Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Angew Chem Int Ed Engl ; 62(4): e202212400, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36346623

RESUMO

The great significance of boosting the design of percolating nanopore structures in block copolymers (BCPs) for various cases has been widely demonstrated in the past several decades. However, it still remains challenging to prepare the desired porous structures in a rapid, facile, and universal manner. Here we have developed an unconventional and benchtop strategy to rapidly generate the nanoporous polystyrene-based BCPs with arbitrary structural characteristics regardless of the BCP bulk morphology. This universal pore-forming strategy enables the sustainable CO2 -based BCPs to form advanced membranes after 1 s soaking for efficiently rejecting 94.2 % brilliant blue R (826 g mol-1 ). Meanwhile, the water permeance retains around 1020 L (m2 h bar)-1 , which is 1-3 orders of magnitude higher than that of other membranes. This strategy may offer an excellent opportunity to introduce percolating pore structures in those newly developed BCPs with which the previously reported pore-forming methods may not deal.

2.
Chem Soc Rev ; 50(11): 6333-6348, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33890584

RESUMO

Removing hazardous particulate and macromolecular contaminants as well as viruses with sizes from a few nm up to the 100 nm-range from water and air is crucial for ensuring sufficient sanitation and hygiene for a growing world population. To this end, high-performance separation membranes are needed that combine high permeance, high selectivity and sufficient mechanical stability under operating conditions. However, design features of separation membranes enhancing permeance reduce selectivity and vice versa. Membrane configurations combining high permeance and high selectivity suffer in turn from a lack of mechanical robustness. These problems may be tackled by using block copolymers (BCPs) as a material platform for the design of separation membranes. BCPs are macromolecules that consist of two or more chemically distinct block segments, which undergo microphase separation yielding a wealth of ordered nanoscopic domain structures. Various methods allow the transformation of these nanoscopic domain structures into customized nanopore systems with pore sizes in the sub-100 nm range and with narrow pore size distributions. This tutorial review summarizes design strategies for nanoporous state-of-the-art BCP separation membranes, their preparation, their device integration and their use for water purification.

3.
J Pharmacol Exp Ther ; 374(1): 184-199, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32273304

RESUMO

The objective of this work was to develop a systems pharmacokinetics-pharmacodynamics (PK-PD) model that can characterize in vivo bystander effect of antibody-drug conjugate (ADC) in a heterogeneous tumor. To accomplish this goal, a coculture xenograft tumor with 50% GFP-MCF7 (HER2-low) and 50% N87 (HER2-high) cells was developed. The relative composition of a heterogeneous tumor for each cell type was experimentally determined by immunohistochemistry analysis. Trastuzumab-vc-MMAE (T-vc-MMAE) was used as a tool ADC. Plasma and tumor PK of T-vc-MMAE was analyzed in N87, GFP-MCF7, and coculture tumor-bearing mice. In addition, tumor growth inhibition (TGI) studies were conducted in all three xenografts at different T-vc-MMAE dose levels. To characterize the PK of ADC in coculture tumors, our previously published tumor distribution model was evolved to account for different cell populations. The evolved tumor PK model was able to a priori predict the PK of all ADC analytes in the coculture tumors reasonably well. The tumor PK model was subsequently integrated with a PD model that used intracellular tubulin occupancy to drive ADC efficacy in each cell type. The final systems PK-PD model was able to simultaneously characterize all the TGI data reasonably well, with a common set of parameters for MMAE-induced cytotoxicity. The model was later used to simulate the effect of different dosing regimens and tumor compositions on the bystander effect of ADC. The model simulations suggested that dose-fractionation regimen may further improve overall efficacy and bystander effect of ADCs by prolonging the tubulin occupancy in each cell type. SIGNIFICANCE STATEMENT: A PK-PD analysis is presented to understand bystander effect of Trastuzumab-vc-MMAE ADC in antigen (Ag)-low, Ag-high, and coculture (i.e., Ag-high + Ag-low) xenograft mice. This study also describes a novel single cell-level systems PK-PD model to characterize in vivo bystander effect of ADCs. The proposed model can serve as a platform to mathematically characterize multiple cell populations and their interactions in tumor tissues. Our analysis also suggests that fractionated dosing regimen may help improve the bystander effect of ADCs.


