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To accelerate the impact of African genomics on human health, data science skills and awareness of Africa's rich genetic diversity must be strengthened globally. We describe the first African genomics data science workshop, implemented by the African Society of Human Genetics (AfSHG) and international partners, providing a framework for future workshops.
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Ciência de Dados , Genômica , Humanos , Genética HumanaRESUMO
Tumour cells endure both oncogenic and environmental stresses during cancer progression. Transformed cells must meet increased demands for protein and lipid production needed for rapid proliferation and must adapt to exist in an oxygen- and nutrient-deprived environment. To overcome such challenges, cancer cells exploit intrinsic adaptive mechanisms such as the unfolded protein response (UPR). The UPR is a pro-survival mechanism triggered by accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER), a condition referred to as ER stress. IRE1, PERK and ATF6 are three ER anchored transmembrane receptors. Upon induction of ER stress, they signal in a coordinated fashion to re-establish ER homoeostasis, thus aiding cell survival. Over the past decade, evidence has emerged supporting a role for the UPR in the establishment and progression of several cancers, including breast cancer, prostate cancer and glioblastoma multiforme. This review discusses our current knowledge of the UPR during oncogenesis, tumour growth, metastasis and chemoresistance.
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Carcinogênese/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Animais , Retículo Endoplasmático/metabolismo , Humanos , Proteínas Serina-Treonina Quinases/metabolismoRESUMO
Cancer cells are exposed to intrinsic (oncogene) or extrinsic (microenvironmental) challenges, leading to activation of stress response pathways. The unfolded protein response (UPR) is the cellular response to endoplasmic reticulum (ER) stress and plays a pivotal role in tumor development. Depending on ER stress intensity and duration, the UPR is either pro-survival to preserve ER homeostasis or pro-death if the stress cannot be resolved. On one hand, the adaptive arm of the UPR is essential for cancer cells to survive the harsh conditions they are facing, and on the other hand, cancer cells have evolved mechanisms to bypass ER stress-induced cell death, thereby conferring them with a selective advantage for malignant transformation. Therefore, the mechanisms involved in the balance between survival and death outcomes of the UPR may be exploited as therapeutic tools to treat cancer.
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Apoptose , Neoplasias/metabolismo , Neoplasias/patologia , Resposta a Proteínas não Dobradas , Fator 6 Ativador da Transcrição/metabolismo , Trifosfato de Adenosina/química , Animais , Linhagem da Célula , Sobrevivência Celular , Transformação Celular Neoplásica , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Endorribonucleases/metabolismo , Homeostase , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de SinaisRESUMO
The endoplasmic reticulum (ER) is a highly dynamic organelle of fundamental importance present in all eukaryotic cells. The majority of synthesized structural and secreted proteins undergo post-translational modification, folding and oligomerization in the ER lumen, enabling proteins to carry out their physiological functions. Therefore, maintenance of ER homeostasis and function is imperative for proper cellular function. Physiological and pathological conditions can disturb ER homeostasis and thus negatively impact upon protein folding, resulting in an accumulation of unfolded proteins. Examples include hypoxia, hypo- and hyperglycemia, acidosis, and fluxes in calcium levels. Increased levels of unfolded/misfolded proteins within the ER lumen triggers a condition commonly referred to as 'ER stress'. To combat ER stress, cells have evolved a highly conserved adaptive stress response referred to as the unfolded protein response (UPR). UPR signaling affords the cell a 'window of opportunity' for stress resolution however, if prolonged or excessive the UPR is insufficient and ER stress-induced cell death ensues. This review discusses the role of ER stress sensors IRE1, PERK and ATF6, describing their role in ER stress-induced death signaling with specific emphasis placed upon the importance of the intrinsic cell death pathway and Bcl-2 family regulation.
