pathway complexity
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The p16Ink4/MTS1/CDKN2 is a cell-cycle regulatory inhibitor of cyclin-dependent kinase 4 (cdk4), and a candidate tumour suppressor whose gene on chromosome band 9p21 is frequently deleted or mutated in diverse types of cancer. Cdk4 in association with its D-type cyclin partners, together with p16Ink4, and the product of the retinoblastoma tumour-suppressor gene (pRB), appear to constitute a G1-phase-controlling pathway which can become de-regulated through oncogenic aberrations of any of the components. In an attempt to elucidate the underlying molecular mechanisms, we have now surveyed expression of p16Ink4, at the protein and the mRNA levels, in 21 human cell types expressing normal pRB, as compared with another series of 21 cell lines whose pRB is mutant and/or inactivated through sequestration by DNA tumour virus onco-proteins. In contrast to aberrant lack of p16 expression in the majority of RB-positive cell types, expression of apparently normal (as shown by electrophoretic mobility and/or the ability to form protein-protein complexes with cdk4 in vivo) p16 was uniformly preserved in the cancer cell lines whose RB function was compromised. These data indicate that p16 operates upstream of pRB along the same pathway in G1. The results are discussed in view of the nature of a selective growth advantage potentially gained by cells through de-regulation of this key cell-cycle control mechanism.
- MeSH
- buněčný cyklus fyziologie MeSH
- chromozomální aberace * MeSH
- cyklin-dependentní kinasa 4 MeSH
- cyklin-dependentní kinasy * MeSH
- geny retinoblastomu * MeSH
- inhibitor p16 cyklin-dependentní kinasy MeSH
- inhibitory proteinkinas MeSH
- lidé MeSH
- messenger RNA analýza genetika MeSH
- mutace MeSH
- nádorové buňky kultivované MeSH
- nádory * genetika MeSH
- polymerázová řetězová reakce MeSH
- protein-serin-threoninkinasy antagonisté a inhibitory MeSH
- protoonkogenní proteiny * MeSH
- transportní proteiny * genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
BACKGROUND: The study of the mechanisms controlling wound healing is an attractive area within the field of biology, with it having a potentially significant impact on the health sector given the current medical burden associated with healing in the elderly population. Healing is a complex process and includes many steps that are regulated by coding and noncoding RNAs, proteins and other molecules. Nitric oxide (NO) is one of these small molecule regulators and its function has already been associated with inflammation and angiogenesis during adult healing. RESULTS: Our results showed that NO is also an essential component during embryonic scarless healing and acts via a previously unknown mechanism. NO is mainly produced during the early phase of healing and it is crucial for the expression of genes associated with healing. However, we also observed a late phase of healing, which occurs for several hours after wound closure and takes place under the epidermis and includes tissue remodelling that is dependent on NO. We also found that the NO is associated with multiple cellular metabolic pathways, in particularly the glucose metabolism pathway. This is particular noteworthy as the use of NO donors have already been found to be beneficial for the treatment of chronic healing defects (including those associated with diabetes) and it is possible that its mechanism of action follows those observed during embryonic wound healing. CONCLUSIONS: Our study describes a new role of NO during healing, which may potentially translate to improved therapeutic treatments, especially for individual suffering with problematic healing.
- MeSH
- embryo nesavčí cytologie metabolismus fyziologie MeSH
- glukosa metabolismus MeSH
- hojení ran * MeSH
- leptin metabolismus MeSH
- oxid dusnatý metabolismus MeSH
- regulace genové exprese MeSH
- signální transdukce MeSH
- Xenopus laevis MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The field of Neurochemistry spent decades trying to understand how the brain works, from nano to macroscale and across diverse species. Technological advancements over the years allowed researchers to better visualize and understand the cellular processes underpinning central nervous system (CNS) function. This review provides an overview of how novel models, and tools have allowed Neurochemistry researchers to investigate new and exciting research questions. We discuss the merits and demerits of different in vivo models (e.g., Caenorhabditis elegans, Drosophila melanogaster, Ratus norvegicus, and Mus musculus) as well as in vitro models (e.g., primary cells, induced pluripotent stem cells, and immortalized cells) to study Neurochemical events. We also discuss how these models can be paired with cutting-edge genetic manipulation (e.g., CRISPR-Cas9 and engineered viral vectors) and imaging techniques, such as super-resolution microscopy and new biosensors, to study cellular processes of the CNS. These technological advancements provide new insight into Neurochemical events in physiological and pathological contexts, paving the way for the development of new treatments (e.g., cell and gene therapies or small molecules) that aim to treat neurological disorders by reverting the CNS to its homeostatic state.
