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1.
Chin Med J (Engl) ; Publish Ahead of Print2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33410632
2.
J Am Chem Soc ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33410701

RESUMO

We describe an enantioselective total synthesis of the nonahydroxylated sesquiterpenoid euonyminol, the dihydro-ß-agarofuran nucleus of the macrocyclic terpenoid alkaloids known as the cathedulins. Key features of the synthetic sequence include a highly diastereoselective intramolecular alkene oxyalkylation to establish the C10 quaternary center, an intramolecular aldol-dehydration to access the tricyclic scaffold of the target, a tandem lactonization-epoxide opening to form the trans-C2-C3 vicinal diol residue, and a late-stage diastereoselective α-ketol rearrangement. The synthesis provides the first synthetic access to enantioenriched euonyminol and establishes a platform to synthesize the cathedulins.

3.
Pharmacol Res ; : 105411, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33401002

RESUMO

The incidence rate of adenocarcinoma of the esophagogastric junction (AEG) is increasing worldwide with poor prognosis and unclear pathogenesis. Trametes robiniophila Murr. (Huaier), a traditional Chinese medicine has been used in the clinical treatment of a variety of solid tumors, including AEG. However, its anticancer components and molecular mechanisms are still unclear. In our previous studies, we have found that Huaier n-butanol extract (HBE) shows the most potent anticancer activity among different extracts. In the present study, we aimed to investigate the clinical relevance of p-MEK expression in AEG patients and the role of the MEK/ERK signaling pathway in the anti-AEG efficacy of HBE in vitro and in vivo. We herein demonstrate that p-MEK expression in AEG tissues was significantly higher than that in paracancerous tissues and correlated with a poor prognosis in AEG patients. We further found that HBE inhibited the colony formation, migration, and invasion in AEG cell lines in a concentration-dependent manner in vitro. HBE also suppressed the growth of AEG xenograft tumors without causing any host toxicity in vivo. Mechanistically, HBE caused the inactivation of the MEK/ERK signaling pathway by dephosphorylating MEK1 at S298, ERK1 at T202, and ERK2 at T185 and modulating the expression of EMT-related proteins. In summary, our results demonstrate that the high expression of p-MEK may be an independent factor of poor prognosis in patients with AEG. The clinically used anticancer drug Huaier may exert its anti-AEG efficacy by inhibiting the MEK/ERK signaling pathway.

4.
Biosens Bioelectron ; 176: 112944, 2021 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-33421761

RESUMO

Combining electrochemiluminescence (ECL) with nanozyme amplification provides unique advantages for the detection of antibiotic residues. Herein, a molecularly imprinted chloramphenicol (CAP) sensor was established based on aggregation-induced (AI)-ECL and nanozyme amplification. Covalent organic framework materials with AI-ECL groups (COF-AI-ECL) and nanozyme Co3O4 were synthesised as the signal element and the amplification element, respectively. Subsequently, using CAP as a template molecule, a molecularly imprinted polymer (MIP) was fabricated on the electrode surface modified with COF-AI-ECL and Co3O4. The ECL signal of COF-AI-ECL was catalytically amplified by Co3O4, whereas CAP effectively quenched this signal. Consequently, the ECL signal was controlled by the elution and adsorption of CAP by the MIP, thus establishing a new method for CAP detection. Unlike traditional ECL reagent, COF-AI-ECL exhibited a stable and strong ECL signal. Therefore, COF-AI-ECL in combination with the MIP provided greater sensitivity and enhanced selectivity. The linear range of the developed CAP sensor was 5 × 10-13 to 4 × 10-10 mol/L, with a detection limit of 1.18 × 10-13 mol/L. Moreover, the recoveries range of 85.0%-106.2% were obtained for the detection of CAP in real honey, milk, and chicken samples, indicating the potential of this sensor design for the detection of trace antibiotic residues in food safety applications.

