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1.
Nature ; 599(7886): 599-604, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34819685

RESUMO

Amorphous materials inherit short- and medium-range order from the corresponding crystal and thus preserve some of its properties while still exhibiting novel properties1,2. Due to its important applications in technology, amorphous carbon with sp2 or mixed sp2-sp3 hybridization has been explored and prepared3,4, but synthesis of bulk amorphous carbon with sp3 concentration close to 100% remains a challenge. Such materials inherit the short-/medium-range order of diamond and should also inherit its superior properties5. Here, we successfully synthesized millimetre-sized samples-with volumes 103-104 times as large as produced in earlier studies-of transparent, nearly pure sp3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary. The material synthesized consists of many randomly oriented clusters with diamond-like short-/medium-range order and possesses the highest hardness (101.9 ± 2.3 GPa), elastic modulus (1,182 ± 40 GPa) and thermal conductivity (26.0 ± 1.3 W m-1 K-1) observed in any known amorphous material. It also exhibits optical bandgaps tunable from 1.85 eV to 2.79 eV. These discoveries contribute to our knowledge about advanced amorphous materials and the synthesis of bulk amorphous materials by high-pressure and high-temperature techniques and may enable new applications for amorphous solids.

2.
Drug Resist Updat ; 66: 100907, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527888

RESUMO

The binding of programmed death-1 (PD-1) on the surface of T cells and PD-1 ligand 1 (PD-L1) on tumor cells can prevent the immune-killing effect of T cells on tumor cells and promote the immune escape of tumor cells. Therefore, immune checkpoint blockade targeting PD-1/PD-L1 is a reliable tumor therapy with remarkable efficacy. However, the main challenges of this therapy are low response rate and acquired resistance, so that the outcomes of this therapy are usually unsatisfactory. This review begins with the description of biological structure of the PD-1/PD-L1 immune checkpoint and its role in a variety of cells. Subsequently, the therapeutic effects of immune checkpoint blockers (PD-1 / PD-L1 inhibitors) in various tumors were introduced and analyzed, and the reasons affecting the function of PD-1/PD-L1 were systematically analyzed. Then, we focused on analyzing, sorting out and introducing the possible underlying mechanisms of primary and acquired resistance to PD-1/PD-L1 blockade including abnormal expression of PD-1/PD-L1 and some factors, immune-related pathways, tumor immune microenvironment, and T cell dysfunction and others. Finally, promising therapeutic strategies to sensitize the resistant patients with PD-1/PD-L1 blockade treatment were described. This review is aimed at providing guidance for the treatment of various tumors, and highlighting the drug resistance mechanisms to offer directions for future tumor treatment and improvement of patient prognosis.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias , Receptor de Morte Celular Programada 1 , Humanos , Antígeno B7-H1 , Resistência a Medicamentos , Imunoterapia , Microambiente Tumoral
3.
Mol Ther ; 30(2): 606-620, 2022 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-34601133

RESUMO

Hepatocellular carcinoma (HCC) is frequently characterized by metabolic and immune remodeling in the tumor microenvironment. We previously discovered that liver-specific deletion of fructose-1, 6-bisphosphatase 1 (FBP1), a gluconeogenic enzyme ubiquitously suppressed in HCC tissues, promotes liver tumorigenesis and induces metabolic and immune perturbations closely resembling human HCC. However, the underlying mechanisms remain incompletely understood. Here, we reported that FBP1-deficient livers exhibit diminished amounts of natural killer (NK) cells and accelerated tumorigenesis. Using the diethylnitrosamine-induced HCC mouse model, we analyzed potential changes in the immune cell populations purified from control and FBP1-depleted livers and found that NK cells were strongly suppressed. Mechanistically, FBP1 attenuation in hepatocytes derepresses an zeste homolog 2 (EZH2)-dependent transcriptional program to inhibit PKLR expression. This leads to reduced levels of PKLR cargo proteins sorted into hepatocyte-derived extracellular vesicles (EVs), dampened activity of EV-targeted NK cells, and accelerated liver tumorigenesis. Our study demonstrated that hepatic FBP1 depletion promotes HCC-associated immune remodeling, partly through the transfer of hepatocyte-secreted, PKLR-attenuated EVs to NK cells.