Extracorporeal membrane oxygenation (ECMO) has been used increasingly for both respiratory and cardiac failure in adult patients. Indications for ECMO use in cardiac failure include severe refractory cardiogenic shock, refractory ventricular arrhythmia, active cardiopulmonary resuscitation for cardiac arrest, and acute or decompensated right heart failure. Evidence is emerging to guide the use of this therapy for some of these indications, but there remains a need for additional evidence to guide best practices. As a result, the use of ECMO may vary widely across centers. The purpose of this document is to highlight key aspects of care delivery, with the goal of codifying the current use of this rapidly growing technology. A major challenge in this field is the need to emergently deploy ECMO for cardiac failure, often with limited time to assess the appropriateness of patients for the intervention. For this reason, we advocate for a multidisciplinary team of experts to guide institutional use of this therapy and the care of patients receiving it. Rigorous patient selection and careful attention to potential complications are key factors in optimizing patient outcomes. Seamless patient transport and clearly defined pathways for transition of care to centers capable of providing heart replacement therapies (e.g., durable ventricular assist device or heart transplantation) are essential to providing the highest level of care for those patients stabilized by ECMO but unable to be weaned from the device. Ultimately, concentration of the most complex care at high-volume centers with advanced cardiac capabilities may be a way to significantly improve the care of this patient population.
- MeSH
- dospělí MeSH
- kardiogenní šok * MeSH
- lidé MeSH
- mimotělní membránová oxygenace * MeSH
- podpůrné srdeční systémy MeSH
- srdeční selhání * terapie MeSH
- transplantace srdce MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: To assess the potential of second-generation proteasome inhibition by carfilzomib and its combination with the human immunodeficiency virus (HIV) protease inhibitors (HIV-PIs) lopinavir and nelfinavir in vitro for improved treatment of clear cell renal cell cancer (ccRCC). MATERIALS AND METHODS: Cytotoxicity, reactive oxygen species (ROS) production, and unfolded protein response (UPR) activation of proteasome inhibitors, HIV-PIs, and their combination were assessed in three cell lines and primary cells derived from three ccRCC tumours by MTS assay, flow cytometry, quantitative reverse transcriptase-polymerase chain reaction and western blot, respectively. Proteasome activity was determined by activity based probes. Flow cytometry was used to assess apoptosis by annexin V/propidium iodide assay and ATP-binding cassette sub-family B member 1 (ABCB1) activity by MitoTrackerTM Green FM efflux assay (Thermo Fisher Scientific, MA, USA). RESULTS: Lopinavir and nelfinavir significantly increased the cytotoxic effect of carfilzomib in all cell lines and primary cells. ABCB1 efflux pump inhibition, induction of ROS production, and UPR pre-activation by lopinavir were identified as underlying mechanisms of this strong synergistic effect. Combined treatment led to unresolved protein stress, increased activation of pro-apoptotic UPR pathway, and a significant increase in apoptosis. CONCLUSION: The combination of the proteasome inhibitor carfilzomib and the HIV-PIs lopinavir and nelfinavir has a strong synergistic cytotoxic activity against ccRCCin vitro at therapeutically relevant drug concentrations. This effect is most likely explained by synergistic UPR triggering and ABCB1-modulation caused by HIV-PIs. Our findings suggest that combined treatment of second-generation proteasome inhibitors and HIV-PIs should be investigated in patients with metastatic RCC within a clinical trial.
