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1.
Chem Res Toxicol ; 28(8): 1574-83, 2015 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-26203587

RESUMO

Tanshinone IIA (TIIA) extracted from Salvia miltiorrhiza has been shown to possess antitumor and TRAIL-sensitizing activity. The involvement of DR5 in the mechanism whereby TIIA exerts its effects is unknown. This study aimed to explore the mechanism underlying TIIA augmentation of TRAIL-induced cell death in ovarian carcinoma cells. Cell viability was determined by MTS assay. Real-time RT-PCR and Western blotting were used to assess the mRNA and protein expression of relating signaling proteins. Transcriptional activation was explored by a dual-luciferase reporter assay. We found that TIIA sensitized human ovarian carcinoma cells to TRAIL-induced extrinsic apoptosis. Combined treatment with subtoxic concentrations of TIIA and TRAIL was more effective than single treatments with respect to cytotoxicity, clonogenic inhibition, and the induction of caspase-8 and PARP activity in ovarian carcinoma cell lines TOV-21G and SKOV3. TIIA induced DR5 protein and mRNA expression in a concentration-dependent manner. DR5/Fc treatment markedly suppressed the TRAIL cytotoxicity enhanced by TIIA. These results indicate that DR5 plays an essential role in TIIA-induced TRAIL sensitization and that induction of DR5 by TIIA is mediated through the up-regulation of CCAAT/enhancer-binding protein homologous protein (CHOP). Knockdown of CHOP gene expression by shRNA attenuated DR5 up-regulation and rescued cell viability under the treatment of TIIA-TRAIL combination. TIIA promoted JNK-mediated signaling to up-regulated CHOP and thereby inducing DR5 expression as shown by the ability of a JNK inhibitor to potently suppress the TIIA-mediated activation of CHOP and DR5. In addition, the quenching of ROS using NAC prevented the induction of JNK phosphorylation and CHOP induction. Furthermore, inhibition of ROS by NAC significantly attenuated TRAIL sensitization by TIIA. Taken together, these data suggest that TIIA enhances TRAIL-induced apoptosis by upregulating DR5 receptors through the ROS-JNK-CHOP signaling axis in human ovarian carcinoma cells.


Assuntos
Abietanos/farmacologia , Sistema de Sinalização das MAP Quinases , Espécies Reativas de Oxigênio/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Fator de Transcrição CHOP/metabolismo , Regulação para Cima/efeitos dos fármacos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Modelos Biológicos , Neoplasias Ovarianas/tratamento farmacológico , Reação em Cadeia da Polimerase em Tempo Real , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Transdução de Sinais/efeitos dos fármacos
2.
Artigo em Inglês | MEDLINE | ID: mdl-36900859

RESUMO

Stroke patients presenting with anemia at the time of stroke onset had a higher risk of mortality and development of other cardiovascular diseases and comorbidities. The association between the severity of anemia and the risk of developing a stroke is still uncertain. This retrospective study aimed to evaluate the association between stroke incidence and anemia severity (by WHO criteria). A total of 71,787 patients were included, of whom 16,708 (23.27%) were identified as anemic and 55,079 patients were anemia-free. Female patients (62.98%) were more likely to have anemia than males (37.02%). The likelihood of having a stroke within eight years after anemia diagnosis was calculated using Cox proportional hazard regression. Patients with moderate anemia had a significant increase in stroke risk compared to the non-anemia group in univariate analyses (hazard ratios [HR] = 2.31, 95% confidence interval [CI], 1.97-2.71, p < 0.001) and in adjusted HRs (adj-HR = 1.20, 95% CI, 1.02-1.43, p = 0.032). The data reveal that patients with severe anemia received more anemia treatment, such as blood transfusion and nutritional supplementation, and maintaining blood homeostasis may be important to preventing stroke. Anemia is an important risk factor, but other risk factors, including diabetes and hyperlipidemia, also affect stroke development. There is a heightened awareness of anemia's severity and the increasing risk of stroke development.


