RESUMEN
Cardiovascular diseases are major causes of mortality and morbidity. Cardiomyocyte apoptosis disrupts cardiac function and leads to cardiac decompensation and terminal heart failure. Delineating the regulatory signaling pathways that orchestrate cell survival in the heart has significant therapeutic implications. Cardiac tissue has limited capacity to regenerate and repair. Stem cell therapy is a successful approach for repairing and regenerating ischemic cardiac tissue; however, transplanted cells display very high death percentage, a problem that affects success of tissue regeneration. Stem cells display multipotency or pluripotency and undergo self-renewal, however these events are negatively influenced by upregulation of cell death machinery that induces the significant decrease in survival and differentiation signals upon cardiovascular injury. While efforts to identify cell types and molecular pathways that promote cardiac tissue regeneration have been productive, studies that focus on blocking the extensive cell death after transplantation are limited. The control of cell death includes multiple networks rather than one crucial pathway, which underlies the challenge of identifying the interaction between various cellular and biochemical components. This review is aimed at exploiting the molecular mechanisms by which stem cells resist death signals to develop into mature and healthy cardiac cells. Specifically, we focus on a number of factors that control death and survival of stem cells upon transplantation and ultimately affect cardiac regeneration. We also discuss potential survival enhancing strategies and how they could be meaningful in the design of targeted therapies that improve cardiac function.
Asunto(s)
Apoptosis , Corazón/fisiología , Células Madre Multipotentes/fisiología , Infarto del Miocardio/cirugía , Células Madre Pluripotentes/fisiología , Regeneración/fisiología , Animales , Bioingeniería/métodos , Supervivencia Celular , Exosomas/metabolismo , Terapia Genética , Humanos , Precondicionamiento Isquémico Miocárdico , MicroARNs/fisiología , Células Madre Multipotentes/trasplante , Infarto del Miocardio/patología , Miocitos Cardíacos/patología , Células Madre Pluripotentes/trasplante , Especies Reactivas de Oxígeno/metabolismo , Transducción de SeñalRESUMEN
Aziridinylquinone RH-1 (2,5-diaziridinyl-3-hydroxymethyl-6-methyl-cyclohexa-2,5-diene-1,4-dione) is a potential anticancer agent. RH-1 action is associated with NAD(P)H: quinone oxidoreductase (NQO1) which reduces this diaziridinylbenzoquinone into DNA-alkylating hydroquinone and is overexpressed in many tumors. Another suggested mechanism of RH-1 toxicity is the formation of reactive oxygen species (ROS) arising from its redox cycling. In order to improve anticancer action of this and similar antitumor quinones, we investigated the involvement of different signaling molecules in cytotoxicity induced by RH-1 by using wild-type tumor suppressor p53 bearing nonsmall cell lung carcinoma A549 cells as a model. Gradual and prolonged increase of mitogen-activated protein kinases (MAPK) ERK, P38, and JNK phosphorylation was observed during 24-h RH-1 treatment. In parallel, activation of DNA damage-sensing ATM kinase, upregulation, and phosphorylation of TP53 (human p53) took place. Inhibition studies revealed that RH-1-induced A549 apoptosis involved the NQO1-ATM-p53 signaling pathway and ROS generation. TP53 participated in ROS- and DNA damage-induced cell death differently. Moreover, MAP kinase JNK was another TP53 activator and death inducer in A549 cells. At the same time, rapid and prolonged activation of AKT kinase during RH-1 treatment was found, and it proved to be antiapoptotic kinase in our model system. Therefore, we identified that different and opposite cell death regulating signaling pathways, which may counteract one another, are induced in cancer cells during chemotherapeutic RH-1 treatment.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Aziridinas/farmacología , Ciclohexenos/farmacología , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Aziridinas/química , Aziridinas/metabolismo , Línea Celular Tumoral , Ciclohexenos/química , Ciclohexenos/metabolismo , Daño del ADN , Humanos , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Toxicity and the emergence of resistance are the main challenges in cancer treatment. The optimal dose of cisplatin, one of the most widely used chemotherapeutic anticancer drugs, is currently being widely debated. Furthermore, the dose-dependent molecular mechanisms of its action are poorly understood. To assess the role of protein kinase JNK (cJun N-terminal kinase) signaling in lung cancer treatment, we combined small-molecule JNK inhibitors and cisplatin. Wild-type p53 (tumor suppressor transcription factor TP53) and mutated RAS-bearing lung adenocarcinoma cell line A549 was used as a model in our studies. Here, we demonstrate cisplatin concentration-dependent opposing roles of JNK in killing cancer cells: a cell-protective role at low cisplatin concentrations and an apoptosis-promoting (or neutral) role at high concentrations. Time- and dose-dependent activation of pro-survival protein kinase AKT and TP53 was shown, with similar activation dynamics in cells exposed to different (low and high) cisplatin concentrations. Selective inhibition of AKT and activation of TP53 (expression and phosphorylation) led to a decrease in cell survival, indicating their involvement in cisplatin-induced cell death regulation. The activation levels of TP53 and AKT in cisplatin-treated A549 cells after cotreatment with the JNK inhibitor SP600125 correlated with their role in regulating cell death. TP53 and AKT were proposed as signaling proteins mediating the outcome of JNK inhibition in A549 cells exposed to different concentrations of cisplatin. Our findings suggest that a combination of stress kinase JNK inhibition and low-dose cisplatin, together with manipulation of drug-induced signaling, could be considered as a promising treatment strategy for certain lung cancers.
