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1.
Adv Mater ; : e2312153, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38444205

RESUMO

The presence of bacteria in tumor results in chemotherapeutic drug resistance and weakens the immune response in colorectal cancer. To overcome bacterium-induced chemotherapeutic drug resistance and potentiate antitumor immunity, herein a novel molecule Biotin-Lys(SA-Cip-OH)-Lys(SA-CPT)-Phe-Phe-Nap (Biotin-Cip-CPT-Nap) is rationally designed containing four functional motifs (i.e., a biotin motif for targeting, Phe-Phe(-Nap) motif for self-assembly, ciprofloxacin derivative (Cip-OH) motif for antibacterial effect, and camptothecin (CPT) motif for chemotherapy). Using the designed molecule, a novel strategy of intracellular enzymatic nanofiber formation and synergistic antibacterium-enhanced chemotherapy and immunotherapy is achieved. Under endocytosis mediated by highly expressed biotin receptor in colorectal cancer cell membrane and the catalysis of highly expressed carboxylesterase in the cytoplasm, this novel molecule can be transformed into Biotin-Nap, which self-assembled into nanofibers. Meanwhile, antibiotic Cip-OH and chemotherapeutic drug CPT are released, overcoming bacterium-induced drug resistance and enhancing the therapeutic efficacy of immunotherapy towards colorectal cancer. This work offers a feasible strategy for the design of novel multifunctional prodrugs to improve the efficiency of colorectal cancer treatment.

2.
Adv Healthc Mater ; 13(10): e2303472, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37985951

RESUMO

Current molecular photoacoustic (PA) probes are designed with either stimulus-turned "on" or assembly-enhanced signals to trace biological analytes/events. PA probes based on the nature-derived click reaction between 2-cyano-6-aminobenzothiazole (CBT) and cysteine (Cys) (i.e., CBT-Cys click reaction) possess both "turn-on" and "enhanced" PA signals; and thus, should have higher sensitivity. Nevertheless, such PA probes, particularly those for sensitive imaging of tumor hypoxia, remain scarce. Herein, a PA probe NI-Cys(StBu)-Dap(IR780)-CBT (NI-C-CBT) is rationally designed, which after being internalized by hypoxic tumor cells, is cleaved by nitroreductase under the reduction condition to yield cyclic dimer C-CBT-Dimer to turn the PA signal "ON" and subsequently assembled into nanoparticles C-CBT-NPs with additionally enhanced PA signal ("Enhanced"). NI-C-CBT exhibits 1.7-fold "ON" and 3.2-fold overall "Enhanced" PA signals in vitro. Moreover, it provides 1.9-fold and 2.8-fold overall enhanced PA signals for tumor hypoxia imaging in HeLa cells and HeLa tumor-bearing mice, respectively. This strategy is expected to be widely applied to design more "smart" PA probes for sensitive imaging of important biological events in vivo in near future.


Assuntos
Nanopartículas , Técnicas Fotoacústicas , Humanos , Animais , Camundongos , Células HeLa , Hipóxia Tumoral , Diagnóstico por Imagem , Nitrorredutases , Técnicas Fotoacústicas/métodos
3.
Anal Chem ; 95(39): 14511-14515, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37721425

RESUMO

Photoacoustic (PA) imaging of urokinase-type plasminogen activator (uPA) activity in vivo holds high promise for early diagnosis of breast cancer. Molecular probes with resisted fluorescence (FL) emission for enhanced PA signals of uPA activity have not been reported. Herein, we proposed a molecular probe Cbz-Gly-Gly-Arg-Phe-Phe-IR775 (Z-GGRFF-IR775) which, upon uPA cleavage, assembled into nanoparticles FF-IR775-NP with quenched fluorescence but enhanced PA signals. Experimental results validated that, upon uPA activation, Z-GGRFF-IR775 exhibited 4.7-fold, 4.1-fold, and 2.9-fold higher PA signals over those in uPA inhibitor-treated control groups in vitro, in MDA-MB-231 cells, and in a tumor-bearing mouse model, respectively. We anticipate that this probe could be applied for highly sensitive PA imaging of uPA activity in early stage malignant tumors in the near future.


