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1.
World J Clin Cases ; 12(13): 2254-2262, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38808345

RESUMO

BACKGROUND: Gastric bronchogenic cysts (BCs) are extremely rare cystic masses caused by abnormal development of the respiratory system during the embryonic period. Gastric bronchial cysts are rare lesions that were first reported in 1956; as of 2023, only 33 cases are available in the PubMed online database. BCs usually have no clinical symptoms in the early stage, and imaging findings also lack specificity. Therefore, they are difficult to diagnose before histopathological examination. CASE SUMMARY: A 34-year-old woman with respiratory distress presented at our hospital. Endoscopic ultrasound revealed an anechoic mass between the spleen, left kidney and gastric fundus, with hyperechogenic and soft elastography textures and with a size of approximately 6.5 cm × 4.0 cm. Furthermore, a computed tomography scan demonstrated high density between the posterior stomach and the spleen and the left kidney, with uniform internal density and a small amount of calcification. The maximum cross section was approximately 10.1 cm × 6.1 cm, and the possibility of a cyst was high. Because the imaging findings did not suggest a malignancy and because the patient required complete resection, she underwent laparotomy surgery. Intraoperatively, this cystic lesion was found to be located in the posterior wall of the large curvature of the fundus and was approximately 8 cm × 6 cm in size. Finally, the pathologists verified that the cyst in the fundus was a gastric BC. The patient recovered well, her symptoms of chest tightness disappeared, and the abdominal drain was removed on postoperative day 6, after which she was discharged on day 7 for 6 months of follow-up. She had no tumor recurrence or postoperative complications during the follow-up. CONCLUSION: This is a valuable report as it describes an extremely rare case of gastric BC. Moreover, this was a very young patient with a large BC in the stomach.

2.
Sci China Life Sci ; 67(7): 1427-1440, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38523237

RESUMO

Fucosyltransferase 8 (Fut8) and core fucosylation play critical roles in regulating various biological processes, including immune response, signal transduction, proteasomal degradation, and energy metabolism. However, the function and underlying mechanism of Fut8 and core fucosylation in regulating adult neurogenesis remains unknown. We have shown that Fut8 and core fucosylation display dynamic features during the differentiation of adult neural stem/progenitor cells (aNSPCs) and postnatal brain development. Fut8 depletion reduces the proliferation of aNSPCs and inhibits neuronal differentiation of aNSPCs in vitro and in vivo, respectively. Additionally, Fut8 deficiency impairs learning and memory in mice. Mechanistically, Fut8 directly interacts with integrin α6 (Itga6), an upstream regulator of the PI3k-Akt signaling pathway, and catalyzes core fucosylation of Itga6. Deletion of Fut8 enhances the ubiquitination of Itga6 by promoting the binding of ubiquitin ligase Trim21 to Itga6. Low levels of Itga6 inhibit the activity of the PI3K/Akt signaling pathway. Moreover, the Akt agonist SC79 can rescue neurogenic and behavioral deficits caused by Fut8 deficiency. In summary, our study uncovers an essential function of Fut8 and core fucosylation in regulating adult neurogenesis and sheds light on the underlying mechanisms.


Assuntos
Cognição , Fucosiltransferases , Integrina alfa6 , Neurogênese , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Animais , Fucosiltransferases/metabolismo , Fucosiltransferases/genética , Neurogênese/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Integrina alfa6/metabolismo , Integrina alfa6/genética , Cognição/fisiologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Diferenciação Celular , Proliferação de Células , Camundongos Endogâmicos C57BL , Camundongos Knockout
3.
Invest Ophthalmol Vis Sci ; 64(15): 15, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38095908

