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2.
Neurosci Lett ; 739: 135436, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33132179

RESUMO

Dry needling treatment has a promising relieving effect on Myofascial Pain Syndrome (MPS). In China, acupuncture practitioners use acupuncture needle instead to insert the "A-Shi" acupoint to treat MPS which is defined as the same as the trigger point of dry needling. This method has been applied for thousands of years in China. In this study, bupivacaine injection induced gastrocnemius muscle injury in mice. We applied the clinical improved needling method on animal model by making the angle between the skin and needle less than 30 degree. Animals got needling treatment 24 h later at the point where the bupivacaine was injected. Results of muscle H.E. staining showed that, compared to bupivacaine injection group without needling, acupuncture treatment group showed more intact muscle fibers, less inflammatory cell infiltration and fractured muscle fibers. By RNA sequencing analysis, our work firstly demonstrated that the physical stimulation of needling changed the gene expression of muscle tissue to accelerate the muscular regeneration process. Therefore, our study proved that simple needling at "A-Shi" acupoint promoted muscle regeneration and revealed underlying mechanisms of the beneficial effects of acupuncture and dry needle treatments.

3.
J Int Med Res ; 48(10): 300060520961681, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33044865

RESUMO

OBJECTIVE: This study evaluated the anti-fibrotic effects of oxymatrine and the role of endoplasmic reticulum (ER) stress in hepatic fibrosis (HF) in animal models. METHODS: The HF rat model was established by exposure to NaAsO2, followed by treatment with oxymatrine. Biomarkers of HF and ER stress were measured. The difference in protein expression between groups was evaluated using isobaric tag for relative and absolute quantification (iTRAQ) analysis. The mechanism by which oxymatrine modulated ER stress to alleviate arsenic-induced HF was evaluated using LX2 hepatic stellate cells in vitro. RESULTS: The rat model mimicked the pathological and physical phenotypes of HF including ER stress, oxidative stress, impaired liver function, and fibrosis. Treatment with oxymatrine suppressed these responses. Moreover, apoptosis, inflammation, and hepatic stellate cell activation were also inhibited by oxymatrine treatment. The differentially expressed proteins and pathways related to ER stress were identified in the HF and oxymatrine-treated groups via iTRAQ analysis combined with liquid chromatography-mass spectrometry. LX2 cells were activated by NaAsO2 in vitro. Meanwhile, oxymatrine suppressed the activation of LX2 cells by alleviating ER stress and regulating cellular calcium homeostasis. CONCLUSIONS: Oxymatrine could reverse NaAsO2-induced HF by alleviating ER stress.

4.
Med Sci Monit ; 26: e926347, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33038207

RESUMO

BACKGROUND Enhanced Recovery After Surgery (ERAS) programs can optimize clinical outcomes and have been widely used across multiple specialties, but a personalized prediction model involving ERAS for the prognosis of gastric cancer is lacking. MATERIAL AND METHODS We retrospectively collected clinical data on 725 gastric cancer patients within ERAS who underwent curative gastric resection in the Affiliated Hospital of Qingdao University from 2007 to 2014. Kaplan-Meier method, log-rank test, and Cox proportional risk model were used to determine the independent prognostic factors of patients. The accuracy of model was evaluated by C-index, calibration curve, and Decision Curve Analysis (DCA), and the receiver operator characteristic (ROC) curve was used to compare the nomogram model with the predictive value of TNM staging system. RESULTS The 5-year overall survival (OS) of 725 patients within ERAS was 72.5%. Age at diagnosis, T stage, N stage, and postoperative complications were determined to be independent factors affecting the prognosis of patients within ERAS, and nomogram model was constructed. The C-index of the training group was 0.809 and that of the verification group was 0.804; the calibration curves and DCA of the 2 groups showed good accuracy. Through verification, we found that, compared with the TNM staging assessment method, the nomogram model was more accurate in predicting the prognosis of gastric cancer. CONCLUSIONS This study identified factors affecting the prognosis of patients with gastric cancer, and we constructed the first prognostic nomogram model in ERAS mode to facilitate postoperative personalized prognostic evaluation.

