The LSD1 inhibitor iadademstat (ORY-1001) targets SOX2-driven breast cancer stem cells: a potential epigenetic therapy in luminal-B and HER2-positive breast cancer subtypes

SOX2 is a core pluripotency-associated transcription factor causally related to cancer initiation, aggressiveness, and drug resistance by driving the self-renewal and seeding capacity of cancer stem cells (CSC). Here, we tested the ability of the clinically proven inhibitor of the lysine-specific demethylase 1 (LSD1/KDM1A) iadademstat (ORY-100) to target SOX2-driven CSC in breast cancer. Iadademstat blocked CSC-driven mammosphere formation in breast cancer cell lines that are dependent on SOX2 expression to maintain their CSC phenotype. Iadademstat prevented the activation of an LSD1-targeted stemness-specific SOX2 enhancer in CSC-enriched 3-dimensional spheroids. Using high-throughput transcriptional data available from the METABRIC dataset, high expression of SOX2 was significantly more common in luminal-B and HER2-enriched subtypes according to PAM50 classifier and in IntClust1 (high proliferating luminal-B) and IntClust 5 (luminal-B and HER2-amplified) according to integrative clustering. Iadademstat significantly reduced mammospheres formation by CSC-like cells from a multidrug-resistant luminal-B breast cancer patient-derived xenograft but not of those from a treatment-naive luminal-A patient. Iadademstat reduced the expression of SOX2 in luminal-B but not in luminal-A mammospheres, likely indicating a selective targeting of SOX2-driven CSC. The therapeutic relevance of targeting SOX2-driven breast CSC suggests the potential clinical use of iadademstat as an epigenetic therapy in luminal-B and HER2-positive subtypes

Extra Virgin Olive Oil Contains a Phenolic Inhibitor of the Histone Demethylase LSD1/KDM1A

The lysine-specific histone demethylase 1A (LSD1) also known as lysine (K)-specific demethylase 1A (KDM1A) is a central epigenetic regulator of metabolic reprogramming in obesity-associated diseases, neurological disorders, and cancer. Here, we evaluated the ability of oleacein, a biophenol secoiridoid naturally present in extra virgin olive oil (EVOO), to target LSD1. Molecular docking and dynamic simulation approaches revealed that oleacein could target the binding site of the LSD1 cofactor flavin adenosine dinucleotide with high affinity and at low concentrations. At higher concentrations, oleacein was predicted to target the interaction of LSD1 with histone H3 and the LSD1 co-repressor (RCOR1/CoREST), likely disturbing the anchorage of LSD1 to chromatin. AlphaScreen-based in vitro assays confirmed the ability of oleacein to act as a direct inhibitor of recombinant LSD1, with an IC50 as low as 2.5 umol/L. Further, oleacein fully suppressed the expression of the transcription factor SOX2 (SEX determining Region Y-box 2) in cancer stem-like and induced pluripotent stem (iPS) cells, which specifically occurs under the control of an LSD1-targeted distal enhancer. Conversely, oleacein failed to modify ectopic SOX2 overexpression driven by a constitutive promoter. Overall, our findings provide the first evidence that EVOO contains a naturally occurring phenolic inhibitor of LSD1, and support the use of oleacein as a template to design new secoiridoid-based LSD1 inhibitors.Work in the Menendez laboratory is supported by the Spanish Ministry of Science and Innovation (Grant SAF2016-80639-P, Plan Nacional de l+D+I, founded by the European Regional Development Fund, Spain) and by an unrestricted research grant from the Fundació Oncolliga Girona (Lliga catalana d’ajuda al malalt de càncer, Girona). The Spanish Ministry of Economy and Competitiveness (MINECO, Project RTI2018-096724-B-C21) and the Generalitat Valenciana (PROMETEO/2016/006) supports work in the Encinar laborator

Mimetics of extra virgin olive oil phenols with anti-cancer stem cell activity

The extra virgin olive oil (EVOO) dihydroxy-phenol oleacein is a natural inhibitor of multiple metabolic and epigenetic enzymes capable of suppressing the functional traits of cancer stem cells (CSC). Here, we used a natural product-inspired drug discovery approach to identify new compounds that phenotypically mimic the anti-CSC activity of oleacein. We coupled 3D quantitative structure-activity relationship-based virtual profiling with phenotypic analysis using 3D tumorsphere formation as a gold standard for assessing the presence of CSC. Among the top 20 computationally-predicted oleacein mimetics, four fulfilled the phenotypic endpoint of specifically suppressing the tumorsphere-initiating capacity of CSC, in the absence of significant cytotoxicity against differentiated cancer cells growing in 2D cultures in the same low micromolar concentration range. Of these, 3,4-dihydrophenetyl butyrate –a lipophilic ester conjugate of the hydroxytyrosol moiety of oleacein– and (E)-N-allyl-2-((5-nitrofuran-2-yl)methylene)hydrazinecarbothioamide) –an inhibitor of Trypanosoma cruzi triosephosphate isomerase– were also highly effective at significantly reducing the proportion of aldehyde dehydrogenase (ALDH)-positive CSC-like proliferating cells. Preservation of the mTOR/DNMT binding mode of oleacein was dispensable for suppression of the ALDH+-CSC functional phenotype in hydroxytyrosol-unrelated mimetics. The anti-CSC chemistry of complex EVOO phenols such as oleacein can be phenocopied through the use of mimetics capturing its physico-chemical properties.Work in the Menendez laboratory is supported by the Spanish Ministry of Science and Innovation (Grants SAF2016-80639-P and PID2019-104055GB-I00, Plan Nacional de I+D+I, founded by the European Regional Development Fund, Spain) and by an unrestricted research grant from the Fundació Oncolliga Girona (Lliga catalana d’ajuda al malalt de càncer, Girona). Joaquim Bosch-Barrera is the recipient of research grants from La Marató de TV3 foundation (201906) and the Health Research and Innovation Strategic Plan (SLT006/17/114; PERIS 2016-2020; Pla stratègic de recerca i innovació en salut; Departament de Salut, Generalitat de Catalunya).Peer reviewe