RESUMO

Purpose: The underlying mechanism of congenital cataracts caused by deficiency or mutation of junctional adhesion molecule C (JAM-C) gene remains unclear. Our study aims to elucidate the abnormal developmental process in Jamc-/- lenses and reveal the genes related to lens development that JAM-C may regulate. Methods: Jamc knockout (Jamc-/-) mouse embryos and pups were generated for in vivo studies. Four key developmental stages from embryonic day (E) 12.5 to postnatal day (P) 0.5 were selected for the following experiments. Hematoxylin and eosin staining was used for histological analysis. The 5-bromo-2'-deoxyuridine (BrdU) incorporation assay and TUNEL staining were performed to label lens epithelial cell (LEC) proliferation and apoptosis, respectively. Immunofluorescence and Western blot were used to analyze the markers of lens epithelium, cell cycle exit, and lens fiber differentiation. Results: JAM-C was expressed throughout the process of lens development. Deletion of Jamc resulted in decreased lens size and disorganized lens fibers, which arose from E16.5 and aggravated gradually. The LECs of Jamc-/- lenses showed decreased quantity and proliferation, accompanied with reduction of key transcription factor, FOXE3. The fibers in Jamc-/- lenses were disorganized. Moreover, Jamc-deficient lens fibers showed significantly altered distribution patterns of Cx46 and Cx50. The marker of fiber homeostasis, γ-crystallin, was also decreased in the inner cortex and core fibers of Jamc-/- lenses. Conclusions: Deletion of JAM-C exhibits malfunction of LEC proliferation and fiber maturation during murine lens development, which may be related to the downregulation of FOXE3 expression and abnormal localization patterns of Cx46 and Cx50.


Assuntos
Molécula C de Adesão Juncional , Cristalino , Animais , Camundongos , Diferenciação Celular/fisiologia , Proliferação de Células , Células Epiteliais/metabolismo , Epitélio , Molécula C de Adesão Juncional/metabolismo , Cristalino/metabolismo , Camundongos Knockout
4.
Signal Transduct Target Ther ; 8(1): 305, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-37591843

RESUMO

Although VEGF-B was discovered as a VEGF-A homolog a long time ago, the angiogenic effect of VEGF-B remains poorly understood with limited and diverse findings from different groups. Notwithstanding, drugs that inhibit VEGF-B together with other VEGF family members are being used to treat patients with various neovascular diseases. It is therefore critical to have a better understanding of the angiogenic effect of VEGF-B and the underlying mechanisms. Using comprehensive in vitro and in vivo methods and models, we reveal here for the first time an unexpected and surprising function of VEGF-B as an endogenous inhibitor of angiogenesis by inhibiting the FGF2/FGFR1 pathway when the latter is abundantly expressed. Mechanistically, we unveil that VEGF-B binds to FGFR1, induces FGFR1/VEGFR1 complex formation, and suppresses FGF2-induced Erk activation, and inhibits FGF2-driven angiogenesis and tumor growth. Our work uncovers a previously unrecognized novel function of VEGF-B in tethering the FGF2/FGFR1 pathway. Given the anti-angiogenic nature of VEGF-B under conditions of high FGF2/FGFR1 levels, caution is warranted when modulating VEGF-B activity to treat neovascular diseases.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Fator B de Crescimento do Endotélio Vascular , Humanos , Fator 2 de Crescimento de Fibroblastos/genética , Imunoterapia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética
5.
BMC Surg ; 23(1): 223, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37559035

