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Biology subjects

Schutkowski, M.

Publications and source records attributed to Schutkowski, M..

3 recordsLinked to original sources

Dona Flor and her two husbands: Discovery of novel HDAC6/AKT2 inhibitors for myeloid cancer treatment

Hematological cancer treatment with hybrid kinase/HDAC inhibitors is a novel strategy to overcome the challenge of acquired resistance to drugs. We collected IC50 datasets from the ChEMBL database for 13 cancer cell lines (72 h cytotoxicity, measured by MTT), known inhibitors for 38 kinases, and 10 HDACs isoforms, that we identified by target fishing and literature review. The data was subjected to rigorous biological and chemical curation leaving the final datasets ranging from 76 to 8173 compounds depending on the target. We generated Random Forest classification models, whereby 14 showed greater than 80% predictability after 5-fold external cross-validation. We screened 30 hybrid kinase/HDAC inhibitor analogs through each of these models. Fragment-contribution maps were constructed to aid the understanding of SARs and the optimization of these compounds as selective kinase/HDAC inhibitors for cancer treatment. Among the predicted compounds, 9 representative hybrids were synthesized and subjected to biological evaluation to validate the models. We observed high hit rates after biological testing for the following models: K562 (62.5%), MV4-11 (75.0%), MM1S (100%), NB-4 (62.5%), U937 (75.0), and HDAC6 (86.0%). This aided the identification of 6b and 6k as potent anticancer inhibitors with IC50 of 0.2-0.8 {micro}M in three cancer cell lines, linked to HDAC6 inhibition below 2 nM, and blockade of AKT2 phosphorylation at 2 M, validating the ability of our models to predict novel drug candidates. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=47 SRC="FIGDIR/small/626092v1_ufig1.gif" ALT="Figure 1"> View larger version (13K): org.highwire.dtl.DTLVardef@76705dorg.highwire.dtl.DTLVardef@1cb1d32org.highwire.dtl.DTLVardef@1e9cbdforg.highwire.dtl.DTLVardef@47b819_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LINovel kinase/HDAC inhibitors for cancer treatment were found using machine learning C_LIO_LI61 QSAR models for hematological cancers and its targets were built and validated C_LIO_LIK562, MV4-11, MM1S, NB-4, U937, and HDAC6 models had hit rates above 62.5% in tests C_LIO_LI6b and 6k presented potent IC50 of 0.2-0.8 {micro}M in three cancer cell lines C_LIO_LI6b and 6k inhibited HDAC6 below 2 nM, and blockade of AKT2 phosphorylation at 2 M C_LI

cancer biology↗

Novel hydroxamic acid derivative induces apoptosis and constrains autophagy in leukemic cells

IntroductionPosttranslational modification of proteins by reversible acetylation regulates key biological processes. Histone deacetylases (HDACs) catalyze protein deacetylation and are frequently dysregulated in tumors. This has spurred the development of HDAC inhibitors (HDACi). Such epigenetic drugs modulate protein acetylation, eliminate tumor cells, and are approved for the treatment of blood cancers. ObjectivesWe aimed to identify novel, nanomolar HDACi with increased potency over existing agents and selectivity for the cancer-relevant class I HDACs (HDAC1/-2/-3/-8). Moreover, we wanted to define how such drugs control the apoptosis-autophagy interplay. As test systems, we used human leukemic cells and embryonic kidney-derived cells. MethodsWe synthesized novel pyrimidine-hydroxamic acid HDACi (KH9/KH16/KH29) and performed in vitro activity assays and molecular modeling of their direct binding to HDACs. We analyzed how these HDACi affect leukemic cell fate, acetylation, and protein expression with flow cytometry and immunoblot. The publicly available DepMap database of CRISPR-Cas9 screenings was used to determine sensitivity factors across human leukemic cells. ResultsNovel HDACi show nanomolar activity against class I HDACs. These agents are superior to the clinically used hydroxamic acid HDACi vorinostat. Within the KH-series of compounds, KH16 (yanostat) is the most effective inhibitor of HDAC3 (IC50 = 6 nM) and the most potent inducer of apoptosis (IC50 = 110 nM; p<0.0001) in leukemic cells. KH16 though spares embryonic kidney-derived cells. Global data analyses of knockout screenings verify that HDAC3 is a dependency factor in human blood cancer cells of different lineages, independent of mutations in the tumor suppressor p53. KH16 alters pro- and anti-apoptotic protein expression, stalls cell cycle progression, and induces a caspase-dependent processing of the autophagy proteins ULK1 and p62. ConclusionThese data reveal that HDACs are required to stabilize autophagy proteins through a suppression of apoptosis in leukemic cells. HDAC3 appears as a valid anti-cancer target for pharmacological intervention. HighlightsO_LINovel HDACi with nanomolar activity against leukemic cells were synthesized. C_LIO_LIHDACi of the KH-series are superior to a clinical grade HDACi. C_LIO_LIHDACi of the KH-series modulate acetylation and phosphorylation of proteins. C_LIO_LIThe new HDACi KH16 regulates cell cycle arrest, apoptosis, and autophagy. C_LIO_LIApoptosis acts upstream of autophagy in KH16-treated cells. C_LI

pharmacology and toxicology↗

HDAC11 is a fatty-acid deacylase

Histone deacetylase 11 (HDAC11) is a sole member of the class IV HDAC subfamily with negligible intrinsic deacetylation activity. Here we report in vitro profiling of HDAC11 deacylase activities, and our data unequivocally show that the enzyme efficiently removes acyl moieties spanning 8-18 carbons from the side chain nitrogen of the lysine residue of a peptidic substrate. Additionally, N-linked lipoic acid and biotin are removed by the enzyme, although with lower efficacy. Catalytic efficiencies toward dodecanoylated and myristoylated peptides exceed 70,000 M-1s-1 making HDAC11 the most proficient fatty acid deacylase of the HDAC family. Interestingly, HDAC11 is strongly inhibited by free myristic, palmitic and stearic acids with inhibition constants of 6.5 {micro}M, 0.9 {micro}M, and 1.6 {micro}M, respectively. At the same time, its deacylase activity is stimulated more than 2.5-fold by both palmitoyl-coenzyme A and myristoyl-coenzyme A, pointing toward metabolic control of the enzymatic activity by fatty acid metabolites. Our data reveal novel enzymatic activity of HDAC11 that can, in turn, facilitate the uncovering of additional biological functions of the enzyme as well as the design of isoform-specific HDAC inhibitors.

biochemistry↗