Assuntos
Carcinoma Hepatocelular , Vesículas Extracelulares , Neoplasias Hepáticas , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Comunicação , Vesículas Extracelulares/metabolismo , Hepatócitos/metabolismo , Células Matadoras Naturais/metabolismo , Neoplasias Hepáticas/metabolismo , Camundongos , Microambiente Tumoral
4.
BMC Med Educ ; 23(1): 670, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723452

RESUMO

BACKGROUND: The purpose of this study was to explore the applicability of application effect of head-mounted mixed reality (MR) equipment combined with a three-dimensional (3D) printed model in neurosurgical ventricular and haematoma puncture training. METHODS: Digital Imaging and Communications in Medicine (DICOM) format image data of two patients with common neurosurgical diseases (hydrocephalus and basal ganglia haemorrhage) were imported into 3D Slicer software for 3D reconstruction, saved, and printed using 3D printing to produce a 1:1-sized head model with real person characteristics. The required model (brain ventricle, haematoma, puncture path, etc.) was constructed and imported into the head-mounted MR device, HoloLens, and a risk-free, visual, and repeatable system was designed for the training of junior physicians. A total of 16 junior physicians who studied under this specialty from September 2020 to March 2022 were selected as the research participants, and the applicability of the equipment and model during training was evaluated with assessment score sheets and questionnaires after training. RESULTS: According to results of the assessment and questionnaire, the doctors trained by this system are more familiar with the localization of the lateral anterior ventricle horn puncture and the common endoscopic surgery for basal ganglia haemorrhage, as well as more confident in the mastery of these two operations than the traditional training methods. CONCLUSIONS: The use of head-mounted MR equipment combined with 3D printing models can provide an ideal platform for the operation training of young doctors. Through holographic images created from the combination of virtual and real images, operators can be better immersed in the operation process and deepen their understanding of the operation and related anatomical structures. The 3D printed model can be repeatedly reproduced so that doctors can master the technology, learn from mistakes, better achieve the purpose of teaching and training, and improve the effect of training.


Assuntos
Realidade Aumentada , Hemorragia dos Gânglios da Base , Neurocirurgia , Humanos , Punções , Impressão Tridimensional , Hematoma
5.
Molecules ; 28(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836790

RESUMO

Src homology 2 domain-containing phosphatase 2 (SHP2) is an attractive target for cancer therapy due to its multifaceted roles in both tumor and immune cells. Herein, we designed and synthesized a novel series of proteolysis targeting chimeras (PROTACs) using a SHP2 allosteric inhibitor as warhead, with the goal of achieving SHP2 degradation both inside the cell and in vivo. Among these molecules, compound P9 induces efficient degradation of SHP2 (DC50 = 35.2 ± 1.5 nM) in a concentration- and time-dependent manner. Mechanistic investigation illustrates that the P9-mediated SHP2 degradation requires the recruitment of the E3 ligase and is ubiquitination- and proteasome-dependent. P9 shows improved anti-tumor activity in a number of cancer cell lines over its parent allosteric inhibitor. Importantly, administration of P9 leads to a nearly complete tumor regression in a xenograft mouse model, as a result of robust SHP2 depletion and suppression of phospho-ERK1/2 in the tumor. Hence, P9 represents the first SHP2 PROTAC molecule with excellent in vivo efficacy. It is anticipated that P9 could serve not only as a new chemical tool to interrogate SHP2 biology but also as a starting point for the development of novel therapeutics targeting SHP2.


Assuntos
Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Humanos , Animais , Camundongos , Neoplasias/tratamento farmacológico , Linhagem Celular , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteólise
6.
Zhonghua Nan Ke Xue ; 29(12): 986-991, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38639950