Assuntos
Anemia , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Estudos Retrospectivos , Anemia/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Incidência
3.
Toxicol Appl Pharmacol ; 265(3): 325-34, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22982536

RESUMO

Prodigiosin is a bacterial tripyrrole pigment with potent cytotoxicity against diverse human cancer cell lines. Endoplasmic reticulum (ER) stress is initiated by accumulation of unfolded or misfolded proteins in the ER lumen and may induce cell death when irremediable. In this study, the role of ER stress in prodigiosin-induced cytotoxicity was elucidated for the first time. Comparable to the ER stress inducer thapsigargin, prodigiosin up-regulated signature ER stress markers GRP78 and CHOP in addition to activating the IRE1, PERK and ATF6 branches of the unfolded protein response (UPR) in multiple human breast carcinoma cell lines, confirming prodigiosin as an ER stress inducer. Prodigiosin transcriptionally up-regulated CHOP, as evidenced by its promoting effect on the CHOP promoter activity. Of note, knockdown of CHOP effectively lowered prodigiosin's capacity to evoke PARP cleavage, reduce cell viability and suppress colony formation, highlighting an essential role of CHOP in prodigiosin-induced cytotoxic ER stress response. In addition, prodigiosin down-regulated BCL2 in a CHOP-dependent manner. Importantly, restoration of BCL2 expression blocked prodigiosin-induced PARP cleavage and greatly enhanced the survival of prodigiosin-treated cells, suggesting that CHOP-dependent BCL2 suppression mediates prodigiosin-elicited cell death. Moreover, pharmacological inhibition of JNK by SP600125 or dominant-negative blockade of PERK-mediated eIF2α phosphorylation impaired prodigiosin-induced CHOP up-regulation and PARP cleavage. Collectively, these results identified ER stress-mediated cell death as a mode-of-action of prodigiosin's tumoricidal effect. Mechanistically, prodigiosin engages the IRE1-JNK and PERK-eIF2α branches of the UPR signaling to up-regulate CHOP, which in turn mediates BCL2 suppression to induce cell death.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Prodigiosina/farmacologia , Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/fisiologia , Endorribonucleases/genética , Endorribonucleases/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Immunoblotting , Células MCF-7 , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , RNA/química , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Resposta a Proteínas não Dobradas , Regulação para Cima/efeitos dos fármacos , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
4.
J Patient Saf ; 18(5): 475-485, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121722

RESUMO

OBJECTIVE: Patients undergoing hemodialysis are a high-risk population. This study identified possible errors by using a healthcare failure mode and effect analysis system to improve patient safety during hemodialysis. METHODS: A multidisciplinary collaborative team, including physicians, nurses, information technicians, and medical staff members, was assembled. A flow diagram was used to indicate each process of the hemodialysis procedure from evaluating patient condition to transporting the patient back to the ward from the hemodialysis center. We scored all possible failure modes using the hazard scoring method as a combination of the occurrence frequency and severity. These potential failure modes were used to identify and evaluate possible risks by using a risk scoring matrix. RESULTS: Thirty failure modes were identified across 6 processes, and their potential causes were explored. Four major strategies for addressing most of the failure modes were implemented: establishment of a mobile application that sends real-time automated alerts to the medical team based on the Modified Early Warning Score, design of a modified dialysis Identify-Situation-Background-Assessment-Recommendation checklist for dialysis, technician education and training, and internal auditing and monitoring of the implementation of the entire process. After the implementation of the strategies, the hazard scores of patients during dialysis dropped by 71.2% from 170 points to 49 points. CONCLUSIONS: The healthcare failure mode and effect analysis system was useful for evaluating potential risk during dialysis. Using the mobile application reduced the occurrence of emergency resuscitation during hemodialysis and significantly improved the communication between medical personnel.


