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Targeting autophagy might be a promising anticancer strategy; however, the dual roles of autophagy in cancer development and malignancy remain unclear. NSCLC (non-small cell lung cancer) cells harbour high levels of SQSTM1 (sequestosome 1), the autophagy receptor that is critical for the dual roles of autophagy. Therefore, mechanistic insights into SQSTM1 modulation may point towards better approaches to treat NSCLC. Herein, we used multiple autophagy flux models and autophagy readouts to show that aldo-keto reductase family 1 member C1 (AKR1C1), which is highly expressed in NSCLC, promotes autophagy by directly binding to SQSTM1 in a catalytic-independent manner. This interaction may be strengthened by reactive oxygen species (ROS), important autophagy inducers. Further mechanistic research demonstrated that AKR1C1 interacts with SQSTM1 to augment SQSTM1 oligomerization, contributing to the SQSTM1 affinity for binding cargo. Collectively, our data reveal a catalytic-independent role of AKR1C1 for interacting with SQSTM1 and promoting autophagy. All these findings not only reveal a novel functional role of AKR1C1 in the autophagy process but also indicate that modulation of the AKR1C1-SQSTM1 interaction may be a new strategy for targeting autophagy.
Assuntos
Aldo-Ceto Redutases/metabolismo , Autofagia/fisiologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Estresse Oxidativo/fisiologia , Proteína Sequestossoma-1/metabolismo , Linhagem Celular Tumoral , HumanosRESUMO
The current COVID-19 pandemic, caused by SARS-CoV-2, has impacted many facets of hematopoietic cell transplantation (HCT) in both developed and developing countries. Realizing the challenges as a result of this pandemic affecting the daily practice of the HCT centers and the recognition of the variability in practice worldwide, the Worldwide Network for Blood and Marrow Transplantation (WBMT) and the Center for International Blood and Marrow Transplant Research's (CIBMTR) Health Services and International Studies Committee have jointly produced an expert opinion statement as a general guide to deal with certain aspects of HCT, including diagnostics for SARS-CoV-2 in HCT recipient, pre- and post-HCT management, donor issues, medical tourism, and facilities management. During these crucial times, which may last for months or years, the HCT community must reorganize to proceed with transplantation activity in those patients who urgently require it, albeit with extreme caution. This shared knowledge may be of value to the HCT community in the absence of high-quality evidence-based medicine. © 2020 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.
Assuntos
Transplante de Medula Óssea , COVID-19/diagnóstico , COVID-19/terapia , Transplante de Células-Tronco Hematopoéticas , SARS-CoV-2 , COVID-19/epidemiologia , HumanosRESUMO
Use of the conventional cancer chemotherapy (i.e. vincristine) is limited in tumor cells exhibiting pre-existing or acquired resistance. Here, we found that C6 ceramide (C6) dramatically sensitized vincristine's activity. In vitro, C6 and vincristine coadministration induced substantial necrosis and apoptosis in multiple human cancer cell lines, which were accompanied by a profound AMP-activated protein kinase (AMPK) activation, subsequent p53 activation, mTORC1 inactivation and Bcl-2/HIF-1α downregulation. Such synergistic effects were attenuated by AMPK inactivation through genetic mutation or short hairpin RNA silencing. Coadministration-activated p53 translocated to mitochondria, and formed a complex with cyclophilin-D, leading to mitochondrial permeability transition pore opening and cell necrosis. Disrupting p53-Cyp-D complexation through pharmacological or genetic means reduced costimulation-induced cytotoxicity. In vivo, a liposomal C6 was synthesized, which dramatically enhanced the antiproliferative activity of vincristine on HCT-116 or A2780 xenografts. Together, C6 sensitizes vincristine-induced anticancer activity in vivo and in vitro, involving activating AMPK-p53 signaling.