Assuntos
Efeito Espectador/efeitos dos fármacos , Imunoconjugados/farmacologia , Imunoconjugados/farmacocinética , Modelos Biológicos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , Humanos , Distribuição Tecidual
4.
Drug Metab Dispos ; 47(10): 1136-1145, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31387870

RESUMO

In this study, we evaluated the effect of size on tumor disposition of protein therapeutics, including the plasma and tumor pharmacokinetics (PK) of trastuzumab (∼150 kDa), FcRn-nonbinding trastuzumab (∼150 kDa), F(ab)2 fragment of trastuzumab (∼100 kDa), Fab fragment of trastuzumab (∼50 kDa), and trastuzumab scFv (∼27 kDa) in both antigen (i.e., HER2)-overexpressing (N87) and antigen-nonexpressing (MDA-MB-468) tumor-bearing mice. The observed data were used to develop the maximum tumor uptake versus molecular weight and tumor-to-plasma area under the curve (AUC) ratio versus molecular weight relationships. Comparison of the PK of different sizes of FcRn nonbinding molecules in target-expressing tumor showed that ∼100 kDa is an optimal size to achieve maximum tumor uptake and ∼50 kDa is an optimal size to achieve maximum tumor-to-plasma exposure ratio of protein therapeutics. The PK data were also used to validate a systems PK model for tumor disposition of different-sized protein therapeutics. The PK model was able to predict a priori the PK of all five molecules in both tumor types reasonably well (within 2- to 3-fold). In addition, the model captured the bell-shaped relationships observed between maximum tumor uptake and molecular weight and between tumor-to-plasma AUC ratio and molecular weight. Our results provide an unprecedented insight into the effect of size and target engagement on the tumor PK of protein therapeutics. Our results also provide further validation of the tumor disposition model, which can be used to support discovery, development, and preclinical-to-clinical translation of different sizes of protein therapeutics. SIGNIFICANCE STATEMENT: This article highlights the importance of molecular size and target engagement on the tumor disposition of protein therapeutics. Our results suggest that ∼100 kDa is an optimal size to achieve maximum tumor uptake and ∼50 kDa is an optimal size to achieve maximum tumor-to-plasma exposure ratio for non-FcRn-binding targeted protein therapeutics. We also demonstrate that a systems pharmacokinetics model developed to characterize tumor disposition of protein therapeutics can predict a priori the disposition of different-sized protein therapeutics in target-expressing and target-nonexpressing solid tumors.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias/tratamento farmacológico , Receptor ErbB-2/antagonistas & inibidores , Receptores Fc/metabolismo , Anticorpos de Cadeia Única/farmacologia , Trastuzumab/farmacocinética , Animais , Área Sob a Curva , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Modelos Biológicos , Peso Molecular , Neoplasias/sangue , Neoplasias/patologia , Receptor ErbB-2/metabolismo , Anticorpos de Cadeia Única/administração & dosagem , Anticorpos de Cadeia Única/química , Distribuição Tecidual , Trastuzumab/administração & dosagem , Trastuzumab/química , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Future Oncol ; 15(35): 4019-4030, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31612729

RESUMO

Aim: Tumor associated macrophages are the most abundant cancer immune cells. However, little was known about the identity of CD68+PD1+ macrophages as well as the contributions in the prognosis of esophageal squamous cell carcinoma (ESCC). Methods & methods: Immunofluorescence, flowcytometry and RT-PCR were used to analysis PD1+ macrophages in ESCC. Results: CD68+PD1+ macrophages which can express higher M2 markers in cancer tissues, increased about 4.2-times compared with para-cancer tissues. Additionally, PD1high macrophages were significantly correlated with more malignant phenotypes and poor prognosis. PD1 treatment can enhance phagocytosis of cultured macrophages and redirect this macrophage to M1-like phenotype. Conclusion: Thus, our findings overall indicate that CD68+PD1+ macrophages are tumor associated macrophagess in ESCC, which can forecast the prognosis of ESCC.