RESUMO

BACKGROUND: At present, there is no convincing evidence-based medical basis for the efficacy of single-port laparoscopic gastrectomy. To make a high-quality comparison of the short- and long-term outcomes of single-port laparoscopic gastrectomy versus multiport laparoscopic gastrectomy, we performed this meta-analysis, which only included propensity score-matched studies and randomized controlled trials comparing single-port laparoscopic gastrectomy with multiport laparoscopic gastrectomy for patients with gastric cancer. METHODS: Data were retrieved from the electronic databases PubMed, EMBASE, Medline, Cochrane Library, CNKI, Wanfang and VIP up to January 2023, and the data included the outcomes of treatment after single-port laparoscopic gastrectomy and multiport laparoscopic gastrectomy. The primary outcomes were early complications, survival rate after surgery at 1 year, and survival rate after surgery at 5 years. The secondary outcomes were number of pain medications, mean operation time, estimated blood loss, hospital mortality, time to first soft fluid diet, time to first flatus, hospital stay after surgery, and retrieved number of lymph nodes. The Jadad score and Newcastle‒Ottawa scale were used to assess the quality of the included studies. RESULTS: After screening, 9 studies were finally included, including 988 patients. The meta-analysis results showed that estimated blood loss (MD=-29.35, 95% CI: -42.95-15.75, P < 0.0001), hospital stay (MD=-0.99, 95% CI:-1.82~-0.17, P = 0.02), and number of pain medications(MD=-0.65, 95% CI:-1.07~-0.23, P = 0.002) in the single-port laparoscopic gastrectomy group were better than those in the multiport laparoscopic gastrectomy group. There is no significant difference between the single-port laparoscopic gastrectomy group and the multiport laparoscopic gastrectomy group in mean operation time(MD = 5.23,95% CI:-16.58~27.04,P = 0.64), time to first soft fluid diet(MD=-0.06,95% CI: -0.30~0.18,P = 0.63), time to first flatus(MD=-0.18,95% CI:-0.43~0.07,P = 0.16), early complication(OR = 0.73,95% CI:0.50~1.09,P = 0.12), hospital mortality(OR = 1.00,95% CI:0.09~11.16,P = 1.00), retrieved number of lymph nodes(MD=-1.15, 95% CI:-2.71~0.40, P = 0.15), survival rate after surgery 1 year(OR = 2.14,95% CI:0.50~9.07,P = 0.30), and survival rate after surgery 5 year(93.7 vs. 87.6%; p = 0.689). CONCLUSION: This meta-analysis showed that single-port laparoscopic gastrectomy is both safe and feasible for laparoscopic radical gastrectomy for gastric cancer, with similar operation times and better short-term outcomes than multiport laparoscopic gastrectomy in terms of hospital stay, postoperative pain, and estimated blood loss. There was no significant difference in long-term outcomes between single-port laparoscopic gastrectomy and multiport laparoscopic gastrectomy.


Assuntos
Laparoscopia , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Flatulência/cirurgia , Pontuação de Propensão , Ensaios Clínicos Controlados Aleatórios como Assunto , Laparoscopia/métodos , Dor Pós-Operatória/cirurgia , Gastrectomia/métodos , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia
6.
Int Urol Nephrol ; 55(10): 2373-2379, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37393384

RESUMO

PURPOSE: The aims of this study were to analyze the clinical outcomes of treating duplex system ureteroceles with early endoscopic puncture decompression and to identify the risk factors related to outcomes to help guide future work. MATERIALS AND METHODS: We retrospectively reviewed the clinical records of patients with ureteroceles with duplex kidney that were treated with early endoscopic puncture decompression. Charts were reviewed for demographics, preoperative imaging, surgical indications, and follow-up data. Recurrent febrile urinary tract infections (fUTIs), de novo vesicoureteral reflux (VUR), persistent high-grade VUR, unrelieved hydroureteronephrosis, and the need for further intervention were considered unfavorable outcomes. Gender, age at surgery, BMI, antenatal diagnosis, fUTIs, bladder outlet obstruction (BOO), type of ureterocele, ipsilateral VUR diagnosed before surgery, simultaneously upper-pole moiety (UM) and lower-pole moiety (LM) obstruction, the width of ureter affiliated to UM, and maximum diameter of ureterocele were all considered potential risk factors. A binary logistic regression model was used to identify the risk factors of unfavorable outcomes. RESULTS: A total of 36 patients with ureteroceles related to duplex kidney underwent endoscopic holmium laser puncture from 2015 to 2023 at our institution. After a median follow-up of 21.6 months, unfavorable outcomes developed in 17 patients (47.2%). Three patients underwent ipsilateral common-sheath ureter reimplantation and one patient underwent laparoscopic ipsilateral upper to lower ureteroureterostomy combined with recipient ureter reimplantation. Three patients underwent laparoscopic upper-pole nephrectomy. Fifteen patients suffered from recurrent UTIs were treated with oral antibiotics and eight of them were diagnosed de novo VUR according to voiding cystourethrography (VCUG). In univariate analysis, patients with simultaneously UM and LM obstruction (P = 0.003), fUTIs before surgery (P = 0.044), and ectopic ureterocele (P = 0.031) were more likely to have unfavorable outcomes. Binary logistic regression analysis showed that ectopic ureterocele (OR = 10.793, 95% CI 1.248-93.312, P = 0.031) and simultaneously UM and LM obstruction (OR = 8.304, 95% CI 1.311-52.589, P = 0.025) were identified as independent factors for unfavorable outcomes. CONCLUSIONS: Our study suggested that early endoscopic puncture decompression is not a preferred but an available treatment option to release BOO or to cure refractory UTIs. It was easier to fail if the ureterocele was ectopic or simultaneously UM and LM obstruction existed. Gender, age at surgery, BMI, antenatal diagnosis, fUTIs, bladder outlet obstruction (BOO), ipsilateral VUR diagnosed before surgery, the width of ureter affiliated to UM, and maximum diameter of ureterocele were not significantly related to the success rate of early endoscopic punctures.