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ceramidas/farmacologia , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Vincristina/farmacologia , Proteínas Quinases Ativadas por AMP/genética , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Ciclofilinas/metabolismo , Regulação para Baixo , Sinergismo Farmacológico , Células HCT116 , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Potencial da Membrana Mitocondrial , Camundongos , Camundongos SCID , Mitocôndrias/fisiologia , Complexos Multiproteicos/metabolismo , Necrose/induzido quimicamente , Transplante de Neoplasias , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Interferência de RNA , RNA Interferente Pequeno , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Transplante Heterólogo , Proteína Supressora de Tumor p53/genéticaRESUMO
MicroRNAs (miRs) dysregulation is a general feature of colorectal cancer (CRC) and other solid tumors, and is associated cancer progression. In the current study, we demonstrate that microRNA-101 (miR-101) inhibits CRC cells probably through down-regulating sphingosine kinase 1 (SphK1). Our results showed that exogenously expressing miR-101 inhibited CRC cell (HT-29 and HCT-116 lines) growth in vitro. At the molecular level, miR-101 dramatically down-regulated SphK1 mRNA and protein expression, causing pro-apoptotic ceramide production in above CRC cells. On the other hand, inhibition of miR-101 through expressing antagomiR-101 increased SphK1 expression to down-regulate ceramide level in HT-29 cells. miR-101 expression increased the in vitro anti-CRC activity of conventional chemo-agents: paclitaxel and doxorubicin. CRC cells with SphK1-shRNA knockdown showed similar phenotypes as the miR-101-expressed CRC cells, presenting with elevated level of ceramide and high sensitivity to paclitaxel or doxorubicin. In vivo, HCT-116 xenograft growth in severe combined immuno-deficient (SCID) mice was dramatically inhibited by over-expressing miR-101. Further, miR-101 enhanced paclitaxel-induced anti-HCT-116 activity in vivo. Together, these results indicate that miR-101 exerts its anti-CRC activities probably through down-regulating SphK1.
Assuntos
Neoplasias Colorretais/enzimologia , Regulação para Baixo/fisiologia , MicroRNAs/fisiologia , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Sequência de Bases , Divisão Celular/fisiologia , Neoplasias Colorretais/patologia , Primers do DNA , Células HT29 , Humanos , Camundongos , Camundongos SCID , Paclitaxel/farmacologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
In this study, we tested the potential role of astragaloside IV (AS-IV) against oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damages in murine cortical neurons, and studied the associated signaling mechanisms. AS-IV exerted significant neuroprotective effects against OGD/R by reducing reactive oxygen species (ROS) accumulation, thereby attenuating oxidative stress and neuronal cell death. We found that AS-IV treatment in cortical neurons resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by Nrf2 Ser-40 phosphorylation, and its nuclear localization, as well as transcription of antioxidant-responsive element (ARE)-regulated genes: heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and sulphiredoxin 1 (SRXN-1). Knockdown of Nrf2 through lentiviral shRNAs prevented AS-IV-induced ARE genes transcription, and abolished its anti-oxidant and neuroprotective activities. Further, we discovered that AS-IV stimulated heparin-binding-epidermal growth factor (HB-EGF) release to trans-activate epidermal growth factor receptor (EGFR) in cortical neurons. Blockage or silencing EGFR prevented Nrf2 activation by AS-IV, thus inhibiting AS-IV-mediated anti-oxidant and neuroprotective activities against OGD/R. In summary, AS-IV protects cortical neurons against OGD/R damages through activating of EGFR-Nrf2 signaling.
