a ‘spectrum’ cancer predisposition disorder to reﬂect its broad phenotypic heterogeneity. This variability is thought to stem in part from the diverse functional impacts of TP53 variants, although the underlying mechanisms remain poorly understood and there is an unmet clinical need for effective risk stratiﬁcation. Here, we apply unsupervised clustering to functional datasets and identify distinct TP53 variant groups with clinical relevance, including a monomeric subgroup enriched in osteosarcoma cases. In cellular validation assays, dermal ﬁbroblasts from carriers of more functionally impaired variants exhibit increased metabolic growth rates, mirroring trends observed in cluster-stratiﬁed clinical outcomes. These ﬁndings demonstrate the feasibility of developing diagnostic assays to guide personalized cancer risk assessment. More broadly, our results show that nuances inTP53dysfunction shape the germline TP53-related cancer susceptibility spectrum and provide a framework for functionally delineating variant carriers. Inherited cancer susceptibility in Li-Fraumeni Syndrome (LFS; MIM \#151623) was ﬁrst described in 1969 based on the observation of several families with a high incidence of rare and diverse cancer types1. Since this initial observation, germline TP53 variants were identiﬁed asthe underlying cause of LFS2,3 and the clinical classiﬁcation has been adapted by multiple revised sets of criteria4–7 to incorporate individuals who do not ﬁt the strict ‘classic LFS’ diagnosis8. Recently, LFS was reclassiﬁed as a ‘spectrum’ of disease rather than a syndrome to reﬂect the heterogeneity that has become increasingly evident through genotype-phenotype association studies9. The LFS spectrum encompasses a highly variable age-of-onset with nearly 30% affected during childhood, largely unpredictable sites of tumor manifestation, and inconsistent cancer penetrance. To date, the factors causing this heterogeneity in LFS remain unclear, although unequal TP53 variant functional consequences have been linked to different cancer phenotypes10–12. Increased use of DNA sequencing in the clinic has led to the discovery ofhundreds ofgermline variants that span the entire TP53gene. Missense mutations leading to single amino acid changes represent the vast majority of TP53 variants that are associated with LFS. There are thousands of possible single amino acid substitutions in TP53, and currently, at least 1,703 different germline variants have been linked to 1Program in Genetics & Genome Biology, The Hospital for Sick Children, Toronto, Canada. 2Department of Medical Biophysics, University of Toronto, Toronto, Canada. 3Institute for Advanced Biosciences, Université Grenoble Alpes, Grenoble, France. 4Division of Hematology-Oncology, Department of Medicine, Perelman School of Medicine atthe University of Pennsylvania, Philadelphia, PA, USA. 5Department of Genetics, Perelman School of Medicine atthe University of Pennsylvania, Philadelphia, PA, USA. 6Pediatric Hematology and Oncology, Hannover Medical School, Hannover, Germany. 7Department of Molecular Genetics, University of Toronto, Toronto, Canada. 8Program in Cell Biology, The Hospital for Sick Children, Toronto, Canada. 9Division of Hematology-Oncology, The Hospital for Sick Children, Toronto, Canada. 10Department of Pediatrics, The Hospital for Sick Children, Toronto, Canada. 11Deceased:

FAQs

What is the main goal of the study involving TP53 variant clusters?

To classify TP53 variants into clinically relevant groups using unsupervised clustering and to link these groups to phenotypic diversity in germline carriers.

Which subgroup is highlighted as osteosarcoma prone?

A monomeric subgroup is enriched in osteosarcoma cases.

How do cellular validation results relate to clinical outcomes?

Dermal fibroblasts from carriers with more functionally impaired variants show increased metabolic growth rates, mirroring trends seen in cluster-stratified clinical outcomes.

Sep 23, 2026

Uploaded by Ben