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1.
Cell Death Dis ; 15(5): 349, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769167

RESUMO

Osteosarcoma is a malignant bone tumor that primarily inflicts the youth. It often metastasizes to the lungs after chemotherapy failure, which eventually shortens patients' lives. Thus, there is a dire clinical need to develop a novel therapy to tackle osteosarcoma metastasis. Methionine dependence is a special metabolic characteristic of most malignant tumor cells that may offer a target pathway for such therapy. Herein, we demonstrated that methionine deficiency restricted the growth and metastasis of cultured human osteosarcoma cells. A genetically engineered Salmonella, SGN1, capable of overexpressing an L-methioninase and hydrolyzing methionine led to significant reduction of methionine and S-adenosyl-methionine (SAM) specifically in tumor tissues, drastically restricted the growth and metastasis in subcutaneous xenograft, orthotopic, and tail vein-injected metastatic models, and prolonged the survival of the model animals. SGN1 also sharply suppressed the growth of patient-derived organoid and xenograft. Methionine restriction in the osteosarcoma cells initiated severe mitochondrial dysfunction, as evident in the dysregulated gene expression of respiratory chains, increased mitochondrial ROS generation, reduced ATP production, decreased basal and maximum respiration, and damaged mitochondrial membrane potential. Transcriptomic and molecular analysis revealed the reduction of C1orf112 expression as a primary mechanism underlies methionine deprivation-initiated suppression on the growth and metastasis as well as mitochondrial functions. Collectively, our findings unraveled a molecular linkage between methionine restriction, mitochondrial function, and osteosarcoma growth and metastasis. A pharmacological agent, such as SGN1, that can achieve tumor specific deprivation of methionine may represent a promising modality against the metastasis of osteosarcoma and potentially other types of sarcomas as well.


Assuntos
Neoplasias Ósseas , Metionina , Mitocôndrias , Osteossarcoma , Osteossarcoma/patologia , Osteossarcoma/metabolismo , Osteossarcoma/genética , Osteossarcoma/tratamento farmacológico , Metionina/deficiência , Metionina/metabolismo , Humanos , Animais , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Camundongos , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Metástase Neoplásica , S-Adenosilmetionina/metabolismo , S-Adenosilmetionina/farmacologia , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos
2.
PLoS Pathog ; 19(10): e1011694, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37831643

RESUMO

Alongshan virus (ALSV), a newly discovered member of unclassified Flaviviridae family, is able to infect humans. ALSV has a multi-segmented genome organization and is evolutionarily distant from canonical mono-segmented flaviviruses. The virus-encoded methyltransferase (MTase) plays an important role in viral replication. Here we show that ALSV MTase readily binds S-adenosyl-L-methionine (SAM) and S-adenosyl-L-homocysteine (SAH) but exhibits significantly lower affinities than canonical flaviviral MTases. Structures of ALSV MTase in the free and SAM/SAH-bound forms reveal that the viral enzyme possesses a unique loop-element lining side-wall of the SAM/SAH-binding pocket. While the equivalent loop in flaviviral MTases half-covers SAM/SAH, contributing multiple hydrogen-bond interactions; the pocket-lining loop of ALSV MTase is of short-length and high-flexibility, devoid of any physical contacts with SAM/SAH. Subsequent mutagenesis data further corroborate such structural difference affecting SAM/SAH-binding. Finally, we also report the structure of ALSV MTase bound with sinefungin, an SAM-analogue MTase inhibitor. These data have delineated the basis for the low-affinity interaction between ALSV MTase and SAM/SAH and should inform on antiviral drug design.


