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1.
Angiogenesis ; 26(1): 19-36, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35829860

RESUMO

Tumor-induced lymphangiogenesis promotes the formation of new lymphatic vessels, contributing to lymph nodes (LNs) metastasis of tumor cells in both mice and humans. Vessel sprouting appears to be a critical step in this process. However, how lymphatic vessels sprout during tumor lymphangiogenesis is not well-established. Here, we report that S100A4 expressed in lymphatic endothelial cells (LECs) promotes lymphatic vessel sprouting in a growing tumor by regulating glycolysis. In mice, the loss of S100A4 in a whole body (S100A4-/-), or specifically in LECs (S100A4ΔLYVE1) leads to impaired tumor lymphangiogenesis and disrupted metastasis of tumor cells to sentinel LNs. Using a 3D spheroid sprouting assay, we found that S100A4 in LECs was required for the lymphatic vessel sprouting. Further investigations revealed that S100A4 was essential for the position and motility of tip cells, where it activated AMPK-dependent glycolysis during lymphatic sprouting. In addition, the expression of S100A4 in LECs was upregulated under hypoxic conditions. These results suggest that S100A4 is a novel regulator of tumor-induced lymphangiogenesis. Targeting S100A4 in LECs may be a potential therapeutic strategy for lymphatic tumor metastasis.


Assuntos
Células Endoteliais , Vasos Linfáticos , Camundongos , Humanos , Animais , Células Endoteliais/metabolismo , Vasos Linfáticos/metabolismo , Linfangiogênese/fisiologia , Metástase Linfática/patologia , Proteína A4 de Ligação a Cálcio da Família S100/genética , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo
2.
Nanomedicine ; 50: 102669, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36933756

RESUMO

Epidermal Growth Factor Receptor (EGFR) is a promising therapeutic target for triple-negative breast cancer (TNBC). Recently, specific EGFR-targeting peptide GE11-based delivery nano-system shows excellent potential because of its chemical versatility and good targeting ability. However, no further research focusing on the downstream of EGFR after binding with GE11 was explored. Hence, we tailor-designed a self-assembled nanoplatform named GENP using amphiphilic molecule of stearic acid-modified GE11. After loading doxorubicin (DOX), the resulted nanoplatform GENP@DOX demonstrated high loading efficiency and sustainable drug release. Importantly, our findings proved that GENP alone significantly suppressed the proliferation of MDA-MB-231 cells via EGFR-downstream PI3K/AKT signaling pathways, contributing to the synergistic treatment with its DOX release. Further work illustrated remarkable therapeutic efficacy both in orthotopic TNBC and its bone metastasis models with minimal biotoxicity. Together, the results highlight that our GENP-functionalized nanoplatform is a promising strategy for the synergistic therapeutic efficacy targeting EGFR-overexpressed cancer.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Fosfatidilinositol 3-Quinases , Linhagem Celular Tumoral , Receptores ErbB/química , Doxorrubicina/química , Peptídeos/farmacologia , Peptídeos/química
3.
J Cell Mol Med ; 26(10): 2921-2934, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35366056

RESUMO

N-α-Acetyltransferase 10 (NAA10) was reported to be involved in tumour invasion and metastasis in several of tumours. However, the role and mechanism of NAA10-mediated invasion and metastasis in oral squamous cell carcinoma (OSCC) remains undetermined. Herein, our study showed that NAA10 inhibits cell migration and invasion in vitro and attenuates the xenograft tumorigenesis in nude mice. Mechanistically, we demonstrated that there is a physical interaction between NAA10 and RelA/p65 in OSCC cells, thereby preventing RelA/p65-mediated transcriptional activation of Pirh2. Consequently, inhibition of Pirh2 increased p53 level and suppressed the expression of p53 downstream targets, matrix metalloprotein-2 (MMP-2) and MMP-9. Therefore, NAA10 may function as a tumour metastasis suppressor in the progression of OSCC by targeting Pirh2-p53 axis and might be a prognostic marker as well as a therapeutic target for OSCC.


