HDAC6 Inhibitors Modulate Lys49 Acetylation and Membrane Localization of β-Catenin in Human iPSC-Derived Neuronal Cells

We examined the effects of isoform-specific histone deacetylase (HDAC) inhibitors on β-catenin posttranslational modifications in neural progenitor cells (NPCs) derived from human induced pluripotent stem cells (iPSCs). β-catenin is a multifunctional protein with important roles in the developing and adult central nervous system. Activation of the Wnt pathway results in stabilization and nuclear translocation of β-catenin, resulting in activation of multiple target genes. In addition, β-catenin forms a complex with cadherins at the plasma membrane as part of the adherens junctions. The N-terminus of β-catenin has phosphorylation, ubiquitination, and acetylation sites that regulate its stability and signaling. In the absence of a Wnt signal, Ser33, Ser37, and Thr41 are constitutively phosphorylated by glycogen synthase kinase 3β (GSK3β). β-Catenin phosphorylated at these sites is recognized by β-transducin repeat-containing protein (βTrCP), which results in ubiquitination and degradation by the ubiquitin-proteasome pathway. The N-terminal regulatory domain of β-catenin also includes Ser45, a phosphorylation site for Casein Kinase 1α (CK1α) and Lys49, which is acetylated by the acetyltransferase p300/CBP-associated factor (PCAF). The relevance of Lys49 acetylation and Ser45 phosphorylation to the function of β-catenin is an active area of investigation. We find that HDAC6 inhibitors increase Lys49 acetylation and Ser45 phosphorylation but do not affect Ser33, Ser37, and Thr41 phosphorylation. Lys49 acetylation results in decreased ubiquitination of β-catenin in the presence of proteasome inhibition. While increased Lys49 acetylation does not affect total levels of β-catenin, it results in increased membrane localization of β-catenin

Niche-Based Screening in Multiple Myeloma Identifies a Kinesin-5 Inhibitor with Improved Selectivity over Hematopoietic Progenitors

Novel therapeutic approaches are urgently required for multiple myeloma (MM). We used a phenotypic screening approach using co-cultures of MM cells with bone marrow stromal cells to identify compounds that overcome stromal resistance. One such compound, BRD9876, displayed selectivity over normal hematopoietic progenitors and was discovered to be an unusual ATP non-competitive kinesin-5 (Eg5) inhibitor. A novel mutation caused resistance, suggesting a binding site distinct from known Eg5 inhibitors, and BRD9876 inhibited only microtubule-bound Eg5. Eg5 phosphorylation, which increases microtubule binding, uniquely enhanced BRD9876 activity. MM cells have greater phosphorylated Eg5 than hematopoietic cells, consistent with increased vulnerability specifically to BRD9876’s mode of action. Thus, differences in Eg5-microtubule binding between malignant and normal blood cells may be exploited to treat multiple myeloma. Additional steps are required for further therapeutic development, but our results indicate that unbiased chemical biology approaches can identify therapeutic strategies unanticipated by prior knowledge of protein targets

Taloushallinnon opas voimisteluseuralle : Bounce Espoo ry

Opinnäytetyön tarkoituksena oli luoda taloushallinnon opas voimisteluseura Bounce Espoo ry:lle. Bounce Espoo ry on espoolainen trampoliinivoimisteluun erikoistunut seura. Opinnäytetyö toimii ohjeena nykyiselle tai mahdolliselle uudelle henkilölle, joka hoitaa yhdistyksen taloushallintoa. Opinnäytetyö aihe tuli toimeksiantona Bounce Espoo ry:ltä. Opas on toteutettu yhdistyksen tarpeiden mukaan. Opas hyödyttää toimeksiantajayhdistyksen lisäksi myös muita pieniä yhdistyksiä. Opinnäytetyö on toiminnallinen, ja se koostuu raporttiosuudesta sekä oppaasta. Opinnäytetyön teoriaosuudessa käsiteltiin yhdistyksen koko taloushallintoa ja oppaassa keskityttiin kirjanpitoon. Teoria pohjautuu yleisesti yhdistyksen toimintaan, taloushallintoon ja juridiikkaan. Tekijät laativat yhdistystä hyödyttävän oppaan, jota yhdistys voi hyödyntää usean vuoden ajan, ottaen huomioon muuttuvan lainsäädännön ja valtion asettamat säännökset. Opas selventää taloushallintoa teoreettisesti ja käytännön esimerkkien avulla.The purpose of this thesis was to create a financial administration manual for gymnastics club Bounce Espoo ry. Bounce Espoo ry is a gymnastics club that specializes in trampoline gymnastics. The thesis is a guide for the current or prospective future employee who takes care of the financial management of the association. The thesis was commissioned by Bounce Espoo ry. The guide has been drawn out according to the needs of the association. In addition to Bounce Espoo, the guide will benefit other small associations, too. Our thesis is functional and consists of a report part and a manual. The theoretical part of the thesis discusses the entire financial management of the association and the guide focuses on the accounts. The theory is based on the practices, financial and legal affairs of the association in general. We made a guide which benefits the association. The association can use the guide for several years, but they must take notice of potential changes in state laws and regulations. The guide clarifies financial management theoretically and with practical provides

Dependency of a therapy-resistant state of cancer cells on a lipid peroxidase pathway

Plasticity of the cell state has been proposed to drive resistance to multiple classes of cancer therapies, thereby limiting their effectiveness. A high-mesenchymal cell state observed in human tumours and cancer cell lines has been associated with resistance to multiple treatment modalities across diverse cancer lineages, but the mechanistic underpinning for this state has remained incompletely understood. Here we molecularly characterize this therapy-resistant high-mesenchymal cell state in human cancer cell lines and organoids and show that it depends on a druggable lipid-peroxidase pathway that protects against ferroptosis, a non-apoptotic form of cell death induced by the build-up of toxic lipid peroxides. We show that this cell state is characterized by activity of enzymes that promote the synthesis of polyunsaturated lipids. These lipids are the substrates for lipid peroxidation by lipoxygenase enzymes. This lipid metabolism creates a dependency on pathways converging on the phospholipid glutathione peroxidase (GPX4), a selenocysteine-containing enzyme that dissipates lipid peroxides and thereby prevents the iron-mediated reactions of peroxides that induce ferroptotic cell death. Dependency on GPX4 was found to exist across diverse therapy-resistant states characterized by high expression of ZEB1, including epithelial-mesenchymal transition in epithelial-derived carcinomas, TGFβ-mediated therapy-resistance in melanoma, treatment-induced neuroendocrine transdifferentiation in prostate cancer, and sarcomas, which are fixed in a mesenchymal state owing to their cells of origin. We identify vulnerability to ferroptic cell death induced by inhibition of a lipid peroxidase pathway as a feature of therapy-resistant cancer cells across diverse mesenchymal cell-state contexts