RESUMEN
Improvement in the yield of adult organism stem cells, and the ability to manage their differentiation and survival potential are the major goals in their application in regenerative medicine and in the adult stem cell research. We have demonstrated that adult rabbit muscle-derived cell lines with an unlimited proliferative potential in vitro can differentiate into myogenic, osteogenic, adipogenic and neurogenic lineages. Studies of cell survival in vitro showed that differentiated cells, except neurogenic ones, are more resistant to apoptosis inducers compared to proliferating cells. Resistance to death signals correlated with the level of protein kinase AKT phosphorylation. Skeletal muscle-derived cell lines can be multipurpose tools in therapy. Enhanced resistance of differentiated cells to certain types of damage shows their potential for long-term survival and maintenance in an organism. This article was published online on 29 January 2013. An error was subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 6 March 2013.
Asunto(s)
Apoptosis/efectos de los fármacos , Diferenciación Celular , Animales , Técnicas de Cultivo de Célula , Línea Celular , Supervivencia Celular , Cromonas/farmacología , Morfolinas/farmacología , Músculo Esquelético/citología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ConejosRESUMEN
Daunorubicin (as well as other anthracyclines) is known to be toxic to heart cells and other cells in organism thus limiting its applicability in human cancer therapy. To investigate possible mechanisms of daunorubicin cytotoxicity, we used stem cell lines derived from adult rabbit skeletal muscle. Recently, we have shown that daunorubicin induces apoptotic cell death in our cell model system and distinctly influences the activity of MAP kinases. Here, we demonstrate that two widely accepted antagonistic signalling pathways namely proapoptotic JNK and prosurvival PI3K/AKT participate in apoptosis. Using the Western blot method, we observed the activation of JNK and phosphorylation of its direct target c-Jun along with inactivation of AKT and its direct target GSK in the course of programmed cell death. By means of small-molecule kinase inhibitors and transfection of cells with the genes of the components of these pathways, c-Jun and AKT, we confirm that JNK signalling pathway is proapoptotic, whereas AKT is antiapoptotic in daunorubicin-induced muscle cells. These findings could contribute to new approaches which will result in less toxicity and fewer side effects that are currently associated with the use of daunorubicin in cancer therapies.
Asunto(s)
Antibióticos Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Daunorrubicina/toxicidad , Músculo Esquelético/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Células Madre/efectos de los fármacos , Animales , Western Blotting , Técnicas de Cultivo de Célula , Línea Celular , Supervivencia Celular/efectos de los fármacos , Glucógeno Sintasa Quinasas/antagonistas & inhibidores , Glucógeno Sintasa Quinasas/metabolismo , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Músculo Esquelético/enzimología , Músculo Esquelético/patología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , Conejos , Células Madre/enzimología , Células Madre/patologíaRESUMEN
There is no doubt that cell signaling manipulation is a key strategy for anticancer therapy. Furthermore, cell state determines drug response. Thus, establishing the relationship between cell state and therapeutic sensitivity is essential for the development of cancer therapies. In the era of personalized medicine, the use of patient-derived ex vivo cell models is a promising approach in the translation of key research findings into clinics. Here, we were focused on the non-oncogene dependencies of cell resistance to anticancer treatments. Signaling-related mechanisms of response to inhibitors of MEK/ERK and PI3K/AKT pathways (regulators of key cellular functions) were investigated using a panel of patients' lung tumor-derived cell lines with various stemness- and EMT-related markers, varying degrees of ERK1/2 and AKT phosphorylation, and response to anticancer treatment. The study of interactions between kinases was the goal of our research. Although MEK/ERK and PI3K/AKT interactions are thought to be cell line-specific, where oncogenic mutations have a decisive role, we demonstrated negative feedback loops between MEK/ERK and PI3K/AKT signaling pathways in all cell lines studied, regardless of genotype and phenotype differences. Our work showed that various and distinct inhibitors of ERK signaling - selumetinib, trametinib, and SCH772984 - increased AKT phosphorylation, and conversely, inhibitors of AKT - capivasertib, idelalisib, and AKT inhibitor VIII - increased ERK phosphorylation in both control and cisplatin-treated cells. Interaction between kinases, however, was dependent on cellular state. The feedback between ERK and AKT was attenuated by the focal adhesion kinase inhibitor PF573228, and in cells grown in suspension, showing the possible role of extracellular contacts in the regulation of crosstalk between kinases. Moreover, studies have shown that the interplay between MEK/ERK and PI3K/AKT signaling pathways may be dependent on the strength of the chemotherapeutic stimulus. The study highlights the importance of spatial location of the cells and the strength of the treatment during anticancer therapy.