Assuntos
Escore de Alerta Precoce , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Aplicativos Móveis , Humanos , Segurança do Paciente , Diálise Renal
5.
J Patient Saf ; 16(4): e303-e309, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33215894

RESUMO

OBJECTIVES: In our hospital's hemovigilance system, a Wi-Fi-based vital signs monitor that automatically transmits data to ensure patient safety has been implemented. We derived the potential clinical characteristics for subsequent association of acute transfusion reactions (ATRs) using the hospital information system database. METHODS: We retrospectively analyzed multiple factors to identify the possible associations between clinical factors and developing ATRs. The following data were collected: recipient's pretransfusion and posttransfusion vital signs, clinical and laboratory characteristics, and presence of ATRs. RESULTS: In all, 44,691 events were analyzed. Of these, ATR events occurred in 1586 (3.5%). Logistic regression analysis revealed that leukopenia (<5×10/µL) before transfusion was shown a statistically associated with developing mild ATRs (odds ratio [OR] = 2.38, 95% confidence interval [CI] = 1.68-3.35, P < 0.001). The association between elevated body temperature (forehead temperature > 37.5°C) and moderate ATRs was significant (OR = 1.55, 95% CI = 1.22-1.98, P < 0.001). In addition, the association between high diastolic pressure (>90 mm Hg) and severe ATRs was significant (OR = 1.78, 95% CI = 1.06-2.99, P = 0.03). Therefore, evaluated patient's status such as vital signs before transfusion is very important. In addition, every hospital should established a complete hemovigilance program focus on effectively reporting and real-time monitoring ATRs to improve transfusion patient safety. CONCLUSIONS: Vital signs monitoring and leukocyte counts before transfusion were significantly associated with the subsequent risk of ATRs. When patients with elevated body temperature, leukopenia, and high diastolic pressure who are scheduled to receive transfusion, clinicians should be aware of increasing the risk of ATRs in these patients.


Assuntos
Erros Médicos/tendências , Reação Transfusional/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Hospitais , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
6.
Toxicol Appl Pharmacol ; 235(2): 253-60, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19133282

RESUMO

Prodigiosin is a bacterial metabolite with potent anticancer activity, which is attributed to its proapoptotic effect selectively active in malignant cells. Still, the molecular mechanisms whereby prodigiosin induces apoptosis remain largely unknown. In particular, the role of survivin, a vital inhibitor of apoptosis, in prodigiosin-induced apoptosis has never been addressed before and hence was the primary goal of this study. Our results showed that prodigiosin dose-dependently induced down-regulation of survivin in multiple breast carcinoma cell lines, including MCF-7, T-47D and MDA-MB-231. This down-regulation is mainly regulated at the level of transcription, as prodigiosin reduced the levels of both survivin mRNA and survivin promoter activity but failed to rescue survivin expression when proteasome-mediated degradation is abolished. Importantly, overexpression of survivin rendered cells more resistant to prodigiosin, indicating an essential role of survivin down-regulation in prodigiosin-induced apoptosis. In addition, we found that prodigiosin synergistically enhanced cell death induced by paclitaxel, a chemotherapy drug known to up-regulate survivin that in turn confers its own resistance. This paclitaxel sensitization effect of prodigiosin is ascribed to the lowering of survivin expression, because prodigiosin was shown to counteract survivin induction by paclitaxel and, notably, the sensitization effect was severely abrogated in cells that overexpress survivin. Taken together, our results argue that down-regulation of survivin is an integral component mediating prodigiosin-induced apoptosis in human breast cancer cells, and further suggest the potential of prodigiosin to sensitize anticancer drugs, including paclitaxel, in the treatment of breast cancer.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/patologia , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Paclitaxel/farmacologia , Prodigiosina/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Genes Reporter/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose , Luciferases/genética , Luciferases/metabolismo , Plasmídeos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Survivina , Ensaio Tumoral de Célula-Tronco
7.
Materials (Basel) ; 9(9)2016 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28773912

