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1.
Environ Toxicol ; 39(3): 1601-1616, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38009667

RESUMO

Hepatocellular carcinoma (HCC) is a globally prevalent malignancy, marked by genetic heterogeneity and intricate tumor microenvironment interactions. In this study, we undertook a detailed single-cell analysis of six active HCC patients, highlighting strong correlations between gene expression levels and cellular characteristics. UMAP clustering revealed seven distinct cell categories with associated gene expressions. A divergence was observed in tumor cells into high and low cuproptosis groups, each associated with distinct pathways: oxidative stress for the high cuproptosis group and inflammatory and angiogenesis pathways for the low group. CellChat analysis on the TCGA-LIHC cohort displayed unique intercellular interactions among hepatocytes, T cells, and other cells, with pathways like COLLAGEN and VEGF being pivotal. Functional enrichment analyses exposed pathways enriched between cuproptosis groups, with KEGG emphasizing diseases like Parkinson's. COX survival analysis identified key prognostic genes, revealing distinct survival rates between risk groups in TCGA and GSE14520 cohorts. Mutation data highlighted missense mutations, with TTN, TP53, and CTNNB1 being the most mutated in HCC. Immune infiltration analysis via CIBERSORTx indicated differences between risk groups in NK cells, neutrophils, and other cells. Our drug sensitivity investigation showed significant correlations between model genes and drug responsiveness, emphasizing the importance of patient risk stratification for therapeutic approaches. Further, ATP6V1G1 was recognized in its role in apoptosis and migration in HCC cells. In conclusion, our findings illuminate the complexities of HCC progression, potential predictive genetic markers for drug response, and the pivotal role of ATP6V1G1, suggesting avenues for targeted therapeutic strategies in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Genômica , Hepatócitos , Apoptose , Microambiente Tumoral
2.
ACS Pharmacol Transl Sci ; 6(8): 1155-1163, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37588758

RESUMO

We investigated a novel 4-phenoxy-quinoline-based scaffold that mislocalizes the essential mitotic kinase, Aurora kinase B (AURKB). Here, we evaluated the impact of halogen substitutions (F, Cl, Br, and I) on this scaffold with respect to various drug parameters. Br-substituted LXY18 was found to be a potent and orally bioavailable disruptor of cell division, at sub-nanomolar concentrations. LXY18 prevents cytokinesis by blocking AURKB relocalization in mitosis and exhibits broad-spectrum antimitotic activity in vitro. With a favorable pharmacokinetic profile, it shows widespread tissue distribution including the blood-brain barrier penetrance and effective accumulation in tumor tissues. More importantly, it markedly suppresses tumor growth. The novel mode of action of LXY18 may eliminate some drawbacks of direct catalytic inhibition of Aurora kinases. Successful development of LXY18 as a clinical candidate for cancer treatment could enable a new, less toxic means of antimitotic attack that avoids drug resistance mechanisms.

3.
J Pharm Biomed Anal ; 232: 115415, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37120975

RESUMO

This study investigated the metabolism of LXY18, a quinolone-based compound that suppresses tumorigenesis by blocking AURKB localization. Metabolite profiling of LXY18 in liver microsomes from six species and human S9 fractions revealed that LXY18 undergoes various conserved metabolic reactions, such as N-hydroxylation, N-oxygenation, O-dealkylation, and hydrolysis, resulting in ten metabolites. These metabolites were produced through a combination of CYP450 enzymes, and non-CYP450 enzymes including CES1, and AO. Two metabolites, M1 and M2 were authenticated by chemically synthesized standards. M1 was the hydrolyzed product catalyzed by CES1 whereas M2 was a mono-N-oxidative derivative catalyzed by a CYP450 enzyme. AO was identified as the enzyme responsible for the formation of M3 with the help of AO-specific inhibitors and LXY18 analogs, 5b and 5c. M1 was the intermediate of LXY18 to produce M7, M8, M9, and M10. LXY18 potently inhibited 2C19 with an IC50 of 290 nM but had a negligible impact on the other CYP450s, indicating a low risk of drug-drug interaction. Altogether, the study provides valuable insights into the metabolic process of LXY18 and its suitability as a drug candidate. The data generated serves as a significant reference point for conducting further safety assessments and optimizing drug development.


