Progression through the cell cycle is driven by cyclin-dependent kinases that control gene expression, orchestration of mitotic spindle, and cell division. To identify new regulators of the cell cycle, we performed transcriptomic analysis of human non-transformed cells expressing a fluorescent ubiquitination-based cell cycle indicator and identified 701 transcripts differentially expressed in G1 and G2 cells. Family with sequence similarity 110 member A (FAM110A) protein is highly expressed in G2 cells and localized at mitotic spindle and spindle poles during mitosis. Depletion of FAM110A impairs chromosomal alignment, delays metaphase-to-anaphase transition, and affects spindle positioning. Using mass spectrometry and immunoprecipitation, we identified casein kinase I (CK1) in complex with FAM110A during mitosis. CK1 phosphorylates the C-terminal domain of FAM110A in vitro, and inhibition of CK1 reduces phosphorylation of mitotic FAM110A. Wild-type FAM110A, but not the FAM110A-S252-S255A mutant deficient in CK1 phosphorylation, rescues the chromosomal alignment, duration of mitosis, and orientation of the mitotic spindle after depletion of endogenous FAM110A. We propose that CK1 regulates chromosomal alignment by phosphorylating FAM110A and promoting its interaction with mitotic spindle.

• Klíčová slova
• G2 phase, casein kinase 1, cell cycle, chromosomal alignment, mitosis,
• MeSH
• anafáze MeSH
• aparát dělícího vřeténka * metabolismus   MeSH
• fosforylace MeSH
• HeLa buňky MeSH
• lidé MeSH
• mitóza genetika   MeSH
• proteiny buněčného cyklu * metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• proteiny buněčného cyklu * MeSH

The casein kinase 1 enzymes (CK1) form a family of serine/threonine kinases with seven CK1 isoforms identified in humans. The most important substrates of CK1 kinases are proteins that act in the regulatory nodes essential for tumorigenesis of hematological malignancies. Among those, the most important are the functions of CK1s in the regulation of Wnt pathways, cell proliferation, apoptosis and autophagy. In this review we summarize the recent developments in the understanding of biology and therapeutic potential of the inhibition of CK1 isoforms in the pathogenesis of chronic lymphocytic leukemia (CLL), other non-Hodgkin lymphomas (NHL), myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and multiple myeloma (MM). CK1δ/ε inhibitors block CLL development in preclinical models via inhibition of WNT-5A/ROR1-driven non-canonical Wnt pathway. While no selective CK1 inhibitors have reached clinical stage to date, one dual PI3Kδ and CK1ε inhibitor, umbralisib, is currently in clinical trials for CLL and NHL patients. In MDS, AML and MM, inhibition of CK1α, acting via activation of p53 pathway, showed promising preclinical activities and the first CK1α inhibitor has now entered the clinical trials.

• Klíčová slova
• AML, CK1α, CK1ε, CLL, MM, WNT pathway, casein kinase 1, inhibitors, leukemia, umbralisib,
• MeSH
• cílená molekulární terapie * MeSH
• hematologické nádory farmakoterapie   enzymologie   patologie   MeSH
• kaseinkinasa I antagonisté a inhibitory   chemie   metabolismus   MeSH
• lidé MeSH
• nádorové kmenové buňky účinky léků   metabolismus   patologie   MeSH
• protinádorové látky farmakologie   terapeutické užití   MeSH
• signální dráha Wnt MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• kaseinkinasa I MeSH
• protinádorové látky MeSH

INTRODUCTION: Breast cancer is one of the most common types of cancer in women. One of the genes that were found mutated in breast cancer is casein kinase 1 epsilon (CK1epsilon). Because CK1epsilon is a crucial regulator of the Wnt signaling cascades, we determined how these CK1epsilon mutations interfere with the Wnt pathway and affect the behavior of epithelial breast cancer cell lines. METHODS: We performed in silico modeling of various mutations and analyzed the kinase activity of the CK1epsilon mutants both in vitro and in vivo. Furthermore, we used reporter and small GTPase assays to identify how mutation of CK1epsilon affects different branches of the Wnt signaling pathway. Based on these results, we employed cell adhesion and cell migration assays in MCF7 cells to demonstrate a crucial role for CK1epsilon in these processes. RESULTS: In silico modeling and in vivo data showed that autophosphorylation at Thr 44, a site adjacent to the breast cancer point mutations in the N-terminal lobe of human CK1epsilon, is involved in positive regulation of the CK1epsilon activity. Our data further demonstrate that, in mammalian cells, mutated forms of CK1epsilon failed to affect the intracellular localization and phosphorylation of Dvl2; we were able to demonstrate that CK1epsilon mutants were unable to enhance Dvl-induced TCF/LEF-mediated transcription, that CK1epsilon mutants acted as loss-of-function in the Wnt/beta-catenin pathway, and that CK1epsilon mutants activated the noncanonical Wnt/Rac-1 and NFAT pathways, similar to pharmacological inhibitors of CK1. In line with these findings, inhibition of CK1 promoted cell migration as well as decreased cell adhesion and E-cadherin expression in the breast cancer-derived cell line MCF7. CONCLUSIONS: In summary, these data suggest that the mutations of CK1epsilon found in breast cancer can suppress Wnt/beta-catenin as well as promote the Wnt/Rac-1/JNK and Wnt/NFAT pathways, thus contributing to breast cancer development via effects on cell adhesion and migration. In terms of molecular mechanism, our data indicate that the breast cancer point mutations in the N-terminal lobe of CK1epsilon, which are correlated with decreased phosphorylation activities of mutated forms of CK1epsilon both in vitro and in vivo, interfere with positive autophosphorylation at Thr 44.

• MeSH
• beta-katenin metabolismus   MeSH
• buněčná adheze MeSH
• duktální karcinom prsu genetika   metabolismus   patologie   MeSH
• fosforylace MeSH
• imunoprecipitace MeSH
• kaseinkinasa Iepsilon chemie   genetika   metabolismus   MeSH
• konformace proteinů MeSH
• lidé MeSH
• MAP kinasa-kinasa 4 metabolismus   MeSH
• messenger RNA genetika   MeSH
• mutace genetika   MeSH
• nádorové buněčné linie MeSH
• nádory prsu genetika   metabolismus   patologie   MeSH
• pohyb buněk * MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• proliferace buněk MeSH
• proteiny Wnt metabolismus   MeSH
• rac1 protein vázající GTP metabolismus   MeSH
• transkripční faktory NFATC metabolismus   MeSH
• western blotting MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• beta-katenin MeSH
• kaseinkinasa Iepsilon MeSH
• MAP kinasa-kinasa 4 MeSH
• messenger RNA MeSH
• proteiny Wnt MeSH
• rac1 protein vázající GTP MeSH
• RAC1 protein, human MeSH Prohlížeč
• transkripční faktory NFATC MeSH