Bruton tyrosine kinase (BTK) inhibitor therapy induces peripheral blood lymphocytosis in chronic lymphocytic leukemia (CLL), which lasts for several months. It remains unclear whether nongenetic adaptation mechanisms exist, allowing CLL cells' survival during BTK inhibitor-induced lymphocytosis and/or playing a role in therapy resistance. We show that in approximately 70% of CLL cases, ibrutinib treatment in vivo increases Akt activity above pretherapy levels within several weeks, leading to compensatory CLL cell survival and a more prominent lymphocytosis on therapy. Ibrutinib-induced Akt phosphorylation (pAktS473) is caused by the upregulation of Forkhead box protein O1 (FoxO1) transcription factor, which induces expression of Rictor, an assembly protein for the mTORC2 protein complex that directly phosphorylates Akt at serine 473 (S473). Knockout or inhibition of FoxO1 or Rictor led to a dramatic decrease in Akt phosphorylation and growth disadvantage for malignant B cells in the presence of ibrutinib (or PI3K inhibitor idelalisib) in vitro and in vivo. The FoxO1/Rictor/pAktS473 axis represents an early nongenetic adaptation to B cell receptor (BCR) inhibitor therapy not requiring PI3Kδ or BTK kinase activity. We further demonstrate that FoxO1 can be targeted therapeutically and its inhibition induces CLL cells' apoptosis alone or in combination with BTK inhibitors (ibrutinib, acalabrutinib, pirtobrutinib) and blocks their proliferation triggered by T cell factors (CD40L, IL-4, and IL-21).

• MeSH
• adenin * analogy a deriváty   farmakologie   MeSH
• chronická lymfatická leukemie * farmakoterapie   metabolismus   genetika   patologie   MeSH
• forkhead box protein O1 * metabolismus   genetika   MeSH
• fosforylace MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádorové proteiny metabolismus   genetika   MeSH
• piperidiny * farmakologie   MeSH
• protein RICTOR * genetika   metabolismus   MeSH
• proteinkinasa BTK metabolismus   genetika   antagonisté a inhibitory   MeSH
• protoonkogenní proteiny c-akt * metabolismus   genetika   MeSH
• pyrazoly * farmakologie   MeSH
• pyrimidiny * farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Recirculation of chronic lymphocytic leukemia (CLL) cells between the peripheral blood and lymphoid niches plays a critical role in disease pathophysiology, and inhibiting this process is one of the major mechanisms of action for B-cell receptor (BCR) inhibitors such as ibrutinib and idelalisib. Migration is a complex process guided by chemokine receptors and integrins. However, it remains largely unknown how CLL cells integrate multiple migratory signals while balancing survival in the peripheral blood and the decision to return to immune niches. Our study provided evidence that CXCR4/CD5 intraclonal subpopulations can be used to study the regulation of migration of CLL cells. We performed RNA profiling of CXCR4dimCD5bright vs CXCR4brightCD5dim CLL cells and identified differential expression of dozens of molecules with a putative function in cell migration. GRB2-associated binding protein 1 (GAB1) positively regulated CLL cell homing capacity of CXCR4brightCD5dim cells. Gradual GAB1 accumulation in CLL cells outside immune niches was mediated by FoxO1-induced transcriptional GAB1 activation. Upregulation of GAB1 also played an important role in maintaining basal phosphatidylinositol 3-kinase (PI3K) activity and the "tonic" AKT phosphorylation required to sustain the survival of resting CLL B cells. This finding is important during ibrutinib therapy, because CLL cells induce the FoxO1-GAB1-pAKT axis, which represents an adaptation mechanism to the inability to home to immune niches. We have demonstrated that GAB1 can be targeted therapeutically by novel GAB1 inhibitors, alone or in combination with BTK inhibition. GAB1 inhibitors induce CLL cell apoptosis, impair cell migration, inhibit tonic or BCR-induced AKT phosphorylation, and block compensatory AKT activity during ibrutinib therapy.