Assuntos
Aurora Quinase B , Sistema Enzimático do Citocromo P-450 , Microssomos Hepáticos , Mitose , Humanos , Aurora Quinase B/antagonistas & inibidores , Aurora Quinase B/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Hidroxilação , Microssomos Hepáticos/metabolismo , Oxirredução
4.
Bioorg Med Chem ; 80: 117173, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36696874

RESUMO

We combined a mechanism-informed phenotypic screening (MIPS) assay with a structural simplification strategy to guide the discovery of compounds that disrupt the localization of the mitotic regulator, Aurora kinase B (AURKB), rather than inhibiting its catalytic activity. An initial hit 4-(4-methylthiophen-2-yl)-N-(4-(quinolin-4-yloxy)phenyl)phthalazin-1-amine was identified after screening an in-house library of small molecules and phenocopied the loss of function mutations in AURKB without inhibiting its catalytic activity. We isolated this hit compound activity to its 4-phenoxy-quinoline moiety. The fragment was further optimized into a class of new chemical entities that potently disrupt the mitotic localization of AURKB at low nanomolar concentrations and consequently elicit severe growth inhibition in diverse human cancer cell lines. A lead compound, N-(3-methoxy-5-(6-methoxyquinolin-4-yl)oxy)phenyl)acetamide possessed desirable pharmacokinetic properties such as AUC0-∞: 227.15 [ng∙h/mL/(mg/kg)]; Cmax: 3378.52 ng/mL T1/2: 3.52 h; and F%: 42 % and produced the AURKB-inhibitory phenotypes in a mouse xenograft model. A lead compound is a powerful tool for interrogating the regulation of AURKB and has the potential to be further developed as a first-in-class oncology therapeutic.


Assuntos
Neoplasias , Quinolinas , Humanos , Camundongos , Animais , Aurora Quinase B , Fenótipo , Aurora Quinase A/metabolismo
5.
Eur J Med Chem ; 245(Pt 1): 114904, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36413818

RESUMO

Activity-based drug screens have successfully led to the development of various inhibitors of the catalytic activity of aurora kinases (AURKs), major regulatory kinases of cell division. Disrupting the localization of AURKB, rather than its catalytic activity, represents a largely unexplored alternative approach to disabling AURKB-dependent processes. Localization disruptors could be just as specific as direct inhibitors of AURKB activity, may bypass their off-target and select on-target toxicities, and are likely less susceptible to drug resistance resulting from mutations of the AURKB catalytic site. In this study, we demonstrate that the pan-AURK inhibitor AMG900 works at a low concentration not by inhibiting the phosphorylation of H3 at Ser10, an AURKB substrate, but by disrupting the mitotic localization of AURKB. Structural deletion studies pinpoint this undescribed activity to the 2-phenoxy-3,4'-bipyridine moiety of AMG900. Guided by a mechanism-informed phenotypic screening (MIPS) assay, the drug fragment is optimized into a novel class of inhibitors that, at low nanomolar concentrations, can disable AURKB through disruption of its mitotic localization and have desirable oral PK properties. Hierarchical clustering of cell fitness profiles reveals that these compounds cluster with each other, rather than with known AURK inhibitors such as AMG900 and VX-680. Validation studies in mice demonstrate that compound 15a elicits mitotic arrest and apoptosis in NCI-H23 human lung adenocarcinoma xenografts, resulting in a pronounced suppression of tumor growth. The discovery and optimization of compounds that disrupt AURKB localization are successfully facilitated by MIPS. Our findings suggest that 2-phenoxy-3, 4'-bipyridine derivatives have the potential to be further developed as effective therapeutics for the treatment of malignancy by delocalizing AURKB.


