Prostate cancer (PCa) is the second leading cause of cancer-related deaths in men in Western countries, and there is still an urgent need for a better understanding of PCa progression to inspire new treatment strategies. Skp2 is a substrate-recruiting component of the E3 ubiquitin ligase complex, whose activity is regulated through neddylation. Slug is a transcriptional repressor involved in the epithelial-to-mesenchymal transition, which may contribute to therapy resistance. Although Skp2 has previously been associated with a mesenchymal phenotype and prostate cancer progression, the relationship with Slug deserves further elucidation. We have previously shown that a high Gleason score (≥8) is associated with higher Skp2 and lower E-cadherin expression. In this study, significantly increased expression of Skp2, AR, and Slug, along with E-cadherin downregulation, was observed in primary prostate cancer in patients who already had lymph node metastases. Skp2 was slightly correlated with Slug and AR in the whole cohort (Rs 0.32 and 0.37, respectively), which was enhanced for both proteins in patients with high Gleason scores (Rs 0.56 and 0.53, respectively) and, in the case of Slug, also in patients with metastasis to lymph nodes (Rs 0.56). Coexpression of Skp2 and Slug was confirmed in prostate cancer tissues by multiplex immunohistochemistry and confocal microscopy. The same relationship between these two proteins was observed in three sets of prostate epithelial cell lines (PC3, DU145, and E2) and their mesenchymal counterparts. Chemical inhibition of Skp2, but not RNA interference, modestly decreased Slug protein in PC3 and its docetaxel-resistant subline PC3 DR12. Importantly, chemical inhibition of Skp2 by MLN4924 upregulated p27 and decreased Slug expression in PC3, PC3 DR12, and LAPC4 cells. Novel treatment strategies targeting Skp2 and Slug by the neddylation blockade may be promising in advanced prostate cancer, as recently documented for other aggressive solid tumors.

• Klíčová slova
• Skp2 (S-phase kinase-associated protein 2), Slug, immunohistochemistry, multiplex, neddylation, prostate cancer,
• MeSH
• androgenní receptory genetika   metabolismus   MeSH
• buňky PC-3 MeSH
• CD antigeny genetika   metabolismus   MeSH
• cyklopentany farmakologie   MeSH
• docetaxel farmakologie   MeSH
• epitelo-mezenchymální tranzice genetika   MeSH
• inhibitor p27 cyklin-dependentní kinasy genetika   metabolismus   MeSH
• kadheriny genetika   metabolismus   MeSH
• lidé MeSH
• lymfatické metastázy MeSH
• malá interferující RNA genetika   metabolismus   MeSH
• nádorové buněčné linie MeSH
• nádory prostaty genetika   metabolismus   patologie   MeSH
• posttranslační úpravy proteinů * MeSH
• prostata metabolismus   patologie   MeSH
• protein NEDD8 genetika   metabolismus   MeSH
• proteiny asociované s kinázou S-fáze antagonisté a inhibitory   genetika   metabolismus   MeSH
• protinádorové látky farmakologie   MeSH
• pyrimidiny farmakologie   MeSH
• regulace genové exprese u nádorů MeSH
• rodina transkripčních faktorů Snail genetika   metabolismus   MeSH
• stupeň nádoru MeSH
• viabilita buněk účinky léků   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• androgenní receptory MeSH
• CD antigeny MeSH
• CDH1 protein, human MeSH Prohlížeč
• cyklopentany MeSH
• docetaxel MeSH
• inhibitor p27 cyklin-dependentní kinasy MeSH
• kadheriny MeSH
• malá interferující RNA MeSH
• NEDD8 protein, human MeSH Prohlížeč
• pevonedistat MeSH Prohlížeč
• protein NEDD8 MeSH
• proteiny asociované s kinázou S-fáze MeSH
• protinádorové látky MeSH
• pyrimidiny MeSH
• rodina transkripčních faktorů Snail MeSH
• SKP2 protein, human MeSH Prohlížeč
• SNAI1 protein, human MeSH Prohlížeč

Although the induction of senescence in cancer cells is a potent mechanism of tumor suppression, senescent cells remain metabolically active and may secrete a broad spectrum of factors that promote tumorigenicity in neighboring malignant cells. Here we show that androgen deprivation therapy (ADT), a widely used treatment for advanced prostate cancer, induces a senescence-associated secretory phenotype in prostate cancer epithelial cells, indicated by increases in senescence-associated β-galactosidase activity, heterochromatin protein 1β foci, and expression of cathepsin B and insulin-like growth factor binding protein 3. Interestingly, ADT also induced high levels of vimentin expression in prostate cancer cell lines in vitro and in human prostate tumors in vivo. The induction of the senescence-associated secretory phenotype by androgen depletion was mediated, at least in part, by down-regulation of S-phase kinase-associated protein 2, whereas the neuroendocrine differentiation of prostate cancer cells was under separate control. These data demonstrate a previously unrecognized link between inhibition of androgen receptor signaling, down-regulation of S-phase kinase-associated protein 2, and the appearance of secretory, tumor-promoting senescent cells in prostate tumors. We propose that ADT may contribute to the development of androgen-independent prostate cancer through modulation of the tissue microenvironment by senescent cells.