- MeSH
- chemorezistence MeSH
- inhibitory HIV-proteasy terapeutické užití MeSH
- inhibitory proteasomu terapeutické užití MeSH
- karcinom z renálních buněk farmakoterapie MeSH
- lidé MeSH
- Lopinavir terapeutické užití MeSH
- nádorové buněčné linie MeSH
- nádory ledvin farmakoterapie MeSH
- nelfinavir terapeutické užití MeSH
- protinádorové látky terapeutické užití MeSH
- stres endoplazmatického retikula účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Východiska: Nejnovější výzkumy týkající se podílu microRNA (miRNA) na nádorové angiogenezi a onkogenních účinků miRNA ukazují na jejich potenciální roli při angiogenezi karcinomu prsu. Exozomy získané z nádoru jsou považovány za bohatý zdroj miRNA, které regulují funkce ostatních buněk v nádorovém mikroprostředí, vč. endoteliálních buněk cév. Tato studie analyzuje účinek chemoterapie tamoxifenem na expresi klíčové miRNA, miR-573, která se účastní angiogeneze v exozomech nádoru a působí jako regulační spojka mezi miRNA a genem CD146, který je součástí dráhy vaskulárního endoteliálního růstového faktoru (vascular endothelial growth factor – VEGF). Materiál a metody: Byly zakoupeny buňky karcinomu prsu MCF-7 a kultivovány v kompletním médiu. Tyto buňky byly ošetřeny tamoxifenem a z média byly následně exrahovány jejich exozomy. Byla izolována RNA exozomů a pomocí metody polymerázové řetězové reakce (PCR) v reálném čase byla vyhodnocena exprese genů miR-573, VEGF a CD146 v exozomech. Výsledky: Výsledky této studie ukázaly, že ošeření buněk tamoxifenem zvýšilo expresi miR-573 v exozomech získaných z nádorových buněk MCF-7. Exprese genů CD146 a VEGF v exozomech buněk ošetřených léčivem měla klesající tendenci. Závěr: Výsledky tohoto pokusu prokázaly, že ošetření nádorových buněk tamoxifenem snižuje expresi genů VEGF and CD146 zvýšením miR-573. Dochází tedy k omezení angiogeneze a tím k protinádorovému působení léčiva.
Background: Recent developments regarding the contribution of microRNAs (miRNAs) to tumor angiogenesis and the oncogenic effects of miRNAs point to their potential role in breast cancer angiogenesis. Tumor-derived exosomes are considered a rich source of miRNAs that can regulate the function of other cells in the tumor microenvironment, including vascular endothelial cells. This study analyzes the effect of tamoxifen chemotherapy on the expression of a key miRNA, miR-573, involved in the angiogenesis of the tumor exosomes and introduces a regulatory link between this miRNA and the CD146 gene associated with the vascular endothelial growth factor (VEGF) messaging pathway. Materials and methods: MCF-7 breast cancer cells were purchased and cultured in a complete culture medium. These cells were treated with tamoxifen and then their exosomes were extracted from the culture medium. The RNAs of the exosomes were isolated and the expression of miR-573, VEGF, and CD146 genes in the exosomes was investigated using the real-time polymerase chain reaction (PCR) method. Results: The results of this study showed that tamoxifen treatment increased the expression of miR-573 in exosomes derived from MCF-7 cancer cells. The expression of CD146 and VEGF genes in drug-treated cell exosomes had a downward pattern. Conclusion: The results of this experiment demonstrated that the treatment of breast cancer cells with tamoxifen reduces the expression of VEGF and CD146 by increasing miR-573. Thus, angiogenesis is reduced and, therefore, its anti-tumor effects are applied.
- Klíčová slova
- miR-573,
- MeSH
- exozom terapeutické užití účinky léků MeSH
- lidé MeSH
- MFC-7 buňky patologie MeSH
- mikro RNA analýza genetika účinky léků MeSH
- nádorové buňky kultivované účinky léků MeSH
- nádory prsu * farmakoterapie genetika patologie MeSH
- patologická angiogeneze etiologie genetika prevence a kontrola MeSH
- tamoxifen * analýza aplikace a dávkování farmakologie terapeutické užití MeSH
- vaskulární endoteliální růstové faktory genetika účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- klinická studie MeSH
- práce podpořená grantem MeSH
Long-lasting ischemia can result in cell loss; however, repeated episodes of brief ischemia increase the resistance of the heart against deleterious effects of subsequent prolonged ischemic insult and promote cell survival. Traditionally, it is believed that the supply of blood to the ischemic heart is associated with release of cytokines, activation of inflammatory response, and induction of necrotic cell death. In the past few years, this paradigm of passive necrosis as an uncontrolled cell death has been re-examined and the existence of a strictly regulated form of necrotic cell death, necroptosis, has been documented. This controlled cell death modality, resembling all morphological features of necrosis, has been investigated in different types of ischemia-associated heart injuries. The process of necroptosis has been found to be dependent on the activation of RIP1-RIP3-MLKL axis, which induces changes leading to the rupture of cell membrane. This pathway is activated by TNF-α, which has also been implicated in the cardioprotective signaling pathway of ischemic preconditioning. Thus, this review is intended to describe the TNF-α-mediated signaling leading to either cell survival or necroptotic cell death. In addition, some experimental data suggesting a link between heart dysfunction and the cellular loss due to necroptosis are discussed in various conditions of myocardial ischemia.