Assuntos
Neoplasias Bucais , Acetiltransferase N-Terminal A , Acetiltransferase N-Terminal E , Carcinoma de Células Escamosas de Cabeça e Pescoço , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Neoplasias Bucais/patologia , Acetiltransferase N-Terminal A/metabolismo , Acetiltransferase N-Terminal E/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases
4.
J Gene Med ; 21(7): e3108, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31246328

RESUMO

Gene therapy has recently witnessed accelerated progress as a new therapeutic strategy with the potential to treat a range of inherited and acquired diseases. Billions of dollars have been invested in basic and clinical research on gene medicine, with ongoing clinical trials focused on cancer, monogenic diseases, cardiovascular diseases and other refractory diseases. Advances addressing the inherent challenges of gene therapy, particularly those related to retaining the delivery efficacy and minimizing unwanted immune responses, provide the basis for the widespread clinical application of gene medicine. Several types of genes delivered by viral or non-viral delivery vectors have demonstrated encouraging results in both animals and humans. As augmented by clinical indications, gene medicine techniques have rapidly become a promising alternative to conventional therapeutic strategies because of their better clinical benefit and lower toxicities. Their application in the clinic has been extensive as a result of the approval of many gene therapy drugs in recent years. In this review, we provide a comprehensive overview of the clinical translation of gene medicine, focusing on the key events and latest progress made regarding clinical gene therapy products. We also discuss the gene types and non-viral materials with respect to developing gene therapeutics in clinical trials.


Assuntos
Técnicas de Transferência de Genes/tendências , Terapia Genética/tendências , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , Doenças Transmissíveis/genética , Doenças Transmissíveis/terapia , Técnicas de Transferência de Genes/efeitos adversos , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/terapia , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Vetores Genéticos/química , Humanos , Neoplasias/genética , Neoplasias/terapia
5.
J Oral Pathol Med ; 48(8): 686-695, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31134698

RESUMO

BACKGROUND: This study aims to explore the associations between N-α-acetyltransferase 10 protein (Naa10p) and p53-induced protein with a RING-H2 domain (Pirh2) expression and clinicopathological characteristics in oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemistry was performed to detect Naa10p and Pirh2 levels containing 118 OSCC specimens, and additional analyses were used to determine correlations between Naa10p and Pirh2 expressions, generate survival curves, and perform univariate and multivariate statistical analyses. Further, quantitative real-time PCR (qRT-PCR) and western blot were employed to examine Naa10p and Pirh2 expression level in OSCC patients' samples. We further validated the result using RNAseq data from The Cancer Genome Atlas (TCGA) and mRNA array data from GSE31056 and GSE30784. RESULTS: Naa10p and Pirh2 are overexpression, and the protein level of Naa10p was negatively correlated with that of Pirh2 in OSCC tissues. Multivariate Cox proportional hazard regression analysis showed that positive Naa10p expression and negative Pirh2 expression were both independent good prognostic factors for OSCC patients. Furthermore, the Naa10p-positive/Pirh2-negative group has the best prognosis among all OSCC patients. Results from qRT-PCR showed the higher expression level of Naa10 and lower expression level of Pirh2 in tumor tissues than adjacent normal tissues. TCGA database and data from GSE31056 and GSE30784 showed the similar result. The correlation analysis showed that the mRNA level of Naa10 was negatively correlated that of Pirh2. CONCLUSION: The expression of Naa10p is negatively correlated with that of Pirh2, and positive Naa10p and negative Pirh2 might be independent biomarkers for better OSCC prognoses.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Neoplasias Bucais/diagnóstico , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Ubiquitina-Proteína Ligases/genética , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Prognóstico , RNA Mensageiro
6.
J Oral Pathol Med ; 47(9): 830-835, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30028540