RESUMO

OBJECTIVE: To explore the effect of a novel transurethral thulium laser vapoenucleation of the prostate with low-power conventional pulse mode (LP-ThuVEP) on sexual function in patients with benign prostatic hyperplasia (BPH). METHODS: 89 BPH patients admitted to Department of Urology, Jintan People's Hospital, Affiliated to Jiangsu University, from January 2022 to June 2023 were selected and randomly divided into the LP-ThuLEP group (45 cases) and the transurethral plasma kinetic resection of the prostate (TUPKRP) group (44 cases). Perioperative indicators were recorded, and the IPSS, Qmax, Qavg, PVR, and QoL of the two groups of patients before surgery and 3 months and 6 months after surgery were comparatively analyzed. The effect of surgery on male sexual function was evaluated through the International Index of Erectile Function-5 (IIEF-5) score and the Male Sexual Health Questionnaire-Ejaculatory Dysfunction (MSHQ-EjD) score. RESULTS: Compared with the TUPKRP group, the LP-ThuVEP group had no statistically significant difference in operation time (P>0.05), but there were statistical differences in bladder irrigation time and indwelling urinary catheter time (P<0.05) and significant statistical differences in the decrease in hemoglobin on the day of surgery and the disappearance time of gross hematuria induced by defecation after surgery (P<0.001). The perioperative complications of the two groups were comparable. Among the urinary tract symptom indicators, the LP-ThuVEP group had statistically significant differences in IPSS score, QoL score, and PVR compared with the TUPKRP group 3 months after surgery (P<0.05). In terms of male sexual function, there was a statistical difference in IIEF-5 scores between the two groups at 3 months and 6 months after surgery (P<0.05); Except that there was no statistical difference in the ejaculation-related satisfaction scores between the two groups at 3 months after surgery (P>0.05), there had all significant statistical differences in ejaculation function and satisfaction scores between and within the groups at 3 months and 6 months after surgery (P<0.001). CONCLUSION: Compared with TUPKRP, the LP-ThuVEP can also effectively relieve urinary tract obstruction caused by BPH and has the advantages of less damage and faster recovery of erectile function and ejaculatory function of patients.


Assuntos
Disfunção Erétil , Terapia a Laser , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Masculino , Próstata/cirurgia , Hiperplasia Prostática/cirurgia , Disfunção Erétil/cirurgia , Qualidade de Vida , Resultado do Tratamento
7.
Angew Chem Int Ed Engl ; 62(22): e202303818, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36973833

RESUMO

Protein tyrosine phosphatase 1B (PTP1B) and T-cell protein tyrosine phosphatase (TC-PTP) play non-redundant negative regulatory roles in T-cell activation, tumor antigen presentation, insulin and leptin signaling, and are potential targets for several therapeutic applications. Here, we report the development of a highly potent and selective small molecule degrader DU-14 for both PTP1B and TC-PTP. DU-14 mediated PTP1B and TC-PTP degradation requires both target protein(s) and VHL E3 ligase engagement and is also ubiquitination- and proteasome-dependent. DU-14 enhances IFN-γ induced JAK1/2-STAT1 pathway activation and promotes MHC-I expression in tumor cells. DU-14 also activates CD8+ T-cells and augments STAT1 and STAT5 phosphorylation. Importantly, DU-14 induces PTP1B and TC-PTP degradation in vivo and suppresses MC38 syngeneic tumor growth. The results indicate that DU-14, as the first PTP1B and TC-PTP dual degrader, merits further development for treating cancer and other indications.


Assuntos
Neoplasias , Proteína Tirosina Fosfatase não Receptora Tipo 2 , Humanos , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias/tratamento farmacológico , Fosforilação , Imunoterapia
8.
J Appl Microbiol ; 132(4): 3293-3301, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34897902

RESUMO

AIMS: The study aimed to investigate the prevalence and conservation of endocarditis and biofilm-associated pili (ebp) genes in Enterococcus faecalis originated from animals and the potential of developing Ebp into serological diagnostic and vaccine targets. METHODS AND RESULTS: In this work, we investigated the prevalence and conservation of ebp genes in 116 strains of E. faecalis originated from animals by using PCR and sequencing methods. The results demonstrated the presence of ebp genes (ebpA, ebpB and ebpC) in all 116 strains of E. faecalis, and their amino acid homology ranges from 96.6% to 100.0%. Moreover, the phylogenetic analysis of ebp genes in all 164 E. faecalis strains (including 48 reference strains) revealed that ebp genes show no significant correlation with species origins and regions of E. faecalis, indicating that ebp genes are conserved features in E. faecalis, even though it evolved under environmental pressures from various regions and origins. Given that EbpA1 as a part of the adhesion protein EbpA has immunogenicity, we further determined whether amino acid mutations have effects on the function and 3D structure of EbpA1. The results showed that two of the 26 mutations, at amino acids positions 178 and 387, had deleterious effects on the biological function of EbpA1 protein, while all mutations had no effect on the 3D structure or binding pockets of EbpA1 protein. CONCLUSIONS: This study suggests that ebp genes are prevalent and conserved in E. faecalis originated from diverse animal origins and regions. EbpA1 could be a potential target for serological diagnosis and vaccine development to prevent E. faecalis infection. SIGNIFICANCE AND IMPACT OF STUDY: The current study provides data to support further research on Ebp as a serological diagnostic and vaccine target against E. faecalis infection.