Assuntos
Nefropatias , Laparoscopia , Ureterocele , Obstrução do Colo da Bexiga Urinária , Infecções Urinárias , Refluxo Vesicoureteral , Criança , Humanos , Feminino , Gravidez , Lactente , Ureterocele/complicações , Ureterocele/cirurgia , Ureterocele/diagnóstico , Estudos Retrospectivos , Obstrução do Colo da Bexiga Urinária/complicações , Nefropatias/etiologia , Rim , Refluxo Vesicoureteral/complicações , Refluxo Vesicoureteral/cirurgia , Infecções Urinárias/etiologia , Fatores de Risco , Punções/métodos , Laparoscopia/efeitos adversos , Descompressão/efeitos adversos , Resultado do Tratamento
7.
Cells ; 11(8)2022 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-35455963

RESUMO

Nicotinamide adenine dinucleotide hydrate (NAD+) acts as the essential component of the tricarboxylic citric acid (TCA) cycle and has important functions in diverse biological processes. However, the roles of NAD+ in regulating adult neural stem/progenitor cells (aNSPCs) remain largely unknown. Here, we show that NAD+ exposure leads to the reduced proliferation and neuronal differentiation of aNSPCs and induces the apoptosis of aNSPCs. In addition, NAD+ exposure inhibits the morphological development of neurons. Mechanistically, RNA sequencing revealed that the transcriptome of aNSPCs is altered by NAD+ exposure. NAD+ exposure significantly decreases the expression of multiple genes related to ATP metabolism and the PI3k-Akt signaling pathway. Collectively, our findings provide some insights into the roles and mechanisms in which NAD+ regulates aNSPCs and neuronal development.


Assuntos
NAD , Células-Tronco Neurais , Proliferação de Células , NAD/metabolismo , Células-Tronco Neurais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
8.
Curr Eye Res ; 47(4): 555-564, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34872443

RESUMO

PURPOSE: Autophagy plays a crucial role in intracellular quality control of crystalline lens and AMPK has regulatory effect on autophagy. However, whether AMPK regulated autophagy is involved in diabetic cataract (DC) progression remains unknown. This study aims to investigate the AMPK-FOXO3 and AMPK-TFEB induced autophagy activity in DC patients. MATERIALS AND METHODS: First, anterior capsule specimens from DC and age-related cataract (ARC) patients were obtained to compare the expression difference of autophagy-related genes. The phosphorylation levels of AMPK, AKT, and mTOR and the expression of FOXO3 and TFEB were measured. Then, human lens epithelial cells (LECs, SRA 01/04) were cultured with 30 mM or 5.5 mM glucose, and AMPK activator (AICAR) and inhibitor (Compound C) were applied to further investigate the regulatory role of AMPK on autophagy. RESULTS: Compared with ARC patients, the expression of autophagy-related genes ATG5, FYCO1, ATG8, ATG12, Beclin1, and ULK1 in anterior capsules LECs of DC patients were significantly down-regulated. Meanwhile, AMPK and AMPK-dependent transcription factors, FOXO3 and TFEB were also inhibited. Similar results were found in high glucose (HG) treated SRA 01/04 model. Notably, this down-regulation of autophagy activity was rescued by AICAR in vitro, which was manifested by inhibition of AKT and mTOR phosphorylation and up-regulation of FOXO3, TFEB, Beclin1 and LC3B-II expression. CONCLUSIONS: Down-regulation of AMPK-FOXO3 and AMPK-TFEB induced autophagy activity was found in both LECs of anterior capsule from DC patients and SRA 01/04 cells under HG condition, which may be the underlying mechanism of DC formation. Thus, targeting AMPK-induced autophagy may be a potential therapeutic approach for diabetic cataract.