Assuntos
Flavivirus , Metiltransferases , Humanos , Metiltransferases/genética , Flavivirus/genética , Flavivirus/metabolismo , S-Adenosilmetionina/metabolismo , Mutagênese
3.
Eur Radiol ; 33(11): 7857-7865, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37338557

RESUMO

OBJECTIVES: To determine the contribution of a modified definition of markedly hypoechoic in the differential diagnosis of thyroid nodules. METHODS: A total of 1031 thyroid nodules were included in this retrospective multicenter study. All of the nodules were examined with US before surgery. The US features of the nodules were evaluated, in particular, the classical markedly hypoechoic and modified markedly hypoechoic (decreased or similar echogenicity relative to the adjacent strap muscles). The sensitivity, specificity, and AUC of classical/modified markedly hypoechoic and the corresponding ACR-TIRADS, EU-TIRADS, and C-TIRADS categories were calculated and compared. The inter- and intraobserver variability in the evaluation of the main US features of the nodules was assessed. RESULTS: There were 264 malignant nodules and 767 benign nodules. Compared with classical markedly hypoechoic as a diagnostic criterion for malignancy, using modified markedly hypoechoic as the criterion resulted in a significant increase in sensitivity (28.03% vs. 63.26%) and AUC (0.598 vs. 0.741), despite a significant decrease in specificity (91.53% vs. 84.88%) (p < 0.001 for all). Compared to the AUC of the C-TIRADS with the classical markedly hypoechoic, the AUC of the C-TIRADS with the modified markedly hypoechoic increased from 0.878 to 0.888 (p = 0.01); however, the AUCs of the ACR-TIRADS and EU-TIRADS did not change significantly (p > 0.05 for both). There was substantial interobserver agreement (κ = 0.624) and perfect intraobserver agreement (κ = 0.828) for the modified markedly hypoechoic. CONCLUSION: The modified definition of markedly hypoechoic resulted in a significantly improved diagnostic efficacy in determining malignant thyroid nodules and may improve the diagnostic performance of the C-TIRADS. CLINICAL RELEVANCE STATEMENT: Our study found that, compared with the original definition, modified markedly hypoechoic significantly improved the diagnostic performance in differentiating malignant from benign thyroid nodules and the predictive efficacy of the risk stratification systems. KEY POINTS: • Compared with the classical markedly hypoechoic as a diagnostic criterion for malignancy, the modified markedly hypoechoic resulted in a significant increase in sensitivity and AUC. • The C-TIRADS with the modified markedly hypoechoic achieved higher AUC and specificity than that with the classical markedly hypoechoic (p = 0.01 and < 0.001, respectively).


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Nódulo da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Ultrassonografia/métodos , Medição de Risco/métodos , Estudos Retrospectivos
4.
ACS Appl Mater Interfaces ; 15(13): 16482-16491, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36972557

RESUMO

Chemodynamic therapy (CDT) relies on the transformation of intracellular hydrogen peroxide (H2O2) to hydroxyl radicals (·OH) with higher toxicity under the catalysis of Fenton/Fenton-like reagents, which amplifies the oxidative stress and induces significant cellular apoptosis. However, the CDT efficacy is generally limited by the overexpressed GSH and insufficient endogenous H2O2 in tumors. Co-delivery of Cu2+ and glucose oxidase (GOD) can lead to a Cu2+/Cu+ circulation to realize GSH depletion and amplify the Fenton-like reaction. pH-responsive metal-organic frameworks (MOFs) are the optical choice to deliver Fenton/Fenton-like ions to tumors. However, considering that the aqueous condition is requisite for GOD encapsulation, it is challenging to abundantly dope Cu2+ in ZIF-8 MOF nanoparticles in aqueous conditions due to the ease of precipitation and enlarged crystal size. In this work, a robust one-pot biomimetic mineralization method using excessive ligand precursors in aqueous conditions is developed to synthesize GOD@Cu-ZIF-8. Copper ions abundantly doped to the GOD@Cu-ZIF-8 can eliminate GSH to produce Cu+, which is further proceeded to the Fenton-like reaction in the presence of GOD-catalyzed H2O2. Through breaking the tumor microenvironment homeostasis and producing an enhanced CDT effect, the promising antitumor capability of GOD@Cu-ZIF-8 was evidenced by the experiments both in vitro and in vivo.