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Morte Celular/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Animais , Retículo Endoplasmático/metabolismo , HumanosRESUMO
The stimuli for neuronal cell death in neurodegenerative disorders are multi-factorial and may include genetic predisposition, environmental factors, cellular stressors such as oxidative stress and free radical production, bioenergy failure, glutamate-induced excitotoxicity, neuroinflammation, disruption of Ca(2+) -regulating systems, mitochondrial dysfunction and misfolded protein accumulation. Cellular stress disrupts functioning of the endoplasmic reticulum (ER), a critical organelle for protein quality control, leading to induction of the unfolded protein response (UPR). ER stress may contribute to neurodegeneration in a range of neurodegenerative disorders. This review summarizes the molecular events occurring during ER stress and the unfolded protein response and it specifically evaluates the evidence suggesting the ER stress response plays a role in neurodegenerative disorders.
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Estresse do Retículo Endoplasmático , Doenças Neurodegenerativas/metabolismo , Resposta a Proteínas não Dobradas , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Apoptose , Autofagia/genética , Endorribonucleases/genética , Endorribonucleases/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Doenças Neurodegenerativas/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doenças Priônicas/genética , Doenças Priônicas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismoRESUMO
Cdc7 is an essential kinase that promotes DNA replication by activating origins of replication. Here, we characterized the potent Cdc7 inhibitor PHA-767491 (1) in biochemical and cell-based assays, and we tested its antitumor activity in rodents. We found that the compound blocks DNA synthesis and affects the phosphorylation of the replicative DNA helicase at Cdc7-dependent phosphorylation sites. Unlike current DNA synthesis inhibitors, PHA-767491 prevents the activation of replication origins but does not impede replication fork progression, and it does not trigger a sustained DNA damage response. Treatment with PHA-767491 results in apoptotic cell death in multiple cancer cell types and tumor growth inhibition in preclinical cancer models. To our knowledge, PHA-767491 is the first molecule that directly affects the mechanisms controlling initiation as opposed to elongation in DNA replication, and its activities suggest that Cdc7 kinase inhibition could be a new strategy for the development of anticancer therapeutics.
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Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Replicação do DNA/efeitos dos fármacos , DNA/efeitos dos fármacos , Piperidonas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirróis/farmacologia , Animais , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA/biossíntese , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Camundongos Nus , Camundongos SCID , Componente 2 do Complexo de Manutenção de Minicromossomo , Estrutura Molecular , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/química , Fosforilação , Piperidonas/química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Pirróis/química , Ratos , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Genomics is revolutionizing biomedical research, medicine and healthcare globally in academic, public and industry sectors alike. Concrete examples around the world show that huge benefits for patients, society and economy can be accrued through effective and responsible genomic research and clinical applications. Unfortunately, Ireland has fallen behind and needs to act now in order to catch up. Here, we identify key issues that have resulted in Ireland lagging behind, describe how genomics can benefit Ireland and its people and outline the measures needed to make genomics work for Ireland and Irish patients. There is now an urgent need for a national genomics strategy that enables an effective, collaborative, responsible, well-regulated, and patient centred environment where genome research and clinical genomics can thrive. We present eight recommendations that could be the pillars of a national genomics health strategy.
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The endoplasmic reticulum (ER) is a membranous intracellular organelle and the first compartment of the secretory pathway. As such, the ER contributes to the production and folding of approximately one-third of cellular proteins, and is thus inextricably linked to the maintenance of cellular homeostasis and the fine balance between health and disease. Specific ER stress signalling pathways, collectively known as the unfolded protein response (UPR), are required for maintaining ER homeostasis. The UPR is triggered when ER protein folding capacity is overwhelmed by cellular demand and the UPR initially aims to restore ER homeostasis and normal cellular functions. However, if this fails, then the UPR triggers cell death. In this review, we provide a UPR signalling-centric view of ER functions, from the ER's discovery to the latest advancements in the understanding of ER and UPR biology. Our review provides a synthesis of intracellular ER signalling revolving around proteostasis and the UPR, its impact on other organelles and cellular behaviour, its multifaceted and dynamic response to stress and its role in physiology, before finally exploring the potential exploitation of this knowledge to tackle unresolved biological questions and address unmet biomedical needs. Thus, we provide an integrated and global view of existing literature on ER signalling pathways and their use for therapeutic purposes.