• MeSH
• androgenní receptory metabolismus   MeSH
• antagonisté androgenů farmakologie   MeSH
• beta-galaktosidasa metabolismus   MeSH
• down regulace účinky léků   MeSH
• fosfohydroláza PTEN metabolismus   MeSH
• IGFBP-3 metabolismus   MeSH
• kathepsin B metabolismus   MeSH
• konfokální mikroskopie MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádory prostaty genetika   metabolismus   patologie   MeSH
• proteiny asociované s kinázou S-fáze genetika   metabolismus   MeSH
• průtoková cytometrie MeSH
• RNA interference MeSH
• signální transdukce účinky léků   MeSH
• stárnutí buněk účinky léků   MeSH
• vimentin metabolismus   MeSH
• western blotting MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• androgenní receptory MeSH
• antagonisté androgenů MeSH
• AR protein, human MeSH Prohlížeč
• beta-galaktosidasa MeSH
• fosfohydroláza PTEN MeSH
• IGFBP-3 MeSH
• kathepsin B MeSH
• proteiny asociované s kinázou S-fáze MeSH
• vimentin MeSH

DNA lesions trigger the DNA damage response (DDR) machinery, which protects genomic integrity and sustains cellular survival. Increasing data underline the significance of the integrity of the DDR pathway in chemotherapy response. According to a recent work, persistent exposure of A549 lung carcinoma cells to doxorubicin induces an initial DDR-dependent checkpoint response, followed by a later DDR-independent, but p27(Kip1)-dependent one. Prompted by the above report and to better understand the involvement of the DDR signaling after chemotherapeutic stress, we examined the potential role of the canonical DDR pathway in A549 cells treated with doxorubicin. Exposure of A549 cells, prior to doxorubicin treatment, to ATM, ATR and DNA-PKcs inhibitors either alone or in various combinations, revealed that the earlier documented two-step response was DDR-dependent in both steps. Notably, inhibition of both ATM and ATR or selective inhibition of ATM or DNA-PKcs resulted in cell-cycle re-entry despite the increased levels of p27(Kip1) at all time points analyzed. We further investigated the regulation of p27(Kip1) protein levels in the particular setting. Our results showed that the protein status of p27(Kip1) is mainly determined by p38-MAPK, whereas the role of SKP2 is less significant in the doxoroubicin-treated A549 cells. Cumulatively, we provide evidence that the DNA damage signaling is responsible for the prolonged cell cycle arrest observed after persistent chemotherapy-induced genotoxic stress. In conclusion, precise identification of the molecular mechanisms that are activated during the chemotherapeutic cycles could potentially increase the sensitization to the therapy applied.

• Klíčová slova
• ATM, ATR, DNA damage response, DNA-PKcs, SKP2, cell cycle arrest, chemotherapy, p27Kip1, p38-MAPK,
• MeSH
• ATM protein antagonisté a inhibitory   MeSH
• buňky A549 MeSH
• chromony farmakologie   MeSH
• doxorubicin farmakologie   MeSH
• inhibitor p27 cyklin-dependentní kinasy fyziologie   MeSH
• kofein farmakologie   MeSH
• kontrolní body fáze G2 buněčného cyklu účinky léků   MeSH
• lidé MeSH
• mitogenem aktivované proteinkinasy p38 metabolismus   MeSH
• morfoliny farmakologie   MeSH
• poškození DNA MeSH
• proteinkinasa aktivovaná DNA antagonisté a inhibitory   MeSH
• proteiny asociované s kinázou S-fáze metabolismus   MeSH
• protinádorové látky farmakologie   MeSH
• pyrony farmakologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 2-morpholin-4-yl-6-thianthren-1-yl-pyran-4-one MeSH Prohlížeč
• 8-dibenzothiophen-4-yl-2-morpholin-4-yl-chromen-4-one MeSH Prohlížeč
• ATM protein, human MeSH Prohlížeč
• ATM protein MeSH
• CDKN1B protein, human MeSH Prohlížeč
• chromony MeSH
• doxorubicin MeSH
• inhibitor p27 cyklin-dependentní kinasy MeSH
• kofein MeSH
• mitogenem aktivované proteinkinasy p38 MeSH
• morfoliny MeSH
• proteinkinasa aktivovaná DNA MeSH
• proteiny asociované s kinázou S-fáze MeSH
• protinádorové látky MeSH
• pyrony MeSH

SummaryWe report here the existence of bands of higher molecular weight after western blot analysis in three proteins - Skp1, p27 and IκBα in bovine preimplantation embryos. This finding is specific to preimplantation embryos (from the 2-cell stage to the blastocyst stage) and not differentiated fibroblast cells in which these bands were of expected molecular weight. We suggest that these bands of higher molecular weight represent a complex of proteins that are characteristic of preimplantation embryos.