Assuntos
Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Receptores ErbB/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Traumatismo por Reperfusão/metabolismo , Saponinas/farmacologia , Triterpenos/farmacologia , Animais , Antioxidantes/farmacologia , Córtex Cerebral/lesões , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Técnicas de Silenciamento de Genes , Camundongos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Cultura Primária de Células , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/prevenção & controle , Ativação Transcricional/efeitos dos fármacosRESUMO
Colorectal cancer (CRC) causes significant mortalities worldwide. Fibroblast growth factor (FGF) receptor (FGFR) signaling is frequently dysregulated and/or constitutively activated in CRCs, contributing to cancer carcinogenesis and progression. Here, we studied the activity of AZD-4547, a novel and potent FGFR kinase inhibitor, on CRC cells. AZD-4547 inhibited CRC cell growth in vitro, and its activity correlated with the FGFR-1/2 expression level. AZD-4547 was cytotoxic and pro-apoptotic in FGFR-1/2-expressed CRC cell lines (NCI-H716 and HCT-116), but not in FGFR-1/2 null HT-29 cells. Further, AZD-4547 inhibited cell cycle progression and attenuated the activation of FGFR1-FGFR substrate 2 (FRS-2), ERK/mitogen-activated protein kinase (MAPK), and AKT/mammalian target of rapamycin (AKT/mTOR) signalings in NCI-H716 and HCT-116 cells. In vivo, AZD-4547 oral administration at effective doses inhibited NCI-H716 (high FGFR-1/2 expression) xenograft growth in nude mice. Phosphorylation of FGFR-1, AKT, and ERK1/2 in xenograft specimens was also inhibited by AZD-4547 administration. Thus, our preclinical studies strongly support possible clinical investigations of AZD-4547 for the treatment of CRCs harboring deregulated FGFR signalings.
Assuntos
Benzamidas/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Piperazinas/administração & dosagem , Pirazóis/administração & dosagem , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/biossíntese , Animais , Carcinogênese/efeitos dos fármacos , Neoplasias Colorretais/patologia , Fatores de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Over past two years, a total of 39,918 hematopoietic stem cell transplantation (HSCT) cases were reported, with 18,194 and 21,714 transplants performed in 2022 and 2023, respectively. Autologous HSCT accounted for 6562 cases (31%) in 2022, while allogeneic HSCT comprised 12,632 cases (69%). In 2023, the number of allogeneic HSCTs exceeded 15,000, maintaining a 69% share. Participation in the 2022 and 2023 surveys included 193 and 212 transplantation teams, respectively, from 27 provinces, municipalities, or autonomous regions. The leading indication of HSCT was acute leukemia, including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and mixed phenotype acute leukemia, with a total of 17,421 cases. AML was the most common disease (10,339, 38%) for allogeneic HSCT, which was followed by ALL (5925 cases, 21%). Peripheral blood emerged as the primary source of stem cell grafts, utilized in 54% of matched sibling donor transplants and 77% of haploidentical donor transplants. The BuCy-based conditioning regimen was the most prevalent, used in 53% of allogeneic HSCT cases in the past two years. This survey offers a comprehensive overview of the current HSCT landscape and serves as a valuable resource for clinical practice.
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Oxidative stress-induced neuronal cell death requires opening of the mitochondrial permeability transition pore. P53 mitochondrial translocation and association with Cyclophilin D (Cyp-D) is required for the pore opening. Here we tested this signaling axis in oxygen glucose deprivation (OGD)/re-oxygenation-induced in vitro neuronal death. Using mitochondrion immunoprecipitation, we found that p53 translocated to mitochondrion and associated with Cyp-D in SH-SY5Y cells exposed to (OGD)/re-oxygenation. Disruption of this complex by Cyp-D inhibitor Cyclosporine A (CsA), or by Cyp-D or p53 deficiency, significantly inhibited OGD/re-oxygenation-induced apoptosis-independent cell death. Conversely, over-expression of Cyp-D in SH-SY5Y cells caused spontaneous cell death, and these cells were more vulnerable to OGD/re-oxygenation. Finally, CsA or Cyp-D RNAi suppressed OGD/re-oxygenation-induced neuronal cell death in primary cultures. Together, our study suggests that OGD/re-oxygenation-induced in vitro cell death involves a mitochondrial Cyp-D/p53 signaling axis.