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Estresse do Retículo Endoplasmático , Retículo Endoplasmático/patologia , Resposta a Proteínas não Dobradas , Animais , Retículo Endoplasmático/metabolismo , Homeostase , Humanos , Transdução de SinaisRESUMO
BACKGROUND: Microarrays have been widely used for the analysis of gene expression and several commercial platforms are available. The combined use of multiple platforms can overcome the inherent biases of each approach, and may represent an alternative that is complementary to RT-PCR for identification of the more robust changes in gene expression profiles. In this paper, we combined statistical and functional analysis for the cross platform validation of two oligonucleotide-based technologies, Affymetrix (AFFX) and Applied Biosystems (ABI), and for the identification of differentially expressed genes. RESULTS: In this study, we analysed differentially expressed genes after treatment of an ovarian carcinoma cell line with a cell cycle inhibitor. Treated versus control RNA was analysed for expression of 16425 genes represented on both platforms. We assessed reproducibility between replicates for each platform using CAT plots, and we found it high for both, with better scores for AFFX. We then applied integrative correlation analysis to assess reproducibility of gene expression patterns across studies, bypassing the need for normalizing expression measurements across platforms. We identified 930 genes as differentially expressed on AFFX and 908 on ABI, with approximately 80% common to both platforms. Despite the different absolute values, the range of intensities of the differentially expressed genes detected by each platform was similar. ABI showed a slightly higher dynamic range in FC values, which might be associated with its detection system. 62/66 genes identified as differentially expressed by Microarray were confirmed by RT-PCR. CONCLUSION: In this study we present a cross-platform validation of two oligonucleotide-based technologies, AFFX and ABI. We found good reproducibility between replicates, and showed that both platforms can be used to select differentially expressed genes with substantial agreement. Pathway analysis of the affected functions identified themes well in agreement with those expected for a cell cycle inhibitor, suggesting that this procedure is appropriate to facilitate the identification of biologically relevant signatures associated with compound treatment. The high rate of confirmation found for both common and platform-specific genes suggests that the combination of platforms may overcome biases related to probe design and technical features, thereby accelerating the identification of trustworthy differentially expressed genes.
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Biomarcadores Tumorais/metabolismo , Perfilação da Expressão Gênica/métodos , Proteínas de Neoplasias/análise , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias Ovarianas/metabolismo , Linhagem Celular Tumoral , Interpretação Estatística de Dados , Feminino , Perfilação da Expressão Gênica/instrumentação , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Maternity care is facing increasing intervention and iatrogenic morbidity rates. This can be attributed, in part, to higher-risk maternity populations, but also to a risk culture in which birth is increasingly seen as abnormal. Technology and intervention are used to prevent perceived implication in adverse outcomes and litigation. QUESTION: Does midwives' and obstetricians' perception of risk affect care practices for normal birth and low-risk women in labour, taking into account different settings? METHODS: The research methods are developed within a qualitative framework. Data were collected using semi-structured interviews and analysed thematically. A purposive sample of 25 midwives and obstetricians were recruited from three maternity settings in Ireland. This included obstetric-led hospitals, an alongside midwifery-led unit and the community. FINDINGS: Midwifery is assuming a peripheral position with regard to normal birth as a progressive culture of risk and medicalisation affects the provision of maternity care. This is revealed in four themes; (1) professional autonomy and hierarchy in maternity care; (2) midwifery-led care as an undervalued and unsupported aspiration; (3) a shift in focus from striving for normality to risk management; and (4) viewing pregnancy through a 'risk-lens'. DISCUSSION: Factors connected to the increased medicalisation of birth contribute to the lack of midwifery responsibility for low-risk women and normal birth. Midwives are resigned to the current situation and as a profession are reluctant to take action. CONCLUSION: Improved models of care, distinct from medical jurisdiction, are required. Midwives must take responsibility for leading change as their professional identity is in jeopardy.