• MeSH
• adaptorové proteiny signální transdukční biosyntéza   MeSH
• adenin analogy a deriváty   farmakologie   MeSH
• chronická lymfatická leukemie farmakoterapie   metabolismus   patologie   MeSH
• forkhead box protein O1 metabolismus   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• piperidiny farmakologie   MeSH
• pohyb buněk * MeSH
• protoonkogenní proteiny c-akt metabolismus   MeSH
• regulace genové exprese u leukemie * MeSH
• signální transdukce * MeSH
• upregulace * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cardiovascular complications are a side effect of cancer therapy, potentially through reduced blood vessel function. ONC201 (TIC10) is currently used in phase 2 clinical trials to treat high-grade gliomas. TIC10 is a phosphatidylinositol 3-kinase (PI3K)/AKT/extracellular signal-regulated kinase (ERK) inhibitor that induces apoptosis via upregulation of TNF-related apoptosis-inducing ligand, which via stimulation of FOXO and death receptor could increase eNOS upregulation. This has the potential to improve vascular function through increased NO bioavailability. Our aim was to investigate the role of TIC10 on vascular function to determine if it would affect the risk of CVD. Excised abdominal aorta from White New Zealand male rabbits were cut into rings. Vessels were incubated with TIC10 and AS1842856 (FOXO1 inhibitor) followed by cumulative doses of acetylcholine (Ach) to assess vessel function. Vessels were then processed for immunohistochemistry. Incubation of blood vessels with TIC10 resulted in enhanced vasodilatory capacity. Combination treatment with the FOXO1 inhibitor and TIC10 resulted in reduced vascular function compared to control. Immunohistochemical analysis indicated a 3-fold increase in death receptor 5 (DR5) expression in the TIC10-treated blood vessels but the addition of the FOXO1 inhibitor downregulated DR5 expression. The expression of DR4 receptor was not significantly increased in the presence of TIC10; however, addition of the FOXO1 inhibitor downregulated expression. TIC10 has the capacity to improve the function of healthy vessels when stimulated with the vasodilator Ach. This highlights its therapeutic potential not only in cancer treatment without cardiovascular side effects, but also as a possible drug to treat established CVD.

• MeSH
• fosfatidylinositol-3-kinasy MeSH
• imidazoly * MeSH
• králíci MeSH
• lidé MeSH
• protein FOXO3 * MeSH
• protein TRAIL MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The proapoptotic protein Noxa, a member of the BH3-only Bcl-2 protein family, can effectively induce apoptosis in cancer cells, although the relevant regulatory pathways have been obscure. Previous studies of the cytotoxic effects of α-tocopheryl succinate (α-TOS) on cancer cells identified a mechanism whereby α-TOS caused apoptosis requiring the Noxa-Bak axis. In the present study, ab initio analysis revealed a conserved FoxO-binding site (DBE; DAF-16 binding element) in the NOXA promoter, and specific affinity of FoxO proteins to this DBE was confirmed by fluorescence anisotropy. FoxO1 and FoxO3a proteins accumulated in the nucleus of α-TOS-treated cells, and the drug-induced specific FoxO1 association with the NOXA promoter and its activation were validated by chromatin immunoprecipitation. Using siRNA knockdown, a specific role for the FoxO1 protein in activating NOXA transcription in cancer cells was identified. Furthermore, the proapoptotic kinase Hippo/Mst1 was found to be strongly activated by α-TOS, and inhibiting Hippo/Mst1 by specific siRNA prevented phosphorylation of FoxO1 and its nuclear translocation, thereby reducing levels of NOXA transcription and apoptosis in cancer cells exposed to α-TOS. Thus, we have demonstrated that anticancer drugs, exemplified by α-TOS, induce apoptosis by a mechanism involving the Hippo/Mst1-FoxO1-Noxa pathway. We propose that activation of this pathway provides a new paradigm for developing targeted cancer treatments.

• MeSH
• alfa-tokoferol farmakologie   MeSH
• apoptóza fyziologie   MeSH
• forkhead transkripční faktory genetika   metabolismus   MeSH
• genetická transkripce MeSH
• Jurkat buňky MeSH
• lidé MeSH
• lymfom T-buněčný genetika   metabolismus   patologie   terapie   MeSH
• malá interferující RNA aplikace a dávkování   genetika   MeSH
• nádorové buněčné linie MeSH
• nádory plic genetika   metabolismus   patologie   terapie   MeSH
• nemalobuněčný karcinom plic genetika   metabolismus   patologie   terapie   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• promotorové oblasti (genetika) MeSH
• protein-serin-threoninkinasy antagonisté a inhibitory   genetika   metabolismus   MeSH
• protoonkogenní proteiny c-bcl-2 biosyntéza   genetika   metabolismus   MeSH
• signální transdukce MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• cévní endotel účinky léků   MeSH
• diabetes mellitus * farmakoterapie   metabolismus   MeSH
• forkhead transkripční faktory genetika   metabolismus   MeSH
• glukosa metabolismus   škodlivé účinky   MeSH
• metformin * farmakologie   terapeutické užití   MeSH
• oxidační stres účinky léků   MeSH
• transkripční faktory BHLH-Zip genetika   metabolismus   MeSH