• Klíčová slova
• IκBα, Molecular weight, Preimplantation embryo, Skp1, p27,
• MeSH
• blastocysta cytologie   metabolismus   MeSH
• embryonální vývoj * MeSH
• inhibitor p27 cyklin-dependentní kinasy chemie   metabolismus   MeSH
• molekulová hmotnost MeSH
• NFKB inhibitor alfa chemie   metabolismus   MeSH
• proteiny asociované s kinázou S-fáze chemie   metabolismus   MeSH
• proteiny chemie   metabolismus   MeSH
• skot MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• skot MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• inhibitor p27 cyklin-dependentní kinasy MeSH
• NFKB inhibitor alfa MeSH
• proteiny asociované s kinázou S-fáze MeSH
• proteiny MeSH

The plant hormone auxin is a key regulator of plant growth and development. Differences in auxin distribution within tissues are mediated by the polar auxin transport machinery, and cellular auxin responses occur depending on changes in cellular auxin levels. Multiple receptor systems at the cell surface and in the interior operate to sense and interpret fluctuations in auxin distribution that occur during plant development. Until now, three proteins or protein complexes that can bind auxin have been identified. SCF(TIR1) [a SKP1-cullin-1-F-box complex that contains transport inhibitor response 1 (TIR1) as the F-box protein] and S-phase-kinase-associated protein 2 (SKP2) localize to the nucleus, whereas auxin-binding protein 1 (ABP1), predominantly associates with the endoplasmic reticulum and cell surface. In this Cell Science at a Glance article, we summarize recent discoveries in the field of auxin transport and signaling that have led to the identification of new components of these pathways, as well as their mutual interaction.

• Klíčová slova
• Auxin, Signaling, Transporters,
• MeSH
• aktivní transport fyziologie   MeSH
• Arabidopsis genetika   metabolismus   MeSH
• F-box proteiny genetika   metabolismus   MeSH
• kyseliny indoloctové metabolismus   MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• receptory buněčného povrchu genetika   metabolismus   MeSH
• transportní proteiny genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• F-box proteiny MeSH
• kyseliny indoloctové MeSH
• proteiny huseníčku MeSH
• receptory buněčného povrchu MeSH
• SKP2A protein, Arabidopsis MeSH Prohlížeč
• TIR1 protein, Arabidopsis MeSH Prohlížeč
• transportní proteiny MeSH

Cellular and molecular pathways link thrombosis and innate immune system during sepsis. Extrinsic pathway activation of protease thrombin through FVIIa and tissue factor (TF) in sepsis help activate its endothelial cell (EC) membrane Protease Activated Receptor 1 (PAR-1). Thrombin adjusts the EC cycle through activation of G proteins (G12/13), and later through Rho GEFs (guanine nucleotide exchange factors), and provides a path for Rho GTPases mediated cytoskeletal responses involved in shape change and permeability of the EC membrane leading to an increase of leakage of plasma proteins.At the same time, thrombin stimulates spontaneous mitogenesis by inducing activation of the cell cycle from G0-G1 to S by down-regulation of p27Kip1, a negative regulator of the cell cycle, in association with the up-regulation of S-phase kinase associated protein 2 (Skp2). After transport in cytoplasm, p27 Kip1 binds to RhoA thus prevent activation of RhoA by GEFs, thus inhibit GDP-GTP exchange mediated by GEFs. In cytoplasm, releasing factor (RF) p27-RF-Rho is able to free RhoA. P27 RF-Rho binds p27kip1 and prevents p27kip1 from binding to RhoA. Exposed RhoA is later able to increase the expression of the F-box protein Skp2, after its Akt triggered 14-3-3-β-dependent cytoplasm relocation. Skp2 increases cytoplasm ubiquitination-dependent degradation of p27Kip1. Additionally, after septic induction of canonical NF-kB pathway in EC through TLR4/IRAK4/TRAF/IkB, an IKKα dimer phosphorylates the p52 precursor NF-kB2/p100, leading to p100 processing and translocation of RelB/p52 to the nucleus. By controlling the NF-kB-RelB complex, IKKα signaling regulates the transcription of the Skp2 and correspondingly p27Kip1.

• Klíčová slova
• Cell Cycle, Inherited Immune System, PAR, TLR, Thrombin,
• Publikační typ
• časopisecké články MeSH