Assuntos
Compostos Heterocíclicos , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Mitose , Aurora Quinases , Fosforilação , Aurora Quinase B
6.
Autophagy ; 19(4): 1277-1292, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36131358

RESUMO

How macroautophagy/autophagy influences neurofilament (NF) proteins in neurons, a frequent target in neurodegenerative diseases and injury, is not known. NFs in axons have exceptionally long half-lives in vivo enabling formation of large stable supporting networks, but they can be rapidly degraded during Wallerian degeneration initiated by a limited calpain cleavage. Here, we identify autophagy as a previously unrecognized pathway for NF subunit protein degradation that modulates constitutive and inducible NF turnover in vivo. Levels of NEFL/NF-L, NEFM/NF-M, and NEFH/NF-H subunits rise substantially in neuroblastoma (N2a) cells after blocking autophagy either with the phosphatidylinositol 3-kinase (PtdIns3K) inhibitor 3-methyladenine (3-MA), by depleting ATG5 expression with shRNA, or by using both treatments. In contrast, activating autophagy with rapamycin significantly lowers NF levels in N2a cells. In the mouse brain, NF subunit levels increase in vivo after intracerebroventricular infusion of 3-MA. Furthermore, using tomographic confocal microscopy, immunoelectron microscopy, and biochemical fractionation, we demonstrate the presence of NF proteins intra-lumenally within autophagosomes (APs), autolysosomes (ALs), and lysosomes (LYs). Our findings establish a prominent role for autophagy in NF proteolysis. Autophagy may regulate axon cytoskeleton size and responses of the NF cytoskeleton to injury and disease.


Assuntos
Autofagia , Filamentos Intermediários , Camundongos , Animais , Autofagia/fisiologia , Proteólise , Filamentos Intermediários/metabolismo , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , Neurônios/metabolismo
7.
Int J Mol Sci ; 23(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36292957

RESUMO

Small molecule inhibitors of aurora kinases are currently being investigated in oncology clinical trials. The long-term effects of these inhibitors on proliferating euploid cells have not been adequately studied. We examined the effect of the reversible pan-aurora kinase inhibitor VX-680 on p53-competent human euploid cells. Circumscribed treatment with VX-680 blocked cytokinesis and arrested cells in G1 or a G1-like status. Approximately 70% of proliferatively arrested cells had 4N DNA content and abnormal nuclei. The remaining 30% of cells possessed 2N DNA content and normal nuclei. The proliferative arrest was not due to the activation of the tumor suppressor Rb and was instead associated with rapid induction of the p53-p21 pathway and p16. The induction was particularly evident in cells with nuclear abnormalities but was independent of activation of the DNA damage response. All of these effects were correlated with the potent inhibition of aurora kinase B. After release from VX-680, the cells with normal nuclei robustly resumed proliferation whereas the cells with abnormal nuclei underwent senescence. Irrespective of their nuclear morphology or DNA content, cells pre-treated with VX-680 failed to grow in soft agar or form tumors in mice. Our findings indicate that an intermittent treatment strategy might minimize the on-target side effects of Aurora Kinase B (AURKB) inhibitory therapies. The strategy allows a significant fraction of dividing normal cells to resume proliferation.


Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Camundongos , Animais , Aurora Quinase B/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteínas Serina-Treonina Quinases , Ágar , Apoptose , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Neoplasias/tratamento farmacológico , DNA/farmacologia , Linhagem Celular Tumoral
8.
Diagn Pathol ; 17(1): 71, 2022 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-36153594

RESUMO

BACKGROUND: Hyperparathyroidism-Jaw Tumor (HPT-JT) is caused by inactivating germline mutations of CDC73. This hereditary disease can present with a range of symptoms. Jaw ossifying fibroma (OF) is one of the most important clinical presentations, affecting 30% of HPT-JT patients. However, OF is easily confused with other fibro-osseous lesions (FOLs) of the jaw. The correct diagnosis of HPT-JT is a real challenge and must be confirmed by genetic testing. CASE PRESENTATION: A female proband and her father suffered from multiple and recurrent FOLs in the jaw. Considering well demarcated margin and heterogeneous calcified substance lying in a variable density of fibrous stroma, we reached the diagnosis of jaw OF through radiologic and microscopic analyses. Additionally, the proband presented with chronic anemia resulting from menorrhagia, as well as renal mixed epithelial and stromal tumor (MEST). Two patients both presented with no evidence of Hyperparathyroidism (HPT). A germline start codon mutation (c.1A > G) of CDC73 was identified in them. Copy number loss at the CDC73 gene locus was verified in the jaw tumor sample of the proband. CONCLUSION: Regardless of whether HPT manifestations are present, patients with heritable jaw OF may be at risk for HPT-JT. Genetic testing should be adopted to confirm the diagnosis. Early recognition of HPT-JT helps to better develop tailored treatment plans and surveillance programs.


