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Avgustinova, A.

Publications and source records attributed to Avgustinova, A..

2 recordsLinked to original sources

FADS1/2-mediated lipid metabolic reprogramming drives ferroptosis sensitivity in triple-negative breast cancer

Triple-negative breast cancer (TNBC) has limited therapeutic options, is highly metastatic and characterized by early recurrence. Lipid metabolism is generally deregulated in TNBC and might reveal vulnerabilities to be targeted or used as biomarkers with clinical value. Ferroptosis is a type of cell death caused by iron-dependent lipid peroxidation which is facilitated by the presence of polyunsaturated fatty acids (PUFA). Here we identify fatty acid desaturases 1 and 2 (FADS1/2), which are responsible for PUFA biosynthesis, lipid susceptible to peroxidation, to be highly expressed in a subset of TNBC with a poorer prognosis. Lipidomic analysis, coupled with functional metabolic assays, showed that FADS1/2 high-expressing TNBC are susceptible to ferroptosis-inducing agents and that targeting FADS1/2 renders those tumors ferroptosis-resistant. These findings were validated in vitro and in vivo in mouse and human-derived clinically relevant models and in a retrospective cohort of TNBC patients. One sentence summaryThe availability of intracellular PUFA depends on FADS1/2 desaturases, expressed at higher levels in aggressive triple-negative breast cancers highly susceptible to ferroptosis.

cancer biology↗

KDM6 demethylases mediate EWSR1-FLI1-driven oncogenic transformation in Ewing Sarcoma

Ewing Sarcoma (EwS) is an aggressive bone and soft tissue tumor driven by the fusion oncoprotein EWSR1-FLI1. This aberrant transcription factor binds to GGAA microsatellites, causing epigenetic reprogramming through the formation of active neo-enhancers in a permissive cellular context. Inhibition of the oncogene remains challenging and current efforts instead seek to exploit emergent epigenetic treatments targeting EWSR1-FLI1 cofactors. Here, stemming from the genome-wide redistribution of H3K27me3 upon expression of EWSR1-FLI1 in pediatric hMSC, we unravel the contribution of the H3K27me3 demethylases KDM6A and KDM6B in transcriptional activation at EWSR1-FLI1 enhancers. We found that KDM6A has a demethylase-independent role in recruiting the SWI/SNF member BRG1 at EWSR1-FLI1-primed enhancers containing single GGAA motif, which is critical for EwS tumor growth. Conversely, KDM6B demethylates H3K27me3 at EWSR1-FLI1-active enhancers containing multimeric GGAA repeats and its deletion synergizes with EZH2 inhibitors. Our results highlight KDM6 demethylases as EWSR1-FLI1 cofactors with potential for future targeted therapies.

cancer biology↗