Assuntos
Biomarcadores Tumorais , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago/mortalidade , Macrófagos/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Adulto , Idoso , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Linhagem Celular Tumoral , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Estimativa de Kaplan-Meier , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Fagocitose , Prognóstico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Microambiente Tumoral
6.
Cell Physiol Biochem ; 51(5): 2212-2223, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30537730

RESUMO

BACKGROUND/AIMS: TNF-related apoptosis-inducing ligand (TRAIL) is a novel and low-toxic anti-tumor drug used for various cancers. However, cancer cells usually develop mechanisms to acquire the resistance against TRAIL. Among these changes, dysregulation of microRNAs (miRNAs) usually occurs in cancer cells and is responsible for induction of drug resistance. METHODS: Expression of miR-494 in gastric cancer tissues and cell lines was detected by quantitative reverse transcriptase real time PCR (qRT-PCR) analysis. Effect of miR-494 on regulating the TRAIL sensitivity to gastric cancer cell lines was evaluated by MTT assays. Bioinformatics and luciferase reporter assays were used to confirm the regulation of miR-494 on survivin. Mitochondrial apoptosis pathway in gastric cancer cells was tested by western blot and flow cytometry analysis. RESULTS: Obvious downregulation of miR-494 was observed in gastric cancer cells. Furthermore, we found that expression profile of miR-494 was associated with TRAIL-sensitivity in gastric cancer. Enforced expression of miR-494 was found to sensitize the gastric cancer cells to TRAIL-induced cytotoxicity. Mechanically, Luciferase reporter assays proved that survivin was the target of miR-494 in gastric cancer cells. Enforced expression of miR-494 decreased the expression of survivin, and thus promoted the TRAIL-induced mitochondria collapse and apoptosis pathway. CONCLUSION: MiR-494/survivin axis represents a potential mechanism which is responsible for TRAIL resistance in gastric cancer cells. Increasing the miR-494 expression may serve as a novel therapeutic strategy to sensitize gastric cancer cells to TRAIL treatment.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Gástricas/tratamento farmacológico , Survivina/genética , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Ligante Indutor de Apoptose Relacionado a TNF/uso terapêutico
7.
Small ; 14(34): e1801452, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30027622

RESUMO

Polystyrene-block-poly(2-vinylpyridine) (PS-b-P2VP) monoliths containing regular arrays of macropores (diameter ≈1.1 µm, depth ≈0.7 µm) at their surfaces are used to pattern substrates by patterning modes going beyond the functionality of classical solid elastomer stamps. In a first exemplary application, the macroporous PS-b-P2VP monoliths are employed as sacrificial templates for the deposition of NaCl nanocrystals and topographically patterned iridium films. One NaCl nanocrystal per macropore is formed by evaporation of NaCl solutions filling the macropores followed by iridium coating. Thermal PS-b-P2VP decomposition yields topographically patterned iridium films consisting of ordered arrays of hexagonal cells, each of which contains one NaCl nanocrystal. For the second exemplary application, spongy-continuous mesopore systems are generated in the macroporous PS-b-P2VP monoliths by selective-swelling induced pore generation. Infiltrating the spongy-continuous mesopore systems with ink allows capillary microstamping of continuous ink films with holes at the positions of the macropores onto glass slides compatible with advanced light microscopy. Capillary microstamping can be performed multiple times under ambient conditions without reinking and without quality deterioration of the stamped patterns. The macroporous PS-b-P2VP monoliths are prepared by double replication of primary macroporous silicon molds via secondary polydimethylsiloxane molds.

8.
Tumour Biol ; 35(1): 709-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23975371

RESUMO

Childhood acute lymphoblastic leukemia (ALL) is the leading cause of cancer-related deaths among children. Two recent genome-wide association studies and several replicated studies have provided convincing evidence that inherited genetic variation in ARID5B contributes to childhood ALL predisposition. In the present study, we performed a meta-analysis to systematically summarize the association between ARID5B genetic polymorphism and the risk for ALL. We conducted a search of case-control studies on the association of ARID5B genetic polymorphisms with susceptibility to ALL in PubMed, EMBASE, Wanfang database in China, and Chinese National Knowledge Infrastructure databases. Data from eligible studies were extracted for meta-analysis. ALL risk associated with ARID5B genetic polymorphism was estimated by pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). Nine articles including 13 case-control studies were included in the present meta-analysis. We found that rs10821936 polymorphism in ARID5B gene was associated with increased risk for ALL (P < 0.0001; OR = 1.27; 95%CI, 1.17-1.37). This meta-analysis suggests that ARID5B genetic polymorphism was associated with the increased risk of ALL.