Assuntos
Fibroma Ossificante , Hiperparatireoidismo , Neoplasias Maxilomandibulares , Neoplasias Renais , Adenoma , Códon de Iniciação , Feminino , Fibroma , Humanos , Hiperparatireoidismo/diagnóstico , Hiperparatireoidismo/genética , Hiperparatireoidismo/patologia , Neoplasias Maxilomandibulares/diagnóstico , Neoplasias Maxilomandibulares/genética , Neoplasias Maxilomandibulares/patologia , Neoplasias Renais/diagnóstico , Neoplasias Renais/genética , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética
9.
ACS Med Chem Lett ; 13(7): 1091-1098, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35859866

RESUMO

We used mechanism-informed phenotypic screening to identify and optimize compounds that phenocopy the genetic depletion of the mitotic aurora kinase B (AURKB) kinase. After assaying nine aryl fused seven-membered lactam compounds, we identified a hit compound 6a that was subsequently optimized to five lead compounds with low nanomolar activity, represented by the lead compound 6v (19 nM). With excellent drug-like properties, these compounds reproduced the loss of function in phenotypes of AURKB and exhibited potent cytotoxic activities in various cancer cell lines. Collectively, these data support that seven-membered lactam-based analogs might be valuable for further development as a new type of antimitotic agents for the treatment of cancer.

10.
Biomed Pharmacother ; 147: 112645, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35051862

RESUMO

Plants are a rich source for bioactive compounds. However, plant extracts can harbor a mixture of bioactive molecules that promote divergent phenotypes and potentially have confounding effects in bioassays. Even with further purification and identification, target deconvolution can be challenging. Corynoline and acetylcorynoline, are phytochemicals that were previously isolated through a screen for compounds able to induce mitotic arrest and polyploidy in oncogene expressing retinal pigment epithelial (RPE) cells. Here, we shed light on the mechanism by which these phytochemicals can attack human cancer cells. Mitotic arrest was coincident to the induction of centrosome amplification and declustering, causing multi-polar spindle formation. Corynoline was demonstrated to have true centrosome declustering activity in a model where A549 cells were chemically induced to have more than a regular complement of centrosomes. Corynoline could inhibit the centrosome clustering required for pseudo-bipolar spindle formation in these cells. The activity of AURKB, but not AURKA or polo-like kinase 4, was diminished by corynoline. It only partially inhibited AURKB, so it may be a partial antagonist or corynoline may work upstream on an unknown regulator of AURKB activity or localization. Nonetheless, corynoline and acetylcorynoline inhibited the viability of a variety of human cancer derived cell lines. These phytochemicals could serve as prototypes for a next-generation analog with improved potency, selectivity or in vivo bioavailability. Such an analog could be useful as a non-toxic component of combination therapies where inhibiting the chromosomal passenger protein complex is desired.


Assuntos
Aurora Quinase B/efeitos dos fármacos , Alcaloides de Berberina/farmacologia , Mitose/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Poliploidia , Células A549 , Apoptose/efeitos dos fármacos , Aurora Quinase A/efeitos dos fármacos , Linhagem Celular Tumoral , Centrossomo/efeitos dos fármacos , Humanos
11.
J Nat Prod ; 84(8): 2312-2320, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-34406008