Assuntos
Catarata , Diabetes Mellitus , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/farmacologia , Proteína Beclina-1/metabolismo , Regulação para Baixo , Proteína Forkhead Box O3/genética , Proteína Forkhead Box O3/metabolismo , Glucose/farmacologia , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Serina-Treonina Quinases TOR/farmacologia
9.
J Exp Clin Cancer Res ; 40(1): 367, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34794490

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy has yielded impressive outcomes and transformed treatment algorithms for hematological malignancies. To date, five CAR T-cell products have been approved by the US Food and Drug Administration (FDA). Nevertheless, some significant toxicities pose great challenges to the development of CAR T-cell therapy, most notably cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Understanding the mechanisms underlying these toxicities and establishing prevention and treatment strategies are important. In this review, we summarize the mechanisms underlying CRS and ICANS and provide potential treatment and prevention strategies.


Assuntos
Síndrome da Liberação de Citocina/prevenção & controle , Síndrome da Liberação de Citocina/terapia , Imunoterapia Adotiva/métodos , Síndromes Neurotóxicas/prevenção & controle , Síndromes Neurotóxicas/terapia , Humanos
10.
Front Immunol ; 11: 569117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33643279

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy exhibits desirable and robust efficacy in patients with acute lymphoblastic leukemia (ALL). Stimulated by the revolutionized progress in the use of FDA-approved CD19 CAR T cells, novel agents with CAR designs and targets are being produced in pursuit of superior performance. However, on the path from bench to bedside, new challenges emerge. Accessibility is considered the initial barrier to the transformation of this patient-specific product into a commercially available product. To ensure infusion safety, profound comprehension of adverse events and proactive intervention are required. Additionally, resistance and relapse are the most critical and intractable issues in CAR T-cell therapy for ALL, thus precluding its further development. Understanding the limitations through up-to-date insights and characterizing multiple strategies will be critical to leverage CAR T-cell therapy flexibly for use in clinical situations. Herein, we provide an overview of the application of CAR T-cell therapy in ALL, emphasizing the main challenges and potential clinical strategies in an effort to promote a standardized set of treatment paradigms for ALL.


Assuntos
Imunoterapia Adotiva , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos Quiméricos/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/imunologia , Antígenos de Neoplasias/metabolismo , Tomada de Decisão Clínica , Ensaios Clínicos como Assunto , Terapia Combinada/métodos , Gerenciamento Clínico , Suscetibilidade a Doenças , Resistencia a Medicamentos Antineoplásicos , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Recidiva , Retratamento , Linfócitos T/metabolismo , Resultado do Tratamento
11.
Front Immunol ; 10: 2664, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798590

RESUMO

Chimeric antigen receptor (CAR) T-cell therapy is highly effective in the treatment of B-cell acute lymphoblastic leukemia (ALL) or B-cell lymphoma, providing alternative therapeutic options for patients who failed to respond to conventional treatment or relapse. Moreover, it can bridge other therapeutic strategies and greatly improve patient prognosis, with broad applicable prospects. Even so, 30-60% patients relapse after treatment, probably due to persistence of CAR T-cells and escape or downregulation of CD19 antigen, which is a great challenge for disease control. Therefore, understanding the mechanisms that underlie post-CAR relapse and establishing corresponding prevention and treatment strategies is important. Herein, we discuss post-CAR relapse from the aspects of CD19-positive and CD19-negative and provide some reasonable prevention and treatment strategies.