Assuntos
Proteínas de Ligação a DNA/genética , Estudos de Associação Genética , Polimorfismo de Nucleotídeo Único , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores de Transcrição/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Razão de Chances , Leucemia-Linfoma Linfoblástico de Células Precursoras/etnologia , Viés de Publicação
9.
Tumour Biol ; 35(7): 7275-82, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24777337

RESUMO

There is cumulative evidence that stromal reaction in cancer has an important diagnostic and prognostic significance. The aims of this study were to analyze the expression of basic fibroblast growth factor (FGF-2), CD31, and α-smooth muscle actin (SMA) in esophageal cancer patients and to establish their significance as indicators of disease recurrence after definitive chemoradiation (CRT). Protein expressions of FGF-2, CD31, and SMA were evaluated by immunohistochemistry and Western blot analysis in 70 patients, 20 with esophageal squamous cell carcinoma (ESCC) and 50 with locally recurrent ESCC after definitive CRT. Twenty matched normal esophageal squamous epithelium were also studied as controls. Esophageal cancer tissues showed positive expression of FGF-2, CD31, and SMA; in contrast, FGF-2 expression was not detected and only little staining for CD31 and SMA was noted in normal epithelium. Protein levels of FGF-2, CD31, and SMA were significantly elevated in recurrent ESCC. Among the patients with locally recurrent disease, expression of FGF-2 and SMA was notably high in whom the tumor recurred locally within 24 months after definitive CRT. The 2- and 5-year local recurrence-free survival rate was 15.4 % and 0 in patients with high FGF-2 expression, compared with 45.8 and 33.3 % in those who expressed low FGF-2, respectively (P = 0.005). Of patients who expressed high SMA, the 2- and 5-year local recurrence-free survival rate was 21.7 and 8.7 %, respectively, compared to those with low SMA expression which was 37.0 and 22.2 %, respectively (P = 0.016). Overexpression of FGF-2 and SMA is associated with local recurrence and reduced recurrence-free survival after definitive CRT for ESCC. The data also suggest that targeting stromal cells may be an attractive approach for esophageal cancer therapy strategies.


Assuntos
Actinas/biossíntese , Neoplasias Esofágicas/genética , Fator 2 de Crescimento de Fibroblastos/biossíntese , Molécula-1 de Adesão Celular Endotelial a Plaquetas/biossíntese , Actinas/genética , Adulto , Idoso , Quimiorradioterapia , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Prognóstico
10.
Am J Cancer Res ; 14(4): 1501-1522, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726265

RESUMO

Considering the limited research and the prevailing evidence of STAT4's tumor-suppressing role in breast carcinoma (BC) or in breast radiotherapy (RT) sensitivity requires more in-depth exploration. Our study delves into how STAT4, a transcription factor, affects BC cell resistance to radiotherapy by regulating the MALAT1/miR-21-5p/THRB axis. Bioinformatics analysis was performed to predict the regulatory mechanisms associated with STAT4 in BC. Subsequently, we identified the expression profiles of STAT4, MALAT1, miR-21-5p, and THRB in various tissues and cell lines, exploring their interactions and impact on RT resistance in BC cells. Moreover, animal models were established with X-ray irradiation for further validation. We discovered that STAT4, which is found to be minimally expressed in breast carcinoma (BC) tissues and cell lines, has been associated with a poorer prognosis. In vitro cellular assays indicated that STAT4 could mitigate radiotherapy resistance in BC cells by transcriptional activation of MALAT1. Additionally, MALAT1 up-regulated THRB expression by adsorbing miR-21-5p. As demonstrated in vitro and in vivo, overexpressing STAT4 inhibited miR-21-5p and enhanced THRB levels through transcriptional activation of MALAT1, which ultimately contributes to the reversal of radiotherapy resistance in BC cells and the suppression of tumor formation in nude mice. Collectively, STAT4 could inhibit miR-21-5p and up-regulate THRB expression through transcriptional activation of MALAT1, thereby mitigating BC cell resistance to radiotherapy and ultimately preventing BC development and progression.