- MeSH
- apoptóza * účinky léků MeSH
- ischemická choroba srdeční metabolismus patologie MeSH
- komplex proteinů jaderného póru metabolismus MeSH
- lidé MeSH
- myokard metabolismus patologie MeSH
- nekróza MeSH
- proteinkinasy metabolismus MeSH
- proteiny vázající RNA metabolismus MeSH
- serin-threoninkinasy interagující s receptory metabolismus MeSH
- signální transdukce MeSH
- TNF-alfa metabolismus MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Microcystins (MCs) are primarily hepatotoxins produced by cyanobacteria and are responsible for intoxication in humans and animals. There are many incidents of chronic exposure to MCs, which have been attributed to the inappropriate treatment of water supplies or contaminated food. Using RAW 264.7 macrophages, we showed the potency of microcystin-LR (MC-LR) to stimulate production of pro-inflammatory cytokines (tumor necrosis factor α and interleukin-6) as a consequence of fast nuclear factor κB and nitrogen-activated protein kinase activation. In contrast to other studies, the observed effects were not attributed to the intracellular inhibition of protein phosphatases 1/2A due to lack of specific transmembrane transporters for MCs. However, the MC-LR-induced activation of macrophages was effectively inhibited by a specific peptide that blocks signaling of receptors, which play a pivotal role in the innate immune responses. Taken together, we showed for the first time that MC-LR could interfere with macrophage receptors that are responsible for triggering the above-mentioned signaling pathways. These findings provide an interesting mechanistic explanation of some adverse health outcomes associated with toxic cyanobacteria and MCs.
- MeSH
- buněčné linie účinky léků MeSH
- chemické látky znečišťující vodu toxicita MeSH
- imunologické faktory toxicita MeSH
- interleukin-6 metabolismus MeSH
- makrofágy účinky léků metabolismus patologie MeSH
- mikrocystiny toxicita MeSH
- myši MeSH
- NF-kappa B metabolismus MeSH
- přirozená imunita účinky léků MeSH
- proteinfosfatasa 2 metabolismus MeSH
- sinice patogenita MeSH
- testy chronické toxicity metody MeSH
- TNF-alfa metabolismus MeSH
- zánět chemicky indukované imunologie metabolismus MeSH
- zásobování vodou MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Undifferentiated (anaplastic) and rhabdoid cell features are increasingly recognized as adverse prognostic findings in renal cell carcinoma (RCC), but their molecular pathogenesis has not been studied sufficiently. Recent studies identified alterations in the Switch Sucrose nonfermentable (SWI/SNF) chromatin remodeling complex as molecular mechanisms underlying dedifferentiation and rhabdoid features in carcinomas of different organs. We herein have analyzed 32 undifferentiated RCCs having in common an undifferentiated (anaplastic) phenotype, prominent rhabdoid features, or both, irrespective of the presence or absence of conventional RCC component. Cases were stained with 6 SWI/SNF pathway members (SMARCB1, SMARCA2, SMARCA4, ARID1A, SMARCC1, and SMARCC2) in addition to conventional RCC markers. Patients were 20 males and 12 females aged 32 to 85 years (mean, 59). A total of 22/27 patients with known stage presented with ≥pT3. A differentiated component varying from microscopic to major component was detected in 20/32 cases (16 clear cell and 2 cases each chromophobe and papillary RCC). The undifferentiated component varied from rhabdoid dyscohesive cells to large epithelioid to small monotonous anaplastic cells. Variable loss of at least 1 SWI/SNF complex subunit was noted in the undifferentiated/rhabdoid component of 21/32 cases (65%) compared with intact or reduced expression in the differentiated component. A total of 15/17 patients (88%) with follow-up died of metastatic disease (mostly within 1 y). Only 2 patients were disease free at last follow-up (1 and 6 y). No difference in survival, age distribution, or sex was observed between the SWI/SNF-deficient and the SWI/SNF-intact group. This is the first study exploring the role of SWI/SNF deficiency as a potential mechanism underlying undifferentiated and rhabdoid phenotype in RCC. Our results highlight the association between the aggressive rhabdoid phenotype and the SWI/SNF complex deficiency, consistent with studies on similar neoplasms in other organs. Thorough sampling of such tumors that are usually huge and locally advanced is necessary for recognizing the clone of origin and hence for proper subtyping and also for differentiating them from undifferentiated urothelial carcinoma.
