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Sofyali, E.

Publications and source records attributed to Sofyali, E..

5 recordsLinked to original sources

A DNA foundation model predicts osteoporosis risk genes without proximity bias

Targets supported by human genetic associations are more than twice as likely to progress from clinical development to approval. Genome-wide association studies are the largest source of genetic evidence for disease risk but linking non-coding variants to effector genes remains a significant barrier to identifying causal targets. Current gene-mapping approaches suffer from proximity bias, largely ignoring distal genes. Here we introduce Rosalind, a DNA foundation model fine-tuned on human genetic variation from GTEx, that directly predicts variant-gene regulatory relationships from sequence without relying on nearest-gene heuristics. We demonstrate Rosalinds accuracy through extensive benchmarking, apply it to multiple complex traits to establish broad utility, and provide experimental validation in osteoporosis using a translational osteoblast assay. We demonstrate that genes distal to osteoporosis risk variants were significantly more likely to alter a bone formation phenotype than nearest genes. Together, these results highlight deep learning-based regulatory models as a general and scalable framework for translating novel genetic insights to drug discovery.

genetics↗

GLYATL1 is associated with metabolic and epigenetic changes and with endocrine resistance in luminal breast cancer

Estrogen receptor alpha (ER)-positive luminal breast cancer is commonly treated with aromatase inhibitors (AI) to block estrogen signaling; however, resistance frequently develops, limiting therapy success. We observed that GLYATL1 (Glycine-N-Acyltransferase Like 1) expression is upregulated in AI-resistant breast cancer cell models and in patients undergoing AI therapy, correlating with poorer survival. Here we demonstrate that GLYATL1 promotes resistance to estrogen deprivation by elevating succinate levels and altering epigenetic histone marks associated with active transcription. Knockdown or knockout of GLYATL1 reverses these effects and reduces proliferation under estrogen-deprived conditions. Notably, GLYATL1 expression is positively regulated by estrogen receptor alpha signaling independently of estrogen. These findings reveal GLYATL1 as a metabolic and epigenetic mediator of endocrine therapy resistance, suggesting it as a potential target to overcome AI resistance in luminal breast cancer.

cancer biology↗

Unperturbed dormancy recording reveals stochastic awakening strategies in endocrine treated breast cancer cells

Hormone dependent breast cancer (HDBC) is the most commonly diagnosed tumor type in women. Adjuvant endocrine therapies (ET) have been the cornerstone in the clinical management of HDBC patients for over forty years. A vast proportion of HDBC patients incur long periods of clinical dormancy following ET, with tumour awakening appearing at a steady pace for up to 25 years (Pan et al., 2017). Extensive genomic studies have demonstrated that 15-30% of clinical relapses develop recurrent genomic changes which contribute to drug resistance (i.e. ESR1 activating mutations) (Bertucci et al., 2019; Magnani et al., 2017; Razavi et al., 2018). However, even in these cases, there is no conclusive evidence around the pre-existence vs. de novo nature of these events. We previously showed that ETs can trigger and select for dormancy in subpopulations of breast cancer(Hong et al., 2019). In this work we took two novel approaches to investigate the dormancy and awakening roadmap of HDBC cells in unprecedented detail. Firstly, we leveraged a rare cohort of n=5 patients which were treated with primary adjuvant ETs in the absence of surgery (TRACING-HT) to dissect the contribution of genomic aberrations to tumor awakening. Next, we developed a first of its kind evolutionary study in vitro to systematically annotate cancer cells adaptive strategies at single cell level in unperturbed systems during a period of several months (TRADITIOM). Collectively our data suggest that ETs steer HDBC cells into an inherently unstable dormant state. Over time, routes to awakening emerge sporadically and spontaneously in single lineages. Each dormant cell retains an intrinsic awakening probability which we propose is a function of epigenetic decay. Awakening occurs without an external trigger and involves multiple apparent endpoint phenotypes that cannot be fully explained by conventional Darwinian genetic selection processes. Finally, our data show that common genetic hits associated with resistance happen downstream of awakening. Overall, our data have uncovered previously unsuspected roles for stochastic nongenetic events during dormancy with profound clinical implications.

cancer biology↗

Time-resolved profiling reveals ATF3 as a novel mediator of endocrine resistance in breast cancer

Breast cancer is one of the leading causes of death for women worldwide. Patients whose tumors express Estrogen Receptor (ER) account for around 70% of cases and are mostly treated with targeted endocrine therapy. However, 40% of these tumors eventually relapse due to resistance development and further treatment of these patients is highly ineffective. In this study we profiled the early phases of the resistance development process to uncover drivers of this phenomenon. Time-resolved analysis revealed that ATF3, a member of the ATF/CREB family of transcription factors, acts as a novel regulator of the response to therapy via rewiring of central signaling processes towards the adaptation to endocrine treatment. ATF3 was found to be essential in controlling crucial processes such as proliferation, cell cycle and apoptosis during the early response to treatment through the regulation of MAPK/AKT signaling pathways. Its essential role was confirmed in vivo in a mouse model and elevated expression of ATF3 was verified in patient datasets, adding clinical relevance to our findings. This study proposes ATF3 as a novel mediator of endocrine resistance development in breast cancer and elucidates its role in the regulation of downstream pathways activities.

cancer biology↗

Candidate methylation sites associated with endocrine therapy resistance in the TCGA ER+/HER2- breast cancer cohort

BackgroundEstrogen receptor (ER) positive breast cancer is often effectively treated with drugs that inhibit ER signaling, i.e., tamoxifen (TAM) and aromatase inhibitors (AIs). However, about 30% of ER+ breast cancer patients develop resistance to therapy leading to tumour recurrence. Changes in the methylation profile have been implicated as one of the mechanisms through which therapy resistance develops. Therefore, we aimed to identify methylation loci associated with endocrine therapy resistance. MethodsWe used genome-wide DNA methylation profiles of primary ER+ tumors from The Cancer Genome Atlas in combination with curated data on survival and treatment to predict development of endocrine resistance. Association of individual DNA methylation markers with survival was assessed using Cox proportional hazards models in a cohort of ER+/HER2- tumours (N=552) and two sub-cohorts corresponding to the endocrine treatment (AIs or TAM) that patients received (N=210 and N=172, respectively). Models were adjusted for clinical variables tumour stage, age, AI treatment and luminal subtype. We also identified signatures of multiple methylation loci associated with survival using Cox proportional hazards models with elastic net regularization. Individual markers and multivariable signatures were compared with DNA methylation profiles generated in a time course experiment using the T47D ER+ breast cancer cell line treated with tamoxifen or deprived from estrogen. ResultsWe identified 132, 9 and 1 CpGs for which DNA methylation is significantly associated with survival in the ER+/HER2-, TAM and AI cohorts respectively. Corresponding multi-locus signatures consisted of 171, 50 and 160 CpGs and showed a large overlap with the corresponding single-locus signatures. Single-locus signatures for the ER+/HER2- and TAM cohorts were conserved among the loci that were differentially methylated in endocrine-resistant T47D cells. Similarly, multi-locus signatures for the ER+/HER2- and AI cohorts were conserved in endocrine-resistant T47D cells. ConclusionsWe identified individual and multivariable DNA methylation markers associated with therapy resistance independently of luminal status. Our results suggest that these markers identified from primary tumours and prior to any endocrine treatment are associated with development of endocrine resistance.

bioinformatics↗