11.
J Pharm Sci ; 112(8): 2276-2284, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37062415

RESUMO

Mice are rarely used in pharmacokinetic (PK) studies of ocular therapeutics due to the small size of their eyes and challenges in drug administration, tissue collection, and analysis of drug concentrations. Therefore, ocular PK of protein therapeutics in mouse eye following intravitreal (IVT) administration is not known. Here, we have presented the first of its kind investigation, to study the PK of 4 different size non-binding protein therapeutics in mouse plasma, cornea/ICB, vitreous humor, retina, and posterior cup (including choroid) following IVT administration. Administered proteins include trastuzumab (150 kDa) and F(ab)2 (100 kDa), Fab, and scFv (27 kDa) fragments of trastuzumab. An imaging and injection apparatus suitable for performing small (50 nL) IVT injections in mice was developed, and techniques for enucleation of the eye and dissection of ocular tissues were developed. Furthermore, a sensitive enzyme-linked immunosorbent assay (ELISA) for detection of proteins in very small amounts of ocular tissues were developed. It was observed that elimination from the vitreous chamber was the primary driver of PK in the cornea/ICB, retina, posterior cup, and plasma. Trastuzumab displays first-order kinetics in the vitreous humor with a half-life of 18.8 h. F(ab)2, Fab, and ScFv show biphasic PK profiles with distribution phases becoming more rapid as molecular weight decreases, and terminal elimination becoming longer as molecular weight decreases, with terminal half-lives of 16.3, 20.6, and 48.9 h, respectively. The mean residence times of trastuzumab, F(ab)2, Fab, and scFv in the vitreous humor were 26.0, 12.2, 10.7, and 8.16 h, respectively. It was found that the mean residence time in vitreous humor doubles with an increase in molecular weight of ∼69 kDa. Interestingly, the PK of proteins measured in the un-injected eye suggest the presence of a pathway for drug transfer between the eyes, which needs to be further validated. Overall, the findings presented here pave the way for drug discovery and development studies of protein therapeutics for ophthalmic indications in mice.


Assuntos
Anticorpos Monoclonais , Olho , Camundongos , Animais , Anticorpos Monoclonais/metabolismo , Injeções Intravítreas , Olho/metabolismo , Corpo Vítreo/metabolismo , Trastuzumab , Fragmentos de Imunoglobulinas/metabolismo
12.
BMC Immunol ; 13: 40, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22788777

RESUMO

BACKGROUND: As a member of the TNF superfamily, TRAIL could induce human tumor cell apoptosis through its cognate death receptors DR4 or DR5, which can induce formation of the death inducing signaling complex (DISC) and activation of the membrane proximal caspases (caspase-8 or caspase-10) and mitochondrial pathway. Some monoclonal antibodies against DR4 or DR5 have been reported to have anti-tumor activity. RESULTS: In this study, we reported a novel mouse anti-human DR5 monoclonal antibody, named as LaDR5, which could compete with TRAIL to bind DR5 and induce the apoptosis of Jurkat cells in the absence of second cross-linking in vitro. Using computer-guided molecular modeling method, the 3-D structure of LaDR5 Fv fragment was constructed. According to the crystal structure of DR5, the 3-D complex structure of DR5 and LaDR5 was modeled using molecular docking method. Based on distance geometry method and intermolecular hydrogen bonding analysis, the key functional domain in DR5 was predicted and the DR5 mutants were designed. And then, three mutants of DR5 was expressed in prokaryotic system and purified by affinity chromatograph to determine the epitope of DR5 identified by LaDR5, which was consistent with the theoretical results of computer-aided analysis. CONCLUSIONS: Our results demonstrated the specific epitope located in DR5 that plays a crucial role in antibody binding and even antineoplastic bioactivity. Meanwhile, revealed structural features of DR5 may be important to design or screen novel drugs agonist DR5.