Assuntos
Nanopartículas , Neoplasias , Humanos , Glucose Oxidase , Peróxido de Hidrogênio , Homeostase , Estresse Oxidativo , Linhagem Celular Tumoral , Microambiente Tumoral , Glutationa
5.
Nanomaterials (Basel) ; 13(4)2023 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-36839042

RESUMO

Although colorectal cancer (CRC) is easy to treat surgically and can be combined with postoperative chemotherapy, its five-year survival rate is still not optimistic. Therefore, developing sensitive, efficient, and compliant detection technology is essential to diagnose CRC at an early stage, providing more opportunities for effective treatment and intervention. Currently, the widely used clinical CRC detection methods include endoscopy, stool examination, imaging modalities, and tumor biomarker detection; among them, blood biomarkers, a noninvasive strategy for CRC screening, have shown significant potential for early diagnosis, prediction, prognosis, and staging of cancer. As shown by recent studies, electrochemical biosensors have attracted extensive attention for the detection of blood biomarkers because of their advantages of being cost-effective and having sound sensitivity, good versatility, high selectivity, and a fast response. Among these, nano-conductive polymer materials, especially the conductive polymer polypyrrole (PPy), have been broadly applied to improve sensing performance due to their excellent electrical properties and the flexibility of their surface properties, as well as their easy preparation and functionalization and good biocompatibility. This review mainly discusses the characteristics of PPy-based biosensors, their synthetic methods, and their application for the detection of CRC biomarkers. Finally, the opportunities and challenges related to the use of PPy-based sensors for diagnosing CRC are also discussed.

6.
ACS Appl Mater Interfaces ; 15(9): 11575-11585, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36808954

RESUMO

Chemodynamic therapy (CDT) based on the Fe2+-mediated Fenton reaction can amplify intracellular oxidative stress by producing toxic •OH. However, the high-dose need for Fe2+ delivery in tumors and its significant cytotoxicity to normal tissues set a challenge. Therefore, a controllable delivery to activate the Fenton reaction and enhance Fe2+ tumor accumulation has become an approach to solve this conflict. Herein, we report a rare-earth-nanocrystal (RENC)-based Fe2+ delivery system using light-control techniques and DNA nanotechnology to realize programmable Fe2+ delivery. Ferrocenes, the source of Fe2+, are modified on the surface of RENCs through pH-responsive DNAs, which are further shielded by a PEG layer to elongate blood circulation and "turn off" the cytotoxicity of ferrocene. The up-/down-conversion dual-mode emissions of RENCs endow the delivery system with both capabilities of diagnosis and delivery control. The down-conversion NIR-II fluorescence can locate tumors. Consequently, up-conversion UV light spatiotemporally activates the catalytic activity of Fe2+ by shedding off the protective PEG layer. The exposed ferrocene-DNAs not only can "turn on" Fenton catalytic activity but also respond to tumor acidity, driving cross-linking and enhanced Fe2+ enrichment in tumors by 4.5-fold. Accordingly, this novel design concept will be inspiring for developing CDT nanomedicines in the future.


Assuntos
Metais Terras Raras , Nanopartículas , Neoplasias , Humanos , Luminescência , Fluorescência , Metalocenos , Linhagem Celular Tumoral , Neoplasias/tratamento farmacológico , Peróxido de Hidrogênio , Microambiente Tumoral
7.
Nat Commun ; 13(1): 7948, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572677

RESUMO

Magnetic resonance imaging (MRI) is a non-invasive imaging technology to diagnose health conditions, showing the weakness of low sensitivity. Herein, we synthesize a contrast agent, SPIO@SiO2@MnO2, which shows decreased T1 and T2 contrast intensity in normal physiological conditions. In the acid environment of tumor or inflamed tissue, the manganese dioxide (MnO2) layer decomposes into magnetically active Mn2+ (T1-weighted), and the T1 and T2 signals are sequentially recovered. In addition, both constrast quenching-activation degrees of T1 and T2 images can be accurately regulated by the silicon dioxide (SiO2) intermediate layer between superparamagnetic iron oxide (SPIO) and MnO2. Through the "dual-contrast enhanced subtraction" imaging processing technique, the contrast sensitivity of this MRI contrast agent is enhanced to a 12.3-time difference between diseased and normal tissue. Consequently, SPIO@SiO2@MnO2 is successfully applied to trace the tiny liver metastases of approximately 0.5 mm and monitor tissue inflammation.