RESUMO

BACKGROUND: N-α-acetyltransferase 10 protein (Naa10p) is a potential prognostic biomarker that modulates the phenotypes of several cancer types. Carcinoembryonic antigen (CEA) is currently the most well-known biomarker for the detection of epithelial malignancies. Our objective was to evaluate the clinical value of Naa10p, CEA, and their combined detection for diagnosis of oral squamous cell carcinoma (OSCC). METHODS: This study included 202 individuals: 112 patients with OSCC, 30 patients with oral premalignant lesions (OPMLs), and 60 cancer-free and without OPML patients as control. Naa10p and CEA were determined in serum and saliva samples utilizing enzyme-linked immunosorbent assays. RESULTS: Salivary and serum levels of Naa10p and CEA in OSCC patients were significantly higher than those detected in OPML and the control groups, although patients with OPMLs also showed increased salivary and serum Naa10p and CEA levels as compared to the control group. Salivary Naa10p level in OSCC patients is correlated with the degree of differentiation and lymph node metastasis, and serum Naa10p level is specifically correlated with patient age. Additionally, salivary CEA level is correlated with the clinical stage and lymph node metastasis, whereas serum CEA level is correlated with lymph node metastasis. The sensitivity, specificity, positive predictive value, and negative predictive value of combined detection were greater than any single detection. CONCLUSIONS: Combined use of salivary Naa10p and CEA as tumor markers for OSCC was more sensitive than serum Naa10p and CEA. These results indicated that combined detection of salivary Naa10p and CEA improved diagnostic performance and early detection rate for OSCC.


Assuntos
Biomarcadores Tumorais/análise , Biomarcadores Tumorais/sangue , Antígeno Carcinoembrionário/análise , Antígeno Carcinoembrionário/sangue , Carcinoma de Células Escamosas/diagnóstico , Detecção Precoce de Câncer , Neoplasias Bucais/diagnóstico , Acetiltransferase N-Terminal A/análise , Acetiltransferase N-Terminal A/sangue , Acetiltransferase N-Terminal E/análise , Acetiltransferase N-Terminal E/sangue , Saliva/química , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
7.
Mol Pharm ; 13(2): 663-76, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26695934

RESUMO

Combination treatment through simultaneous delivery of DNA and anticancer drugs with nanoparticles has been demonstrated to be an elegant and efficient approach for cancer therapy. Herein, we employed a combination therapy for eliminating both the tumor cells and intratumoral neovascular network based on the nanoplatform we designed. Pigment epithelium-derived factor (PEDF) gene, a powerful antiangiogenic agent, and the clinically widely used chemotherapy agent paclitaxel (PTX) were simultaneously encapsulated in the same nanoparticle by a modified double-emulsion solvent evaporation method. The dual-drug-loaded nanoparticles (D/P-NPs) exhibited a uniform spherical morphology and released PTX and PEDF gene in a sustained manner. D/P-NPs showed an enhanced antitumor effect on C26 and A549 cells and a stronger inhibitory activity on proliferation of HUVECs. Moreover, D/P-NPs could dramatically elevate the PEDF expression levels in both C26 and A549 cells in comparison with PEDF gene loaded nanoparticles and significantly promote the cellular uptake of PTX. Additionally, microtubules were stabilized and G2/M phase arrest along with a higher subG1 cell population was induced by D/P-NPs in contrast to PTX or PTX loaded nanoparticles. Besides, D/P-NPs showed sustained release of PTX and PEDF gene in tumors as well as long-term gene expression. A significantly improved anticancer effect was also demonstrated in a C26 subcutaneous tumor model using this combinational therapy. D/P-NPs could sharply reduce the microvessel density and significantly promoted tumor cell apoptosis in vivo. More importantly, the in vivo distribution, serological and biochemical analysis, and H&E staining revealed that D/P-NPs had no obvious toxicity. Our study suggested that this novel polymeric nanomedicine had great potential for improving the therapeutic efficacy of combined gene/chemotherapy of cancer.