Assuntos
Anticorpos Monoclonais/imunologia , Região Variável de Imunoglobulina/imunologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/agonistas , Animais , Anticorpos Monoclonais/química , Complexo Antígeno-Anticorpo/imunologia , Apoptose , Sítios de Ligação de Anticorpos , Ligação Competitiva , Mapeamento de Epitopos , Humanos , Processamento de Imagem Assistida por Computador , Região Variável de Imunoglobulina/química , Células Jurkat , Camundongos , Camundongos Endogâmicos BALB C , Conformação Molecular , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Transdução de Sinais , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
13.
AAPS J ; 24(3): 62, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35501500

RESUMO

Here, we have investigated the effect of size of protein therapeutics on brain pharmacokinetics (PK) following systemic administration in rats. All tested proteins were derived from trastuzumab that do not bind to any targets in rats. PK data generated with F(ab)2 (100 kDa), Fab (50 kDa), and scFv (27 kDa) fragments of trastuzumab, along with published PK data for FcRn non-binding and wild-type trastuzumab (150 kDa), were used to establish a relationship between the protein size and brain exposure. A large-pore microdialysis system was used to measure the PK of proteins in the plasma, the interstitial fluid (ISF) at the striatum (ST), and the cerebrospinal fluid (CSF) at the lateral ventricle (LV) and cisterna magna (CM). Concentrations of all the proteins in plasma, brain homogenate, ISF, and CSF were measured using ELISA. When evaluating the effect of protein size in the absence of FcRn binding, we found a bell-shaped relationship between the size and ISF/plasma AUC ratio, where 100 kDa F(ab)2 demonstrated the highest exposure. A similar bell-shaped relationship was observed for the brain homogenate/plasma AUC ratio, with a peak at 50 kDa. The CSF/plasma AUC ratio at LV increased monotonously with a decrease in the size of proteins. We observed that the exposure of protein therapeutics in different regions of the brain could be significantly different and there could be optimal sizes of protein therapeutics to accomplish maximum/selective exposure in selected brain regions following systemic administration.


Assuntos
Encéfalo , Líquido Extracelular , Animais , Área Sob a Curva , Encéfalo/metabolismo , Preparações Farmacêuticas/metabolismo , Ratos , Trastuzumab/farmacocinética
14.
Oxid Med Cell Longev ; 2022: 5938688, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295718

RESUMO

Immune escape is a frequent occurrence, which limits the duration of antitumor immune responses to radiotherapy. Here, we aimed to ascertain the roles and underlying mechanisms of programmed death ligand 1 (PD-L1) in tolerance of breast cancer (BC) to radiotherapy. We first quantified microRNA-21 (miR-21) and PD-L1 expression in BC tissues and cells, followed by identification of the interactions between miR-21, PD-L1, and programmed cell death protein 4 (PDCD4). miR-21 knock-in mice were used to construct tumor-bearing models, which were then treated with anti-PD-L1 antibody and irradiation, followed by measurement of tumor growth and tumor immune escape. Finally, we evaluated the synergistic effects of radiotherapy and anti-PD-L1 antibody in vivo. The results showed increased miR-21 expression in BC tissues and cells, which was positively correlated with PD-L1 expression. The treatment with radiotherapy or anti-PD-L1 antibody in the miR-21 knock-in mice diminished tumor weight and volume, along with decreased CD3+CD8+ positive cells, serum IL-2 and IFN-γ levels, and lower PD-L1 expression, but augmented apoptosis of T and BC cells. Moreover, miR-21 significantly augmented PD-L1 expression via PI3K/Akt pathway activation by targeting PDCD4 in BC cells. Thus, radiotherapy and anti-PD-L1 antibody synergistically accelerated the therapeutic effect against BC in mice, thereby implicating a close interplay between radiotherapy, T cells, and the miR-21/PDCD4/PI3K/Akt/PD-L1 axis.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/radioterapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Linfócitos T/efeitos dos fármacos , Adulto , Idoso , Animais , Neoplasias da Mama/patologia , Modelos Animais de Doenças , Feminino , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Camundongos , Pessoa de Meia-Idade , Evasão Tumoral
15.
Front Cell Dev Biol ; 10: 817831, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35309941

RESUMO

The spindle assembly checkpoint (SAC) is a critical monitoring device in mitosis for the maintenance of genomic stability. Specifically, the SAC complex comprises several factors, including Mad1, Mad2, and Bub1. Ataxia-telangiectasia mutated (ATM) kinase, the crucial regulator in DNA damage response (DDR), also plays a critical role in mitosis by regulating Mad1 dimerization and SAC. Here, we further demonstrated that ATM negatively regulates the phosphorylation of Mad2, another critical component of the SAC, which is also involved in DDR. Mechanistically, we found that phosphorylation of Mad2 is aberrantly increased in ATM-deficient cells. Point-mutation analysis further revealed that Serine 195 mainly mediated Mad2 phosphorylation upon ATM ablation. Functionally, the phosphorylation of Mad2 causes decreased DNA damage repair capacity and is related to the resistance to cancer cell radiotherapy. Altogether, this study unveils the key regulatory role of Mad2 phosphorylation in checkpoint defects and DNA damage repair in ATM-deficient cells.