RESUMO

To identify novel bioactive compounds, an image-based, cell culture screening of natural product extracts was conducted. Specifically, our screen was designed to identify phytochemicals that might phenocopy inhibition of the chromosomal passenger protein complex in eliciting mitotic and cytokinetic defects. A known alkaloid, scoulerine, was identified from the rhizomes of the plant Corydalis decumbens as being able to elicit a transient mitotic arrest followed by either apoptosis induction or polyploidy. In examining the mitotic abnormality further, we observed that scoulerine could elicit supernumerary centrosomes during mitosis, but not earlier in the cell cycle. The localization of NUMA1 at spindle poles was also inhibited, suggesting diminished potential for microtubule recruitment and spindle-pole focusing. Polyploid cells emerged subsequent to cytokinetic failure. The concentration required for scoulerine to elicit all its cell division phenotypes was similar, and an examination of related compounds highlighted the requirement for proper positioning of a hydroxyl and a methoxy group about an aromatic ring for activity. Mechanistically, scoulerine inhibited AURKB activity at concentrations that elicited supernumerary centrosomes and polyploidy. AURKA was only inhibited at higher concentrations, so AURKB inhibition is the likely mechanism by which scoulerine elicited division defects. AURKB inhibition was never complete, so scoulerine may be a suboptimal AURK inhibitor or work upstream of the chromosomal passenger protein complex to reduce AURKB activity. Scoulerine inhibited the viability of a variety of human cancer cell lines. Collectively, these findings uncover a previously unknown activity of scoulerine that could facilitate targeting human cancers. Scoulerine, or a next-generation analogue, may be useful as a nontoxic component of combination therapies where inhibiting the chromosomal passenger protein complex is desired.


Assuntos
Aurora Quinase A/antagonistas & inibidores , Aurora Quinase B/antagonistas & inibidores , Alcaloides de Berberina/farmacologia , Citocinese/efeitos dos fármacos , Mitose/efeitos dos fármacos , Alcaloides de Berberina/isolamento & purificação , Linhagem Celular , China , Corydalis/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Humanos , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Rizoma/química
12.
PLoS One ; 16(3): e0248355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33760847

RESUMO

A synthetic lethal effect arises when a cancer-associated change introduces a unique vulnerability to cancer cells that makes them unusually susceptible to a drug's inhibitory activity. The synthetic lethal approach is attractive because it enables targeting of cancers harboring specific genomic or epigenomic alterations, the products of which may have proven refractory to direct targeting. An example is cancer driven by overexpression of MYC. Here, we conducted a high-content screen for compounds that are synthetic lethal to elevated MYC using a small-molecule library to identify compounds that are closely related to, or are themselves, regulatory-approved drugs. The screen identified dimethylfasudil, a potent and reversible inhibitor of Rho-associated kinases, ROCK1 and ROCK2. Close analogs of dimethylfasudil are used clinically to treat neurologic and cardiovascular disorders. The synthetic lethal interaction was conserved in rodent and human cell lines and could be observed with activation of either MYC or its paralog MYCN. The synthetic lethality seems specific to MYC overexpressing cells as it could not be substituted by a variety of oncogenic manipulations and synthetic lethality was diminished by RNAi-mediated depletion of MYC in human cancer cell lines. Collectively, these data support investigation of the use of dimethylfasudil as a drug that is synthetic lethal for malignancies that specifically overexpress MYC.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas c-myc/genética , Mutações Sintéticas Letais/efeitos dos fármacos , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Linhagem Celular Tumoral , Humanos
13.
Exp Cell Res ; 394(1): 112112, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32473226