5.
Cortex ; 133: 48-64, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33099075

RESUMO

Lateralization is a critical characteristic of language production and also plays a role in visual word recognition. However, the neural mechanisms underlying the interactions between visual input and spoken word representations are still unclear. We investigated the contribution of sub-lexical phonological information in visual word processing by exploiting the fact that Chinese characters can contain phonetic radicals in either the left or right half of the character. FMRI data were collected while 39 Chinese participants read words in search of target color words. On the basis of whole-brain analysis and three laterality analyses of regions of interest, we argue that visual information from centrally presented Chinese characters is split in the fovea and projected to the contralateral visual cortex, from which phonological information can be extracted rapidly if the character contains a phonetic radical. Extra activation, suggestive of more effortful processing, is observed when the phonetic radical is situated in the left half of the character and therefore initially sent to the visual cortex in the right hemisphere that is less specialized for language processing. Our results are in line with the proposal that phonological information helps written word processing by means of top-down feedback.

6.
World J Gastroenterol ; 26(37): 5646-5660, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33088158

RESUMO

BACKGROUND: At present, the enhanced recovery after surgery (ERAS) protocol is widely implemented in the field of gastric surgery. However, the effect of the ERAS protocol on the long-term prognosis of gastric cancer has not been reported. AIM: To compare the effects of ERAS and conventional protocols on short-term outcomes and long-term prognosis after laparoscopic gastrectomy. METHODS: We retrospectively analyzed the data of 1026 consecutive patients who underwent laparoscopic gastrectomy between 2012 and 2015. The patients were divided into either an ERAS group or a conventional group. The groups were matched in a 1:1 ratio using propensity scores based on covariates that affect cancer survival. The primary outcomes were the 5-year overall and cancer-specific survival rates. The secondary outcomes were the postoperative short-term outcomes and inflammatory indexes. RESULTS: The patient demographics and baseline characteristics were similar between the two groups after matching. Compared to the conventional group, the ERAS group had a significantly shorter postoperative hospital day (7.09 d vs 8.67 d, P < 0.001), shorter time to first flatus, liquid intake, and ambulation (2.50 d vs 3.40 d, P < 0.001; 1.02 d vs 3.64 d, P < 0.001; 1.47 d vs 2.99 d, P < 0.001, respectively), and lower medical costs ($7621.75 vs $7814.16, P = 0.009). There was a significantly higher rate of postoperative complications among patients in the conventional group than among those in the ERAS group (18.1 vs 12.3, P = 0.030). Regarding inflammatory indexes, the C-reactive protein and procalcitonin levels on postoperative day 3/4 were significantly different between the two groups (P < 0.001 and P = 0.025, respectively). The ERAS protocol was associated with significantly improved 5-year overall survival and cancer-specific survival rates compared with conventional protocol (P = 0.013 and 0.032, respectively). When stratified by tumour stage, only the survival of patients with stage III disease was significantly different between the two groups (P = 0.044). CONCLUSION: Adherence to the ERAS protocol improves both the short-term outcomes and the 5-year overall survival and cancer-specific survival of patients after laparoscopic gastrectomy.

7.
Immun Inflamm Dis ; 8(4): 753-762, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33124193

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2) is a single-stranded RNA virus responsible for the global pandemic of the coronavirus disease-2019 (COVID-19). To date, there are still no effective approaches for the prevention and treatment of COVID-19. OBJECTIVE: The present study aims to explore the possible mechanisms of SARS-CoV-2 infection in human lung cells. METHODS: Data interpretation was conducted by recruiting bioinformatics analysis, including Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathways analysis using downloaded data from the NCBI Gene Expression Omnibus database. RESULTS: The present study demonstrated that SARS-CoV-2 infection induces the upregulation of 14 interferon-stimulated genes, indicative of immune, and interferon responses to the virus. Notably, genes for pyrimidine metabolism and steroid hormone biosynthesis are selectively enriched in human lung cells after SARS-CoV-2 infection, suggesting that altered pyrimidine metabolism and steroid biosynthesis are remarkable, and perhaps druggable features after SARS-CoV-2 infection. Besides, there is a strong positive correlation between viral ORF1ab, ORF6, and angiotensin-converting enzyme 2 (ACE2) expression in human lung cells, implying that ACE2 facilitates SARS-CoV-2 infection and replication in host cells probably through the induction of ORF1ab and ORF6.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/etiologia , Interferons/metabolismo , Pulmão/patologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/etiologia , Betacoronavirus/metabolismo , Biologia Computacional , Infecções por Coronavirus/patologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/virologia , Perfilação da Expressão Gênica , Humanos , Pulmão/citologia , Pulmão/imunologia , Pulmão/virologia , Pandemias , Pneumonia Viral/patologia , Pirimidinas/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/virologia , Transdução de Sinais/imunologia , Esteroides/biossíntese , Regulação para Cima/imunologia , Proteínas Virais/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-33052624