Assuntos
Meios de Contraste , Neoplasias Hepáticas , Humanos , Compostos de Manganês , Dióxido de Silício , Óxidos , Imageamento por Ressonância Magnética/métodos , Neoplasias Hepáticas/secundário , Concentração de Íons de Hidrogênio
8.
ACS Appl Mater Interfaces ; 14(28): 31677-31688, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35786850

RESUMO

Magnetic resonance-guided focused ultrasound (MRgFUS) is a promising non-invasive surgical technique with spatial specificity and minimal off-target effects. Despite the expanding clinical applications, the major obstacles associated with MRgFUS still lie in low magnetic resonance imaging (MRI) sensitivity and safety issues. High ultrasound power is required to resist the energy attenuation during the delivery to the tumor site and may cause damage to the surrounding healthy tissues. Herein, a surface modification strategy is developed to simultaneously strengthen MRI and ultrasound ablation of MRgFUS by prolonging Fe3O4 nanoparticles' blood circulation and tumor-environment-triggered accumulation and retention at the tumor site. Specifically, reactive oxygen species-labile methoxy polyethylene glycol and pH-responsive DNA cross-linkers are modified on the surface of Fe3O4 nanoparticles, which can transform nanoparticles into aggregations through the cascade responsive reactions at the tumor site. Notably, DNA is selected as the pH-responsive cross-linker because of its superior biocompatibility as well as the fast and sensitive response to the weak acidity of 6.5-6.8, corresponding to the extracellular pH of tumor tissues. Due to the significantly enhanced delivery and retention amount of Fe3O4 nanoparticles at the tumor site, the MRI sensitivity was enhanced by 1.7-fold. In addition, the ultrasound power was lowered by 35% to reach a sufficient thermal ablation effect. Overall, this investigation demonstrates a feasible resolution to promote the MRgFUS treatment by enhancing the therapeutic efficacy and reducing the side effects, which will be helpful to guide the clinical practice in the future.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Nanopartículas de Magnetita , DNA , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética
9.
Emerg Microbes Infect ; 11(1): 1920-1935, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35757908

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and related sarbecoviruses enter host cells by receptor-recognition and membrane-fusion. An indispensable step in fusion is the formation of 6-helix bundle by viral spike heptad repeats 1 and 2 (HR1 and HR2). Here, we report the construction of 5-helix bundle (5HB) proteins for virus infection inhibition. The optimal construct inhibits SARS-CoV-2 pseudovirus entry with sub-micromolar IC50. Unlike HR2-based peptides that cannot bind spike in the pre-fusion conformation, 5HB features with the capability of binding to pre-fusion spike. Furthermore, 5HB binds viral HR2 at both serological- and endosomal-pH, highlighting its entry-inhibition capacity when SARS-CoV-2 enters via either cell membrane fusion or endosomal route. Finally, we show that 5HB could neutralize S-mediated entry of the predominant SARS-CoV-2 variants and a wide spectrum of sarbecoviruses. These data provide proof-of-concept evidence that 5HB might be developed for the prevention and treatment of SARS-CoV-2 and other emerging sarbecovirus infections.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Concentração de Íons de Hidrogênio , Glicoproteínas de Membrana/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus
10.
Front Nutr ; 9: 1071276, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36726818

RESUMO

Lindera aggregata (Sims) Kosterm. (L. aggregata), which belongs to the genus Lindera in the family Lauraceae, is widely distributed in Asia and the temperate, tropical regions of North America. Its roots and leaves have been used for thousands of years as traditional Chinese medicine and/or functional food. To further explore its underlying nutritional value, this review provided a comprehensive insight into chemical constituents and pharmacological effects on L. aggregata. The phytochemical investigation of different parts of L. aggregata led to the identification of up to 349 components belonging to sesquiterpenoids, alkaloids, flavonoids, essential oils, and other compounds. Among them, sesquiterpenoids, flavonoids, and alkaloids are assessed as representative active ingredients of L. aggregata. A wide variety of pharmacological effects of L. aggregata, such as anti-hyperlipidemic, anti-tumor, anti-inflammatory, analgesic, and anti-oxidant, have been proved in vitro and in vivo. In summary, this review aims to provide a scientific basis and reference for further research and utilization of L. aggregata and lay the foundation for developing functional foods with potential active ingredients for the prevention and management of related diseases.