Assuntos
Antígenos CD19/imunologia , Imunoterapia Adotiva/métodos , Recidiva Local de Neoplasia/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Receptores de Antígenos Quiméricos/uso terapêutico , Humanos , Receptores de Antígenos Quiméricos/imunologia
12.
Adv Mater ; 29(14)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28234430

RESUMO

Current cancer nanomedicines can only mitigate adverse effects but fail to enhance therapeutic efficacies of anticancer drugs. Rational design of next-generation cancer nanomedicines should aim to enhance their therapeutic efficacies. Taking this into account, this review first analyzes the typical cancer-drug-delivery process of an intravenously administered nanomedicine and concludes that the delivery involves a five-step CAPIR cascade and that high efficiency at every step is critical to guarantee high overall therapeutic efficiency. Further analysis shows that the nanoproperties needed in each step for a nanomedicine to maximize its efficiency are different and even opposing in different steps, particularly what the authors call the PEG, surface-charge, size and stability dilemmas. To resolve those dilemmas in order to integrate all needed nanoproperties into one nanomedicine, stability, surface and size nanoproperty transitions (3S transitions for short) are proposed and the reported strategies to realize these transitions are comprehensively summarized. Examples of nanomedicines capable of the 3S transitions are discussed, as are future research directions to design high-performance cancer nanomedicines and their clinical translations.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Nanopartículas , Neoplasias/tratamento farmacológico , Animais , Descoberta de Drogas/métodos , Humanos , Nanomedicina/métodos , Nanopartículas/química , Neoplasias/metabolismo
13.
Biomater Sci ; 4(6): 958-69, 2016 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-27087640

RESUMO

An inherent dilemma in the use of nanomedicines for cancer drug delivery is their limited penetration into tumors due to their large size. We have demonstrated that dendrimer/lipid nanoassemblies can solve this problem by means of tumor-triggered disassembly and the release of small (several nanometers) dendrimers to facilitate tumor penetration. Herein, we report a general strategy for the fabrication of nanoassemblies from hydrophobic and hydrophilic dendrimers with phospholipids. Hydrophobic dendrimers could assemble with lipids via hydrophobic interactions, whereas hydrophilic dendrimers could only assemble with lipids in the presence of anionic surfactants via both electrostatic and hydrophobic interactions. The nanoassemblies of hydrophobic dendrimers/lipids were found to be capable of stripping off their lipid layers via fusion with the cell membrane and then intracellular or extracellular release of dendrimers, whereas the nanoassemblies of hydrophilic dendrimers/lipids were internalized via endocytosis and then released their dendrimers inside the cells. Therefore, these dendrimer/lipid nanoassemblies could be used for the delivery of different cancer drugs.


Assuntos
Dendrímeros/química , Sistemas de Liberação de Medicamentos , Bicamadas Lipídicas/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Linhagem Celular Tumoral/citologia , Linhagem Celular Tumoral/metabolismo , Linhagem Celular Tumoral/ultraestrutura , Dendrímeros/metabolismo , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Nanomedicina , Neoplasias Ovarianas , Poliaminas/química , Eletricidade Estática
14.
J Mater Chem B ; 3(38): 7594-7603, 2015 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262643

RESUMO

Tumor-targeting, redox-responsive and high drug-loaded nanoparticles were synthesized from poly(ethylene glycol)-b-poly(l-lysine) (PEG-PLL) for enhanced cancer therapy. A hydrophobic drug camptothecin (CPT) was anchored to the lysine residual amines in PEG-PLL via disulfide bonds. Folate acid as targeting group was further introduced to the PLL block via long PEG chains. The conjugate self-assembled into nanoparticles of around 100 nm with hydrophobic CPT moieties forming the core and folate acid targeting groups on the shell. The nanoparticles were expected to be stable in the blood circulation but once internalized via folate receptor-mediated endocytosis, disintegrate and release the drug by glutathione in the cytosol. The nanoparticles could be used as a nanocarrier to further encapsulate other drugs such as doxorubicin for combined chemotherapy. The CPT-conjugated nanoparticles had comparable cytotoxicity to free CPT at low doses but higher cytotoxicity than CPT at high doses.

15.
Adv Mater ; 26(45): 7615-21, 2014 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-25328159

RESUMO

A "cluster-bomb"-like lipid-dendrimer nanoassembly synergizes the functions of its components and thereby efficiently accomplishes the drug delivery cascade for high efficacy in treating cancer. The nanoassembly successfully circulates in the blood and accumulates in the tumor. Once in the tumor, it releases small dendrimers that act like "bomblets", enabling tumor penetration, cell internalization, and drug release.