5.
Heart ; 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33419880

RESUMO

OBJECTIVE: Tricuspid regurgitation (TR) is a common valvular heart disease with unsatisfactory medical therapeutics and high surgical mortality. The present study aims to evaluate the safety and effectiveness of transcatheter tricuspid valve replacement (TTVR) in high-risk patients with severe TR. METHODS: This was a compassionate multicentre study. Between September 2018 and November 2019, 46 patients with TR who were not suitable for surgery received compassionate TTVR under general anaesthesia and the guidance of trans-oesophageal echocardiography and fluoroscopy in four institutions. Access to the tricuspid valve was obtained via a minimally invasive thoracotomy and transatrial approach. Patients' data at baseline, before discharge, 30 days and 6 months after the procedure were collected. RESULTS: All patients had severe TR with vena contracta width of 12.6 (11.0, 14.5) mm. Procedural success (97.8%) was achieved in all but one case with right ventricle perforation. The procedural time was 150.0 (118.8, 180.0) min. Intensive care unit time was 2.0 (1.0, 4.0) days. 6-month mortality was 17.4%. Device migration occurred in one patient (2.4%) during follow-up. Transthoracic echocardiography at 6 months after operation showed TR was significantly reduced (none/trivial in 33, mild in 4 and moderate in 1) and the primary safety end point was achieved in 38 cases (82.6%). Patients suffered from peripheral oedema and ascites decreased from 100.0% and 47.8% at baseline to 2.6% and 0.0% at 6 months. CONCLUSIONS: The present study showed TTVR was feasible, safe and with low complication rates in patients with severe TR.

6.
Free Radic Biol Med ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33418113

RESUMO

Adriamycin (ADR) resistance poses a significant challenge for successfully treating breast cancer (BCa). The mechanism underlying intrinsically acquisition of the resistance remains to be fully elucidated. Here, we describe that small extracellular vesicles (sEVs) mediated Hsp70 transfer is implicated in ADR resistance. The resistant cells derived sEVs were incubated with sensitive cells, thereby transmitting the resistant phenotype to the recipient cells. The internalization of the sEVs in the recipient cells and sEV-mediated Hsp70 transfer into mitochondria were examined by confocal microscope and transmission electron microscopy (TEM). Oxygen consumption rate (OCR) incorporated with extracellular acidification rate (ECAR) was quantified by Seahorse XF Analyzer. Mechanistically, sEVs transported Hsp70, leading to increased reactive oxygen species (ROS) and impaired mitochondria in the recipient cells, thereby inhibiting respiration but promoting glycolysis. The sEVs effect on the metabolism of the recipient cells was alleviated by silencing Hsp70 in sEVs donor cells. The aspect of sEV-Hsp70 on drug-resistant transmission was further validated by tumor zebrafish xenografts. The finding from this work suggests that sEV-mediated Hsp70 intercellular delivery enhances ADR resistance mainly through reprogramming the recipient cell energy metabolism.

7.
Nanoscale ; 13(1): 124-130, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33326538

RESUMO

All-inorganic lead halide perovskites (AILHPs) quantum dots (QDs) have been widely investigated as promising materials for optoelectronic applications because of their outstanding luminescence properties. Lead leakage, a common impurity and environmental pollution source that majorly hinders the commercialization of lead halide perovskite devices, has lately attracted considerable attention. Its detrimental influence on the luminescence performance has been widely reported. However, an in-depth experimental study of the chemistry geometry relating to lead leakage in CsPbBr3 QDs has been rarely reported to date. Herein, combining real-time (scanning) transmission electron microscopy ((S)TEM) with density functional theory calculations, we showed detailed atomic and electronic structure study of the phase boundaries in CsPbBr3 QDs during the lead leakage process. A phenomenon of two-phase coexistence was reported to be linked with the lead precipitating in CsPbBr3 QDs. A phase boundary between the Ruddlesden-Popper (RP) phase and conventional orthorhombic perovskite was developed when the lead particle was aggregating in the QDs. Our results suggested that in considering the detrimental exciton quenching process not only the role of lead nanoparticles should be considered but also the influence of the phase boundary on electron-hole transport is worthy of attention. The direct visualization of the delicate atomic and electronic structures associated with lead aggregation in CsPbBr3 sheds light on how the leakage process influences the luminescence performance and provides a potential route for suppressing the generation of environmentally harmful byproducts for advanced devices.