Assuntos
Morte Celular/efeitos dos fármacos , Ciclofilinas/fisiologia , Proteínas de Transporte da Membrana Mitocondrial/fisiologia , Neurônios/patologia , Oxigênio/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Animais , Linhagem Celular Tumoral , Células Cultivadas , Peptidil-Prolil Isomerase F , Ciclosporina/farmacologia , Humanos , Camundongos , Poro de Transição de Permeabilidade Mitocondrial , Estresse Oxidativo/fisiologia , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/deficiênciaRESUMO
Opioid analgesics are the most common therapeutic analgesic for acute pain. In this study, the toxicological and pharmacological features of a group of opioid analgesics were characterized by the motility of human sperm. Aliquots of sperm were incubated with various concentrations of opioid analgesics in vitro. Computer-assisted sperm analysis was used to assess sperm motility at 15 minutes, 2 hours, and 4 hours after drug addition to the medium. Butorphanol and dezocine showed marked reduction of motility after incubation with sperm for 15 minutes. Butorphanol was more effective than dezocine in immobilizing sperm. Other opioids studied, such as fentanyl, alfentanil, and sufentanil, showed only partial inhibitory activity. Based on the data reported herein, we have found that butorphanol and dezocine exert a sperm-immobilizing effect. However, fentanyl, alfentanil, and sufentanil exhibit only partial inhibition of sperm motility. Given the increasing use of opioids and their potential effect on sperm motility, these findings are greatly relevant to male reproductive health.
Assuntos
Analgésicos Opioides/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Adulto , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/toxicidade , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Masculino , Fatores de TempoRESUMO
Our study shows that coadministration of curcumin and an orally bioactive alkylphospholipid perifosine results in a significant increase in colorectal cancer cell apoptosis and a marked inhibition of cell growth both in vitro and in vivo. This novel combinatorial regimen leads to changes of multiple cell signaling pathways including inactivation of Akt and nuclear factor-κB as well as activation of c-Jun N-terminal kinases and endoplasmic reticulum stress. Further, perifosine and curcumin synergistically increase intracellular level of reactive oxygen species and ceramide, and downregulate the expression of cyclin D1 and Bcl-2 in colorectal cancer cells. These changes at molecular level together account for the cancer cell apoptosis and growth inhibition. We conclude that perifosine sensitizes colorectal cancer cells to curcumin by modulating multiple signaling pathways. Adding perifosine with curcumin may represent an effective therapy regimen against colorectal cancers, and possible other aggressive tumors.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Curcumina/farmacologia , Fosforilcolina/análogos & derivados , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células CACO-2 , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ceramidas/metabolismo , Neoplasias Colorretais/patologia , Curcumina/administração & dosagem , Ciclina D1/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Retículo Endoplasmático/efeitos dos fármacos , Feminino , Células HCT116 , Células HT29 , Humanos , Proteínas I-kappa B/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos SCID , Complexos Multiproteicos , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilcolina/administração & dosagem , Fosforilcolina/farmacologia , Proteínas/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Many epidemiological studies have found that leptin correlates to body fat extent and breast cancer. Leptin exerts its physiological action through the leptin receptor (LEPR). However, published data on the association between LEPR alleles and breast cancer occurrence have led to in contradictory results. A total of 10 studies were identified to the meta-analysis, including 4,644 cases and 5,485 controls for LEPR rs1137101 polymorphism, 5 studies with 2,759 cases and 4,464 controls for rs1137100 polymorphism, and 2 studies for rs8051542, rs8051542, and rs8051542 polymorphisms. The pooled odds ratios (OR) with 95 % confidence intervals (CI) for