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Atitude do Pessoal de Saúde , Parto Obstétrico/métodos , Relações Enfermeiro-Paciente , Obstetrícia/normas , Relações Médico-Paciente , Feminino , Humanos , Irlanda , Tocologia , Parto , GravidezRESUMO
BACKGROUND: Risk and risk assessment are increasingly affecting how maternity services are governed with rates of intervention continuing to rise in obstetric-led services for low-risk women. AIM: This review synthesises original research that examines how perceptions of risk impact on midwives' and obstetricians' facilitation of care for low-risk women in labour. METHODS: A five stage process for conducting integrative reviews was employed. A robust search strategy incorporated electronic searches in The Cochrane Database of Systematic Reviews, EBSCO, EMBASE and Scopus from 2009 to 2014. The initial search resulted in the retrieval of 2429 articles which were reduced to 14 through a systematic process. FINDINGS: The results of this review revealed an over-arching theme of an assumption of abnormality in the birthing process leading to unnecessary intervention and surveillance. Three sub-themes are presented under this central theme - (1) external influences on risk perception that include practice guidelines and professional responsibility; (2) influence of personal fears and values on risk perception focusing on differing attitudes to physiological birth; (3) impact of professionals' perceptions of risk on women's decision-making in labour. CONCLUSION: Practice is influenced by an assumption of birth as abnormal and is compounded by issues such as institutional risk management, lack of midwifery responsibility, fear of involvement in adverse outcomes and personal values regarding physiological birth. These findings suggest that a shift in focus away from risk and towards health and wellbeing in the planning of maternity care may go some way towards providing a solution to the increasing intervention rates for low-risk women.
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Tomada de Decisões , Trabalho de Parto/psicologia , Tocologia/métodos , Enfermeiros Obstétricos/psicologia , Obstetrícia/métodos , Médicos/psicologia , Adulto , Feminino , Humanos , Parto , Percepção , Gravidez , Inquéritos e QuestionáriosRESUMO
DNA replication is an essential process for cell division and as such it is a process that is directly targeted by several anticancer drugs. CDC7 plays an essential role in the activation of replication origins and has recently been proposed as a novel target for drug discovery. The MCM DNA helicase complex (MCM2-7) is a key target of the CDC7 kinase, and MCM phosphorylation status at specific sites is a reliable biomarker of CDC7 cellular activity. In this work we describe a cell-based assay that utilizes the "In Cell Western Technique" (ICW) to identify compounds that affect cellular CDC7 activity. By screening a library of approved drugs and kinase inhibitors we found several compounds that can affect CDC7-dependent phosphorylation of MCM2 in HeLa cells. Among these, Mitoxantrone, a topoisomerase inhibitor, and Ryuvidine, previously described as a CDK4 inhibitor, cause a reduction in phosphorylated MCM2 levels and a sudden blockade of DNA synthesis that is accompanied by an ATM-dependent checkpoint response. This study sheds light on the previously observed cytotoxity of Ryuvidine, strongly suggesting that it is related to its effect of causing DNA damage.