16.
Mater Today Bio ; 14: 100238, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35330634

RESUMO

Melanoma is a highly aggressive tumor located in the skin, with limited traditional therapies. In order to reduce the side effects caused by traditional administration method and amplify the killing effect of immune system against tumor cells, an in situ injectable hydrogel drug delivery system is developed for the first time which co-delivers doxorubicin (Dox) and imiquimod (R837) for the synergistic therapy of melanoma. The mechanical properties and stability of the hydrogel are characterized and the optimal doses of hydrogel and drugs are also identified. As a result, the co-delivery system effectively suppresses melanoma growth and metastatic progression both in vitro and in vivo. Further studies show that the co-delivery system causes immunogenic cell death, activation of antigen presenting cells, comprising dendritic cells and M1 macrophages, and secretion of related cytokines consisted of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ), subsequently with the activation of T lymphocytes and natural killer cells in spleen and tumor area. The co-delivery system also decreases the suppressive immune responses, including infiltration of M2 macrophages and secretion of interleukin-10 (IL-10), in vivo. Besides, other death modes are induced by the co-delivery system, including apoptosis and non-apoptotic cell death. In a word, this co-delivery system induces melanoma cell death directly and activates immune system for further tumor killing simultaneously, which shows probability for precise targeted tumor therapy.

17.
Int J Biol Sci ; 18(6): 2419-2438, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35414774

RESUMO

The most frequent genetic alterations of the TP53 gene in human cancer were reported. TP53 mutation gains new function as a target of genetic instability, which is associated with increased tumor progression and poor survival rate in patients. In this study, more than three hundred colorectal cancer patients' samples were firstly analyzed, and the results showed that patients with mutant p53 had higher levels of AKT phosphorylation and PD-L1 expression, which were next verified both in cell lines in vitro and patients' samples in vivo. Further studies demonstrated that the hotspot of mutant p53 directly binds to the promoter of PHLPP2 to inhibit its transcription, and resulting in down-regulating its protein expressional level. Subsequently, AKT was released and activated, promoting tumor proliferation and metastasis. In parallel, 4EBP1/eIF4E was identified as downstream executors of AKT to enhance the translational level of PD-L1, which decreased the activation of T cells. Besides, inhibiting AKT/mTOR pathway significantly suppressed PD-L1 expression, tumor growth, and immune escape in p53 mutated cells. In conclusion, mutant p53 achieved its Gain-of-Function by transcriptionally inhibiting PHLPP2 and activating AKT, which suppresses immune response and advances tumor growth. Thus, this study provides an excellent basis for a further understanding of the clinical treatment of neoplastic diseases for patients with mutant p53, with an emphasis on immunotherapy.


Assuntos
Antígeno B7-H1 , Proteínas Proto-Oncogênicas c-akt , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Linhagem Celular Tumoral , Mutação com Ganho de Função , Genes p53 , Humanos , Fosfoproteínas Fosfatases/genética , Fosfoproteínas Fosfatases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/genética
18.
ACS Appl Mater Interfaces ; 13(41): 49567-49579, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34619969

RESUMO

We report an optimized two-step thermopolymerization process carried out in contact with micropatterned molds that yields porous phenolic resin dual-use stamps with topographically micropatterned contact surfaces. With these stamps, two different parallel additive substrate manufacturing methods can be executed: capillary stamping and decal transfer microlithography. Under moderate contact pressures, the porous phenolic resin stamps are used for nondestructive ink transfer to substrates by capillary stamping. Continuous ink supply through the pore systems to the contact surfaces of the porous phenolic resin stamps enables multiple successive stamp-substrate contacts for lithographic ink deposition under ambient conditions. No deterioration of the quality of the deposited pattern occurs, and no interruptions for ink replenishment are required. Under a high contact pressure, porous phenolic resin stamps are used for decal transfer printing. In this way, the tips of the stamps' contact elements are lithographically transferred to counterpart substrates. The granular nature of the phenolic resin facilitates the rupture of the contact elements upon stamp retraction. The deposited phenolic resin micropatterns characterized by abundance of exposed hydroxyl groups are used as generic anchoring sites for further application-specific functionalizations. As an example, we deposited phenolic resin micropatterns on quartz crystal microbalance resonators and further functionalized them with polyethylenimine for preconcentration sensing of humidity and gaseous formic acid. We envision that also preconcentration coatings for other sensing methods, such as attenuated total reflection infrared spectroscopy and surface plasmon resonance spectroscopy, are accessible by this functionalization algorithm.