Assuntos
Neoplasias do Colo/terapia , Sistemas de Liberação de Medicamentos , Proteínas do Olho/genética , Neoplasias Pulmonares/terapia , Nanomedicina , Nanopartículas/administração & dosagem , Fatores de Crescimento Neural/genética , Paclitaxel/farmacologia , Polímeros/química , Serpinas/genética , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Terapia Combinada , Imunofluorescência , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Polímeros/administração & dosagem , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Int J Mol Sci ; 17(12)2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27898022

RESUMO

Hypertension has become a significant global public health concern and is also one of the most common risk factors of cardiovascular disease. Recent studies have shown the promising result of peptides inhibiting angiotensin converting enzyme (ACE) in lowering the blood pressure in both animal models and humans. However, the oral bioavailability and continuous antihypertensive effectiveness require further optimization. Novel nanoparticle-based drug delivery systems are helpful to overcome these barriers. Therefore, a poly-(lactic-co-glycolic) acid nanoparticle (PLGANPs) oral delivery system, of the antihypertensive small peptides Val-Leu-Pro-Val-Pro (VLPVP, VP5) model, was developed in this study and its antihypertensive effect was investigated in spontaneously hypertensive rats (SHRs) for the first time. The obtained VP5 nanoparticles (VP5-NPs) showed a small particle size of 223.7 ± 2.3 nm and high entrapment efficiency (EE%) of 87.37% ± 0.92%. Transmission electronic microscopy (TEM) analysis showed that the nanoparticles were spherical and homogeneous. The optimal preparation of VP5-NPs exhibited sustained release of VP5 in vitro and a 96 h long-term antihypertensive effect with enhanced efficacy in vivo. This study illustrated that PLGANPs might be an optimal formulation for oral delivery of antihypertensive small peptides and VP5-NPs might be worthy of further development and use as a potential therapeutic strategy for hypertension in the future.


Assuntos
Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/química , Animais , Masculino , Oligopeptídeos/química , Tamanho da Partícula , Ratos , Ratos Endogâmicos SHR
9.
Am J Cancer Res ; 14(5): 2408-2423, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38859859

RESUMO

γ-Synuclein (SNCG) has various biological functions associated with tumorigenesis. However, the role of SNCG in oral squamous cell carcinoma (OSCC) remains unknown. In this study, we found that SNCG expression is associated with the malignancy of OSCC. We showed that SNCG promotes cell proliferation and inhibits apoptosis in OSCC. Mechanistically, we demonstrated for the first time, that SNCG interacts with ERK1/2 and promotes its phosphorylation leading to activation of the JAK2/STAT5b signaling pathway. Subsequent experiments with STAT5b interference and ERK1/2 inhibitor treatment reversed the effects of SNCG on OSCC cell proliferation, apoptosis and cell cycle progression. Our findings suggest that SNCG functions as an oncogene in OSCC by targeting the JAK2/STAT5b axis and thus may be a potential new prognostic marker and therapeutic target in OSCC.

10.
J Mol Graph Model ; 129: 108731, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38430696

RESUMO

The energy stability and electronic structural of graphene and defective graphene oxide (GO) parallel to the surface of LiFePO4 (010) were theoretically investigated by using first-principles density functional theory calculations within the DFT + U framework. The calculated formation energy shows that GO coating on the surface of LiFePO4 (010) is energetically favorable and has higher bond strength compared to graphene. The calculation of the electronic structure indicates that the emergence of band in-gap states originates from graphene coating, with adsorbed O atoms contributing significantly above the Fermi level. Electron density difference indicate that GO stands on the LFP (010) surface through C-O and Fe-O bonds, rather than relying on van der Waals forces placed parallel to the LFP crystal, with the chemical bond at the LFP/GO interface (Fe-O-C) both anchoring the coated carbon layer and promoting electron conductivity at the interface. In addition, LFP/GO shows superior electrochemical performance, Atomic Populations suggests that the average Fe-O bonding on the surface of LiFePO4 (010) was clearly changed after graphene or GO coating, which led to the expansion of Li+ channels and favored the migration insertion and extraction of Li+.