Assuntos
Neoplasias , Técnicas Fotoacústicas , Animais , Camundongos , Ativador de Plasminogênio Tipo Uroquinase , Diagnóstico por Imagem , Receptores de Ativador de Plasminogênio Tipo Uroquinase
4.
Adv Healthc Mater ; 12(18): e2203283, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36880480

RESUMO

Staphylococcus aureus (S. aureus) remains a leading cause of bacterial infections. However, eradication of S. aureus infections with common antibiotics is increasingly difficult due to outbreaks of drug resistance. Therefore, new antibiotic classes and antibacterial strategies are urgently in demand. Herein, it is shown that an adamantane-peptide conjugate, upon dephosphorylation by alkaline phosphatase (ALP) constitutively expressed on S. aureus, generates fibrous assemblies in situ to combat S. aureus infection. By attaching adamantane to a phosphorylated tetrapeptide Nap-Phe-Phe-Lys-Tyr(H2 PO3 )-OH, the rationally designed adamantane-peptide conjugate Nap-Phe-Phe-Lys(Ada)-Tyr(H2 PO3 )-OH (Nap-FYp-Ada) is obtained. Upon bacterial ALP activation, Nap-FYp-Ada is dephosphorylated and self-assembles into nanofibers on the surface of S. aureus. As revealed by cell assays, the assemblies of adamantane-peptide conjugates interact with cell lipid membrane and thereby disrupt membrane integrity to kill S. aureus. Animal experiments further demonstrate the excellent potential of Nap-FYp-Ada in the treatment of S. aureus infection in vivo. This work provides an alternative approach to design antimicrobial agents.


Assuntos
Anti-Infecciosos , Infecções Estafilocócicas , Animais , Staphylococcus aureus/metabolismo , Peptídeos/farmacologia , Infecções Estafilocócicas/tratamento farmacológico , Antibacterianos/farmacologia , Fosfatase Alcalina/metabolismo , Testes de Sensibilidade Microbiana
5.
Adv Healthc Mater ; 11(23): e2201916, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36148589

RESUMO

Chemotherapy has remained an effective and predominant cancer treatment for the past decades, but is hampered by its low response rate and severe systemic toxicity. Combination chemotherapies are proposed to address these issues, yet their therapeutic outcomes are still far from satisfactory. Thus, it is urgent to develop novel strategies to promote tumor chemosensitivity while reducing toxic side effects of chemotherapeutics. Herein, employing a rationally designed peptide conjugate Nap-Phe-Phe-Lys(SA-AZD8055)-Tyr(H2 PO3 )-OH (Nap-AZD-Yp), a novel approach of simultaneous intracellular nanofiber formation and autophagy inducer release is proposed for selectively sensitizing tumor to chemotherapy. Upon sequential catalyses of alkaline phosphatase and carboxylesterase, Nap-AZD-Yp undergoes nanosphere-to-nanofiber transition accompanied by autophagy inducer AZD8055 release in cancer cells. Cell experiments show enhanced endocytosis of anticancer drug doxorubicin and inhibition of cell migration due to the intracellular nanofiber formation. The released AZD8055 further activates excessive autophagy of cancer cells, sensitizing them to chemotherapy. Animal experiment results suggest Nap-AZD-Yp can significantly enhance the therapeutic effects of doxorubicin on tumors while mitigate its toxic adverse effects on normal tissues. It is anticipated that the "smart" concept in this work c be widely employed to develop novel combinational therapies for the treatment of cancers and other diseases in near future.


Assuntos
Autofagia , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Doxorrubicina/farmacologia
6.
Int Immunopharmacol ; 100: 108067, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34481142

RESUMO

Acute pancreatitis (AP) is an inflammatory disease of the pancreas. Accumulating studies have revealed the involvement of tumor necrosis factor alpha-induced protein 3 (TNFAIP3) in the progression of AP. Here, the current study was conducted to elucidate the role of TNFAIP3 and the underlying molecular mechanisms on the progression of AP. The in vivo animal model and in vitro cell model of AP were generated by retrograde injection of sodium taurocholate and stimulation of cerulein into AR42J cells, respectively. Relationships among TNFAIP3, receptor interacting protein 3 (RIP3) and nod-like receptor protein 3 (NLRP3) were predicted on bioinformatics websites and verified by co-immunoprecipitation. AR42J cells were transfected with overexpressing plasmid or shRNA to study the effects of TNFAIP3/RIP3/NLRP3 axis on cell proliferation and apoptosis, secretion of inflammatory cytokines and production of ROS. The effect of TNFAIP3/RIP3/NLRP3 axis in AP was further confirmed in vivo. High expression of TNFAIP3 was observed in AP pancreatic tissues and AP cell model. TNFAIP3 increased RIP phosphorylation through deubiquitination. RIP activated the NLRP3 inflammasome. Silencing of TNFAIP3 or RIP3T led to elevated proliferation and inhibited apoptosis in AR42J cells, accompanied by decreased inflammatory cytokine levels and ROS production. The protective role of inhibited TNFAIP3 in AP was confirmed evidenced by reduced levels of AMY, LIPA, and ROS in vivo. Collectively, overexpressed TNFAIP3 could contribute to the progression of AP by activating RIP3/NLRP3 axis, providing a potential therapeutic target for AP treatment.


Assuntos
Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pancreatite/imunologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , Inflamassomos/imunologia , Inflamassomos/metabolismo , Masculino , Pâncreas/imunologia , Pâncreas/patologia , Pancreatite/induzido quimicamente , Pancreatite/patologia , Fosforilação/imunologia , Ratos , Ácido Taurocólico/administração & dosagem , Ácido Taurocólico/toxicidade , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Ubiquitinação/imunologia
7.
ACS Nano ; 15(5): 8039-8068, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33974797

RESUMO

Cancer cells frequently exhibit resistance to various molecular and nanoscale drugs, which inevitably affects the drugs' therapeutic outcomes. Overexpression of glutathione (GSH) has been observed in many cancer cells, and solid evidence has corroborated the resulting tumor resistance to a variety of anticancer therapies, suggesting that this biochemical characteristic of cancer cells can be developed as a potential target for cancer treatments. The single treatment of GSH-depleting agents can potentiate the responses of the cancer cells to different cell death stimuli; therefore, as an adjunctive strategy, GSH depletion is usually combined with mainstream cancer therapies for enhancing the therapeutic outcomes. Propelled by the rapid development of nanotechnology, GSH-depleting agents can be readily constructed into anticancer nanomedicines, which have shown a steep rise over the past decade. Here, we review the common GSH-depleting nanomedicines which have been widely applied in synergistic cancer treatments in recent years. Some current challenges and future perspectives for GSH depletion-based cancer therapies are also presented. With the understanding of the structure-property relationship and action mechanisms of these biomaterials, we hope that the GSH-depleting nanotechnology will be further developed to realize more effective disease treatments and even achieve successful clinical translations.


Assuntos
Glutationa , Neoplasias , Morte Celular , Humanos , Nanomedicina , Neoplasias/tratamento farmacológico
8.
Cell Death Dis ; 11(9): 768, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943616

RESUMO

Lung cancer is the leading cause of cancer-associated mortality worldwide. DNA damage-regulated autophagy modulator 1 (DRAM1) plays an important roles in autophagy and tumor progression. However, the mechanisms by which DRAM1 inhibits tumor growth are not fully understood. Here, we report that DRAM1 was decreased in nonsmall-cell lung carcinoma (NSCLC) and was associated with poor prognosis. We confirmed that DRAM1 inhibited the growth, migration, and invasion of NSCLC cells in vitro. Furthermore, overexpression of DRAM1 suppressed xenografted NSCLC tumors in vivo. DRAM1 increased EGFR endocytosis and lysosomal degradation, downregulating EGFR signaling pathway. On one side, DRAM1 interacted with EPS15 to promote EGFR endocytosis, as evidence by the results of proximity labeling followed by proteomics; on the other, DRAM1 recruited V-ATP6V1 subunit to lysosomes, thereby increasing the assemble of the V-ATPase complex, resulting in decreased lysosomal pH and increased activation of lysosomal proteases. These two actions of DRAM1 results in acceleration of EGFR degradation. In summary, these in vitro and in vivo studies uncover a novel mechanism through which DRAM1 suppresses oncogenic properties of NSCLC by regulating EGFR trafficking and degradation and highlights the potential value of DRAM1 as a prognostic biomarker in lung cancers.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , Células A549 , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Biologia Computacional , Dano ao DNA , Endocitose , Receptores ErbB/metabolismo , Células HEK293 , Humanos , Concentração de Íons de Hidrogênio , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Transplante de Neoplasias , Prognóstico
9.
Fish Shellfish Immunol ; 105: 233-243, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32629104

RESUMO

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a crucial adapter protein in the toll-like receptor signaling pathway that triggers downstream molecules involved in innate immunity. Although TRAF6 has been well studied in mammals, the molecular information and function of TRAF6 in fish is still limited. Here, we identified and analyzed a TRAF6 homolog (LmTRAF6) from the spotted sea bass (Lateolabrax maculatus). Similar to its counterparts in mammals and other fish species, LmTRAF6 shares the domain topology containing one N-terminal RING, two TRAF-type zinc fingers, a coiled-coil region and a C-terminal MATH domain. Despite a sequence similarity of 60% with mammalian TRAF6s, LmTRAF6 shares higher similarities with teleost homologs (~68%-93%). The coding region of LmTRAF6 gene contains seven exons and six introns, which is consistent to the genetic organization in grouper and rock bream, but not in zebrafish, common carp and tetrapods (the sixth intron was lost resulting in a combined exon). Quantitative real-time polymerase chain reaction analysis revealed that LmTRAF6 transcripts were ubiquitously expressed in all tested tissues and upregulated after Vibrio. harveyi and S. agalactiae infection. LmTRAF6 could assist HEK293T cells to survive by inhibiting apoptosis under both V. harveyi and S. agalactiae stimulation. Intracellular localization showed that LmTRAF6 was localized mainly in the cytoplasm. Overexpression of wild-type (WT) LmTRAF6 and the truncated form of △MATH increased the ability of NF-κB in HEK293T cells, whereas truncations, including the △RING and △coiled-coil domain, did not significantly activate NF-κB, indicating that the RING finger and coiled-coil domain play crucial roles in downstream signal transduction. In addition, overexpression of LmTRAF6-WT significantly increased the activation of NF-κB in HEK293T cells under V. harveyi and S. agalactiae stimulation. These results suggest that LmTRAF6 activates NF-κB and plays a potential role in the immune defense system against bacterial infection.


Assuntos
Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Perciformes/genética , Perciformes/imunologia , Fator 6 Associado a Receptor de TNF/genética , Fator 6 Associado a Receptor de TNF/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Alinhamento de Sequência/veterinária , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , Fator 6 Associado a Receptor de TNF/química , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
10.
Adv Exp Med Biol ; 1206: 109-126, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31776982

RESUMO

Beclin 1 is the first mammalian autophagy protein identified as a novel Bcl-2-interacting protein. Subsequent studies have demonstrated that this landmark protein is essential for autophagy. By investigating the interaction between Bcl-2 and Beclin 1, key molecular mechanisms of mammalian autophagy regulation have been discovered. In this chapter, we will first review the discovery of Beclin 1 and then focus on the mechanisms of Bcl-2 and Beclin 1 regulation and their effect on autophagy regulation. Finally, we summarize the evidence related to the interaction of Bcl-2 and Beclin 1 and the involvement of these proteins in human diseases such as cancers, neurodegenerative diseases and infectious diseases.


Assuntos
Autofagia , Proteína Beclina-1 , Proteínas Proto-Oncogênicas c-bcl-2 , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/genética , Proteína Beclina-1/metabolismo , Regulação da Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-31276813

RESUMO

Lactate dehydrogenase (LDH) is a key enzyme involved in anaerobic metabolism in most organisms. In the present study, we determined the structure and function of LDH sequence in Scylla paramamosain (SpLDH) by gene cloning, expression and RNA interference techniques in order to explore the genetic characteristics of LDH and its relationship with HIF-1 during hypoxia. The full-length cDNA was 1453 bp with an open reading frame (ORF) of 996 bp, and encoded a polypeptide of 332 amino acids. Homology analysis showed that the SpLDH gene is highly similar to arthropods. The SpLDH transcript increased after hypoxia in all tested tissues. The silencing of HIF-1 blocked the increase in LDH mRNA and activity, which were induced by hypoxia in gill and muscle tissues. Our results indicated that SpLDH expression was regulated transcriptionally by HIF-1.


Assuntos
Proteínas de Artrópodes , Braquiúros , Hipóxia/metabolismo , L-Lactato Desidrogenase , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/classificação , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/fisiologia , Braquiúros/enzimologia , Braquiúros/genética , Clonagem Molecular , DNA Complementar , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , L-Lactato Desidrogenase/classificação , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/fisiologia , Fases de Leitura Aberta , Filogenia , Alinhamento de Sequência
12.
Cell Commun Signal ; 17(1): 28, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30902093

RESUMO

BACKGROUND: Macroautophagy (hereafter autophagy) is a tightly regulated process that delivers cellular components to lysosomes for degradation. Damage-regulated autophagy modulator 1 (DRAM1) induces autophagy and is necessary for p53-mediated apoptosis. However, the signalling pathways regulated by DRAM1 are not fully understood. METHODS: HEK293T cells were transfected with FLAG-DRAM1 plasmid. Autophagic proteins (LC3 and p62), phosphorylated p53 and the phosphorylated proteins of the class I PI3K-Akt-mTOR-ribosomal protein S6 (rpS6) signalling pathway were detected with Western blot analysis. Cellular distribution of DRAM1 was determined with immunostaining. DRAM1 was knocked down in HEK293T cells using siRNA oligos which is confirmed by quantitative RT-PCR. Cells were serum starved for 18 h after overexpression or knockdown of DRAM1 to decrease the rpS6 activity to the basal level, and then the cells were stimulated with insulin growth factor, epidermal growth factor or serum. rpS6 phosphorylation and rpS6 were detected with Western blotting. Similarly, after overexpression or knockdown of DRAM1, phosphorylation of IGF-1Rß and IGF-1R were examined with Western blotting. Cell viability was determined with CCK-8 assay and colony formation assay. Finally, human cancer cells Hela, SW480, and HCT116 were transfected with the FLAG-DRAM1 plasmid and phosphorylated rpS6 and rpS6 were detected with Western blot analysis. RESULTS: DRAM1 induced autophagy and inhibited rpS6 phosphorylation in an mTORC1-dependent manner in HEK293T cells. DRAM1 didn't affect the phosphorylated and total levels of p53. Furthermore, DRAM1 inhibited the activation of the PI3K-Akt pathway stimulated with growth factors or serum. DRAM1 was localized at the plasma membrane and regulate the phosphorylation of IGF-1 receptor. DRAM1 decreased cell viability and colony numbers upon serum starvation. Additionally, DRAM1 inhibited rpS6 phosphorylation in several human cancer cells. CONCLUSIONS: Here we provided evidence that DRAM1 inhibited rpS6 phosphorylation in multiple cell types. DRAM1 inhibited the phosphorylation of Akt and the activation of Akt-rpS6 pathway stimulated with growth factors and serum. Furthermore, DRAM1 regulated the activation of IGF-1 receptor. Thus, our results identify that the class I PI3K-Akt-rpS6 pathway is regulated by DRAM1 and may provide new insight into the potential role of DRAM1 in human cancers.


Assuntos
Autofagia/fisiologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas de Membrana , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo , Proteína S6 Ribossômica/metabolismo , Apoptose , Proliferação de Células , Sobrevivência Celular , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana/fisiologia , Fosforilação , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
13.
Neurobiol Dis ; 122: 41-48, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29800676

RESUMO

Protein homeostasis or proteostasis is critical for proper cellular function and survival. It relies on the balance between protein synthesis and degradation. Lysosomes play an important role in degrading and recycling intracellular components via autophagy. Among the three types of lysosome-based autophagy pathways, chaperone-mediated autophagy (CMA) selectively degrades cellular proteins with KFERQ-like motif by unique machinery. During the past several years, significant advances have been made in our understanding of how CMA itself is modulated and what physiological and pathological processes it may be involved in. One particularly exciting discovery is how other cellular stress organelles such as ER signal to CMA. As more proteins are identified as CMA substrates, CMA function has been associated with an increasing number of important cellular processes, organelles, and diseases, including neurodegenerative diseases. Here we will summarize the recent advances in CMA biology, highlight ER stress-induced CMA, and discuss the role of CMA in diseases.


Assuntos
Autofagia/fisiologia , Chaperonas Moleculares/metabolismo , Animais , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo
14.
Curr Pharmacol Rep ; 4(3): 261-275, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34540559

RESUMO

PURPOSE OF THE REVIEW: To reason that targeting chaperone-mediated autophagy (CMA) represents a promising approach for disease therapy, we will summarize advances in researches on the relationship between CMA and diseases and discuss relevant strategies for disease therapy by targeting the CMA process. RECENT FINDINGS: CMA is a unique kind of selective autophagy in lysosomes. Under physiological conditions, CMA participates in the maintenance of cellular homeostasis by protein quality control, bioenergetics, and timely regulated specific substrate-associated cellular processes. Under pathological conditions, CMA interplays with various disease conditions. CMA makes adaptive machinery to address stress, while disease-associated proteins alter CMA which is involved in pathogeneses of diseases. As more proteins are identified as CMA substrates and regulators, dysregulation of CMA has been implicated in an increasing number of diseases, while rectifying CMA alteration may be a benefit for these diseases. SUMMARY: Alterations of CMA in diseases mainly including neurodegenerative diseases and many cancers raise the possibility of targeting CMA to recover cellular homeostasis as one potential strategy for therapy of relevant diseases.

15.
Tumori ; 104(3): 188-195, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28362059

RESUMO

OBJECTIVE: To explore the predictive value of diffusion-weighted imaging (DWI) in evaluating the short-term efficacy of concurrent chemoradiotherapy (CCRT) in the treatment of patients with non-small cell lung cancer (NSCLC). METHODS: A total of 192 patients with NSCLC were selected and treated with CCRT. Dynamic contrast-enhanced magnetic resonance imaging combined with DWI was performed on all patients before and after CCRT treatment. Correspondingly, apparent diffusion coefficient (ADC) values were recorded before treatment (ADCpre), during treatment (ADCmid), and after treatment (ADCpost). Tumor response was evaluated as complete response (CR), partial response (PR), stable disease (SD), or progressive disease (PD). Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic power of quantitative DWI parameters in predicting the short-term efficacy of CCRT for patients with NSCLC. RESULTS: There were 21 patients with CR, 82 with PR, 77 with SD, and 12 with PD. The ADCpre was negatively correlated with tumor regression rate, whereas ADCmid, ADCpost, and their respective change rates ∆ADCmid and ∆ADCpost were positively related to tumor regression rate. The ROC curve analysis suggested ADCpre = 1.38 × 10-3 mm2/s, ∆ADCmid = 14.14%, and ∆ADCpost = 20.39% as thresholds to predict the short-term efficacy of CCRT, with corresponding areas under the curve of 0.637, 0.743, and 0.752, respectively. CONCLUSIONS: These findings indicate that DWI provides promising predictive value in evaluating the short-term efficacy of CCRT in the treatment of patients with NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Resultado do Tratamento
16.
Int J Biol Sci ; 13(9): 1192-1202, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29104510