RESUMO

In contrast to the wealth of asymmetric transformations for generating central chirality from alkyl radicals, the enantiocontrol over the allenyl radicals for forging axial chirality represents an uncharted domain. The challenge arises from the unique elongated linear configuration of the allenyl radicals that necessitates the stereo-differentiation of remote motifs away from the radical reaction site. We herein describe a copper-catalyzed asymmetric radical 1,4-carboalkynylation of 1,3-enynes via the coupling of allenyl radicals with terminal alkynes, providing diverse synthetically challenging tetrasubstituted chiral allenes. A chiral N,N,P-ligand is crucial for both the reaction initiation and the enantiocontrol over the highly reactive allenyl radicals. The reaction features a broad substrate scope, covering a variety of (hetero)aryl and alkyl alkynes and 1,3-enynes as well as radical precursors with excellent functional group tolerance.

9.
Cell Biol Toxicol ; 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33070227

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is an aggressive type of malignant tumor with a poor prognosis and high mortality. Aberrant activation of hedgehog signaling plays a crucial role in the maintenance and progression of PDA. Here, we report that the dietary bioflavonoid quercetin has therapeutic potential for PDA by targeting sonic hedgehog (SHH) signaling. The effects of quercetin on the proliferation, apoptosis, migration, and invasion of pancreatic cancer cells (PCCs) and tumor growth and metastasis in PDA xenograft mouse models were evaluated. Additionally, SHH signaling activity was determined. Quercetin significantly inhibited PCC proliferation by downregulating c-Myc expression. In addition, quercetin suppressed epithelial-mesenchymal transition (EMT) by reducing TGF-ß1 level, which resulted in inhibition of PCC migration and invasion. Moreover, quercetin induced PCC apoptosis through mitochondrial and death receptor pathways. In nude mouse models, PDA growth and metastasis were reduced by quercetin treatment. Mechanically, quercetin exerts its therapeutic effects on PDA by decreasing SHH activity. Interestingly, quercetin-induced SHH inactivation is mainly dependent on Gli2, but not Gli1. Enhance SHH activity by recombinant Shh protein abolished the quercetin-mediated inhibition of PCC proliferation, migration, and invasion. Furthermore, Shh activated TGF-ß1/Smad2/3 signaling and promoted EMT by inducing the expression of Zeb2 and Snail1 that eventually resulted in a partial reversal of quercetin-mediated inhibition of PCC migration and invasion. We conclude that quercetin inhibited the growth, migration, and invasion and induced apoptosis of PCCs by antagonizing SHH and TGF-ß/Smad signaling pathways. Thus, quercetin may be a potential candidate for PDA treatment.

10.
PeerJ ; 8: e10120, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083145

RESUMO

Intervertebral disc degeneration (IDD), a major cause of lower back pain, has multiple contributing factors including genetics, environment, age, and loading history. Bioinformatics analysis has been extensively used to identify diagnostic biomarkers and therapeutic targets for IDD diagnosis and treatment. However, multiple microarray dataset analysis and machine learning methods have not been integrated. In this study, we downloaded the mRNA, microRNA (miRNA), long noncoding RNA (lncRNA), and circular RNA (circRNA) expression profiles (GSE34095, GSE15227, GSE63492 GSE116726, GSE56081 and GSE67566) associated with IDD from the GEO database. Using differential expression analysis and recursive feature elimination, we extracted four optimal feature genes. We then used the support vector machine (SVM) to make a classification model with the four optimal feature genes. The ROC curve was used to evaluate the model's performance, and the expression profiles (GSE63492, GSE116726, GSE56081, and GSE67566) were used to construct a competitive endogenous RNA (ceRNA) regulatory network and explore the underlying mechanisms of the feature genes. We found that three miRNAs (hsa-miR-4728-5p, hsa-miR-5196-5p, and hsa-miR-185-5p) and three circRNAs (hsa_circRNA_100723, hsa_circRNA_104471, and hsa_circRNA_100750) were important regulators with more interactions than the other RNAs across the whole network. The expression level analysis of the three datasets revealed that BCAS4 and SCRG1 were key genes involved in IDD development. Ultimately, our study proposes a novel approach to determining reliable and effective targets in IDD diagnosis and treatment.