RESUMO

To accelerate healing of severe hemorrhagic wounds, a novel highly absorbent hemostatic dressing composed of a Tencel®/absorbent-cotton/polylactic acid nonwoven base and chitosan/nanosilver antibacterial agent was fabricated by using a nonwoven processing technique and a freeze-drying technique. This study is the first to investigate the wicking and water-absorbing properties of a nonwoven base by measuring the vertical wicking height and water absorption ratio. Moreover, blood agglutination and hemostatic second tests were conducted to evaluate the hemostatic performance of the resultant wound dressing. The blending ratio of fibers, areal weight, punching density, and fiber orientation, all significantly influenced the vertical moisture wicking property. However, only the first two parameters markedly affected the water absorption ratio. After the nonwoven base absorbed blood, scanning electron microscope (SEM) observation showed that erythrocytes were trapped between the fibrin/clot network and nonwoven fibers when coagulation pathways were activated. Prothrombin time (PT) and activated partial thromboplastin time (APTT) blood agglutination of the resultant dressing decreased to 14.34 and 50.94 s, respectively. In the femoral artery of the rate bleeding model, hemostatic time was saved by 87.2% compared with that of cotton cloth. Therefore, the resultant antibacterial wound dressing demonstrated greater water and blood absorption, as well as hemostatic performance, than the commercially available cotton cloth, especially for healing severe hemorrhagic wounds.

8.
Biomedicine (Taipei) ; 5(4): 23, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26621311

RESUMO

An ideal cancer therapy specifically targets cancer cells while sparing normal tissues. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) elicits apoptosis by engaging its cognate death receptors (DRs-namely, DR4 and DR5. The cancer cell-selective proapoptotic action of TRAIL is highly attractive for cancer therapy, but clinical application of TRAIL is rather limited due to tumors' inherent or acquired TRAIL resistance. Combining TRAIL with agents that reverse resistance to it has proved promising in the sensitization of TRAIL-induced apoptosis. Noteworthy, natural compounds have already been validated as potential resources for TRAIL sensitizers. In this review, we focus on the recently identified TRAILsensitizing effect of tanshinones, the anticancer ingredients of the medicinal plant Salvia miltiorrhiza (Danshen in Chinese). Research from our laboratories and others have revealed the synergy of a tanshinones-TRAIL combination in diverse types of cancer cells through up-regulation of DR5 and/or down-regulation of antiapoptotic proteins such as survivin. Thus, in addition to their anticancer mechanisms, tanshinones as TRAIL sensitizers hold great potential to be translated to TRAIL-based therapeutic modalities for combatting cancer.

9.
Phytomedicine ; 22(10): 929-38, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26321742

RESUMO

BACKGROUND: Tanshinone IIA (TIIA), a diterpene quinone from the medicinal plant Salvia miltiorrhiza Bunge (Lamiaceae) was shown to possess apoptotic and TRAIL-sensitizing effects. Still, the molecular mechanisms whereby TIIA induces apoptosis remain largely unknown. PURPOSE: The role of survivin, an inhibitor of apoptosis protein, in TIIA-induced apoptosis has never been addressed before and hence was the primary goal of this study. METHODS: In this study, we explored the anticancer effect of TIIA in TOV-21G, SKOV3, and OVCAR3 ovarian carcinoma cells. Cytotoxicity was determined by MTS assay. Real-time RT-PCR and Western blotting were used to assess the mRNA and protein expression of related signaling proteins. RESULTS: Our results illustrated that TIIA's cytotoxic effect was caused by apoptosis with the involvement of caspases activity. Moreover, TIIA downregulated survivin in a concentration-dependent manner without affecting the expression of Bcl-2, Bcl-xL, and Bax. TIIA-induced survivin downregulation is regulated by both transcriptional processes and proteasomal degradation. Using TOV-21G cells as our cellular model, we demonstrated that TIIA-induced survivin downregulation requires p38 MAPK activation. Importantly, genetic overexpression of survivin rendered cells more resistant to TIIA, indicating an essential role of survivin downregulation in TIIA-induced apoptosis. This TRAIL sensitization effect of TIIA is ascribed to survivin downregulation because the effect was abrogated in cells that overexpressed survivin. CONCLUSION: Our findings provide new insights into the action modes of TIIA-mediated anticancer effects and further implicate a rational design for cancer therapeutic regimens by combining TIIA-sensitized TRAIL via downregulating survivin to elicit ovarian cancer cell death.