breast cancer risk associated with LEPR genotypes were estimated. Elevated breast cancer risk was associated with LEPR rs1137101 polymorphism when all studies were pooled in the meta-analysis (allele contrast model: OR = 0.71, 95 % CI = 0.551-0.997). In the stratified analysis by ethnicity, significantly increased risks were also found among Asians for allele contrast model (OR 0.414, 95 % CI 0.312-0.550) and dominant model (OR 0.537, 95 % CI 0.370-0.781); for Africans, significantly increased risks were also found for allele contrast model (OR 0.716, 95 % CI 0.595-0.861), homozygote codominant (OR 0.537, 95 % CI 0.370-0.781) and dominant model (OR 1.595, 95 % CI 1.207-2.108). And significantly elevated breast cancer risk was associated with LEPR rs1137100 polymorphism for allele contrast (OR = 0.666, 95 % CI = 0.603-0.720) and homozygote codominant models (OR = 0.344, 95 % CI = 0.282-0.421). For LEPR rs8179183, rs4655537, and rs3762274 polymorphisms, no significant associations were detected in all comparison models. This pooled analysis suggested that rs1137101 and rs1137100 polymorphisms were significantly correlated with breast cancer risk and the A allele of LEPR rs1137101 variant and the G allele of LEPR rs1137100 variant were low-penetrant risk factors for developing breast cancer. Further, no significant associations existed between LEPR rs8179183, rs4655537, and rs3762274 polymorphisms and risk of breast cancer.
Assuntos
Neoplasias da Mama , Estudos de Associação Genética , Receptores para Leptina/genética , Alelos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de RiscoRESUMO
Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective therapy for B-cell acute lymphoblastic leukemia (B-ALL). Although allo-HSCT can be curative for some B-ALL patients, relapse still occurs in some patients following allo-HSCT. Conventional chemotherapies show poor efficacy in B-ALL patients who have relapsed following allo-HSCT. In the past decade, chimeric antigen receptor T-cell (CAR-T) therapy has shown to be efficacious for B-ALL patients. In particular, autologous CD19 CAR-T therapy results in a high remission rate. However, there are challenges in the use of CD19 CAR-T therapy for B-ALL patients who have relapsed following allo-HSCT, including the selection of CAR-T cell source for manufacturing, post-CAR-T graft-versus-host disease (GVHD) risk, maintenance of long-term efficacy after remission through CAR-T therapy, and whether a consolidative second transplant is needed. In this review, we describe the current status of CAR-T therapy for B-ALL patients who have relapsed following allo-HSCT, the advantages and disadvantages of various CAR-T cell sources, the characteristics and management of GVHD following CAR-T therapy, and the risk factors that may affect long-term efficacy.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Receptores de Antígenos Quiméricos , Antígenos CD19 , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapiaRESUMO
Non-small cell lung cancer (NSCLC) ranks first among cancer death worldwide. Despite efficacy and safety priority, targeted therapy only benefits â¼30% patients, leading to the unchanged survival rates for whole NSCLC patients. Metabolic reprogramming occurs to offer energy and intermediates for fuelling cancer cells proliferation. Thus, mechanistic insights into metabolic reprogramming may shed light upon NSCLC proliferation and find new proper targets for NSCLC treatment. Herein, we used loss- and gain-of-function experiments to uncover that highly expressed aldo-keto reductase family1 member C1 (AKR1C1) accelerated NSCLC cells proliferation via metabolic reprogramming. Further molecular profiling analyses demonstrated that AKR1C1 augmented the expression of hypoxia-inducible factor 1-alpha (HIF-1α), which could drive tumour metabolic reprogramming. What's more, AKR1C1 significantly correlated with HIF-1α signaling, which predicted poor prognosis for NSCLC patients. Collectively, our data display that AKR1C1 reprograms tumour metabolism to promote NSCLC cells proliferation by activating HIF-1α. These newly acquired data not only establish the specific role for AKR1C1 in metabolic reprogramming, but also hint to the possibility that AKR1C1 may be a new therapeutic target for NSCLC treatment.