FOXO transcription factors regulate cellular homeostasis, longevity and response to stress. FOXO1 (also known as FKHR) is a key regulator of hepatic glucose production and lipid metabolism, and its specific inhibition may have beneficial effects on diabetic hyperglycemia by reducing hepatic glucose production. Moreover, all FOXO proteins are considered potential drug targets for drug resistance prevention in cancer therapy. However, the development of specific FOXO inhibitors requires a detailed understanding of structural differences between individual FOXO DNA-binding domains. The high-resolution structure of the DNA-binding domain of FOXO1 reported in this study and its comparison with structures of other FOXO proteins revealed differences in both their conformation and flexibility. These differences are encoded by variations in protein sequences and account for the distinct functions of FOXO proteins. In particular, the positions of the helices H1, H2 and H3, whose interface form the hydrophobic core of the Forkhead domain, and the interactions between hydrophobic residues located on the interface between the N-terminal segment, the H2-H3 loop, and the recognition helix H3 differ among apo FOXO1, FOXO3 and FOXO4 proteins. Therefore, the availability of apo structures of DNA-binding domains of all three major FOXO proteins will support the development of FOXO-type-specific inhibitors.

• MeSH
• forkhead box protein O1 chemie   genetika   metabolismus   MeSH
• forkhead transkripční faktory chemie   genetika   metabolismus   MeSH
• hydrofobní a hydrofilní interakce MeSH
• lidé MeSH
• magnetická rezonanční spektroskopie MeSH
• molekulární modely MeSH
• myši MeSH
• protein FOXO3 chemie   genetika   metabolismus   MeSH
• proteinové domény MeSH
• sekundární struktura proteinů MeSH
• sekvenční analýza proteinů MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Alveolar rhabdomyosarcoma (aRMS) with lymph node involvement (N1 classification) accounts for up to 10% of all cases of RMS. The prognosis is poor, and is comparable to that of distant metastatic disease. In the European Paediatric Soft Tissue Sarcoma Study Group (EpSSG) RMS2005 protocol, patients with a histologic diagnosis of aRMS/N1 received intensified chemotherapy with systematic locoregional treatment. METHODS: Patients with aRMS/N1 were enrolled prospectively after primary surgery/biopsy and fusion status was assessed in tumor samples. All patients received 9 cycles of induction chemotherapy and 6 months of maintenance therapy. Local treatment included radiotherapy to the primary site and lymph nodes with or without secondary surgical resection. RESULTS: A total of 103 patients were enrolled. The clinical characteristics of the patients were predominantly unfavorable: 90% had macroscopic residual disease after initial surgery/biopsy, 63% had locally invasive tumors, 77% had a tumor measuring >5 cm, and 81% had disease at unfavorable sites. Fusion genes involving forkhead box protein O1 (FOXO1) were detected in 56 of 84 patients. Events occurred in 52 patients: 43 developed disease recurrence, 7 had disease that was refractory to treatment, and 2 patients developed second neoplasms. On univariate analysis, unfavorable disease site, tumor invasiveness, Intergroup Rhabdomyosarcoma Study group III, and fusion-positive status correlated with worse prognosis. The 5-year event-free survival rate of patients with fusion-positive tumors was 43% compared with 74% in patients with fusion-negative tumors (P = .01). On multivariate analysis, fusion positivity and tumor invasiveness proved to be unfavorable prognostic markers. CONCLUSIONS: Fusion status and tumor invasiveness appear to have a strong impact on prognosis in patients with aRMS/N1. Fusion status will be used to stratify these patients in the next EpSSG RMS study, and treatment will be intensified in patients with fusion-positive tumors. Cancer 2018. © 2018 American Cancer Society.

• MeSH
• alveolární rhabdomyosarkom farmakoterapie   epidemiologie   genetika   patologie   MeSH
• dítě MeSH
• dospělí MeSH
• forkhead box protein O1 genetika   MeSH
• kojenec MeSH
• lidé MeSH
• lokální recidiva nádoru farmakoterapie   epidemiologie   genetika   patologie   MeSH
• lymfatické metastázy MeSH
• lymfatické uzliny účinky léků   patologie   chirurgie   MeSH
• mladiství MeSH
• mladý dospělý MeSH
• pediatrie MeSH
• předškolní dítě MeSH
• přežití po terapii bez příznaků nemoci MeSH
• prognóza * MeSH
• protokoly antitumorózní kombinované chemoterapie aplikace a dávkování   MeSH
• rizikové faktory MeSH
• staging nádorů MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• kojenec MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Spindle cell lipoma, cellular angiofibroma and mammary myofibroblastoma are mesenchymal tumours that have overlapping morphological and immunophenotypic features. Aberrations in chromosome 13q14 have been identified as a recurrent feature. We report a unique case of a 69-year-old woman who metachronously developed all three tumours. She developed a peri-urethral and a recurrent peri-vaginal cellular angiofibroma at age 54 and 57, respectively, a spindle cell lipoma at age 62 and a mammary myofibroblastoma at age 69. Dual-colour interphase fluorescent in situ hybridisation (FISH) revealed losses of RB1 and FOXO1 (13q14LOH [loss of heterozygosity]) within neoplastic cells. There was also loss of retinoblastoma (Rb) protein expression. To our knowledge, this is the first report of these three tumours arising in the same patient. The genetic link between these tumours supports the hypothesis that they may arise from the same progenitor cells. However, further research is required to elucidate the precise pathogenetic link.