Assuntos
Abietanos/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Ovarianas/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Linhagem Celular Tumoral/efeitos dos fármacos , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Survivina
10.
J Biosci Bioeng ; 116(4): 516-23, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23660075

RESUMO

Natural compounds isolated from medicinal plants are invaluable resources for drug discovery. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising anticancer agent unique by its cancer cell-specific proapoptotic action, but its potential is heavily curbed by acquired resistance. We herein reported for the first time the identification of cytotoxic and TRAIL-sensitizing components of Salvia miltiorrhiza (Danshen), a traditional medicinal plant effective for treating cardiovascular disorders. Specifically, we found that the ethanol extract and its group 5 fraction of S. miltiorrhiza showed evident cytotoxicity against the human lung adenocarcinoma cell line A549 and ovarian adenocarcinoma cell line TOV-21G in a concentration-dependent manner. Likewise, a dose-dependent cytotoxicity was exerted by the standard solutions of cryptotanshinone, tanshinone I and tanshinone IIA, the major components of the group 5 fraction, where tanshinone IIA were most potent and displayed an IC50 of 2.00 ± 0.36 µM and 2.75 ± 0.23 µM for A549 and TOV-21G, respectively. Induction of apoptosis represents an essential mechanism underlying tanshinone IIA-mediated cytotoxic action, as evidenced by the proteolytic processing of PARP upon tanshinone IIA stimulation and, importantly, a marked rescue of the viability of tanshinone IIA-treated cells when co-treatment with the pan-caspase inhibitor z-VAD-fmk. Noteworthy, stimulation with cryptotanshinone, tanshinone I or tanshinone IIA all effectively potentiated TRAIL to reduce viability and inhibit the colony formation capacity of TRAIL-resistant TOV-21G and SKOV3. Collectively, we revealed the proapoptotic and TRAIL-sensitizing components of S. miltiorrhiza and further implicated the potential of developing these active compounds as monotherapeutic agent or TRAIL-based therapy for cancer chemoprevention or chemotherapy.


Assuntos
Apoptose/efeitos dos fármacos , Medicamentos de Ervas Chinesas/química , Neoplasias/metabolismo , Neoplasias/patologia , Fenantrolinas/química , Extratos Vegetais/química , Salvia miltiorrhiza/química , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Abietanos/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Inibidores de Caspase/farmacologia , Divisão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/farmacologia , Feminino , Humanos , Concentração Inibidora 50 , Neoplasias/tratamento farmacológico , Neoplasias/enzimologia , Fenantrenos/farmacologia , Fenantrolinas/farmacologia , Extratos Vegetais/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/agonistas
11.
Artigo em Inglês | MEDLINE | ID: mdl-23573140

RESUMO

Subamolide B is a butanolide isolated from Cinnamomum subavenium, a medicinal plant traditionally used to treat various ailments including carcinomatous swelling. We herein reported for the first time that subamolide B potently induced cytotoxicity against diverse human skin cancer cell lines while sparing nonmalignant cells. Mechanistic studies on human cutaneous squamous cell carcinoma (SCC) cell line SCC12 highlighted the involvement of apoptosis in subamolide B-induced cytotoxicity, as evidenced by the activation of caspases-8, -9, -4, and -3, the increase in annexin V-positive population, and the partial restoration of cell viability by cotreatment with the pan-caspase inhibitor z-VAD-fmk. Additionally, subamolide B evoked cell death pathways mediated by FasL/Fas, mitochondria, and endoplasmic reticulum (ER) stress, as supported by subamolide B-induced FasL upregulation, BCL-2 suppression/cytosolic release of cytochrome c, and UPR activation/CHOP upregulation, respectively. Noteworthy, ectopic expression of c-FLIPL or dominant-negative mutant of FADD failed to impair subamolide B-induced cytotoxicity, whereas BCL-2 overexpression or CHOP depletion greatly rescued subamolide B-stimulated cells. Collectively, these results underscored the central role of mitochondrial and CHOP-mediated cell death pathways in subamolide B-induced cytotoxicity. Our findings further implicate the potential of subamolide B for cutaneous SCC therapy or as a lead compound for developing novel chemotherapeutic agents.