11.
Cell Syst ; 11(5): 509-522.e10, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33038298

RESUMO

The need to derive and culture diverse cell or tissue types in vitro has prompted investigations on how changes in culture conditions affect cell states. However, the identification of the optimal conditions (e.g., signaling molecules and growth factors) required to maintain cell types or convert between cell types remains a time-consuming task. Here, we developed EpiMogrify, an approach that leverages data from ∼100 human cell/tissue types available from ENCODE and Roadmap Epigenomics consortia to predict signaling molecules and factors that can either maintain cell identity or enhance directed differentiation (or cell conversion). EpiMogrify integrates protein-protein interaction network information with a model of the cell's epigenetic landscape based on H3K4me3 histone modifications. Using EpiMogrify-predicted factors for maintenance conditions, we were able to better potentiate the maintenance of astrocytes and cardiomyocytes in vitro. We report a significant increase in the efficiency of astrocyte and cardiomyocyte differentiation using EpiMogrify-predicted factors for conversion conditions.

12.
BMC Bioinformatics ; 21(Suppl 13): 391, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32938398

RESUMO

BACKGROUND: Resolution estimation is the main evaluation criteria for the reconstruction of macromolecular 3D structure in the field of cryoelectron microscopy (cryo-EM). At present, there are many methods to evaluate the 3D resolution for reconstructed macromolecular structures from Single Particle Analysis (SPA) in cryo-EM and subtomogram averaging (SA) in electron cryotomography (cryo-ET). As global methods, they measure the resolution of the structure as a whole, but they are inaccurate in detecting subtle local changes of reconstruction. In order to detect the subtle changes of reconstruction of SPA and SA, a few local resolution methods are proposed. The mainstream local resolution evaluation methods are based on local Fourier shell correlation (FSC), which is computationally intensive. However, the existing resolution evaluation methods are based on multi-threading implementation on a single computer with very poor scalability. RESULTS: This paper proposes a new fine-grained 3D array partition method by key-value format in Spark. Our method first converts 3D images to key-value data (K-V). Then the K-V data is used for 3D array partitioning and data exchange in parallel. So Spark-based distributed parallel computing framework can solve the above scalability problem. In this distributed computing framework, all 3D local FSC tasks are simultaneously calculated across multiple nodes in a computer cluster. Through the calculation of experimental data, 3D local resolution evaluation algorithm based on Spark fine-grained 3D array partition has a magnitude change in computing speed compared with the mainstream FSC algorithm under the condition that the accuracy remains unchanged, and has better fault tolerance and scalability. CONCLUSIONS: In this paper, we proposed a K-V format based fine-grained 3D array partition method in Spark to parallel calculating 3D FSC for getting a 3D local resolution density map. 3D local resolution density map evaluates the three-dimensional density maps reconstructed from single particle analysis and subtomogram averaging. Our proposed method can significantly increase the speed of the 3D local resolution evaluation, which is important for the efficient detection of subtle variations among reconstructed macromolecular structures.


Assuntos
Algoritmos , Microscopia Crioeletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Substâncias Macromoleculares/metabolismo
13.
Int J Mol Sci ; 21(19)2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32987693

RESUMO

Uptake transporter organic anion transporting polypeptides (OATPs), efflux transporters (P-gp, BCRP and MRP2) and cytochrome P450 enzymes (CYP450s) are widely expressed in the liver, intestine or kidney. They coordinately work to control drug disposition, termed as "interplay of transporters and enzymes". Cyclosporine A (CsA) is an inhibitor of OATPs, P-gp, MRP2, BCRP and CYP3As. Drug-drug interaction (DDI) of CsA with victim drugs occurs via disordering interplay of transporters and enzymes. We aimed to establish a whole-body physiologically-based pharmacokinetic (PBPK) model which predicts disposition of CsA and nine victim drugs including atorvastatin, cerivastatin, pravastatin, rosuvastatin, fluvastatin, simvastatin, lovastatin, repaglinide and bosentan, as well as drug-drug interactions (DDIs) of CsA with nine victim drugs to investigate the integrated effect of enzymes and transporters in liver, intestinal and kidney on drug disposition. Predictions were compared with observations. Most of the predictions were within 0.5-2.0 folds of observations. Atorvastatin was represented to investigate individual contributions of transporters and CYP3As to atorvastatin disposition and their integrated effect. The contributions to atorvastatin disposition were hepatic OATPs >> hepatic CYP3A > intestinal CYP3As ≈ efflux transporters (P-gp/BCRP/MRP2). The results got the conclusion that the developed PBPK model characterizing the interplay of enzymes and transporters was successfully applied to predict the pharmacokinetics of 10 OATP substrates and DDIs of CsA with 9 victim drugs.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32949177