8.
AIDS ; 35(1): 91-99, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33048879

RESUMO

OBJECTIVE: To evaluate changes in weight and BMI in adults with HIV-1 at 1 and 2 years after starting an antiretroviral regimen that included doravirine, ritonavir-boosted darunavir, or efavirenz. DESIGN: Post-hoc analysis of pooled data from three randomized controlled trials. METHODS: We evaluated weight change from baseline, weight gain at least 10%, and increase in BMI after 48 and 96 weeks of treatment with doravirine, ritonavir-boosted darunavir, or efavirenz-based regimens. Risk factors for weight gain and metabolic outcomes associated with weight gain were also examined. RESULTS: Mean (and median) weight changes were similar for doravirine [1.7 (1.0) kg] and ritonavir-boosted darunavir [1.4 (0.6) kg] and were lower for efavirenz [0.6 (0.0) kg] at week 48 but were similar across all treatment groups at week 96 [2.4 (1.5), 1.8 (0.7), and 1.6 (1.0) kg, respectively]. No significant differences between treatment groups were found in the proportion of participants with at least 10% weight gain or the proportion with BMI class increase at either time point. Low CD4 T-cell count and high HIV-1 RNA at baseline were associated with at least 10% weight gain and BMI class increase at both timepoints, but treatment group, age, sex, and race were not. CONCLUSION: Weight gains over 96 weeks were low in all treatment groups and were similar to the average yearly change in adults without HIV-1. Significant weight gain and BMI class increase were similar across the treatment groups and were predicted by low baseline CD4 T-cell count and high baseline HIV-1 RNA.

9.
Arch Pharm (Weinheim) ; 354(1): e2000223, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32985011

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) has developed numerous mechanisms of virulence and strategies to evade the human immune system, and it can be transmitted between humans, animals, and the environment. Thus, MRSA is an important cause of morbidity and mortality in both hospitals and in the community, creating an urgent demand for the development of novel anti-MRSA candidates. The 1,2,4-triazole nucleus is a bioisostere of amide, ester, and carboxylic acid, and the 1,2,4-triazole ring is found in many compounds with diverse biological effects. 1,2,4-Triazole derivatives could exert their antibacterial activity through inhibition of efflux pumps, filamentous temperature-sensitive protein Z, penicillin-binding protein, DNA gyrase, and topoisomerase IV, and they play an important role in the discovery of novel antibacterial agents. Among them, 1,2,4-triazole hybrids, which have the potential to exert dual/multiple mechanisms of action, possess a promising broad-spectrum antibacterial activity against a panel of clinically important drug-resistant pathogens including MRSA. This review outlines the recent developments of 1,2,4-triazole hybrids with a potential anti-MRSA activity, covering articles published between 2010 and 2020. The mechanisms of action, critical aspects of their design, and structure-activity relationships are also discussed.

10.
Clin Rheumatol ; 40(1): 167-179, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32557257

RESUMO

OBJECTIVES: To explore the associations of FKBP4 and FKBP5 gene polymorphisms with disease susceptibility, glucocorticoid (GC) efficacy, anxiety, depression, and health-related quality of life (HRQOL) in systemic lupus erythematosus (SLE) patients. METHODS: All subjects were collected from the First and the Second Affiliated Hospital of Anhui Medical University in Hefei, China, during 2011 to 2015. In the case-control study, 541 SLE patients and 543 controls were recruited. In the follow-up study, 466 patients completed the 12-week follow-up and then were divided into GC-sensitive and GC-insensitive groups. Genotyping was determined using Multiplex SNaPshot technique. Data were analyzed using chi-square test and univariate and multivariate logistic regression analyses. RESULTS: rs4713904, rs9368878, and rs7757037 of FKBP5 were associated with depression in SLE patients (rs4713904, PBH = 0.037; rs9368878, PBH = 0.001; rs7757037, PBH = 0.003). Moreover, rs4713904 was associated with GC efficacy in males with SLE (PBH = 0.011). The rs755658 of FKBP5 was associated with improvement in social function (PBH = 0.022) and mental component summary (PBH = 0.028). The rs4713907 of FKBP5 was related to improvement in total score of SF-36, bodily pain, and mental component summary score (all PBH = 0.018). Furthermore, the rs12582595 of FKBP4 was correlated with general health improvement (PBH = 0.033). No associations were seen between FKBP4/FKBP5 gene polymorphisms and SLE susceptibility and anxiety. CONCLUSIONS: FKBP5 gene polymorphisms may be associated with depression and GC efficacy of SLE patients. Meanwhile, the genetic polymorphisms of FKBP4 and FKBP5 genes may be associated with HRQOL improvement in SLE patients. Key Points • FKBP5 gene polymorphisms were associated with depression of SLE patients. • FKBP5 gene polymorphisms were associated with GC efficacy of SLE patients. • FKBP5 gene polymorphisms were associated with HRQOL improvement in SLE patients. • FKBP4 gene polymorphisms were associated with HRQOL improvement in SLE patients.