12.
J Biosci Bioeng ; 111(5): 501-11, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21277252

RESUMO

Discoveries of tumor-resistant pharmacological drugs have mainly resulted from screening of natural products and their analogs. Some are also discovered incidentally when studying organisms. The great biodiversity of microorganisms raises the possibility of producing secondary metabolites (e.g., mevastatin, lovastatin, epothilone, salinosporamide A) to cope with adverse environments. Recently, natural plant pigments with anti-tumor activities such as ß-carotene, lycopene, curcumin and anthocyanins have been proposed. However, many plants have a long life cycle. Therefore, pigments from microorganisms represent another option for the development of novel anti-tumor drugs. Prodigiosin (PG) is a natural red pigment produced by microorganisms, i.e., Serratia marcescens and other gram-negative bacteria. The anti-tumor potential of PG has been widely demonstrated. The families of PG (PGs), which share a common pyrrolylpyrromethene (PPM) skeleton, are produced by various bacteria. PGs are bioactive pigments and are known to exert immunosuppressive properties, in vitro apoptotic effects, and in vivo anti-tumor activities. Currently the most common strain used for producing PGs is S. marcescens. However, few reports have discussed PGs production. This review therefore describes the development of an anti-tumor drug, PG, that can be naturally produced by microorganisms, and evaluates the microbial production system, fermentation strategies, purification and identification processes. The application potential of PGs is also discussed.


Assuntos
Antineoplásicos/metabolismo , Neoplasias/tratamento farmacológico , Prodigiosina/biossíntese , Serratia marcescens/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose , Reatores Biológicos , Ciclo Celular/efeitos dos fármacos , Meios de Cultura/química , Fermentação , Microbiologia Industrial/métodos , Estrutura Molecular , Prodigiosina/isolamento & purificação , Prodigiosina/farmacologia
13.
Toxicol Appl Pharmacol ; 225(3): 318-28, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17881028

RESUMO

Undecylprodigiosin (UP) is a bacterial bioactive metabolite produced by Streptomyces and Serratia. In this study, we explored the anticancer effect of UP. Human breast carcinoma cell lines BT-20, MCF-7, MDA-MB-231 and T47D and one nonmalignant human breast epithelial cell line, MCF-10A, were tested in this study. We found that UP exerted a potent cytotoxicity against all breast carcinoma cell lines in a dose- and time-dependent manner. In contrast, UP showed limited toxicity to MCF-10A cells, indicating UP's cytotoxic effect is selective for malignant cells. UP's cytotoxic effect was due to apoptosis, as confirmed by positive TUNEL signals, annexin V-binding, caspase 9 activation and PARP cleavage. Notably, UP-induced apoptosis was blocked by the pan-caspase inhibitor z-VAD.fmk, further indicating the involvement of caspase activity. Moreover, UP caused a marked decrease of the levels of antiapoptotic BCL-X(L), Survivin and XIAP while enhancing the levels of proapoptotic BIK, BIM, MCL-1S and NOXA, consequently favoring induction of apoptosis. Additionally, we found that cells with functional p53 (MCF-7, T47D) or mutant p53 (BT-20, MDA-MB-231) were both susceptible to UP's cytotoxicity. Importantly, UP was able to induce apoptosis in MCF-7 cells with p53 knockdown by RNA interference, confirming the dispensability of p53 in UP-induced apoptosis. Overall, our results establish that UP induces p53-independent apoptosis in breast carcinoma cells with no marked toxicity to nonmalignant cells, raising the possibility of its use as a new chemotherapeutic drug for breast cancer irrespective of p53 status.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Proteína Supressora de Tumor p53/metabolismo , Anexina A5/efeitos dos fármacos , Anexina A5/metabolismo , Antineoplásicos/administração & dosagem , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Caspase 9/efeitos dos fármacos , Caspase 9/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas , Proteínas Inibidoras de Apoptose , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Mitocondriais , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteínas de Neoplasias/efeitos dos fármacos , Proteínas de Neoplasias/metabolismo , Poli(ADP-Ribose) Polimerases/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Prodigiosina/administração & dosagem , Prodigiosina/análogos & derivados , Prodigiosina/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Serratia marcescens/química , Survivina , Fatores de Tempo , Proteína Supressora de Tumor p53/efeitos dos fármacos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/efeitos dos fármacos , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Proteína bcl-X/efeitos dos fármacos , Proteína bcl-X/metabolismo
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