Assuntos
Grafite , Carbono , Condutividade Elétrica , Eletrônica
11.
J Gastrointest Oncol ; 15(3): 1198-1213, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38989424

RESUMO

Background: Cholangiocarcinoma (CCA), a highly lethal tumor of the hepatobiliary system originating from bile duct epithelium, can be divided into the intrahepatic, hilar, and extrahepatic types. Due to its insidious onset and atypical early clinical symptoms, the overall prognosis is poor. One of the important factors contributing to the poor prognosis of CCA is the occurrence of perineural invasion (PNI), but the specific mechanisms regarding how it contributes to the occurrence of PNI are still unclear. The main purpose of this study is to explore the molecular mechanism leading to the occurrence of PNI and provide new ideas for clinical treatment. Methods: CCA cell lines and Schwann cells (SCs) were stimulated to observe the changes in cell behavior. SCs cocultured with tumor supernatant and SCs cultured in normal medium were subjected to transcriptome sequencing to screen the significantly upregulated genes. Following this, the two types of tumor cells were cultured with SC supernatant, and the changes in behavior of the tumor cells were observed. Nonobese diabetic-severe combined immunodeficiency disease (NOD-SCID) mice were injected with cell suspension supplemented with nerve growth factor (NGF) via the sciatic nerve. Four weeks later, the mice were euthanized and the tumor sections were removed and stained. Results: Nerve invasion by tumor cells was common in CCA tissues. SCs were observed in tumor tissues, and the number of SCs in tumor tissues and the degree of PNI were much higher than were those in normal tissues or tissues without PNI. The overall survival time was shorter in patients with CCA with PNI than in patients without PNI. SCs were enriched in CCA tissues, indicating the presence of PNI and associated with poor prognosis in CCA patients. CCA was found to promote NGF secretion from SCs in vitro. After the addition of exogenous NGF in CCA cell culture medium, the proliferation activity and migration ability of CCA cells were significantly increased, suggesting that SCs can promote the proliferation and migration of CCA through the secretion of NGF. NGF, in turn, was observed to promote epithelial-mesenchymal transition in CCA through tropomyosin receptor kinase A (TrkA), thus promoting its progression. Tumor growth in mice shows that NGF can promote PNI in CCA. Conclusions: In CCA, tumor cells can promote the secretion of NGF by SCs, which promotes the progression of CCA and PNI by binding to its high-affinity receptor TrkA, leading to poor prognosis.

12.
MedComm (2020) ; 5(6): e605, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38868328

RESUMO

During the ageing process, TNF-α can promote the expansion of myeloid-derived suppressor cells (MDSCs). However, it remains unclear which receptor(s) of TNF-α are involved in and how they modulate this process. Here, we report that TNFR2 hyperexpression induced by either TNF-α or IL-6, two proinflammatory factors of senescence-associated secretory phenotype (SASP), causes cellular apolarity and differentiation inhibition in aged MDSCs. Ex vivo overexpression of TNFR2 in young MDSCs inhibited their polarity and differentiation, whereas in vivo depletion of Tnfr2 in aged MDSCs promotes their differentiation. Consequently, the age-dependent increase of TNFR2 versus unaltered TNFR1 expression in aged MDSCs significantly shifts the balance of TNF-α signaling toward the TNFR2-JNK axis, which accounts for JNK-induced impairment of cell polarity and differentiation failure of aged MDSCs. Consistently, inhibiting JNK attenuates apolarity and partially restores the differentiation capacity of aged MDSCs, suggesting that upregulated TNFR2/JNK signaling is a key factor limiting MDSC differentiation during organismal ageing. Therefore, abnormal hyperexpression of TNFR2 represents a general mechanism by which extrinsic SASP signals disrupt intrinsic cell polarity behavior, thereby arresting mature differentiation of MDSCs with ageing, suggesting that TNFR2 could be a potential therapeutic target for intervention of ageing through rejuvenation of aged MDSCs.