11.
Nat Mater ; 20(1): 43-48, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32807920

RESUMO

Phonon polaritons enable light confinement at deep subwavelength scales, with potential technological applications, such as subdiffraction imaging, sensing and engineering of spontaneous emission. However, the trade-off between the degree of confinement and the excitation efficiency of phonon polaritons prevents direct observation of these modes in monolayer hexagonal boron nitride (h-BN), where they are expected to reach ultrahigh confinement. Here, we use monochromatic electron energy-loss spectroscopy (about 7.5 meV energy resolution) in a scanning transmission electron microscope to measure phonon polaritons in monolayer h-BN, directly demonstrating the existence of these modes as the phonon Reststrahlen band (RS) disappears. We find phonon polaritons in monolayer h-BN to exhibit high confinement (>487 times smaller wavelength than that of light in free space) and ultraslow group velocity down to about 10-5c. The large momentum compensation provided by electron beams additionally allows us to excite phonon polaritons over nearly the entire RS band of multilayer h-BN. These results open up a broad range of opportunities for the engineering of metasurfaces and strongly enhanced light-matter interactions.

12.
Arterioscler Thromb Vasc Biol ; : ATVBAHA120315404, 2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33356385

RESUMO

Cardiovascular disease is one of the major contributors to global disease burden. Atherosclerosis is an inflammatory process that involves the accumulation of lipids and fibrous elements in the large arteries, forming an atherosclerotic plaque. Rupture of unstable plaques leads to thrombosis that triggers life-threatening complications such as myocardial infarction. Current diagnostic methods are invasive as they require insertion of a catheter into the coronary artery. Molecular imaging techniques, such as magnetic resonance imaging, have been developed to image atherosclerotic plaques and thrombosis due to its high spatial resolution and safety. The sensitivity of magnetic resonance imaging can be improved with contrast agents, such as iron oxide nanoparticles. This review presents the most recent advances in atherosclerosis, thrombosis, and myocardial infarction molecular imaging using iron oxide-based nanoparticles. While some studies have shown their effectiveness, many are yet to undertake comprehensive testing of biocompatibility. There are still potential hazards to address and complications to diagnosis, therefore strategies for overcoming these challenges are required.

13.
Semin Thromb Hemost ; 46(8): 887-894, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33368110

RESUMO

Atrial fibrillation (AF) can be secondary to acute pulmonary embolism (PE). This study aimed to investigate the prognostic impact of new-onset AF on patients with acute PE. In this study, 4,288 consecutive patients who were diagnosed with acute PE were retrospectively screened. In total, 77 patients with acute PE and new-onset AF were analyzed. Another 154 acute PE patients without AF were selected as the age- and sex-matched control group. Adverse in-hospital outcome comprised one of the following conditions: all-cause death, endotracheal intubation, cardiopulmonary resuscitation, and intravenous catecholamine therapy. The patients with new-onset AF had higher prevalence of congestive heart failure, higher simplified PE severity index (sPESI), higher creatinine, and larger left atrium diameter. The incidences of adverse in-hospital outcomes were 10.4 and 2.6% in patients with new-onset AF and no AF, respectively (p = 0.02). Patients with sPESI ≥ 1 had higher incidence of adverse in-hospital outcomes than those with sPESI = 0 (9.4 vs. 0.9%, p < 0.01). The area under the receiver operating characteristic curve of sPESI and sPESI + AF (adding 1 point for new-onset AF) scores in assessing the adverse in-hospital outcome were 0.80 (95% confidence interval [CI]: 0.68-0.93) and 0.84 (95% CI: 0.72-0.96), respectively. In multivariable analysis, sPESI ≥ 1 (odds ratio, 8.88; 95% CI: 1.10-72.07; p = 0.04) was an independent predictor of adverse in-hospital outcome. However, new-onset AF was not an independent predictor. In the population studied, sPESI is an independent predictor of adverse in-hospital outcomes, whereas new-onset AF following acute PE is not, but it may add predictive value to sPESI.

14.
Andrologia ; : e13851, 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33368449

RESUMO

Previous studies have suggested that there is a positive correlation between prostate-specific antigen (PSA) levels and prostate volume (PV). A better understanding of the possible influence of PV on a ratio of free to total PSA (f/tPSA) may improve the diagnostic value of the prostate disease. The study group consisted of 342 men with lower urinary tract symptoms (LUTS). All patients underwent urinary tract ultrasonography and had tests carried out on PSA, serum glucose, total cholesterol, triglyceride, HDL, LDL and blood pressure. Univariate and multivariate analyses were used to assess the associations between prostate volume and f/tPSA value. We found no obvious relationship between prostate volume and f/tPSA value when PSA >10 ng/ml but did observe a positive correlation when 4 ng/ml < PSA ï¼œ 10 ng/ml (hazard ratio [HR]: 0.0012; 95% confidence interval [CI]: 0.0009-0.0248). With increasing prostate volume, multivariate analysis showed an obvious increase in f/tPSA value (HR: 0.0011; 95% CI: 0.0007-0.0015) (p ≤ .0001). We confirmed that prostate volume could affect the f/tPSA levels in serum. There was an obvious positive correlation between prostate volume and f/tPSA level when PSA levels were between 4 and 10ng/dl. There was no significant correlation between prostate volume and f/tPSA value when PSA >10 ng/ml.