Assuntos
Enterococcus faecalis , Infecções por Bactérias Gram-Positivas , Animais , Aderência Bacteriana/genética , Enterococcus faecalis/metabolismo , Proteínas de Fímbrias/genética , Filogenia , Prevalência
9.
Int J Mol Sci ; 24(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36613893

RESUMO

Transmissible gastroenteritis virus (TGEV) is a coronavirus causing diarrhea with high incidence in swine herds. Its persistent infection might lead to epithelial-mesenchymal transition (EMT) of swine intestinal epithelial cells, followed by subsequent infections of other pathogens. Enterococcus faecalis (E. faecalis) is a member of the enteric microorganisms and an opportunistic pathogen. There is no report of secondary E. faecalis infection to TGEV, even though they both target to the intestinal tracts. To investigate the interactions between TGEV and E. faecalis, we set up an in vitro infection model by the swine IPEC-J2 cells. Dynamic changes of cell traits, including EMT and cell motility, were evaluated through qPCR, Western blot, electronic microscopy, scratch test, Transwell migration test and invasion test, respectively. The adhesion and invasion tests of E. faecalis were taken to verify the impact of the preceding TGEV infection. The cell morphology and molecular marker evaluation results showed that the TGEV persistent infection induced EMT on IPEC-J2 cells; increased cellular motility and invasion potential were also observed. Spontaneously, the expression levels of fibronectin (FN) and the membrane protein integrin-α5, which are dominant bacterial receptors on IPEC-J2 cells, were upgraded. It indicated that the bacteria E. faecalis adhered to IPEC-J2 cells through the FN receptor, and then invaded the cells by binding with the integrin-α5, suggesting that both molecules were critical for the adhesion and invasion of E. faecalis to IPEC-J2 cells. Additionally, it appeared that E. faecalis alone might trigger certain EMT phenomena, implying a vicious circle might occur. Generally, bacterial and viral co-infections are frustrating yet common in both human and veterinary medicines, and our observations on enteric TGEV and E. faecalis interactions, especially the diversity of bacterial invasion strategies, might provide new insights into the mechanisms of E. faecalis pathogenicity.


Assuntos
Infecções Bacterianas , Vírus da Gastroenterite Transmissível , Animais , Humanos , Suínos , Enterococcus faecalis , Infecção Persistente , Intestinos , Células Epiteliais/microbiologia , Integrinas
10.
BMC Endocr Disord ; 21(1): 225, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34774043

RESUMO

BACKGROUND: Prolactinoma is the major cause of hyperprolactinemia, and dopamine agonists (DAs) are generally the first-line treatment for them. Several studies have reviewed the recurrent rate of hyperprolactinemia after DAs withdrawal. However, few of them have concerned the recurrence risk of prolactinoma following the withdrawal of DAs. METHODS: Three medical databases, PubMed, EMBASE and Cochrane library, were retrieved up to February, 14, 2021 to identify studies related to recurrence of prolactinoma and withdrawal of DAs. Statistical analyses including meta-analysis, sensitivity analysis, meta-regression, funnel plot and Egger test were performed through software R. RESULTS: A total of 3225 studies were retrieved from the three data bases, and 13 studies consisted of 616 patients and 19 arms were finally included in this systematic analysis. There was no significant heterogeneity among the included studies, and fixed effect model was thus used. The pooled recurrence proportion of prolactinoma after withdrawal of DA was 2% with a 95% confidence interval (CI) of 1-3%. CONCLUSION: Our study showed a very low recurrent rate of prolactinomas after DAs withdrawal. Much more prospective studies with larger cases and longer follow-up period are encouraged to confirm our finding. TRIAL REGISTRATION: Registration number CRD42021245888 (PROSPERO).