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Dano ao DNA/efeitos dos fármacos , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Ensaios de Triagem em Larga Escala/métodos , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Replicação do DNA/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/química , Células HeLa , Humanos , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Reprodutibilidade dos Testes , Bibliotecas de Moléculas PequenasRESUMO
Death receptors are members of the tumour necrosis factor (TNF) receptor superfamily characterised by an ~80 amino acid long alpha-helical fold, termed the death domain (DD). Death receptors diversified during early vertebrate evolution indicating that the DD fold has plasticity and specificity that can be easily adjusted to attain additional functions. Eight members of the death receptor family have been identified in humans, which can be divided into four structurally homologous groups or clades, namely: the p75(NTR) clade (consisting of ectodysplasin A receptor, death receptor 6 (DR6) and p75 neurotrophin (NTR) receptor); the tumour necrosis factor receptor 1 clade (TNFR1 and DR3), the CD95 clade (CD95/FAS) and the TNF-related apoptosis-inducing ligand receptor (TRAILR) clade (TRAILR1 and TRAILR2). Receptors in the same clade participate in similar processes indicating that structural diversification enabled functional specialisation. On the surface of nearly all human cells multiple death receptors are expressed, enabling the cell to respond to a plethora of external signals. Activation of different death receptors converges on the activation of three main signal transduction pathways: nuclear factor-κB-mediated differentiation or inflammation, mitogen-associated protein kinase-mediated stress response and caspase-mediated apoptosis. While the ability to induce cell death is true for nearly all DRs, the FAS and TRAILR clades have specialised in inducing cell death. Here we summarise recent discoveries about the molecular regulation and structural requirements of apoptosis induction by death receptors and discuss how this information can be used to better explain the biological functions, similarities and distinguishing features of death receptors.
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Apoptose/fisiologia , Proteínas Adaptadoras de Sinalização de Receptores de Domínio de Morte/metabolismo , Receptores de Morte Celular/metabolismo , Animais , Humanos , Processamento de Proteína Pós-Traducional , Transdução de SinaisRESUMO
Two key features of myeloma cells are the deregulation of the cell cycle and the dependency on the expression of the BCL2 family of anti-apoptotic proteins. The cell division cycle 7 (CDC7) is an essential S-phase kinase and emerging CDC7 inhibitors are effective in a variety of preclinical cancer models. These compounds also inhibit CDK9 which is relevant for MCL-1 expression. The activity and mechanism of action of the dual CDC7/CDK9 inhibitor PHA-767491 was assessed in a panel of multiple myeloma cell lines, in primary samples from patients, in the presence of stromal cells and in combination with drugs used in current chemotherapeutic regimens. We report that in all conditions myeloma cells undergo cell death upon PHA-767491 treatment and we report an overall additive effect with melphalan, bortezomib and doxorubicin, thus supporting further assessment of targeting CDC7 and CDK9 in multiple myeloma.
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The endoplasmic reticulum (ER) is an elaborate cellular organelle essential for cell function and survival. Conditions that interfere with ER function lead to the accumulation and aggregation of unfolded proteins which are detected by ER transmembrane receptors that initiate the unfolded protein response (UPR) to restore normal ER function. If the ER stress is prolonged, or the adaptive response fails, apoptotic cell death ensues. Many studies have focused on how this failure initiates apoptosis, particularly because ER stress-induced apoptosis is implicated in the pathophysiology of several neurodegenerative and cardiovascular diseases. In this review we aim to shed light on the proteins that are not core components of the UPR signaling pathway but which can influence the course of the ER stress response by regulating the switch from the adaptive phase to apoptosis.
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Apoptose/fisiologia , Estresse do Retículo Endoplasmático/fisiologia , Animais , Humanos , Modelos Biológicos , Transdução de Sinais/fisiologia , Resposta a Proteínas não Dobradas/fisiologiaRESUMO
Aurora kinases represent an appealing target for anticancer therapies and several Aurora inhibitors are in clinical development, including the potent pan-Aurora inhibitor Danusertib. Treatment with Aurora inhibitors has been shown to induce diverse biological responses in different tumor cells, in part depending on TP53 status. To characterize the effects of Danusertib at the transcriptional level we carried out gene expression profiling of wt and TP53 mutant tumor cells showing differential cell cycle response upon drug treatment. We found that treatment with Danusertib induces a strong transcriptional response only in TP53 wt cells, with an overlapping pattern of expression of TP53-dependent genes among the three cell lines tested, while a prevalent signature could not be identified in the two TP53 mutant cells, suggesting that TP53 status is a key determinant for the observed transcriptional effects. This work led to the identification of a number of genes consistently modulated by Aurora treatment in TP53 cells. One of these is GDF15, a secreted protein belonging to the TGF-ß superfamily, for which we found a potential role in resistance to Danusertib, and which could represent a potential biomarker for Danusertib treatment in TP53 WT tumors and in surrogate tissues such as blood or skin.