13.
J Mol Graph Model ; 125: 108604, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37598604

RESUMO

In this study, the thermodynamic stability, embedding voltage, volume change rate, electronic structure properties, mechanical properties and lithium-ion diffusion characteristics of the Mn, N co-doped LiFePO4 material are investigated using a first-principles approach based on density generalization theory. The results show that the doped system has a low formation energy and the material meets the thermodynamic stability criteria. During the de-lithium process, the volume change rate of the doped material decreases and the cycling performance is improved, but the battery energy density decreases slightly. It is also found that the doping of N led to the transformation of the material from a p-type semiconductor to an N-type semiconductor, while the doping of Mn and N lead to the creation of impurity bands, narrowing of the band gap and an increase in conductivity. At the same time, Mn, N co-doping greatly improve the ductility of the material, suppress the generation of microcracks, and reduce the possibility of shear deformation. In addition, it is noteworthy that the lithium-ion diffusion energy barrier of the doped system is reduced, which predicts an increase in the diffusion rate of lithium ions in the doped system.


Assuntos
Fontes de Energia Elétrica , Lítio , Difusão , Condutividade Elétrica , Eletrônica
14.
J Mol Graph Model ; 121: 108456, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36966662

RESUMO

To understand the effects of pressure on microstructural evolution, a molecular dynamics simulation study has been performed under pressures of 0-20 GPa for liquid Fe-S-Bi alloy during the solidification process. The variations in the radial distribution function, average atomic energy, and H-A bond index of the cooling system are analyzed. The rapid solidification process of liquid Fe-S-Bi alloy into crystalline and amorphous alloys is investigated from different perspective. The results show that the glass transition temperature Tg, the sizes of the MnS atomic groups, and major bond-types increase almost linearly with increasing pressure. In addition, the recovery rate of Bi increased first and then decreased with increasing pressure, reaching a peak of 68.97% under 5 GPa. The manganese sulfide compound is embedded in the alloy with a spindle-shape under 20 GPa, which is a better clusters structure.


Assuntos
Ligas , Simulação de Dinâmica Molecular , Vidro , Manganês , Temperatura
15.
J Mol Graph Model ; 118: 108354, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36209593

RESUMO

In order to research the effect pattern of MnS inclusions on free-cutting steel, we study the microstructure evolution, the damage mechanism and the mechanical properties in free-cutting steel in the presence of MnS inclusions. Spindle shaped MnS is added as inclusions within the free-cutting steel. The mechanical properties were found to change when inclusions were present. The gained results show that the formation of voids causing fracture starts from the interface inside the matrix close to the MnS. From the point of view of nanocomposite strength, the main effect of MnS inclusions is related to stress concentration, leading to the effect of increased stresses near the interface between the interior of the matrix and the inclusions. The inclusions have lower Young's modulus and lower dislocation activity, resulting in smaller deformation of the alloy system, larger interfacial stress concentrations and earlier hole formation. The maximum strain and stress regions of the alloy also appear near the MnS inclusions, which leads to the formation of defects near the MnS inclusions and then fracture of the alloy. MnS inclusions adversely affect the tensile properties of the alloy, such as Young's modulus, yield stress and yield strain. By comparing the stress-strain curves of single crystal iron and alloy containing MnS inclusions, it is indicated that the yield strength of the latter decreases. Slip bands and dislocation lines are first generated around the MnS inclusion, and the phase transition is induced from the original single BCC structure to FCC, HCP and amorphous structures, and the atoms of FCC, HCP and amorphous structures increase with increasing strain, while those of BCC structure decrease, especially after yield strain. This study is significant for understanding the effect of inclusions on the mechanical laws and fracture mechanisms of the alloy.