- MeSH
- dediferenciace buněk MeSH
- DNA-helikasy analýza metabolismus MeSH
- dospělí MeSH
- fenotyp MeSH
- imunohistochemie MeSH
- jaderné proteiny analýza metabolismus MeSH
- karcinom z renálních buněk patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory ledvin patologie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- transkripční faktory analýza metabolismus 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
Undifferentiated gastrointestinal tract carcinomas are rare highly aggressive neoplasms with frequent but not obligatory rhabdoid features. Recent studies showed loss of SMARCB1 (INI1), a core subunit of the SWI/SNF chromatin remodeling complex, in 50% of tested cases. However, the molecular pathways underlying histologically similar but SMARCB1-intact cases are unknown. We herein analyzed 13 cases for expression of 4 SWI/SNF complex subunits SMARCB1, SMARCA2, SMARCA4, and ARID1A and the mismatch-repair proteins MLH1, MSH2, MSH6, and PMS2 by immunohistochemistry. Patients included 12 men and 1 woman aged 32 to 81 years (median, 57 y). Site of origin was colon (5), small bowel (2), stomach (3), small+large intestine (1), small intestine+ampulla of Vater (1), and esophagogastric junction (1). All tumors showed anaplastic large to medium-sized cells with variable rhabdoid features, pleomorphic giant cells, and, rarely, spindle cell foci. Abortive gland formation was seen in 3 cases and bona fide glandular component in 1 case. Most cases strongly expressed vimentin and variably pancytokeratin. In total, 12/13 cases (92%) showed loss of at least 1 SWI/SNF component. Loss of SMARCB1 (5/13), SMARCA2 (10/13), SMARCA4 (2/13), and ARID1A (2/13) was observed either in combination or isolated. SMARCA2 loss was isolated in 5 cases and coexisted with lost SMARCB1 in 5 cases (all 5 SMARCB1-deficient tumors showed loss of SMARCA2 as well). Co-inactivation of SMARCB1 and SMARCA4 or of SMARCA2 and SMARCA4 was not observed. Two mismatch-repair-deficient cases (MLH1/PMS2) showed concurrent loss of SMARCB1, SMARCA2, and (one of them) ARID1A. This study illustrates for the first time loss of different components of the SWI/SNF complex other than SMARCB1 in undifferentiated gastrointestinal carcinomas including novel SMARCA4-deficient and SMARCA2-deficient cases. Our results underline the close link between SWI/SNF deficiency and the aggressive rhabdoid phenotype. Frequent loss of SMARCA2 possibly points to fragility/vulnerability of the SWI/SNF complex as a consequence of lost core subunit SMARCB1. The exact molecular mechanisms underlying co-inactivation of different SWI/SNF subunits merit further investigations.
- MeSH
- chromozomální proteiny, nehistonové genetika MeSH
- dědičné nádorové syndromy MeSH
- DNA-helikasy genetika MeSH
- dospělí MeSH
- gastrointestinální nádory genetika patologie MeSH
- imunohistochemie MeSH
- jaderné proteiny genetika MeSH
- karcinom genetika patologie MeSH
- kolorektální nádory MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory mozku MeSH
- senioři nad 80 let MeSH
- senioři 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