19.
Innovation (Camb) ; 2(1): 100088, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-34557742

RESUMO

Thin polymer coatings covering on porous substrates are a common composite structure required in numerous applications, including membrane separation, and there is a strong need to push the coating thicknesses down to the nanometer scale to maximize the performances. However, producing such ultrathin polymer coatings in a facile and efficient way remains a big challenge. Here, uniform ultrathin polymer covering films (UPCFs) are realized by a facile and general approach based on rapid solvent evaporation. By fast evaporating dilute polymer solutions spread on the surface of porous substrates, we obtain ultrathin coatings (down to ∼30 nm) exclusively on the top surface of porous substrates, forming UPCFs with a block copolymer of polystyrene-block-poly(2-vinyl pyridine) at room temperature or a homopolymer of poly(vinyl alcohol) (PVA) at elevated temperatures. Upon selective swelling of the block copolymer and crosslinking of PVA, we obtain highly permeable membranes delivering ∼2-10 times higher permeance in ultrafiltration and pervaporation than state-of-the-art membranes with comparable selectivities. We have invented a very convenient but highly efficient process for the direct preparation of defective-free ultrathin coatings on porous substrates, which is extremely desired in different fields in addition to membrane separation.

20.
AAPS J ; 23(6): 116, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34750690

RESUMO

The ocular pharmacokinetics (PK) of antibody-based therapies are infrequently studied in mice due to the technical difficulties in working with the small murine eye. This study is the first of its kind to quantitatively measure the PK of variously sized proteins in the plasma, cornea/ICB, vitreous humor, retina, and posterior cup (including choroid) of the mouse and to evaluate the relationship between molecular weight (MW) and antibody biodistribution coefficient (BC) to the eye. Proteins analyzed include trastuzumab (150 kDa), trastuzumab-vc-MMAE (T-vc-MMAE, 155 kDa), F(ab)2 (100 kDa), Fab (50 kDa), and scFv (27 kDa). As expected, ocular PK mirrored the systemic PK as plasma was the driving force for ocular exposure. For trastuzumab, T-vc-MMAE, F(ab)2, Fab, and scFv, respectively, the BCs in the cornea/ICB were 0.610%, 0.475%, 1.74%, 3.39%, and 13.7%; the BCs in the vitreous humor were 0.0198%, 0.0427%, 0.0934%, 0.234%, and 5.56%; the BCs for the retina were 0.539%, 0.230%, 0.704%, 2.44%, and 20.4%; the BCs for the posterior cup were 0.557%, 0.650%, 1.47%, 4.06%, and 13.9%. The relationship between BC and MW was best characterized by a log-log regression in which BC decreased as MW increased, with every doubling in MW leading to a decrease in BC by a factor of 3.44 × , 6.76 × , 4.74 × , and 3.43 × in cornea/ICB, vitreous humor, retina, and posterior cup, respectively. In analyzing the disposition of protein therapeutics to the eye, these findings enhance our understanding of the potential for ocular toxicity of systemically administered protein therapeutics and may aid in the discovery of systemically administered protein therapeutics for ocular disorders.


Assuntos
Olho/metabolismo , Imunoconjugados/farmacocinética , Fragmentos Fab das Imunoglobulinas/metabolismo , Oligopeptídeos/farmacocinética , Trastuzumab/farmacocinética , Animais , Imunoconjugados/administração & dosagem , Imunoconjugados/química , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Fragmentos de Imunoglobulinas/administração & dosagem , Fragmentos de Imunoglobulinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Peso Molecular , Oligopeptídeos/administração & dosagem , Oligopeptídeos/química , Distribuição Tecidual , Trastuzumab/administração & dosagem , Trastuzumab/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA