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1.
ACS Synth Biol ; 13(9): 2982-2991, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39250825

RESUMO

Phenazine-based small molecules are nitrogen-containing heterocyclic compounds with diverse bioactivities and electron transfer properties that exhibit promising applications in pharmaceutical and electrochemical industries. However, the biosynthetic mechanism of highly substituted natural phenazines remains poorly understood. In this study, we report the direct cloning and heterologous expression of the lomofungin biosynthetic gene cluster (BGC) from Streptomyces lomondensis S015. Reconstruction and overexpression of the BGCs in Streptomyces coelicolor M1152 resulted in eight phenazine derivatives including two novel hybrid phenazine metabolites, and the biosynthetic pathway of lomofungin was proposed. Furthermore, gene deletion suggested that NAD(P)H-dependent oxidoreductase gene lomo14 is a nonessential gene in the biosynthesis of lomofungin. Cytotoxicity evaluation of the isolated phenazines and lomofungin was performed. Specifically, lomofungin shows substantial inhibition against two human cancer cells, HCT116 and 5637. These results provide insights into the biosynthetic mechanism of lomofungin, which will be useful for the directed biosynthesis of natural phenazine derivatives.


Assuntos
Família Multigênica , Fenazinas , Streptomyces , Fenazinas/metabolismo , Streptomyces/genética , Streptomyces/metabolismo , Humanos , Linhagem Celular Tumoral , Vias Biossintéticas/genética , Células HCT116 , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Clonagem Molecular
2.
PLoS Pathog ; 20(6): e1012260, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38885242

RESUMO

Adeno-associated virus (AAV) serotypes from primates are being developed and clinically used as vectors for human gene therapy. However, the evolutionary mechanism of AAV variants is far from being understood, except that genetic recombination plays an important role. Furthermore, little is known about the interaction between AAV and its natural hosts, human and nonhuman primates. In this study, natural AAV capsid genes were subjected to systemic evolutionary analysis with a focus on selection drives during the diversification of AAV lineages. A number of positively selected sites were identified from these AAV lineages with functional relevance implied by their localization on the AAV structures. The selection drives of the two AAV2 capsid sites were further investigated in a series of biological experiments. These observations did not support the evolution of the site 410 of the AAV2 capsid driven by selection pressure from the human CD4+ T-cell response. However, positive selection on site 548 of the AAV2 capsid was directly related to host humoral immunity because of the profound effects of mutations at this site on the immune evasion of AAV variants from human neutralizing antibodies at both the individual and population levels. Overall, this work provides a novel interpretation of the genetic diversity and evolution of AAV lineages in their natural hosts, which may contribute to their further engineering and application in human gene therapy.


Assuntos
Proteínas do Capsídeo , Dependovirus , Evolução Molecular , Seleção Genética , Dependovirus/genética , Dependovirus/imunologia , Humanos , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Variação Genética , Terapia Genética
3.
Virol J ; 21(1): 90, 2024 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654353

RESUMO

PURPOSE: To determine the correlation between HPV (human papillomavirus) 52 viral load, multiple infections and ThinPrep cytology test (TCT), to inform clinical management of HPV52-positive women after cervical cancer screening. METHODS: A total of 1,882 female patients who had positive quantitative HPV tests at Yuebei People's Hospital from January 2020 to December 2022, of whom 533 tested positive for HPV52. We excluded patients who combined HPV16 and/or HPV 18 positivity and whom HPV52 viral load could not be calculated. The final enrollment was 488 patients, including 400 NILM, 48 ASC-US, 28 LSIL and 12 HSIL. The HPV test is a quantitative multiplexed fluorescent PCR assay that provides both HPV genotyping and viral load. RESULTS: In our study, there were differences in the median distribution of viral loads among various cytological class categories. The risk of TCT results (LSIL or worse) was increased with the increase of HPV52 viral load, for every LOG unit increase in HPV52 viral load, the risk increased by 26.6%. More importantly, we found a nonlinear relationship between HPV52 viral load and TCT results (LSIL or worse) in both single and multiple infections. When the viral load reaches a threshold, the risk of abnormal cytological results increases significantly. CONCLUSION: HPV52 viral load is an independent risk factor for TCT results (LSIL or worse). The relationship between HPV52 viral load and TCT results (LSIL or worse) is not linear. Viral load may be used as a triage indicator for HPV52-positive patients, thus improving the post-screening clinical management of HPV52-positive women.


Assuntos
Papillomavirus Humano , Infecções por Papillomavirus , Neoplasias do Colo do Útero , Carga Viral , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem , Coinfecção/virologia , DNA Viral/genética , Detecção Precoce de Câncer/métodos , Genótipo , Papillomavirus Humano/classificação , Papillomavirus Humano/isolamento & purificação , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/diagnóstico , Displasia do Colo do Útero/virologia , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal
4.
MedComm (2020) ; 5(5): e539, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38680520

RESUMO

Urgent research into innovative severe acute respiratory coronavirus-2 (SARS-CoV-2) vaccines that may successfully prevent various emerging emerged variants, particularly the Omicron variant and its subvariants, is necessary. Here, we designed a chimeric adenovirus-vectored vaccine named Ad5-Beta/Delta. This vaccine was created by incorporating the receptor-binding domain from the Delta variant, which has the L452R and T478K mutations, into the complete spike protein of the Beta variant. Both intramuscular (IM) and intranasal (IN) vaccination with Ad5-Beta/Deta vaccine induced robust broad-spectrum neutralization against Omicron BA.5-included variants. IN immunization with Ad5-Beta/Delta vaccine exhibited superior mucosal immunity, manifested by higher secretory IgA antibodies and more tissue-resident memory T cells (TRM) in respiratory tract. The combination of IM and IN delivery of the Ad5-Beta/Delta vaccine was capable of synergically eliciting stronger systemic and mucosal immune responses. Furthermore, the Ad5-Beta/Delta vaccination demonstrated more effective boosting implications after two dosages of mRNA or subunit recombinant protein vaccine, indicating its capacity for utilization as a booster shot in the heterologous vaccination. These outcomes quantified Ad5-Beta/Delta vaccine as a favorable vaccine can provide protective immunity versus SARS-CoV-2 pre-Omicron variants of concern and BA.5-included Omicron subvariants.

5.
Biochem Biophys Res Commun ; 710: 149895, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38593620

RESUMO

Neurotoxicity is a common side effect of certain types of therapeutic drugs, posing a major hurdle for their clinical application. Accumulating evidence suggests that ferroptosis is involved in the neurotoxicity induced by these drugs. Therefore, targeting ferroptosis is considered to be a reasonable approach to prevent such side effect. Arctigenin (ATG) is a major bioactive ingredient of Arctium lappa L., a popular medicinal plant in Asia, and has been reported to have multiple bioactivities including neuroprotection. However, the mechanisms underlying the neuroprotection of ATG has not been well elucidated. The purpose of this study was to investigate whether the neuroprotection of ATG was associated with its ability to protect neuronal cells from ferroptosis. Using neuronal cell ferroptosis model induced by either classic ferroptosis induces or therapeutic drugs, we demonstrated for the first time that ATG in the nanomolar concentration range effectively prevented neuronal cell ferroptosis induced by classic ferroptosis inducer sulfasalazine (SAS) and erastin (Era), or therapeutic drug oxaliplatin (OXA) and 5-fluorouracil (5-FU). Mechanistically, we uncovered that the anti-ferroptotic effect of ATG was attributed to its ability to activate SLC7A11-cystine-cysteine axis. The findings of the present study implicate that ATG holds great potential to be developed as a novel agent for preventing SLC7A11 inhibition-mediated neurotoxicity.


Assuntos
Antineoplásicos , Ferroptose , Furanos , Lignanas , Síndromes Neurotóxicas , Humanos , Cisteína , Cistina , Fluoruracila , Antineoplásicos/farmacologia , Sistema y+ de Transporte de Aminoácidos
6.
MedComm (2020) ; 5(4): e511, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38525112

RESUMO

Since cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway was discovered in 2013, great progress has been made to elucidate the origin, function, and regulating mechanism of cGAS-STING signaling pathway in the past decade. Meanwhile, the triggering and transduction mechanisms have been continuously illuminated. cGAS-STING plays a key role in human diseases, particularly DNA-triggered inflammatory diseases, making it a potentially effective therapeutic target for inflammation-related diseases. Here, we aim to summarize the ancient origin of the cGAS-STING defense mechanism, as well as the triggers, transduction, and regulating mechanisms of the cGAS-STING. We will also focus on the important roles of cGAS-STING signal under pathological conditions, such as infections, cancers, autoimmune diseases, neurological diseases, and visceral inflammations, and review the progress in drug development targeting cGAS-STING signaling pathway. The main directions and potential obstacles in the regulating mechanism research and therapeutic drug development of the cGAS-STING signaling pathway for inflammatory diseases and cancers will be discussed. These research advancements expand our understanding of cGAS-STING, provide a theoretical basis for further exploration of the roles of cGAS-STING in diseases, and open up new strategies for targeting cGAS-STING as a promising therapeutic intervention in multiple diseases.

7.
Nat Aging ; 4(3): 414-433, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38321225

RESUMO

The incidence of intestinal diseases increases with age, yet the mechanisms governing gut aging and its link to diseases, such as colorectal cancer (CRC), remain elusive. In this study, while considering age, sex and proximal-distal variations, we used a multi-omics approach in non-human primates (Macaca fascicularis) to shed light on the heterogeneity of intestinal aging and identify potential regulators of gut aging. We explored the roles of several regulators, including those from tryptophan metabolism, in intestinal function and lifespan in Caenorhabditis elegans. Suggesting conservation of region specificity, tryptophan metabolism via the kynurenine and serotonin (5-HT) pathways varied between the proximal and distal colon, and, using a mouse colitis model, we observed that distal colitis was more sensitive to 5-HT treatment. Additionally, using proteomics analysis of human CRC samples, we identified links between gut aging and CRC, with high HPX levels predicting poor prognosis in older patients with CRC. Together, this work provides potential targets for preventing gut aging and associated diseases.


Assuntos
Colite , Serotonina , Animais , Humanos , Idoso , Serotonina/metabolismo , Triptofano/metabolismo , Multiômica , Colite/metabolismo , Envelhecimento/genética , Caenorhabditis elegans/metabolismo , Primatas/metabolismo
8.
Cancer Chemother Pharmacol ; 93(6): 575-585, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38383823

RESUMO

PURPOSE: 18ß-glycyrrhetinic acid (GA), the main metabolite of glycyrrhizic acid extracted from the root of licorice, has been reported to possess anti-cancer and immunomodulatory activity, but the mechanisms are not well understood. Recent studies have shown that ferroptosis of immune cells is involved in tumor-associated immune suppression. The purpose of this study was to investigate whether the enhanced immune response via inhibiting immune cell ferroptosis contributed to the anticancer effect of 18ß-GA. METHODS: Lewis Lung carcinoma mouse model and Murine CD8 + T cell culture model were used to examine the changes of immune response and ferroptosis of immune cells. RESULTS: We found that 18ß-GA was effective against lung cancer accompanied by enhanced activation of tumor-infiltrating CD8+ T cells in Lewis Lung carcinoma mouse model. Furthermore, we demonstrated that the boosted immune response by GA was attributed to its ability to inhibit arachidonic acid (AA)-mediated CD8+ T ferroptosis via suppressing CD36 expression. CONCLUSION: The findings of the present study unraveled a novel mechanism underlying the anti-cancer and immunomodulatory activity of 18ß-GA and support that 18ß-GA holds potential to be used as an immune enhancer for lung cancer prevention or treatment.


Assuntos
Linfócitos T CD8-Positivos , Carcinoma Pulmonar de Lewis , Ferroptose , Ácido Glicirretínico , Camundongos Endogâmicos C57BL , Animais , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/patologia , Ácido Glicirretínico/farmacologia , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/uso terapêutico , Ferroptose/efeitos dos fármacos , Camundongos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Linhagem Celular Tumoral
9.
Acta Radiol ; 65(1): 68-75, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37097830

RESUMO

BACKGROUND: Extramural venous invasion (EMVI) is an important prognostic factor of rectal adenocarcinoma. However, accurate preoperative assessment of EMVI remains difficult. PURPOSE: To assess EMVI preoperatively through radiomics technology, and use different algorithms combined with clinical factors to establish a variety of models in order to make the most accurate judgments before surgery. MATERIAL AND METHODS: A total of 212 patients with rectal adenocarcinoma between September 2012 and July 2019 were included and distributed to training and validation datasets. Radiomics features were extracted from pretreatment T2-weighted images. Different prediction models (clinical model, logistic regression [LR], random forest [RF], support vector machine [SVM], clinical-LR model, clinical-RF model, and clinical-SVM model) were constructed on the basis of radiomics features and clinical factors, respectively. The area under the curve (AUC) and accuracy were used to assess the predictive efficacy of different models. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated. RESULTS: The clinical-LR model exhibited the best diagnostic efficiency with an AUC of 0.962 (95% confidence interval [CI] = 0.936-0.988) and 0.865 (95% CI = 0.770-0.959), accuracy of 0.899 and 0.828, sensitivity of 0.867 and 0.818, specificity of 0.913 and 0.833, PPV of 0.813 and 0.720, and NPV of 0.940 and 0.897 for the training and validation datasets, respectively. CONCLUSION: The radiomics-based prediction model is a valuable tool in EMVI detection and can assist decision-making in clinical practice.


Assuntos
Adenocarcinoma , Neoplasias Retais , Humanos , Radiômica , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/cirurgia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/cirurgia
10.
Biomed Pharmacother ; 170: 116078, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38159375

RESUMO

PD-L1-mediated immune escape plays an important role in cancer development and progression. Targeting PD-L1 is consider to be an attractive approach for cancer treatment. PD-L1 is a heavily N-linked glycosylated protein, and the glycosylation of PD-L1 is essential for its ability to interact with its receptor PD-1 to mediate immune suppression. In the present study, we demonstrated for the first time that delta-tocotrienol (δ-T3) not any of the other forms of vitamin E was able to disrupt PD-L1 glycosylation mechanistically associated with the suppression of TCF4-STT3a/STT3b axis. The inhibition of PD-L1 glycosylation by δ-T3 resulted in the decrease of PD-L1 expression and its exosomal secretion, leading to the reduction of PD-L1 and PD-1 interaction, and reversing PD-L1-mediated immune suppression, which in turn contributed to the inhibitory effect on tumor growth. The findings of the present study provide a novel mechanistic interpretation for the superior anticancer activity of δ-T3 among 8 isomers of the vitamin E.


Assuntos
Antígeno B7-H1 , Receptor de Morte Celular Programada 1 , Linhagem Celular Tumoral , Glicosilação , Antígeno B7-H1/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Vitamina E/farmacologia
11.
Biol Trace Elem Res ; 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897593

RESUMO

Drug combination is considered to be an effective approach to improve the efficacy of cancer therapy and chemoprevention. Selenite, a representative of inorganic form of selenium, and butyrate, a major short-chain fatty acid, are two well-documented colon cancer dietary chemopreventive agents with distinct molecular mechanisms. We hypothesized that combination of selenite and butyrate might produce improved outcome against colon cancer. This hypothesis was tested using both HCT116 human colon cancer cells and its xenograft mouse model in the present study. The in vitro study showed a synergistically inhibitory effect on HCT116 colon cancer cells but not on NCM460 normal human colon mucosal epithelial cells. Consistent with the in vitro study, results of the xenograft mouse model further demonstrated that combination of selenite and butyrate led to improved efficacy in comparison with each agent alone. Mechanistically, the induction of alanine-serine-cysteine transporter 2 (ASCT2) by selenite repressed its inhibitory effect on colon cancer cells, which was reversed by its co-treatment with butyrate. The findings of the present study denote the likely potential for developing selenite/butyrate combination remedy to combat against colon cancer.

12.
Biology (Basel) ; 12(10)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37887002

RESUMO

Phenazine compounds are widely used in agricultural control and the medicine industry due to their high inhibitory activity against pathogens and antitumor activity. The green and sustainable method of synthesizing phenazine compounds through microbial fermentation often requires a complex culture medium containing tryptone and yeast extract, and its cost is relatively high, which greatly limits the large-scale industrial production of phenazine compounds by fermentation. The aim of this study was to develop a cost-effective minimal medium for the efficient synthesis of phenazine compounds by Pseudomonas chlororaphis. Through testing the minimum medium commonly used by Pseudomonas, an ME medium for P. chlororaphis with a high production of phenazine compounds was obtained. Then, the components of the ME medium and the other medium were compared and replaced to verify the beneficial promoting effect of Fe2+ and NH4+ on phenazine compounds. A cost-effective general defined medium (GDM) using glycerol as the sole carbon source was obtained by optimizing the composition of the ME medium. Using the GDM, the production of phenazine compounds by P. chlororaphis reached 1073.5 mg/L, which was 1.3 times that achieved using a complex medium, while the cost of the GDM was only 10% that of a complex medium (e.g., the KB medium). Finally, by engineering the glycerol metabolic pathway, the titer of phenazine-1-carboxylic acid reached the highest level achieved using a minimum medium so far. This work demonstrates how we systematically analyzed and optimized the composition of the medium and integrated a metabolic engineering method to obtain the most cost-effective fermentation strategy.

14.
Phytochemistry ; 215: 113841, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37660725

RESUMO

As a detoxification and metabolism organ, the liver plays a vital role in human health. However, an excessive consumption of drugs and toxins, exposure to pathogenic viruses, and unhealthy living habits can lead to liver damage, which may even develop into liver cirrhosis and liver cancer. Epimedium brevicornum Maxim. is a traditional Chinese medicine and dietary supplement in which the flavonoid icariin is a main functional component. Although the protective mechanisms of icariin and its metabolites against liver injury are not yet comprehensively understood, an increasing number of studies have confirmed their liver-protective and anticancer effects. Indeed, icaritin, one of the metabolites of icariin, is currently utilized as an active component of an anti-cancer drug. This paper presents a review of the molecular mechanisms through which icariin and its metabolites actively protect against the occurrence and development of liver injury, and, thus, provides a comprehensive reference for further research and their application in liver protection.


Assuntos
Epimedium , Extratos Vegetais , Humanos , Flavonoides/farmacologia , Fígado
15.
J Nutr Biochem ; 120: 109427, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37549833

RESUMO

Ferroptosis is an iron-dependent form of programmed cell death driven by excessive oxidation of polyunsaturated phospholipids on cellular membranes. Accumulating evidence suggests that ferroptosis has been implicated in the pathological process of various diseases, such as cardiovascular diseases, neurological diseases, liver diseases, kidney injury, lung injury, diabetes, and cancer. Targeting ferroptosis is therefore considered to be a reasonable strategy to fight against ferroptosis-associated diseases. Many dietary bioactive agents have been identified to be able to either suppress or promote ferroptosis, indicating that ferroptosis-based intervention by dietary approach may be an effective strategy for preventing and treating diseases associated with ferroptosis dysregulation. In this review, we summarize the present understanding of the functional role of ferroptosis in the pathogenesis of aforementioned diseases with an emphasis on the evidence of managing ferroptosis-related diseases with indirect dietary modulators of ferroptosis and propose issues that need to be addressed to promote practical application of dietary approach targeting ferroptosis.


Assuntos
Doenças Cardiovasculares , Ferroptose , Humanos , Apoptose , Membrana Celular , Dieta , Peroxidação de Lipídeos
16.
Altern Ther Health Med ; 29(8): 501-505, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37652426

RESUMO

Objective: This study aims to investigate the impact of 1,25(OH)2D3 on the polarization of LPS-stimulated macrophages and the underlying regulatory mechanisms. Methods: Primary macrophages were isolated and identified using immunofluorescence assays to detect macrophage biomarker expression levels. RT-PCR was employed to measure the expression of Arginase 1 (Arg-1), Interleukin-10 (IL-10), Inducible isoform of nitric oxide synthase (iNOS), and Tumor necrosis factor-α (TNF-α) in macrophages treated with various strategies. Western blotting assessed the protein expression levels of AKT1, p-AKT1, NF-κB p65, p-NF-κB p65, STAT3, and p-STAT3 in LPS-stimulated macrophages exposed to different concentrations of 1,25(OH)2D3. Results: As the LPS concentration increased from 0 to 0.5 mg/L, Arg-1, IL-10, iNOS, and TNF-α expression levels significantly increased. However, at LPS concentrations ranging from 1 mg/L to 10 mg/L, the expression of Arg-1, IL-10, iNOS, and TNF-α displayed a trend from increase to decline. The highest M2 polarization (Arg-1 and IL-10) was observed in macrophages stimulated with 0.5 mg/L LPS among the lower concentrations, while the highest M1 polarization (iNOS and TNF-α) was observed in macrophages stimulated with 5 mg/L LPS among the higher concentrations. Subsequent experiments utilized 0.5 mg/L and 5 mg/L LPS as incubation concentrations. Under LPS stimulation, iNOS was significantly upregulated, surpassing the expression level of IL-10, a marker of M2 macrophages. The introduction of 1,25(OH)2D3 facilitated M2 polarization, with 50 nM as the incubation concentration of 1,25(OH)2D3. Furthermore, 1,25(OH)2D3 reversed the elevated expression of p-AKT1, p-NF-κB p65, and p-STAT3 in macrophages stimulated with 5 mg/L LPS. Conclusions: 1,25(OH)2D3 effectively regulates the M1/M2 polarization in LPS-stimulated macrophages.


Assuntos
Interleucina-10 , Lipopolissacarídeos , Humanos , Interleucina-10/metabolismo , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Calcitriol/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Macrófagos/metabolismo
17.
Biochem Pharmacol ; 215: 115690, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37481142

RESUMO

Acquired resistance compromises the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-based therapy for non-small cell lung cancer (NSCLC), and activation of hepatocyte growth factor receptor (MET) is one of the pivotal strategies for cancer cells to acquire refractory phenotype. However, the mechanisms involved in regulating MET activity remain to be further elucidated. Using gefitinib-resistant HCC827GR cell line as a model, we unraveled that the dysregulated amino acid metabolisms reflected by elevated expression of cysteine-preferring transporter 2 (ASCT2), cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11) and asparagine synthetase (ASNS) might contribute to survival advantage of HCC827GR cells, and rendered the cells more sensitive to asparagine (ASN) deprivation compared to parental HCC827 cells. We further identified that the increased ASNS expression is a contributing factor for the activation of MET in HCC827GR cells. More importantly, we found that methylseleninic acid (MSeA), a precursor of methylselenol, effectively suppressed tumor growth in HCC827GR xenograft model, which is associated with decrease of intracellular ASN content along with inactivation of MET- T-lymphokine-activated killer cell-originated protein kinase (TOPK) signaling axis. Finally, we demonstrated that combination of MSeA and gefitinib induced a synergistic growth inhibition in HCC827GR cells. The findings of our work reveal that ASN-MET-TOPK signaling axis as a novel mechanism contributed to gefitinib-resistance and combined utilization of gefitinib and MSeA holds potential to improve the efficacy for gefitinib-resistant NSCLC.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Gefitinibe/farmacologia , Gefitinibe/uso terapêutico , Asparagina , Neoplasias Pulmonares/patologia , Receptores ErbB/metabolismo , Quinazolinas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Linhagem Celular Tumoral , Inibidores de Proteínas Quinases/farmacologia , Proliferação de Células , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
18.
Acad Radiol ; 30 Suppl 1: S185-S198, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37394412

RESUMO

RATIONALE AND OBJECTIVES: To establish a prediction model for the efficacy of neoadjuvant chemoradiotherapy (nCRT) in patients with locally advanced rectal cancer (LARC), using pretreatment magnetic resonance imaging (MRI) multisequence image features and clinical parameters. MATERIALS AND METHODS: Patients with clinicopathologically confirmed LARC were included (training and validation datasets, n = 100 and 27, respectively). Clinical data of patients were collected retrospectively. We analyzed MRI multisequence imaging features. The tumor regression grading (TRG) system proposed by Mandard et al was adopted. Grade 1-2 of TRG was a good response group, and grade 3-5 of TRG was a poor response group. In this study, a clinical model, a single sequence imaging model, and a comprehensive model combined with clinical imaging were constructed, respectively. The area under the subject operating characteristic curve (AUC) was used to evaluate the predictive efficacy of clinical, imaging, and comprehensive models. The decision curve analysis method evaluated the clinical benefit of several models, and the nomogram of efficacy prediction was constructed. RESULTS: The AUC value of the comprehensive prediction model is 0.99 in the training data set and 0.94 in the test data set, which is significantly higher than other models. Radiomic Nomo charts were developed using Rad scores obtained from the integrated image omics model, circumferential resection margin(CRM), DoTD, and carcinoembryonic antigen(CEA). Nomo charts showed good resolution. The calibrating and discriminating ability of the synthetic prediction model is better than that of the single clinical model and the single sequence clinical image omics fusion model. CONCLUSION: Nomograph, based on pretreatment MRI characteristics and clinical risk factors, has the potential to be used as a noninvasive tool to predict outcomes in patients with LARC after nCRT.


Assuntos
Segunda Neoplasia Primária , Neoplasias Retais , Humanos , Estudos Retrospectivos , Terapia Neoadjuvante/métodos , Resultado do Tratamento , Quimiorradioterapia/métodos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias Retais/patologia , Imageamento por Ressonância Magnética/métodos
19.
Cell Death Dis ; 14(5): 327, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37193711

RESUMO

Epithelial-mesenchymal transition (EMT) is associated with the invasive and metastatic phenotypes in colorectal cancer (CRC). However, the mechanisms underlying EMT in CRC are not completely understood. In this study, we find that HUNK inhibits EMT and metastasis of CRC cells via its substrate GEF-H1 in a kinase-dependent manner. Mechanistically, HUNK directly phosphorylates GEF-H1 at serine 645 (S645) site, which activates RhoA and consequently leads to a cascade of phosphorylation of LIMK-1/CFL-1, thereby stabilizing F-actin and inhibiting EMT. Clinically, the levels of both HUNK expression and phosphorylation S645 of GEH-H1 are not only downregulated in CRC tissues with metastasis compared with that without metastasis, but also positively correlated among these tissues. Our findings highlight the importance of HUNK kinase direct phosphorylation of GEF-H1 in regulation of EMT and metastasis of CRC.


Assuntos
Neoplasias Colorretais , Transição Epitelial-Mesenquimal , Humanos , Fosforilação/fisiologia , Transição Epitelial-Mesenquimal/genética , Movimento Celular/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Actinas/metabolismo , Neoplasias Colorretais/genética , Linhagem Celular Tumoral , Metástase Neoplásica , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo
20.
Phytother Res ; 37(7): 3057-3068, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36882184

RESUMO

Xanthohumol is a principal prenylated chalcone isolated from hops. Previous studies have shown that xanthohumol was effective against various types of cancer, but the mechanisms, especially the direct targets for xanthohumol to exert an anticancer effect, remain elusive. Overexpression of T-lymphokine-activated killer cell-originated protein kinase (TOPK) promotes tumorigenesis, invasion and metastasis, implying the likely potential for targeting TOPK in cancer prevention and treatment. In the present study, we found that xanthohumol significantly inhibited the cell proliferation, migration and invasion of non-small cell lung cancer (NSCLC) in vitro and suppressed tumor growth in vivo, which is well correlated with inactivating TOPK, evidenced by reduced phosphorylation of TOPK and its downstream signaling histone H3 and Akt, and decreased its kinase activity. Moreover, molecular docking and biomolecular interaction analysis showed that xanthohumol was able to directly bind to the TOPK protein, suggesting that TOPK inactivation by xanthohumol is attributed to its ability to directly interact with TOPK. The findings of the present study identified TOPK as a direct target for xanthohumol to exert its anticancer activity, revealing novel insight into the mechanisms underlying the anticancer activity of xanthohumol.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/patologia , Simulação de Acoplamento Molecular , Células Matadoras Ativadas por Linfocina/metabolismo , Células Matadoras Ativadas por Linfocina/patologia , Linhagem Celular Tumoral
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