Assuntos
Desprescrições , Agonistas de Dopamina/uso terapêutico , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Hipofisárias/tratamento farmacológico , Prolactinoma/tratamento farmacológico , Bromocriptina/uso terapêutico , Cabergolina/uso terapêutico , Humanos
11.
Br J Neurosurg ; : 1-7, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33605815

RESUMO

OBJECTIVE: Percutaneous microballoon compression (PMC) is a simple and effective surgical procedure for the treatment of trigeminal neuralgia. The difficulty with this surgery is related to accurate and quick foramen ovale puncture. In this study, we compared the application of personalized 3D-printed guides and the traditional puncture method in trigeminal PMC surgery. METHOD: Data from 40 patients with primary trigeminal neuralgia treated with PMC between June 2017 and August 2019 were analyzed retrospectively. Personalized 3D-printed jigs were used to assist foramen ovale puncture in 20 patients, and Hartel positioning was used for puncture in 20 patients. Three-dimensional reconstruction was performed preoperatively using 3DSlicer software to understand the size of the foramen ovale and positioning of related anatomical structures. Based on the reconstruction, personalized surgical paths were created for the jig plate-assisted treatment group, and the printed jig plate was applied to the surgery through 3D printing to explore the surgical effect. RESULTS: Foramen ovale puncture was successful in all patients. Better results were achieved with guides than with the traditional method in terms of the foramen ovale puncture time (p < 0.01), total operation time (p < 0.01), and number of computed tomography scans (p < 0.01). The efficacy of surgery and postoperative complications did not differ between groups (p = 1). CONCLUSIONS: The use of personalized 3D-printed guides enables accurate puncture positioning in PMC, and improves the success rate of surgery, shortens the operation time, and reduces surgical risk, which has broad prospects in clinical application.

12.
J Am Chem Soc ; 142(16): 7584-7590, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32250116

RESUMO

According to the laws of thermodynamics, materials normally exhibit contraction or expansion along the directions of the applied pressure or tension. Here, we show that a man-made cocrystal of a metallofullerene and highly energetic cubane, with strained sp3 bonding, may exhibit an anomalous negative volume compressibility. In this cocrystal, the freely rotating fullerene Sc3N@C80 acts as a structural building block while static cubane molecules fill the lattice interstitial sites. Under high pressure, Sc3N@C80 keeps stable and preserves the crystalline framework of the materials, while the cubane undergoes a progressive configurational transformation above 6.5 GPa, probably promoted by charge transfer from fullerene to cubane. A further configurational change of the cubane into a low-density configuration at higher pressure results in an anomalous pressure-driven lattice expansion of the cocrystal (∼1.8% volume expansion). Such unusual negative compressibility has previously only been predicted by theory and suggested to appear in mechanical metamaterials.

13.
Small ; 16(24): e2001714, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32419373

RESUMO

The fabrication of silicon (Si) anode materials derived from high silica-containing plants enables effective utilization of subsidiary agricultural products. However, the electrochemical performances of synthesized Si materials still require improvement and thus need further structural design and morphology modifications, which inevitably increase preparation time and economic cost. Here, the conversion of corn leaves into Si anode materials is reported via a simple aluminothermic reduction reaction without other modifications. The obtained Si material inherits the structural characteristics of the natural corn leaf template and has many inherent advantages, such as high porosity, amorphous/crystalline mixture structure, and high-valence SiOx residuals, which significantly enhance the material's structural stability and electrode adhesive strength, resulting in superior electrochemical performances. Rate capability tests show that the material delivers a high capacity of 1200 mA h g-1 at 8 A g-1 current density. After 300 cycles at 0.5 A g-1 , the material maintains a high specific capacity of 2100 mA h g-1 , with nearly 100% capacity retention during long-term cycling. This study provides an economical route for the industrial production of Si anode materials for Lithium-Ion batteries.


Assuntos
Lítio , Silício , Biomassa , Eletrodos , Folhas de Planta , Zea mays
14.
Phys Rev Lett ; 124(6): 065701, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109099

RESUMO

Graphite is known to transform into diamond under dynamic compression or under combined high pressure and high temperature, either by a concerted mechanism or by a nucleation mechanism. However, these mechanisms fail to explain the recently reported discovery of diamond formation during ambient temperature compression combined with shear stress. Here we report a new transition pathway for graphite to diamond under compression combined with shear, based on results from both theoretical simulations and advanced experiments. In contrast to the known model for thermally activated diamond formation under pressure, the shear-induced diamond formation takes place during the decompression process via structural transitions. At a high pressure with large shear, graphite transforms into ultrastrong sp^{3} phases whose structures depend on the degree of shear stress. These metastable sp^{3} phases transform into either diamond or graphite upon decompression. Our results explain several recent experimental observations of low-temperature diamond formation. They also emphasize the importance of shear stress for diamond formation, providing new insight into the graphite-diamond transformation mechanism.