RESUMO

Background: To compare the risk of type 2 diabetes (T2DM) between patients with and without chronic osteomyelitis (COM), both in humans and in mice, and to explore risk factors in COM patients who developed T2DM. Methods: One hundred seven patients with COM and 114 patients without COM were consecutively enrolled and retrospectively analysed. Clinical data concerning the time to develop diabetes, glucose metabolism, lipid metabolism, inflammatory factors, mental health and frequency of specialist visits were collected. A mouse model of osteomyelitis was used to verify the presence of impaired glucose metabolism and depression. All data were processed by SPSS. Results: The incidence of T2DM was 2.37-fold higher in patients with COM than in those without. In COM patients, subjects with T2DM (DDM) had higher BMI, less exercise and more frequent visits to specialists than those without (Con). Glucose and lipid metabolism were worse in patients with DDM. Patients with DDM had higher levels of white blood cells (12.9±2.1×109/L vs. 11.7±2.2×109/L, p=0.027), CRP (28.4±4.5 mg/L vs. 22.0±4.8 mg/L, p<0.001), TNF-α (13.5±5.0 pg/mL vs. 9.4±2.6 pg/mL, p= 0.003) and IL-6 (12.9±3.2 pg/mL vs. 9.2±2.7 pg/mL, p<0.001). Significantly increased fasting blood glucose concentrations and impairment of oral glucose tolerance tests were also observed in mice modelling osteomyelitis, which were accompanied by elevated TNF-α and IL-6 levels. Furthermore, the proportion of depression (63.2% vs. 35.2%, p=0.003) and severe anxiety (31.6% vs. 9.1%, p=0.002) were significantly higher in the DDM group. Osteomyelitis mice showed obvious depressive-like behaviours. The levels of TNF-α, IL-6, CRP, BMI, and LDL; lack of exercise; SAS; HAQ; and SF36 assessment were risk factors for the development of T2DM in COM patients. Conclusions: Chronic osteomyelitis increased the incidence of T2DM in both humans and mice. Inflammation, mental illness and lack of exercise were risk factors for the occurrence of T2DM in osteomyelitis. Comprehensive consideration of patient history, including metabolism and mental health, is needed in planning future treatment.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Osteomielite/metabolismo , Animais , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/genética , Humanos , Resistência à Insulina/genética , Resistência à Insulina/fisiologia , Interleucina-6/metabolismo , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , Camundongos , Osteomielite/genética , Fatores de Risco
17.
DNA Cell Biol ; 36(9): 775-780, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28777670

RESUMO

Osteosarcoma (OS) is a bone malignancy with high incidence. The underlying molecular mechanisms that are associated with the development of OS need further investigation. In this study, we showed that SLC34A2, a member of the solute carrier gene family, was significantly downregulated in OS patients and cell lines. Overexpression of SLC34A2 inhibited the proliferation, migration, and invasion of OS cells. Mechanistically, we found that SLC34A2 interacted with PTEN, and inactivated the PI3K/AKT signaling pathway. Collectively, our results demonstrated that SLC34A2 plays important roles in regulating the cancer cell growth of OS. The downregulation of SLC34A2 in OS patients suggested that it might be a promising target in the diagnosis and therapy of OS.