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The molecular basis for induction of apoptosis in melanoma cells by vincristine remains unknown. Here we tested the potential involvement of AMP-activated protein kinase (AMPK) in this process. We found for the first time that vincristine induces AMPK activation (AMPKα, Thr 172) and Acetyl-CoA carboxylase (ACC, Ser 79) (a downstream molecular target of AMPK) phosphorylation in cultured melanoma cells in vitro. Reactive oxygen species (ROS) dependent LKB1 activation serves as the upstream signal for AMPK activation. AMPK inhibitor (compound C) or AMPKα siRNA knockdown inhibits vincristine induced B16 melanoma cell apoptosis, while AMPK activator 5-aminoimidazole-4-carboxamide-1-ß-riboside (AICAR) enhances it. AMPK activation is involved in vincristine induced p53 phosphorylation and stabilization, the latter is known to mediate melanoma cell apoptosis. Further, activation of AMPK by vincristine inhibits mTOR Complex 1 (mTORC1) in B16 melanoma cells, which serves as another important mechanism to induce melanoma cell apoptosis. Our study provides new insights into understanding the cellular and molecular mechanisms of vincristine induced cancer cell death/apoptosis. We suggest that combining AMPK activator AICAR with vincristine may have potential to be used as a new therapeutic intervention against melanoma.
Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Melanoma Experimental/enzimologia , Vincristina/farmacologia , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/genética , Acetil-CoA Carboxilase/metabolismo , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Ativação Enzimática , Ativadores de Enzimas/farmacologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Melanoma Experimental/genética , Melanoma Experimental/patologia , Camundongos , Complexos Multiproteicos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/metabolismo , Pirazóis/farmacologia , Pirimidinas/farmacologia , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Ribonucleotídeos/farmacologia , Serina-Treonina Quinases TOR , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Ginkgo biloba extract (EGb761) has been shown to be neuroprotective; however, the mechanism by which EGb761 mediates neuroprotection remains unclear. We hypothesized that the neuroprotective effect of EGb761 is mediated by inhibition of cytosolic phospholipase A(2) (cPLA(2)), an enzyme that is known to play a key role in mediating secondary pathogenesis after acute spinal cord injury (SCI). To determine whether EGb761 neuroprotection involves the cPLA(2) pathway, we first investigated the effect of glutamate and hydrogen peroxide on cPLA(2) activation. Results showed that both insults induced an increase in the expression of phosphorylated cPLA(2) (p-cPLA(2)), a marker of cPLA(2) activation, and neuronal death in vitro. Such effects were significantly reversed by EGb761 administration. Additionally, EGb761 significantly decreased prostaglandin E(2) (PGE(2)) release, a downstream metabolite of cPLA(2). Moreover, inhibition of cPLA(2) activity with arachidonyl trifluromethyl ketone improved neuroprotection against glutamate and hydrogen peroxide-induced neuronal death, and reversed Bcl-2/Bax ratio; notably, EGb761 produced greater effects than arachidonyl trifluromethyl ketone. Finally, we showed that the extracellular signal-regulated kinase 1/2 signaling pathway is involved in EGb761's modulation of cPLA(2) phosphorylation. These results collectively suggest that the protective effect of EGb761 is mediated, at least in part, through inhibition of cPLA(2) activation, and that the extracellular signal-regulated kinase 1/2 signaling pathway may play an important role in mediating the EGb761's effect.