Assuntos
Antineoplásicos/administração & dosagem , Dendrímeros , Sistemas de Liberação de Medicamentos/métodos , Nanoestruturas/química , Animais , Linhagem Celular Tumoral , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Colesterol/química , Doxorrubicina/administração & dosagem , Feminino , Humanos , Camundongos , Camundongos Nus , Micelas , Nanomedicina/métodos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Fosfatidiletanolaminas/química , Polietilenoglicóis/química
16.
Angew Chem Int Ed Engl ; 53(41): 10949-55, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25155439

RESUMO

The structural preciseness of dendrimers makes them perfect drug delivery carriers, particularly in the form of dendrimer-drug conjugates. Current dendrimer-drug conjugates are synthesized by anchoring drug and functional moieties onto the dendrimer peripheral surface. However, functional groups exhibiting the same reactivity make it impossible to precisely control the number and the position of the functional groups and drug molecules anchored to the dendrimer surface. This structural heterogeneity causes variable pharmacokinetics, preventing such conjugates to be translational. Furthermore, the highly hydrophobic drug molecules anchored on the dendrimer periphery can interact with blood components and alter the pharmacokinetic behavior. To address these problems, we herein report molecularly precise dendrimer-drug conjugates with drug moieties buried inside the dendrimers. Surprisingly, the drug release rates of these conjugates were tailorable by the dendrimer generation, surface chemistry, and acidity.


Assuntos
Antineoplásicos Fitogênicos/química , Dendrímeros/química , Portadores de Fármacos/química , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/toxicidade , Camptotecina/química , Camptotecina/uso terapêutico , Camptotecina/toxicidade , Carbocianinas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citometria de Fluxo , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Polilisina/química , Transplante Heterólogo
17.
J Am Chem Soc ; 135(2): 933-40, 2013 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-23253016

RESUMO

Cell-penetrating peptides (CPPs) such as transactivator of transcription (TAT) peptide have long been explored for promoting in vitro cell penetration and nuclear targeting of various cargos, but their positive charges cause strong nonspecific interactions, making them inapplicable for many in vivo applications. In this work, we used TAT to demonstrate a molecular modification approach for inhibiting nonspecific interactions of CPPs in the bloodstream while reactivating their functions in the targeted tissues or cells. The TAT lysine residues' amines were amidized to succinyl amides ((a)TAT), completely inhibiting TAT's nonspecific interactions in the blood compartment; once in the acidic tumor interstitium or internalized into cell endo/lysosomes, the succinyl amides in the (a)TAT were quickly hydrolyzed, fully restoring TAT's functions. Thus, (a)TAT-functionalized poly(ethylene glycol)-block-poly(ε-caprolactone) micelles achieved long circulation in the blood compartment and efficiently accumulated and delivered doxorubicin to tumor tissues, giving rise to high antitumor activity and low cardiotoxicity. This amidization strategy effectively and easily enables in vivo applications of CPPs.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Peptídeos Penetradores de Células/uso terapêutico , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Micelas , Linhagem Celular Tumoral , Feminino , Humanos , Modelos Biológicos
18.
J Control Release ; 164(2): 156-69, 2012 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-22664472

RESUMO

Cancer drug delivery achieving high therapeutic efficacy and low side effects requires a nanocarrier to tightly retain the drug, efficiently reach the tumor, then quickly enter the tumor cells and release the drug. Furthermore, the nanocarrier intended for clinical applications should use materials safe as pharmaceutical excipients and its formulation (nanomedicine) should have good manufacture processes with scale-up ability. Thus, the challenge is to design safe, approvable, and easily scaled-up nanocarriers that simultaneously meet the two pairs of requirements of 'drug retention in circulation versus intracellular release' and 'stealthy in circulation versus sticky (cell-binding) in tumor' at the right places in order to deliver a cytosolic drug dose lethal to cancer cells with minimized side effects. Herein, we briefly review these elements aimed at promoting developments of translational nanocarriers.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Animais , Portadores de Fármacos/administração & dosagem , Desenho de Fármacos , Humanos , Nanomedicina , Nanopartículas/administração & dosagem , Pesquisa Translacional Biomédica
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