RESUMO

The development of enantioconvergent cross-coupling of racemic alkyl halides directly with heteroarene C(sp2 )-H bonds has been impeded by the use of a base at elevated temperature that leads to racemization. We herein report a copper(I)/cinchona-alkaloid-derived N,N,P-ligand catalytic system that enables oxidative addition with racemic alkyl bromides under mild conditions. Thus, coupling with azole C(sp2 )-H bonds has been achieved in high enantioselectivity, affording a number of potentially useful α-chiral alkylated azoles, such as 1,3,4-oxadiazoles, oxazoles, and benzo[d]oxazoles as well as 1,3,4-triazoles, for drug discovery. Mechanistic experiments indicated facile deprotonation of an azole C(sp2 )-H bond and the involvement of alkyl radical species under the reaction conditions.

15.
Nature ; 586(7827): 101-107, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32939092

RESUMO

The reprogramming of human somatic cells to primed or naive induced pluripotent stem cells recapitulates the stages of early embryonic development1-6. The molecular mechanism that underpins these reprogramming processes remains largely unexplored, which impedes our understanding and limits rational improvements to reprogramming protocols. Here, to address these issues, we reconstruct molecular reprogramming trajectories of human dermal fibroblasts using single-cell transcriptomics. This revealed that reprogramming into primed and naive pluripotency follows diverging and distinct trajectories. Moreover, genome-wide analyses of accessible chromatin showed key changes in the regulatory elements of core pluripotency genes, and orchestrated global changes in chromatin accessibility over time. Integrated analysis of these datasets revealed a role for transcription factors associated with the trophectoderm lineage, and the existence of a subpopulation of cells that enter a trophectoderm-like state during reprogramming. Furthermore, this trophectoderm-like state could be captured, which enabled the derivation of induced trophoblast stem cells. Induced trophoblast stem cells are molecularly and functionally similar to trophoblast stem cells derived from human blastocysts or first-trimester placentas7. Our results provide a high-resolution roadmap for the transcription-factor-mediated reprogramming of human somatic cells, indicate a role for the trophectoderm-lineage-specific regulatory program during this process, and facilitate the direct reprogramming of somatic cells into induced trophoblast stem cells.

16.
Bull Environ Contam Toxicol ; 105(5): 798-805, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32909074

RESUMO

In 1963, selenosis occurred in Yutangba Village, Enshi City, China. Subsequently, local residents migrated to a new area of Yutangba to avoid high selenium (Se) exposure. In this study, 19 soil samples, 43 food samples, 60 hair samples and 58 plasma samples from local residents were randomly collected in New Yutangba Village. The mean total Se concentrations in cultivated soil samples were 1753.6 ± 742.8 µg/kg (n = 14). The estimated daily Se intake in New Yutangba Village decreased to 63.2 ± 39.8 µg/day, slightly higher than the recommended dietary Se intake for adults in China (60 µg/day). The mean Se concentrations in hair and plasma samples were 549.7 ± 165.2 µg/kg (n = 60) and 98.4 ± 32.1 µg/L (n = 58), respectively. The result indicated that appropriate activities, such as relocation, consuming a mixture of local foods and market foods containing low Se concentration, could effectively reduce the risk of high Se exposure.


Assuntos
Exposição Dietética/análise , Monitoramento Ambiental/métodos , Cabelo/química , Selênio/análise , Poluentes do Solo/análise , Solo/química , Adulto , China , Humanos , Distribuição Aleatória , Selênio/sangue , Poluentes do Solo/sangue
17.
Gastroenterology ; 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920015