Assuntos
Neoplasias Ósseas/patologia , Osteossarcoma/patologia , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Antiportadores de Cloreto-Bicarbonato/genética , Antiportadores de Cloreto-Bicarbonato/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Osteossarcoma/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo
18.
Acta Pharmacol Sin ; 38(9): 1305-1316, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28603284

RESUMO

Transcription factor EB (TFEB) is a master regulator of autophagy activity and lysosomal biogenesis, but its role in autophagy-mediated cell survival and chemotherapy resistance is not completely understood. In this study, we explored whether TFEB played an important role in autophagy-mediated chemotherapy resistance in human cancer LoVo and HeLa cells in vitro. Treatment of human colon cancer LoVo cells with doxorubicin (0.5 µmol/L) induced autophagy activation and nuclear translocation of TFEB, which resulted from inactivation of the mTOR pathway. In both LoVo and HeLa cells, overexpression of TFEB enhanced doxorubicin-induced autophagy activation and significantly decreased doxorubicin-induced cell death, whereas knockdown of TFEB with small interfering RNA blocked doxorubicin-induced autophagy and significantly enhanced the cytotoxicity of doxorubicin. In LoVo cells, autophagy inhibition by 3-methyladenine (3-MA) or knockdown of autophagy-related gene Atg5 increased cell death in response to doxorubicin, and abolished TFEB overexpression-induced chemotherapy resistance, suggesting that the inhibition of autophagy made cancer cells more sensitive to doxorubicin. The results demonstrate that TFEB-mediated autophagy activation decreases the sensitivity of cancer cells to doxorubicin.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Antibióticos Antineoplásicos/química , Apoptose/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/análise , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
Biomed Res Int ; 2017: 5390839, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28164124

RESUMO

Hemorrhagic stroke can occur after spine and joint surgeries such as laminectomy, lumbar spinal fusion, tumor resection, and total joint arthroplasty. Although this kind of stroke rarely happens, it may cause severe consequences and high mortality rates. Typical clinical symptoms of hemorrhagic stroke after spine and joint surgeries include headache, vomiting, consciousness disturbance, and mental disorders. It can happen several hours after surgeries. Most bleeding sites are located in cerebellar hemisphere and temporal lobe. A cerebrospinal fluid (CSF) leakage caused by surgeries may be the key to intracranial hemorrhages happening. Early diagnosis and treatments are very important for patients to prevent the further progression of intracranial hemorrhages. Several patients need a hematoma evacuation and their prognosis is not optimistic.


Assuntos
Hemorragias Intracranianas/complicações , Articulações/cirurgia , Procedimentos Ortopédicos/efeitos adversos , Coluna Vertebral/cirurgia , Acidente Vascular Cerebral/complicações , Humanos , Fatores de Risco , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/terapia
20.
Mol Cell ; 64(5): 859-874, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27867011

RESUMO

Mitochondrial acetyl-CoA acetyltransferase 1 (ACAT1) regulates pyruvate dehydrogenase complex (PDC) by acetylating pyruvate dehydrogenase (PDH) and PDH phosphatase. How ACAT1 is "hijacked" to contribute to the Warburg effect in human cancer remains unclear. We found that active, tetrameric ACAT1 is commonly upregulated in cells stimulated by EGF and in diverse human cancer cells, where ACAT1 tetramers, but not monomers, are phosphorylated and stabilized by enhanced Y407 phosphorylation. Moreover, we identified arecoline hydrobromide (AH) as a covalent ACAT1 inhibitor that binds to and disrupts only ACAT1 tetramers. The resultant AH-bound ACAT1 monomers cannot reform tetramers. Inhibition of tetrameric ACAT1 by abolishing Y407 phosphorylation or AH treatment results in decreased ACAT1 activity, leading to increased PDC flux and oxidative phosphorylation with attenuated cancer cell proliferation and tumor growth. These findings provide a mechanistic understanding of how oncogenic events signal through distinct acetyltransferases to regulate cancer metabolism and suggest ACAT1 as an anti-cancer target.


Assuntos
Acetil-CoA C-Acetiltransferase/metabolismo , Mitocôndrias/enzimologia , Complexo Piruvato Desidrogenase/metabolismo , Acetil-CoA C-Acetiltransferase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Fator de Crescimento Epidérmico/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Células NIH 3T3 , Neoplasias/enzimologia , Neoplasias/patologia , Oligopeptídeos/genética , Oligopeptídeos/metabolismo , Fosforilação , Proteínas Tirosina Quinases/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo
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