16.
Int J Biol Macromol ; 240: 124324, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37023874

RESUMO

CCL21, a secondary lymphoid tissue chemokine, plays an important role in generating an effective anti-tumor immune response. In this study, a genetically modified CCL21 was developed by inserting a pH low insertion peptide to establish a CCL21-rich microenvironment for tumors. The fusion tag thioredoxin (Trx) was designed and fused at the N-terminal of the recombinant protein to protect it from being irrevocably misfolded in microbial host cells. The prokaryotic expression vector pET32a-CCL21-pHLIP was constructed and successfully expressed in E. coli BL21 (DE3) with a soluble expression form and a molecular weight of ~35 kDa. The induction conditions were optimized to obtain an extremely high yield of 6.7 mg target protein from 31.1 mg total protein. The 6xHis tagged Trx-CCL21-pHLIP was purified using Ni-NTA resin, and it was confirmed using SDS-PAGE and Western blot analyses. Consequently, the Trx-CCL21-pHLIP protein was successfully displayed on the cancer cell surface in a weak acidic microenvironment and showed the same ability as CCL21 in recruiting CCR7-positive cells. Additionally, the CCL21 fusion protein with or without Trx tag showed similar functions. Therefore, the study implies the feasibility of directing a modular genetic method for the development of protein-based drugs.


Assuntos
Escherichia coli , Neoplasias , Proteínas Recombinantes de Fusão/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Quimiocina CCL21/genética , Quimiocina CCL21/metabolismo , Proteínas Recombinantes/metabolismo , Membrana Celular , Concentração de Íons de Hidrogênio
17.
RSC Adv ; 13(17): 11269-11277, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37057265

RESUMO

Exosomes exhibit great potential as novel therapeutics for tissue regeneration, including cell migration and angiogenesis. However, the limited intracellular delivery efficiency of exosomes might reduce their biological effects. Here, exosomes secreted by adipose-derived mesenchymal stem cells were recombined with fluorinated peptide dendrimers (FPG3) to form the fluorine-engineered exosomes (exo@FPG3), which was intended to promote the cytosolic release and the biological function of exosomes. The mass ratio of FPG3 to exosomes at 5 was used to investigate its cellular uptake efficiency and bioactivity in HUVECs, as the charge of exo@FPG3 tended to be stable even more FPG3 was applied. It was found that exo@FPG3 could enter HUVECs through a variety of pathways, in which the clathrin-mediated endocytosis played an important role. Compared with exosomes modified with peptide dendrimers (exo@PG3) and exosomes alone, the cellular uptake efficiency of exo@FPG3 was significantly increased. Moreover, exo@FPG3 significantly enhanced the angiogenesis and migration of HUVECs in vitro as compared to exo@PG3 and exosomes. It is concluded that surface fluorine modification of exosomes with FPG3 is conducive to the cellular uptake and bioactivity of the exosome, which provides a novel strategy for engineered exosomes to enhance the biological effects of exosome-based drug delivery.

18.
Life Sci ; 326: 121790, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37211345

RESUMO

AIMS: PARP inhibitors (PARPi) are known to exert anti-tumor effects in patients with BRCA-mutated (BRCAmut) or homologous recombination (HR)-deficient cancer, but recent clinical investigations have suggested that this treatment may also be beneficial in patients with HR-proficient tumors. In this study, we aimed to investigate how PARPi exerts anti-tumor effects in non-BRCAmut tumors. MAIN METHODS: BRCA wild-type, HR-deficient-negative ID8 and E0771 murine tumor cells were treated in vitro and in vivo with olaparib, a clinically approved PARPi. The effects on tumor growth in vivo were determined in immune-proficient and -deficient mice and alterations of immune cell infiltrations were analyzed with flow cytometry. Tumor-associated macrophages (TAMs) were further investigated with RNA-seq and flow cytometry. In addition, we confirmed olaparib's effect on human TAMs. KEY FINDINGS: Olaparib did not affect HR-proficient tumor cell proliferation and survival in vitro. However, olaparib significantly decreased tumor growth in C57BL/6 and SCID-beige mice (defective in lymphoid development and NK cell activity). Olaparib increased macrophage numbers in the tumor microenvironment, and their depletion diminished the anti-tumor effects of olaparib in vivo. Further analysis revealed that olaparib improved TAM-associated phagocytosis of cancer cells. Notably, this enhancement was not solely reliant on the "Don't Eat Me" CD47/SIRPα signal. In addition, compared to monotherapy, the concomitant administration of αCD47 antibodies with olaparib improved tumor control. SIGNIFICANCE: Our work provides evidence for broadening the application of PARPi in HR-proficient cancer patients and paves the way for developing novel combined immunotherapy to upgrade the anti-tumor effects of macrophages.