Assuntos
Ácido Glutâmico/toxicidade , Neurônios/efeitos dos fármacos , Neurotoxinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fosfolipases A2 Citosólicas/metabolismo , Extratos Vegetais/farmacologia , Medula Espinal/citologia , Animais , Animais Recém-Nascidos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ginkgo biloba , Peróxido de Hidrogênio/farmacologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
Trinucleotide repeat containing 9 (TNRC9) is a gene located at chromosome 16q12. Although of an uncertain function, it is a newly described risk factor for breast cancer. It contains a putative high-mobility group box motif, suggesting its possible role as transcription factor; it has been implicated in breast cancer metastasis. Published studies on the association between TNRC9 polymorphisms and breast cancer risk remain inconclusive, and a meta-analysis is required to verify the association. This pioneering research performed a meta-analysis of eight studies comprising a total of 25,828 cases and 36,177 controls. Significantly elevated breast cancer risk was associated with TNRC9 rs3803662 polymorphism when all studies were pooled in the meta-analysis (T vs. C allele contrast model: OR 1.18, 95% CI 1.09-1.28; TT vs. CC homozygote codominant model: OR 1.26, 95% CI 1.02-1.55; TT vs. CC+CT recessive model: OR 1.23, 95% CI 1.06-1.42). For TNRC9 rs12443621 polymorphism, no significant association was detected in all genetic models. For TNRC9 rs12443621 polymorphism, meanwhile, no significant association was observed in all comparison models. Conclusively, this meta-analysis suggests that TNRC9 rs3803662 polymorphism was significantly correlated with breast cancer risk and the variant T allele of TNRC9 rs3803662 polymorphism is a low-penetrant risk factor for developing breast cancer. There is no significant association between TNRC9 rs12443621 and rs8051542 polymorphisms and risk of breast cancer in current literature.
Assuntos
Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Progesterona/genética , Proteínas Reguladoras de Apoptose , Neoplasias da Mama/patologia , Feminino , Proteínas de Grupo de Alta Mobilidade , Humanos , Metanálise como Assunto , Prognóstico , Fatores de Risco , TransativadoresRESUMO
Epidemiological studies have evaluated the association between ataxia telangiectasia mutated (ATM) gene polymorphisms and breast cancer risk. However, published data are still inconclusive. We performed a meta-analysis for the first time, based on currently available evidence, by searching PubMed, ISI Web of Knowledge, and Embase databases to derive a more precise assessment of the relationship. Following the inclusion and exclusion criteria, nine publications were included in this meta-analysis. Of these studies, one had a deviation from the Hardy-Weinberg equilibrium (HWE) at a statistical significance level of 0.01 in controls, and another two had no available data for HWE. We observed that the ATM 5557G>A polymorphism was significantly correlated with breast cancer risk when all studies were pooled into the meta-analysis (recessive model: odds ratio, OR = 0.67; 95% confidence interval (CI) 0.51-0.89). For the ATM IVS38-8T>C polymorphism, no significant association was found in the allele contrast, heterozygote codominant, and dominant models. There were no available data to perform this meta-analysis in the homozygote codominant and recessive models. For the ATM IVS1+19A>T polymorphism, a significant association with breast cancer risk was found in the allele contrast model (C vs. T: OR = 1.60; 95% CI 1.02-2.52). For the IVS34+60G>A polymorphism, no significant association was found in the allele contrast, codominant, dominant, and recessive models. Egger's test did not suggest any evidence of publication bias (P = 0.47 for the recessive model). In conclusion, there is limited evidence to indicate that ATM polymorphisms are associated with increased risk of breast cancer.
Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Predisposição Genética para Doença , Polimorfismo Genético/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética , Proteínas Mutadas de Ataxia Telangiectasia , Neoplasias da Mama/patologia , Feminino , Humanos , Metanálise como Assunto , Prognóstico , Medição de Risco , Fatores de Risco , Taxa de SobrevidaRESUMO
Previous epidemiological studies have evaluated the association between the ABCB1 polymorphism and the risk of breast cancer with conflicting results. Hence, we conducted a meta-analysis of the ABCB1 gene and risk of breast cancer to obtain the most reliable estimate of the association. PubMed, Embase, and Web of Science databases were searched. A total of eight studies including 3,829 cases and 6,193 controls were identified. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were extracted and pooled to assess the strength of associations between the ABCB1 C3435T and rs2214102 G>A polymorphisms and risk of breast cancer. Of these studies, only one deviated from Hardy-Weinberg equilibrium. Summary estimates indicated that the ABCB1 C3435T polymorphism was not associated with increased risk of breast cancer in the allele contrast model (T vs. C, pooled OR = 1.15; 95% CI = 0.89-1.48); the co-dominant model (CT vs. CC, OR = 1.12 [0.86-1.46] and TT vs. CC, OR = 1.30 [0.79-2.15]); the dominant model (OR = 0.80 [0.63-1.02]; and the recessive model (OR = 0.83 [0.57-1.22]). In the sensitivity analysis by ethnicity, no statistically significant associations were detected in Asians. However, in Caucasian women the T allele contrast model and the TT genotype were each associated with increased risk: T vs. C, pooled OR (95% CI) = 1.26 (1.04-1.52) and TT vs. CC, OR = 1.48 (1.04-2.11). Accordingly, the dominant model yielded statistically significant results (pooled OR = 0.71, 95% CI: 0.52-0.96) but not with the allele contrast model or the co-dominant model. There was evidence of publication bias (P = 0.02 for recessive model). In conclusion, there is limited evidence to indicate that the ABCB1 C3435T and rs2214102 G>A polymorphisms are associated with increased risk of breast cancer.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Povo Asiático , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etnologia , Feminino , Frequência do Gene , Genótipo , Humanos , Razão de Chances , Risco , Fatores de Risco , População BrancaRESUMO
Published data on the association between mitogen-activated protein kinase kinase kinase 1 (MAP3K1) gene rs889312 polymorphism and breast cancer risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. Crude ORs with 95% CIs were used to assess the strength of association between them. A total of seven eligible articles including 26,015 cases and 33,962 controls based on the search criteria were involved in this meta-analysis. We observed that the MAP3K1 rs889312 polymorphism was significantly correlated with breast cancer risk from the fixed effects model when all studies were pooled into the meta-analysis (the allele contrast model: OR 1.09, 95% CI 1.07-1.12; the homozygote codominant: OR 1.22, 95% CI 1.15-1.29; the heterozygote codominant: OR 1.07, 95% CI 1.04-1.11; the dominant model: OR 1.10, 95% CI 1.06-1.13; the recessive model: OR 1.18, 95% CI 1.12-1.25). No significant association was found in the BRCA1 mutation carriers in all genetic models. When stratified by BRCA2 mutation carriers status, statistically significantly elevated risk was found in this meta-analysis (C vs. A: OR 1.12, 95% CI 1.01-1.23; CC vs. AA: OR 1.35, 95% CI 1.06-1.71; the recessive model: OR 1.31, 95% CI 1.05-1.65). There was no evidence for significant association between MAP3K1 rs889312 polymorphism and breast cancer risk in BRCA1 and BRCA2 positive cohort for all comparison models. In conclusion, this meta-analysis suggests that the MAP3K1 rs889312 C allele is a low-penetrant risk factor for developing breast cancer, and there is limited evidence to indicate that MAP3K1 rs889312 polymorphism is associated with increased risk of breast cancer in BRCA1 mutation carriers.
Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Genes BRCA1 , MAP Quinase Quinase Quinase 1/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Pessoa de Meia-Idade , Modelos Estatísticos , Razão de Chances , Prognóstico , Risco , Sensibilidade e EspecificidadeRESUMO
The aim of our meta-analysis was to assess the association between UGT1A7 polymorphisms and cancer risk. Case?control studies containing available polymorphic alleles (UGT1A7*1,*2,*3, and*4) and genotypes categorized according to enzymatic activity (High, Intermediate, and Low) were chosen to assess this association. Twenty-one case?control studies were identified. Meta-analysis indicated that UGT1A7 had a significant effect on cancer risk. In subgroup analysis, a significantly increased risk was associated with East Asians, hepatocellular cancer, and colorectal cancer. This meta-analysis suggested that there is a cancer risk associated with UGT1A7*3, Intermediate, and Low activity UGT1A7 genotypes, which is most evident in Asian individuals.