• MeSH
• angiofibrom genetika   patologie   MeSH
• fenotyp MeSH
• forkhead box protein O1 genetika   MeSH
• genetická predispozice k nemoci MeSH
• hybridizace in situ fluorescenční MeSH
• lidé MeSH
• lidské chromozomy, pár 14 * MeSH
• lipom genetika   patologie   MeSH
• nádorové biomarkery genetika   MeSH
• nádory močové trubice genetika   patologie   MeSH
• nádory prsu genetika   patologie   MeSH
• nádory vaginy genetika   patologie   MeSH
• nádory ze svalové tkáně genetika   patologie   MeSH
• sekundární malignity genetika   patologie   MeSH
• senioři MeSH
• ubikvitinligasy genetika   MeSH
• vazebné proteiny retinoblastomu genetika   MeSH
• ztráta heterozygozity * MeSH
• Check Tag
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• kazuistiky MeSH

Biphenotypic sinonasal sarcoma (BSNS) is a recently recognized type of sarcoma arising exclusively in the sinonasal tract displaying unique clinical course, histopathology, and genetics. Due to its rarity, only case series and case reports are available. In order to provide an overview of the current understanding of this disease, we present a comprehensive review of the literature and present three previously unreported cases of BSNS. A total of 55 genetically characterized and 41 cases without molecular data were identified in the literature. Two-thirds of patients were female and the peak incidence was in the fifth decade. Fatal outcome was rare (two cases with intracranial extension) and local recurrence occurred in 31.6%, all occurring within 5 years after initial treatment. Histologically, BSNS is highly cellular in the majority of cases and composed of fascicles of spindle cells, with entrapped hyperplastic surface epithelium being a frequent finding. The immunohistochemical profile is characteristic due to the biphasic nature of this lesion, with shared features of both myogenic and neural origin. Rhabdomyoblastic differentiation is apparent in a subset of cases. The most common genetic event is the PAX3-MAML3 fusion (58.6%) but isolated PAX3 rearrangement (19.2%), absence of rearrangements (9.1%), PAX3-FOXO1 (8.1%), PAX3-NCOA1 (4%), and isolated MAML3 rearrangement (2%) have also been reported. In conclusion, the recognition of BSNS is crucial due to its relatively indolent clinical course. A selected immunohistochemical panel and/or molecular confirmation can be used to aid in appropriate diagnosis and consequently in prognostication and to avoid overtreatment with chemotherapy regimens used in its mimics.

• MeSH
• DNA vazebné proteiny genetika   MeSH
• dospělí MeSH
• fenotyp MeSH
• forkhead box protein O1 genetika   MeSH
• fúze genů MeSH
• fúzní onkogenní proteiny genetika   MeSH
• genová přestavba MeSH
• imunohistochemie MeSH
• jaderné proteiny genetika   MeSH
• koaktivátor 1 jaderných receptorů genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádorové biomarkery genetika   MeSH
• nádory vedlejších dutin nosních diagnóza   genetika   patologie   MeSH
• prognóza MeSH
• sarkom diagnóza   genetika   patologie   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• transkripční faktor PAX3 genetika   MeSH
• transkripční faktory paired box genetika   MeSH
• transkripční faktory genetika   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• přehledy MeSH

Hromadění lipidů v makrofázích hraje velmi významnou roli v rozvoji aterosklerózy. Proto postupy omezující tuto akumulaci mohou mít velký význam nejen v prevenci kardiovaskulárních komplikací, ale i v jejich léčbě. Z minulosti je známo, že právě antidiabetikum metformin tento proces omezuje; nicméně jeho přesný mechanismus zůstával doposud neobjasněn. Teprve velmi nedávno se ukázalo, že metformin potlačuje expresivitu vazebného proteinu pro mastné kyseliny 4 (FABP4) prostřednictvím inhibice faktoru FOXO1. Díky těmto vlastnostem lze na metformin nahlížet jako na látku, kterou je možné s výhodou použít v prevenci i léčbě aterosklerózy u pacientů s metabolickým syndromem.

• Publikační typ
• zprávy MeSH