15.
Zhonghua Nan Ke Xue ; 26(7): 601-604, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-33377714

RESUMO

Objective: To explore the clinical value of phosphodiesterase type-5 inhibitors (PDE-5i) combined with RigiScan-based audiovisual sexual stimulation (AVSS) test in comparison with that of nocturnal penile tumescence (NPT) test in evaluation of erectile function. METHODS: A total of 166 ED patients, aged 21-63 (mean 31) years, with a disease course of 3 months to 10 years (mean 14 months), underwent NPT test or PDE-5i + RigiScan-based AVSS test from 2017 to 2018. We compared the results of the diagnostic strategies. Normal NPT patterns were presumed to indicate psychogenic and abnormal ones to indicate organic ED. RESULTS: Compared with the results of NPT test, no statistically significant difference was observed in the accuracy rate between Viagra + AVSS test and Cialis + AVSS test (P > 0.05). PDE-5i + RigiScan-based AVSS test achieved a sensitivity of 78.9% and a specificity of 90.7% in the diagnosis of psychogenic ED and an overall accuracy rate of 81.9%. According to the results of PDE-5i + RigiScan-based AVSS test, the patients fell into a normal and an abnormal erection group, with significant differences between the two groups in age, disease course, IIEF-5 score and maintenance time of penile tip rigidity ≥60% (P < 0.05). ROC curve analysis indicated that PDE-5i + RigiScan-based AVSS test accurately manifested the erectile function of the patients. CONCLUSIONS: Compared with NPT test, PDE -5i combined with RigiScan-based AVSS test is simple, inexpensive, practical and with a high sensitivity and specificity, and therefore can be used as the first-choice strategy for etiological diagnosis of ED.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33302420

RESUMO

The Yangtze River Estuary (YRE) is the largest estuary in China. Recently, due to the increase of extent and frequency, saltwater intrusion has received more and more attention. In this paper, with the adoption of hydrodynamic and salinity transport mode, quantitative research of the influence of river discharge to the North Branch (NB) of the Yangtze River on the saltwater group migration law is conducted. Tide and salinity data are used to validate the model effectively. In different paths, the changes in flow and the movement of the saltwater group are similar. The saltwater group starts to move downward from the sixth day. In the staged downward movement, the larger the runoff volume, the further the distance of the core of the saltwater group, and converges to around 90 km gradually. At different flow rates, the relationship between the average location of each waterway saltwater group core tide cycle and time is consistent with the Gompertz model, and its parameters had a nonlinear relationship with the flow rate. A function is constructed to calculate the length and time of the saltwater group migration. As the flow rate increases, the faster the core of the saltwater group reaches the entrance. The downwards movement takes 3-8 days. Quantitative research on the influence of the saltwater spilling from NB to the three major reservoirs in the South Branch (SB)is conducted. The simulation results are consistent with the function calculation. River discharge has a direct impact on saltwater transport and diffusion in the YRE.

17.
Anal Chem ; 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33378161

RESUMO

This work developed a sensitive electrochemiluminescence (ECL) biosensor based on a cyclometalated iridium(III) complex ((bt)2Irbza), which was synthesized for the first time. Annihilation, reductive-oxidative, and oxidative-reductive ECL behaviors of (bt)2Irbza were investigated, respectively. The oxidative-reductive ECL intensity was the strongest compared with the other two, which showed 16.7 times relative ECL efficiency compared with commercial [Ru(bpy)3]2+ under the same experimental conditions. Therefore, an ECL biosensing system with (bt)2Irbza as the anodic luminophore was established for miRNA detection based on a closed bipolar electrode (BPE). Combined with both steric hindrance and catalytic effects induced by hemin/G-quadruplex in the cathodic reservoir of BPE that changed the Faraday current of the cathode and thus mediated the ECL intensity of (bt)2Irbza in the anode of BPE, the ECL sensor stated an ultrahigh sensitivity for microRNA (miRNA-122) analysis with a detection limit of 82 aM.