Assuntos
Neoplasias , Inibidores de Poli(ADP-Ribose) Polimerases , Humanos , Camundongos , Animais , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Macrófagos Associados a Tumor , Antígeno CD47/genética , Camundongos Endogâmicos C57BL , Camundongos SCID , Recombinação Homóloga , Fagocitose , Linhagem Celular Tumoral , Ftalazinas/farmacologia , Microambiente Tumoral
19.
J Control Release ; 357: 133-148, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36972863

RESUMO

Spleen is an ideal site for initiating and amplifying antigen-specific immune response. However, spleen-selective antigen delivery has limited tumor therapeutic efficacy owing to an inadequate cytotoxic T-cell immune response. In this study, we designed a spleen-selective mRNA vaccine that delivered unmodified mRNA and Toll-like Receptor (TLR) agonists to the spleen after systemic administration, resulting in a sufficient and persistent antitumor cellular immune response with potent tumor immunotherapeutic efficacy. To establish potent tumor vaccines (sLNPs-OVA/MPLA), we co-loaded stearic acid doped lipid nanoparticles with ovalbumin (OVA)-coding mRNA and TLR4 agonists (MPLA). We found that sLNPs-OVA/MPLA facilitated tissue-specific mRNA expression in the spleen after intravenous injection and elicited enhanced adjuvant activity with Th1 immune responses by activating multiple TLRs. In a prophylactic mouse model, sLNPs-OVA/MPLA induced a potent antigen-specific cytotoxic T cell immune response and ultimately prevented the growth of EG.7-OVA tumors with persistent immune memory protection. In addition, sLNPs-OVA/MPLA effectively delayed the tumor growth of EG.7-OVA subcutaneously transplanted lymphoma and lung metastasis formation of B16F10-OVA intravenously injected melanoma. This study showed that the co-delivery of mRNA antigens and appropriate TLR agonists could significantly improve the antitumor immunotherapeutic efficacy of spleen-targeted mRNA vaccines via synergistic immunostimulation and Th1 immune responses.


Assuntos
Baço , Receptor 4 Toll-Like , Animais , Camundongos , Receptor 4 Toll-Like/genética , Imunização , Adjuvantes Imunológicos , Imunidade Celular , Antígenos , Ovalbumina , Camundongos Endogâmicos C57BL
20.
Materials (Basel) ; 15(14)2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35888200

RESUMO

In this paper, a model generation algorithm for non-equal diameter particles with a specified probability density distribution is proposed. Based on considering the randomness of the size and distribution of the particles, the compact stacking of the particles is realized by the compactness algorithm, and then the spatial distribution of the tightly compacted particles is made to meet the random distribution of the specified probability density and the specified volume fraction by the filtering algorithm. The computational efficiency and effectiveness of the algorithm are verified, and the effects of the particle size and volume fraction on the distribution are analyzed. Finally, the proposed model has been used to study the permeability of a titanium porous filter cartridge. The results show that the size and location of the particle samples that are generated by the proposed algorithm follow specified probability distributions according to the requirements, and the volume fraction can be adjusted. Compared with the traditional algorithm, the computational effort and complexity are reduced. The resultant model can be used to study the permeability of porous materials and provide modeling support for structural optimization and further simulation of porous materials.

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