11.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(5): 1387-1393, 2021 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-34627415

RESUMO

OBJECTIVE: To investigate the inhibitory effects of novel phosphodiesterase 4 inhibitor ZL-n-91 to the proliferation of leukemia cells L1210 and K562. METHODS: CCK-8 method was used to detect the effect of ZL-n-91 to the proliferation of L1210 and K562 cells, and the proliferation rate, IC50 were calculated. The effects of ZL-n-91 to the cycle of L1210 and K562 cells was detected by PE single staining, and the effects of ZL-n-91 to the apoptosis of L1210 and K562 cells was detected by PE/7AA-D double staining. Western blot was used to detect the effect of ZL-n-91 to the expression levels of apoptosis related proteins. Subcutaneous tumor transplantation model of acute lymphoblastic leukemia L1210 was established in the nude mice, and the inhibitory effect of oral administration of ZL-n-91 to the xenograft was observed. RESULTS: ZL-n-91 showed a significant inhibitory effect to the proliferation of leukemia cells L1210 and K562 in a dose-dependent manner (P<0.001). After treated by ZL-n-91, the leukemia cells L1210 and K562 in the S-phase in cell cycle decreased significantly compared with those in control group (P<0.01). The apoptosis of leukemia cells L1210 and K562 could be induced by ZL-n-91 (P<0.001), and the expression level of apoptosis related protein BAX significantly increased. In the animal experiment, the result showed that ZL-n-91 could significantly inhibit the growth of subcutaneously transplantation tumor (P<0.05). CONCLUSION: The novel phosphodiesterase 4 inhibitor ZL-n-91 can effectively inhibit the proliferation of leukemia cells L1210 and K562, which has the potential of anti-leukemia drug development.


Assuntos
Leucemia , Inibidores da Fosfodiesterase 4 , Animais , Proliferação de Células , Humanos , Células K562 , Camundongos , Camundongos Nus , Inibidores da Fosfodiesterase 4/farmacologia
12.
Adv Sci (Weinh) ; 8(19): e2101467, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34363341

RESUMO

Recent investigations reveal that lactate is not a waste product but a major energy source for cells, especially in the mitochondria, which can support cellular survival under glucose shortage. Accordingly, the new understanding of lactate prompts to target it together with glucose to pursue a more efficient cancer starvation therapy. Herein, zeolitic imidazolate framework-8 (ZIF-8) nanoplatforms are used to co-deliver α-cyano-4-hydroxycinnamate (CHC) and glucose oxidase (GOx) and fulfill the task of simultaneous depriving of lactate and glucose, resulting in a new nanomedicine CHC/GOx@ZIF-8. The synthesis conditions are carefully optimized in order to yield monodisperse and uniform nanomedicines, which will ensure reliable and steady therapeutic properties. Compared with the strategies aiming at a single carbon source, improved starvation therapy efficacy is observed. Besides, more than boosting the energy shortage, CHC/GOx@ZIF-8 can block the lactate-fueled respiration and relieve solid tumor hypoxia, which will enhance GOx catalysis activity, depleting extra glucose, and producing more cytotoxic H2 O2 . By the synergistically enhanced anti-tumor effect, both in vitro and in vivo cancer-killing efficacies of CHC/GOx@ZIF-8 show twice enhancements than the GOx mediated therapy. The results demonstrate that the dual-depriving of lactate and glucose is a more advanced strategy for strengthening cancer starvation therapy.


Assuntos
Ácidos Cumáricos/metabolismo , Glucose Oxidase/metabolismo , Glucose/metabolismo , Imidazóis/metabolismo , Ácido Láctico/metabolismo , Estruturas Metalorgânicas/metabolismo , Neoplasias/metabolismo , Neoplasias/terapia , Animais , Sobrevivência Celular , Camundongos , Nanomedicina/métodos , Nanopartículas/metabolismo
13.
Adv Mater ; 32(45): e2003471, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33029855

RESUMO

As a common feature in a majority of malignant tumors, hypoxia has become the Achilles' heel of photodynamic therapy (PDT). The development of type-I photosensitizers that show hypoxia-tolerant PDT efficiency provides a straightforward way to address this issue. However, type-I PDT materials have rarely been discovered. Herein, a π-conjugated molecule with A-D-A configuration, COi6-4Cl, is reported. The H2 O-dispersible nanoparticle of COi6-4Cl can be activated by an 880 nm laser, and displays hypoxia-tolerant type I/II combined PDT capability, and more notably, a high NIR-II fluorescence with a quantum yield over 5%. Moreover, COi6-4Cl shows a negligible photothermal conversion effect. The non-radiative decay of COi6-4Cl is suppressed in the dispersed and aggregated state due to the restricted molecular vibrations and distinct intermolecular steric hindrance induced by its four bulky side chains. These features make COi6-4Cl a distinguished single-NIR-wavelength-activated phototheranostic material, which performs well in NIR-II fluorescence-guided PDT treatment and shows an enhanced in vivo anti-tumor efficiency over the clinically approved Chlorin e6, by the equal stresses on hypoxia-tolerant anti-tumor therapy and deep-penetration imaging. Therefore, the great potential of COi6-4Cl in precise PDT cancer therapy against hypoxia challenges is demonstrated.


Assuntos
Raios Infravermelhos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Nanomedicina Teranóstica/métodos , Hipóxia Tumoral/efeitos dos fármacos , Hipóxia Tumoral/efeitos da radiação , Linhagem Celular Tumoral , Clorofilídeos , Humanos , Nanopartículas/química , Porfirinas/química , Porfirinas/farmacologia
14.
Macromol Biosci ; 20(9): e2000116, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32603032

RESUMO

Long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) for relieving inflammatory reactions can lead to severe side effects. It is of great importance to configure new dosing strategies for alleviating the side effects of NSAIDs. In this work, an enzyme-responsive anti-inflammatory prodrug capable of generating indomethacin upon the trigger of inflammation is developed. A monomer is first prepared after the esterification of carboxyl groups of indomethacin by hydroxyl groups of N-(2-hydroxyethyl) acrylamide. Then, a polymer prodrug, with indomethacin linked through ester bonds on the side chain, is synthesized by free radical polymerization of the monomer. The therapeutic drug component can be triggered to release from the prodrug under the stimulation of cholesterol esterase, mimicking the inflammation environment. On the contrary, there is only a small amount of drug released in the absence of the enzyme. Therefore, the drug can be triggered to release under the stimulation of an environment mimicking inflammation. Furthermore, the in vitro studies at the cellular level indicate that the enzyme-responsive prodrug can efficiently relieve inflammatory responses induced by lipopolysaccharide in RAW264.7 macrophage cells while indicating no cytotoxicity.


Assuntos
Liberação Controlada de Fármacos , Inflamação/tratamento farmacológico , Pró-Fármacos/uso terapêutico , Esterol Esterase/metabolismo , Animais , Morte Celular/efeitos dos fármacos , Indometacina/farmacologia , Indometacina/uso terapêutico , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico/metabolismo , Pró-Fármacos/síntese química , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Espectroscopia de Prótons por Ressonância Magnética , Células RAW 264.7 , Padrões de Referência
15.
Biomed Pharmacother ; 129: 110425, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32570123

RESUMO

Acute leukemia is a common hematological malignancy. Despite recent promising progress, the prognosis of acute leukemia patients remains to be improved. New therapies are therefore still needed. Salmonella typhimurium has been shown to be highly effective as an anti-tumor agent in many solid cancer models, but it has not been applied in acute leukemia. Here, we report an attenuated Salmonella typhimurium strain, VNP20009, can induce apoptosis in multiple types of leukemia cells both in vivo and in vitro. Furthermore, VNP20009 significantly inhibited the proliferation of MLL-AF9-induced acute myeloid leukemia cells and prolonged the survival of the AML-carrying mice. VNP20009 restored the counts of white blood cell (WBC) and its five subsets in peripheral blood (PB) to near-physiological values, and elevated the levels of certain cytokines, such as tumor necrosis factor-α (TNF-α), leukemia inhibitory factor (LIF), interferon-γ (IFN-γ), chemokine C-X-C motif ligand-10 (CXCL-10) and C-C motif ligand-2 (CCL-2). Moreover, the ratio of immune cells, including natural killer cells (NKs), CD4+ Th1-type cells and CD8+ IFN-γ-producing effector T cells were highly upregulated in the AML mice treated with VNP20009. The results of the present study potentially provide an alternative therapeutic strategy for hematologic malignancies through boosting the innate and adaptive anti-tumor immunity.