RESUMEN
The use of cultured cells as a tool for research, precision medicine, biopharmacy, and biomanufacturing is constantly increasing. In parallel, the role of cell-cell and cell-substratum contacts in cell functioning is increasingly validated. Adhesion signalling plays a key role here. The activity of cell fate-regulating signalling molecules is an important factor in determining cell behaviour, as well as their response to treatment, depending on cell phenotypic status and location in the body. Three cellular state models (adherent, single cells in suspension, and aggregated cells) were compared for cell signalling, including focal adhesion (FAK), mitogen-activated (MAPK), as well as Akt protein kinases, and transcription factor cJun, by using lung adenocarcinoma A549, muscle-derived stem Myo, as well as primary lung cancer cell lines. Survival of both A549 and Myo cells was dependent on kinases Akt and ERK in detached conditions. Intercellular contacts in aggregates promoted activation of Akt and ERK, and cell survival. Loss of contacts with the substrate increased phosphorylation of MAP kinases JNK and p38, while decreased Akt phosphorylation by processes involving FAK. Unexpectedly, detachment increased phosphorylation of antiapoptotic kinase ERK in A549, while in Myo stem cells ERK phosphorylation was downregulated. JNK target transcription factor cJun protein level was markedly diminished by contacts between cells possibly involving mechanism of proteasomal degradation. Furthermore, studies revealed the opposite dependence of molecules of the same signalling pathway - phospho-cJun and phospho-JNK - on cell culture density. Differences in ERK activation under detachment conditions indicate that targeting of prosurvival kinases during anoikis should be different in different cells. Moreover, the outcome of JNK activation in cells may depend on the amount of cJun, which is determined by cell-cell contacts.
Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Anoicis , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
A wide variety of agents have been traditionally used in cardiovascular medicine worldwide and their precise mechanisms of action have been demonstrated to be largely related to the cardiomyocyte mitochondria and apoptosis. Abnormalities in the structure and function of the mitochondria and mutations in mitochondrial DNA can decrease energy production, alter the redox system, impair calcium homeostasis, and induce the mitochondrial permeability transition pore (MPTP), causing cell death. All of these data provide evidence of mitochondrial signaling pathways as targets to downregulate cardiac cell apoptosis and thus to prevent and treat cardiovascular diseases. This review focuses on the protective roles of various agents, mostly natural compounds, which express beneficial effects on mitochondrial function and suspend the apoptotic signaling mechanisms by modulating the activity of mitogen-activated protein kinases (MAPKs). Examining cellular and molecular targets of these agents offers essential experimental information for future pharmacological studies, drug discovery, clinical trials and applications.
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Apoptosis/efectos de los fármacos , Productos Biológicos/farmacología , Cardiotónicos/farmacología , Corazón/efectos de los fármacos , Mitocondrias Cardíacas/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Animales , Humanos , Mitocondrias Cardíacas/metabolismo , Miocitos Cardíacos/metabolismoRESUMEN
Recent evidence shows that tumor microenvironment containing heterogeneous cells may be involved in cancer initiation, growth and tumor cell response to anticancer therapy. Chemotherapy was designed to make toxic impact on malicious cells in organisms, however, the means to protect healthy cells against chemical toxicity are still unsuccessful. As known, the majority of tumor surrounding cells are cancer-associated adipocytes which influence cancer development, progression and treatment. Targeting the components of tumor microenvironment in combination with conventional cancer treatment may become an effective cancer therapy strategy. However, little is known about adipocyte death mechanisms during combined chemo- and targeted therapy. The importance of c-Jun-NH