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Flanagan, A. M.

Publications and source records attributed to Flanagan, A. M..

3 recordsLinked to original sources

Epigenetic inactivation of oncogenic brachyury (TBXT) by H3K27 histone demethylase controls chordoma cell survival

The expression of the transcription factor brachyury (TBXT) is normally restricted to embryonic development and its silencing after mesoderm development is epigenetically regulated. In chordoma, a rare tumour of notochordal differentiation, TBXT acts as a putative oncogene, and we hypothesised that its expression could be controlled through epigenetic inhibition. Screening of five chordoma cell lines revealed that only inhibitors of the histone 3 lysine 27 demethylases KDM6A (UTX) and KDM6B (Jmjd3) reduce TBXT expression and lead to cell death, findings validated in primary patient-derived culture systems. Pharmacological inhibition of KDM6 demethylases leads to genome-wide increases in repressive H3K27me3 marks, accompanied by significantly reduced TBXT expression, an effect that is phenocopied by the dual genetic inactivation of KDM6A/B using CRISPR/Cas9. Transcriptional profiles in response to a novel KDM6A/B inhibitor, KDOBA67, revealed downregulation of critical genes and transcription factor networks for chordoma survival pathways, whereas upregulated pathways were dominated by stress, cell cycle and pro-apoptotic response pathways.\n\nThis study supports previous data showing that the function of TBXT is essential for maintaining notochord cell fate and function and provides further evidence that TBXT is an oncogenic driver in chordoma. Moreover, the data suggest that TBXT can potentially be targeted therapeutically by modulating epigenetic control mechanisms such as H3K27 demethylases.

cancer biology

A novel innate lymphoid cell delineates childhood autoimmune arthritis

Inflammation in autoimmune disease is mediated by a complex network of interacting cells. Their identity and cross-talk are encoded in messenger RNA (mRNA). Juvenile idiopathic arthritis (JIA), a chronic autoimmune arthritis of childhood, is characterised by synovial inflammation with infiltration of both innate and adaptive immune cells1. Activated T cells play a role in disease2 but the cell types that drive the recruitment and activation of immune cells within the synovium are not known. Here, we utilised droplet-based and full length single cell mRNA sequencing to obtain a quantitative map of the cellular landscape of JIA. We studied 45,715 cells from the synovial fluid of inflamed knee joints and peripheral blood. We identified a population of synovial innate lymphoid cells (ILCs), shared across patients, that exhibited a unique transcriptional profile in comparison to canonical ILC subtypes. Validation at protein-level across a spectrum of autoimmune arthritides revealed that these ILCs are pathologically expanded in a particular type of JIA. Using statistical tools to assess cellular interactions in synovial fluid, ILCs emerged as a central node of communication, expressing the full repertoire of genes required to orchestrate and maintain the inflammatory milieu. Several ILC-mediated signalling pathways may lend themselves as novel therapeutic targets. Together our findings demonstrate a distinct ILC subtype associated with a tissue-specific childhood autoimmune disease.

immunology

PGP-UK: a research and citizen science hybrid project in support of personalized medicine

Molecular analyses such as whole-genome sequencing have become routine and are expected to be transformational for future healthcare and lifestyle decisions. Population-wide implementation of such analyses is, however, not without challenges, and multiple studies are ongoing to identify what these are and explore how they can be addressed. Defined as a research project, the Personal Genome Project UK (PGP-UK) is part of the global PGP network and focuses on open data sharing and citizen science to advance and accelerate personalized genomics and medicine. Here we report our findings on using an open consent recruitment protocol, active participant involvement, open access release of personal genome, methylome and transcriptome data and associated analyses, including 47 new variants predicted to affect gene function and innovative reports based on the analysis of genetic and epigenetic variants. For this pilot study, we recruited ten participants willing to actively engage as citizen scientists with the project. In addition, we introduce Genome Donation as a novel mechanism for openly sharing previously restricted data and discuss the first three donations received. Lastly, we present GenoME, a free, open-source educational app suitable for the lay public to allow exploration of personal genomes. Our findings demonstrate that citizen science-based approaches like PGP-UK have an important role to play in the public awareness, acceptance and implementation of genomics and personalized medicine.

genomics