Assuntos
Antineoplásicos/farmacologia , Vacinas Bacterianas/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Imunidade Adaptativa/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/sangue , Células HL-60 , Humanos , Imunidade Inata/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Leucemia-Linfoma Linfoblástico de Células T Precursoras/sangue , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , Células Th1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
16.
ACS Appl Mater Interfaces ; 8(33): 21465-71, 2016 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-27483010

RESUMO

Singlet oxygen ((1)O2), as a reactive oxygen species, has garnered serious attention in physical, chemical, and biological studies. In this paper, we designed and synthesized a new type of singlet-oxygen generation system by exchanging cationic ruthenium complexes (RCs) into anionic bio-MOF-1. The resulting bio-MOF-1&RCs can be used as effective photocatalysts for generation of singlet oxygen under both single-photon and two-photon excitation. Especially, the excellent two-photon absorption (TPA) behavior of bio-MOF-1&RCs aroused our interest greatly because their two-photon absorption band lies in the optical window of biological tissue. Here, we measured the ability of bio-MOF-1&RCs to generate (1)O2 by irradiation under both 490 and 800 nm wavelength light in DMF. 1,3-Diphenylisobenzofuran (DPBF) and 2',7'-dichlorofluorescein (DCFH) were used as typical (1)O2 traps to detect and evaluate the efficiency of generation of (1)O2 under single-photon and two-photon excitation, respectively. Results indicated that bio-MOF-1&[Ru(phen)3](2+) was able to effectively generate (1)O2 under both conditions. Our work creates a novel synergistic TPA system with the excellent photophysical properties of RCs and the unique microporous structure benefit of MOFs, which may open a new avenue for creation of a cancer treatment system with both photodynamic therapy and chemotherapy.

17.
Mol Clin Oncol ; 3(3): 663-671, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26137284

RESUMO

The standard treatment for borderline and malignant phyllodes tumors is wide local excision (margins ≥1 cm), in the context of either breast-conserving surgery (BCS) or total mastectomy (TM). Due to the high risk of local recurrence (LR) following surgical intervention alone, the addition of adjuvant radiotherapy (RT) has been previously investigated; however, the conclusions have been inconsistent. This systematic review and meta-analysis was designed to assess the efficacy of adjuvant RT for borderline and malignant phyllodes tumors. Pubmed and Web of Science were systematically searched to identify relevant studies assessing the effect of adjuvant RT on borderline and malignant phyllodes tumors from the inception of this technique through May, 2014. A total of 8 studies were identified among 332 citations. In this meta-analysis, patients who received adjuvant RT had a lower relative risk of LR [hazard ratio (HR) = 0.43, 95% confidence interval (CI): 0.23-0.64]. The absolute risk difference was 10.1% (95% CI: 4.9-17.6), corresponding to a number needed to treat of 10. Our pooled meta-analysis clearly demonstrated a decreased risk of LR in patients with borderline and malignant phyllodes tumors who received RT following BCS (HR=0.31, 95% CI: -0.10-0.72). However, the combined HR for LR in the TM group did not demonstrate that adjuvant RT was superior to no RT (HR=0.68, 95% CI: -0.28-1.64). No significant differences were observed in overall survival (OS) or disease-free survival (DFS) between the two groups. Our analysis suggested that adjuvant RT for borderline and malignant phyllodes tumors decreased the LR rate in patients undergoing BCS. However, adjuvant RT was not found to exert an effect on OS or DFS.

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