RESUMO

BACKGROUND & AIMS: Streptococcus thermophilus was identified to be depleted in patients with colorectal cancer (CRC) by shotgun metagenomic sequencing of 526 multicohort fecal samples. Here, we aim to investigate whether this bacterium could act as a prophylactic for CRC prevention. METHODS: The antitumor effects of S thermophilus were assessed in cultured colonic epithelial cells and in 2 murine models of intestinal tumorigenesis. The tumor-suppressive protein produced by S thermophilus was identified by mass spectrometry and followed by ß-galactosidase activity assay. The mutant strain of S thermophilus was constructed by homologous recombination. The effect of S thermophilus on the gut microbiota composition was assessed by shotgun metagenomic sequencing. RESULTS: Oral gavage of S thermophilus significantly reduced tumor formation in both Apcmin/+ and azoxymethane-injected mice. Coincubation with S thermophilus or its conditioned medium decreased the proliferation of cultured CRC cells. ß-Galactosidase was identified as the critical protein produced by S thermophilus by mass spectrometry screening and ß-galactosidase activity assay. ß-Galactosidase secreted by S thermophilus inhibited cell proliferation, lowered colony formation, induced cell cycle arrest, and promoted apoptosis of cultured CRC cells and retarded the growth of CRC xenograft. The mutant S thermophilus without functional ß-galactosidase lost its tumor-suppressive effect. Also, S thermophilus increased the gut abundance of known probiotics, including Bifidobacterium and Lactobacillus via ß-galactosidase. ß-Galactosidase-dependent production of galactose interfered with energy homeostasis to activate oxidative phosphorylation and downregulate the Hippo pathways kinases, which partially mediated the anticancer effects of S thermophilus. CONCLUSION: S thermophilus is a novel prophylactic for CRC prevention in mice. The tumor-suppressive effect of S thermophilus is mediated at least by the secretion of ß-galactosidase.

18.
Cell Biochem Funct ; 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32749001

RESUMO

Cystine/glutamic acid reverse transporter (System Xc - ), a member of the amino acid transporter family, consists of two subunits, light chain xCT and heavy chain 4F2hc. xCT is the cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11), which promotes cystine uptake and glutathione biosynthetic, thus protecting against oxidative stress and ferroptosis. Studies have confirmed that xCT is highly expressed in a variety of tumour and is associated with tumour proliferation, invasion, metastasis, drug resistance and ferroptosis, and can be used as a potential target for tumour treatment. This review provides insights into the biological effects of xCT and contribute to the development of new xCT-based strategies.

19.
Cell Death Dis ; 11(8): 611, 2020 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792495

RESUMO

Autophagy inhibition has been demonstrated to increase the efficacy of conventional chemotherapy. In this study, we identified hederagenin, a triterpenoid derived from Hedera helix, as a potent inhibitor of autophagy and then hypothesized that hederagenin might synergize with chemotherapeutic drugs (e.g., cisplatin and paclitaxel) to kill lung cancer cells. Firstly, we observed that hederagenin induced the increased autophagosomes in lung cancer cells concomitantly with the upregulation of LC3-II and p62, which indicated the impairment of autophagic flux. The colocalization assay indicated hederagenin could not block the fusion of lysosomes and autophagosomes, whereas the lysosomal acidification might be inhibited by hederagenin as revealed by the reduced staining of acidity-sensitive reagents (i.e., Lysotracker and acridine orange). The aberrant acidic environment then impaired the function of lysosome, which was evidenced by the decrease of mature cathepsin B and cathepsin D. Lastly, hederagenin, in agree with our hypothesis, promoted pro-apoptotic effect of cisplatin and paclitaxel with the accumulation of reactive oxygen species (ROS); while the synergistic effect could be abolished by the ROS scavenger, N-acetyl-L-cysteine. These data summarily demonstrated hederagenin-induced accumulation of ROS by blocking autophagic flux potentiated the cytotoxicity of cisplatin and paclitaxel in lung cancer cells.

20.
Cell Death Dis ; 11(8): 708, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32848130

RESUMO

Cancer cells have developed chemoresistance and have improved their survival through the upregulation of autophagic mechanisms that protect mitochondrial function. Here, we report that the traditional Chinese anticancer agent tubeimoside I (Tub), which is a potent inhibitor of autophagy, can promote mitochondria-associated apoptosis in lung cancer cells. We found that Tub disrupted both mitochondrial and lysosomal pathways. One of its mechanisms was the induction of DRP1-mediated mitochondrial fragmentation. Another mechanism was the blocking of late-stage autophagic flux via impairment of lysosomal acidification through V-ATPase inhibition; this blocks the removal of dysfunctional mitochondria and results in reactive oxygen species (ROS) accumulation. Excessive ROS accumulation causes damage to lysosomal membranes and increases lysosomal membrane permeability, which leads to the leakage of cathepsin B. Finally, cathepsin B upregulates Bax-mediated mitochondrial outer membrane permeability and, subsequently, cytosolic cytochrome C-mediated caspase-dependent apoptosis. Thus, the cancer cell killing effect of Tub is enhanced through the formation of a positive feedback loop. The killing effect of Tub on lung cancer cells was verified in xenografted mice. In summary, Tub exerts a dual anticancer effect that involves the disruption of mitochondrial and lysosomal pathways and their interaction and, thereby, has a specific and enhanced killing effect on lung cancer cells.

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