15.
Nanotechnology ; 28(3): 035704, 2017 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-27941221

RESUMO

Onion-like carbon nanospheres (OCNSs) with an average diameter of 43 nm were produced on a large scale via a combustion method and examined as an anode material for lithium ion batteries. The OCNSs exhibit a remarkable electrochemical cycling behavior and a capacity much higher than that of graphite. The capacity increases significantly with increasing charge-discharge cycles and reaches a value of 178% of the initial value (from 586 mA h g-1to 1045 mA h g-1) after 200 cycles. Further investigation provides unambiguous experimental evidence that such a remarkable capacity increase is related to the stable onion-like structure of the OCNSs and to the existence of large numbers of disordered/short graphitic fragments, which gradually provide more active sites for Li ion storage. The unique electrochemical performance of OCNSs provides a new way to design a high-performance anode material for rechargeable batteries.

16.
J Clin Invest ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38842946

RESUMO

Aberrant activation of RAS-MAPK signaling is common in cancer, and efforts to inhibit pathway components have yielded drugs with promising clinical activities. Unfortunately, treatment-provoked adaptive resistance mechanisms inevitably develop, limiting their therapeutic potential. As a central node essential for receptor tyrosine kinase mediated RAS activation, SHP2 has emerged as an attractive cancer target. Consequently, many SHP2 allosteric inhibitors are now in clinical testing. Here we discovered a previously unrecognized off-target effect associated with SHP2 allosteric inhibitors. We found that these inhibitors accumulate in the lysosome and block autophagic flux in a SHP2-independent manner. We showed that off-target autophagy inhibition by SHP2 allosteric inhibitors contributes to their anti-tumor activity. We also demonstrated that SHP2 allosteric inhibitors harboring this off-target activity not only suppress oncogenic RAS signaling but also overcome drug resistance such as MAPK rebound and protective autophagy in response to RAS-MAPK pathway blockage. Finally, we exemplified a therapeutic framework that harnesses both the on- and off-target activities of SHP2 allosteric inhibitors for improved treatment of mutant RAS driven and drug resistant malignancies such as pancreatic and colorectal cancers. Brief Summary: SHP2 allosteric inhibitors elicit off-target autophagy blockade that can be exploited for improved treatment of RAS-driven and drug-resistant cancers.

17.
J Med Chem ; 67(11): 8817-8835, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38768084

RESUMO

Together with protein tyrosine kinases, protein tyrosine phosphatases (PTPs) control protein tyrosine phosphorylation and regulate numerous cellular functions. Dysregulated PTP activity is associated with the onset of multiple human diseases. Nevertheless, understanding of the physiological function and disease biology of most PTPs remains limited, largely due to the lack of PTP-specific chemical probes. In this study, starting from a well-known nonhydrolyzable phosphotyrosine (pTyr) mimetic, phosphonodifluoromethyl phenylalanine (F2Pmp), we synthesized 7 novel phosphonodifluoromethyl-containing bicyclic/tricyclic aryl derivatives with improved cell permeability and potency toward various PTPs. Furthermore, with fragment- and structure-based design strategies, we advanced compound 9 to compound 15, a first-in-class, potent, selective, and bioavailable inhibitor of human CDC14A and B phosphatases. This study demonstrates the applicability of the fragment-based design strategy in creating potent, selective, and bioavailable PTP inhibitors and provides a valuable probe for interrogating the biological roles of hCDC14 phosphatases and assessing their potential for therapeutic interventions.


Assuntos
Inibidores Enzimáticos , Fosfotirosina , Humanos , Fosfotirosina/metabolismo , Fosfotirosina/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Relação Estrutura-Atividade , Proteínas Tirosina Fosfatases não Receptoras/antagonistas & inibidores , Proteínas Tirosina Fosfatases não Receptoras/metabolismo , Proteínas Tirosina Fosfatases não Receptoras/química , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Proteínas Tirosina Fosfatases/metabolismo , Estrutura Molecular , Disponibilidade Biológica
18.
Br J Pharmacol ; 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38116815

RESUMO

Contemporary strategies in cancer immunotherapy, despite remarkable success, remain constrained by inherent limitations such as suboptimal patient responses, the emergence of drug resistance, and the manifestation of pronounced adverse effects. Consequently, the need for alternative strategies for immunotherapy becomes clear. Protein tyrosine phosphatases (PTPs) wield a pivotal regulatory influence over an array of essential cellular processes. Substantial research has underscored the potential in targeting PTPs to modulate the immune responses and/or regulate antigen presentation, thereby presenting a novel paradigm for cancer immunotherapy. In this review, we focus on recent advances in genetic and biological validation of several PTPs as emerging targets for immunotherapy. We also highlight recent development of small molecule inhibitors and degraders targeting these PTPs as novel cancer immunotherapeutic agents.