18.
J Hazard Mater ; 407: 124622, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33333391

RESUMO

In this work, extraction of lead from Electrolytic Manganese Anode Mud (EMAM) by microwave coupled ultrasound was studied. The results showed that microwave roasting promoted the conversion of MnO2 to Mn2O3 and Mn3O4, which greatly facilitated the subsequent leaching process of lead and the introduction of ultrasound effectively enhanced the leaching process. The leaching rate for lead from EMAM was arrived to 86.98% under the optimum conditions with the ammonium acetate concentration of 2 mol/L at 343 K and the stirring speed of 300 rpm for 60 min. With the introduction of specific power ultrasound, the leaching of lead was increased by about 10%. The microwave roasting combined with ultrasonic enhanced leaching can effectively for the reuse and reduction of EMAM which provides ideas for further investigation of lead pollution control and resource utilization in EMAM.

19.
Mol Metab ; 44: 101131, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33278637

RESUMO

BACKGROUND: Live kinase B1 (LKB1) is a tumor suppressor that is mutated in Peutz-Jeghers syndrome (PJS) and a variety of cancers. Lkb1 encodes serine-threonine kinase (STK) 11 that activates AMP-activated protein kinase (AMPK) and its 13 superfamily members, regulating multiple biological processes, such as cell polarity, cell cycle arrest, embryo development, apoptosis, and bioenergetics metabolism. Increasing evidence has highlighted that deficiency of LKB1 in cancer cells induces extensive metabolic alterations that promote tumorigenesis and development. LKB1 also participates in the maintenance of phenotypes and functions of normal cells through metabolic regulation. SCOPE OF REVIEW: Given the important role of LKB1 in metabolic regulation, we provide an overview of the association of metabolic alterations in glycolysis, aerobic oxidation, the pentose phosphate pathway (PPP), gluconeogenesis, glutamine, lipid, and serine induced by aberrant LKB1 signals in tumor progression, non-neoplastic diseases, and functions of immune cells. MAJOR CONCLUSIONS: In this review, we summarize layers of evidence demonstrating that disordered metabolisms in glucose, glutamine, lipid, and serine caused by LKB1 deficiency promote carcinogenesis and non-neoplastic diseases. The metabolic reprogramming resulting from the loss of LKB1 confers cancer cells with growth or survival advantages. Nevertheless, it also causes a metabolic frangibility for LKB1-deficient cancer cells. The metabolic regulation of LKB1 also plays a vital role in maintaining cellular phenotype in the progression of non-neoplastic diseases. In addition, lipid metabolic regulation of LKB1 plays an important role in controlling the function, activity, proliferation, and differentiation of several types of immune cells. We conclude that in-depth knowledge of metabolic pathways regulated by LKB1 is conducive to identifying therapeutic targets and developing drug combinations to treat cancers and metabolic diseases and achieve immunoregulation.

20.
Cell Biol Int ; 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325140

RESUMO

Although clinical data suggest remarkable promise for targeting programmed cell death protein-1 (PD-1) and ligand (PD-L1) signaling in non-small-cell lung cancer (NSCLC), it is still largely undetermined which subtype of patients will be responsive to checkpoint blockade. In the present study, we explored whether PD-L1 was regulated by mutant Kirsten rat sarcoma viral oncogene homolog (KRAS), which is frequently mutated in NSCLC and results in poor prognosis and low survival rates. We verified that PD-L1 levels were dramatically increased in KRAS mutant cell lines, particularly in NCI-H441 cells with KRAS G12V mutation. Overexpression of KRAS G12V remarkably elevated PD-L1 messenger RNA and protein levels, while suppression of KRAS G12V led to decreased PD-L1 levels in NCI-H441 cells. Consistently, higher levels of PD-L1 were observed in KRAS-mutated tissues as well as tumor tissues-derived CD4+ and CD8+ T cells using a tumor xenograft in B-NDG mice. Mechanically, both in vitro and in vivo assays found that KRAS G12V upregulated PD-L1 via regulating the progression of epithelial-to-mesenchymal transition (EMT). Moreover, pembrolizumab activated the antitumor activity and decreased tumor growth with KRAS G12V mutated NSCLC. This study demonstrates that KRAS G12V mutation could induce PD-L1 expression and promote immune escape via transforming growth factor-ß/EMT signaling pathway in KRAS-mutant NSCLC, providing a potential therapeutic approach for NSCLC harboring KRAS mutations.

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