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Benzamidas/farmacologia , Genes p53/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Aurora Quinases , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Marcadores Genéticos , Humanos , Transcrição Gênica/efeitos dos fármacosRESUMO
Microarray experiments are affected by several sources of variability. The paper demonstrates the major role of the day-to-day variability, it underlines the importance of a randomized block design when processing replicates over several days to avoid systematic biases and it proposes a simple algorithm that minimizes the day dependence.
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Algoritmos , Biologia Computacional/normas , Perfilação da Expressão Gênica/normas , Análise de Sequência com Séries de Oligonucleotídeos/normas , Linhagem Celular Tumoral , Análise por Conglomerados , Humanos , Modelos Estatísticos , Sondas Moleculares , Reprodutibilidade dos TestesRESUMO
During apoptosis, the process of mitochondrial outer membrane permeabilization (MOMP) represents a point-of-no-return as it commits the cell to death. Here we have assessed the role of caspases, Bcl-2 family members and the mitochondrial permeability transition pore on ER stress-induced MOMP and subsequent cell death. Induction of ER stress leads to upregulation of several genes such as Grp78, Edem1, Erp72, Atf4, Wars, Herp, p58ipk, and ERdj4 and leads to caspase activation, release of mitochondrial intermembrane proteins and dissipation of mitochondrial transmembrane potential (DeltaPsim). Mouse embryonic fibroblasts (MEFs) from caspase-9, -2 and, -3 knock-out mice were resistant to ER stress-induced apoptosis which correlated with decreased processing of pro-caspase-3 and -9. Furthermore, pretreatment of cells with caspase inhibitors (Boc-D.fmk and DEVD.fmk) attenuated ER stress-induced loss of DeltaPsim. However, only deficiency of caspase-9 and -2 could prevent ER stress-mediated loss of DeltaPsim. Bcl-2 overexpression or pretreatment of cells with the cell permeable BH4 domain (BH4-Tat) or the mitochondrial permeability transition pore inhibitors, bongkrekic acid or cyclosporine A, attenuated the ER stress-induced loss of DeltaPsim. These data suggest a role for caspase-9 and -2, Bcl-2 family members and the mitochondrial permeability transition pore in loss of mitochondrial membrane potential during ER stress-induced apoptosis.
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The endoplasmic reticulum (ER) is the site of synthesis and folding of secretory and membrane bound proteins. The capacity of the ER to process proteins is limited and the accumulation of unfolded and misfolded proteins can lead to ER stress which has been associated with a wide range of diseases including cancer. In this review we initially provide an overview of our current understanding of how cells respond to ER stress at the molecular level and the key players involved in mediating the unfolded protein response (UPR). We review the evidence suggesting that the ER stress response could be important for the growth and development of tumors under stressful growth conditions such as hypoxia or glucose deprivation, which are commonly encountered by most solid tumors, and we analyse how it may be possible to exploit the unfolded protein response as an anticancer strategy. Two approaches to target the unfolded protein response are proposed-the first involves inhibiting components of the unfolded protein response so cells cannot adapt to stressful conditions and the second involves overloading the unfolded protein response so the cell is unable to cope, leading to cell death. We focused on proteins with an enzymatic activity that can be targeted by small molecule inhibitors as this is one of the most common approaches utilized by drug discovery companies. Finally, we review drugs currently in clinical development that affect the ER stress response and that may have potential as anti-tumor agents alone or in combination with other chemotherapeutics.