19.
Microbiol Spectr ; : e0358122, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36847543

RESUMO

Chronic infections caused by polymicrobial biofilms are often difficult to treat effectively, partially due to the elevated tolerance of polymicrobial biofilms to antimicrobial treatments. It is known that interspecific interactions influence polymicrobial biofilm formation. However, the underlying role of the coexistence of bacterial species in polymicrobial biofilm formation is not fully understood. Here, we investigated the effect of the coexistence of Enterococcus faecalis, Escherichia coli O157:H7, and Salmonella enteritidis on triple-species biofilm formation. Our results demonstrated that the coexistence of these three species enhanced the biofilm biomass and led to restructuring of the biofilm into a tower-like architecture. Furthermore, the proportions of polysaccharides, proteins, and eDNAs in the extracellular matrix (ECM) composition of the triple-species biofilm were significantly changed compared to those in the E. faecalis mono-species biofilm. Finally, we analyzed the transcriptomic profile of E. faecalis in response to coexistence with E. coli and S. enteritidis in the triple-species biofilm. The results suggested that E. faecalis established dominance and restructured the triple-species biofilm by enhancing nutrient transport and biosynthesis of amino acids, upregulating central carbon metabolism, manipulating the microenvironment through "biological weapons," and activating versatile stress response regulators. Together, the results of this pilot study reveal the nature of E. faecalis-harboring triple-species biofilms with a static biofilm model and provide novel insights for further understanding interspecies interactions and the clinical treatment of polymicrobial biofilms. IMPORTANCE Bacterial biofilms possess distinct community properties that affect various aspects of our daily lives. In particular, biofilms exhibit increased tolerance to chemical disinfectants, antimicrobial agents, and host immune responses. Multispecies biofilms are undoubtedly the dominant form of biofilms in nature. Thus, there is a pressing need for more research directed at delineating the nature of multispecies biofilms and the effects of the properties on the development and survival of the biofilm community. Here, we address the effects of the coexistence of Enterococcus faecalis, Escherichia coli, and Salmonella enteritidis on triple-species biofilm formation with a static model. In combination with transcriptomic analyses, this pilot study explores the potential underlying mechanisms that lead to the dominance of E. faecalis in triple-species biofilms. Our findings provide novel insights into the nature of triple-species biofilms and indicate that the composition of multispecies biofilms should be a key consideration when determining antimicrobial treatments.

20.
Eur J Pharmacol ; 938: 175444, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36462734

RESUMO

Temozolomide (TMZ) is the recommended drug for glioblastoma (GBM) treatment, but its clinical effect is restricted due to drug resistance. This research studies the effects of long non-coding RNA (lncRNA) ZBED3-AS1 and its related molecules on acquired TMZ resistance in glioblastoma (GBM). ZBED3-AS1 was identified to be downregulated in TMZ-resistant GBM cells by analyzing GSE113510 and GSE100736 datasets. ZBED3-AS1 downregulation was detected in TMZ-resistant GBM tissues and cell lines (U251/TMZ and U87/TMZ). ZBED3-AS1 knockdown promoted, whereas its overexpression suppressed TMZ resistance, viability and mobility, and glycolytic activity of TMZ-resistant cells. ZBED3-AS1 bound to Spi-1 proto-oncogene (SPI1) but did not affect its expression. Instead, it blocked SPI1-mediated transcriptional activation of thrombomodulin (THBD). SPI1 and THBD increased TMZ resistance and glycolysis in TMZ-resistant cells. Either ZBED3-AS1 overexpression or SPI1 knockdown in U87/TMZ cells blocked the growth of orthotopic and subcutaneous xenograft tumors in nude mice. In conclusion, this study demonstrates that ZBED3-AS1 downregulation and THBD activation is linked to increased TMZ resistance and glycolysis in GBM cells.


Assuntos
Neoplasias Encefálicas , Glioblastoma , RNA Longo não Codificante , Camundongos , Animais , Humanos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , RNA Longo não Codificante/metabolismo , Regulação para Baixo , Camundongos Nus , Neoplasias Encefálicas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Linhagem Celular Tumoral , Proliferação de Células , Glicólise , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo
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