RESUMO

Inhibition of Aurora-B kinase is a synthetic lethal therapy for tumors that overexpress the MYC oncoprotein. It is currently unclear whether co-occurring oncogenic alterations might influence this synthetic lethality by conferring more or less potency in the killing of tumor cells. To identify such modifiers, isogenic cell lines were utilized to test a variety of cancer genes that have been previously demonstrated to promote survival under conditions of cellular stress, contribute to chemoresistance and/or suppress MYC-primed apoptosis. It was found that Bcl-2 and Bcl-xL, two antiapoptotic members of the Bcl-2 family, can partially suppress the synthetic lethality, but not multinucleation, elicited by a pan-aurora kinase inhibitor, VX-680. Suppression was show to stem from the inhibition of autophagy, specifically in multinucleated cells, rather than a general inhibition of apoptosis. The anti-autophagic activity of Bcl-2 also impacted polyploid cell recovery in colony-forming assays, suggesting a route of escape from MYC-VX-680 synthetic lethality that may have clinical consequences. These findings expand on previous conclusions that autophagic death of VX-680-induced polyploid cells is mediated by Atg6. Bcl-2 and Bcl-xL negatively modulate MYC-VX-680 synthetic lethality and it is the anti-autophagic activity of these two Bcl-2 family proteins, specifically in multinucleate cells, that contributes to resistance to Aurora kinase-targeting drugs.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína bcl-X/metabolismo , Proteínas Reguladoras de Apoptose/genética , Proteína Beclina-1/genética , Linhagem Celular Tumoral , Humanos , Proteínas de Membrana/metabolismo
14.
Medicine (Baltimore) ; 99(3): e18767, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011466

RESUMO

RATIONALE: About one-third of the lung tumors are staged as locally advanced at the time of initial diagnosis; however, the optimal induction treatment before curative resection has not been elucidated. To date, the evidence regarding the preoperative apatinib plus S-1 for locally advanced pulmonary adenocarcinoma is scarce. PATIENT CONCERNS: A 29-year-old female was admitted because of persistent cough, sputum, and chest distress for 2 months. DIAGNOSES: Primary pulmonary adenocarcinoma (cT3N2M0, IIIB) with unknown driver gene mutation status. INTERVENTIONS: The patient had received 4 months of neoadjuvant therapy using oral apatinib (425 mg daily) plus S-1 (60 mg, twice daily for 4 weeks with a 2-week drug-free interval), followed by anatomical lobectomy with curative intent. Adjuvant apatinib (425 mg daily for a month, and 250 mg daily for another month) plus S-1 at the same dosage were administered for 2 months. Thereafter, maintenance of low-dose S-1 monotherapy (40 mg, twice daily for 4 weeks with a 2-week drug-free interval) was continued for 6 months. OUTCOMES: The adverse events were tolerable and well-controlled. A postoperative recurrence-free survival for 2 years and a half up to now was indicated. LESSONS: Preoperative apatinib plus S-1 showed efficacy in locally advanced pulmonary adenocarcinoma. However, high-quality trials are warranted before the recommendation of this therapeutic regimen.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/cirurgia , Ácido Oxônico/administração & dosagem , Piridinas/administração & dosagem , Tegafur/administração & dosagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica , Combinação de Medicamentos , Feminino , Humanos , Terapia Neoadjuvante , Pneumonectomia
15.
Autophagy ; 15(3): 543-557, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30269645

RESUMO

Autophagy-lysosome pathway (ALP) disruption is considered pathogenic in multiple neurodegenerative diseases; however, current methods are inadequate to investigate macroautophagy/autophagy flux in brain in vivo and its therapeutic modulation. Here, we describe a novel autophagy reporter mouse (TRGL6) stably expressing a dual-fluorescence-tagged LC3 (tfLC3, mRFP-eGFP-LC3) by transgenesis selectively in neurons. The tfLC3 probe distributes widely in the central nervous system, including spinal cord. Expression levels were similar to endogenous LC3 and induced no detectable ALP changes. This ratiometric reporter registers differential pH-dependent changes in color as autophagosomes form, fuse with lysosomes, acidify, and degrade substrates within autolysosomes. We confirmed predicted changes in neuronal autophagy flux following specific experimental ALP perturbations. Furthermore, using a third fluorescence label in TRGL6 brains to identify lysosomes by immunocytochemistry, we validated a novel procedure to detect defective autolysosomal acidification in vivo. Thus, TRGL6 mice represent a unique tool to investigate in vivo ALP dynamics in specific neuron populations in relation to neurological diseases, aging, and disease modifying agents. Abbreviations: ACTB: actin, beta; AD: Alzheimer disease; AL: autolysosomes; ALP: autophagy-lysosome pathway; AP: autophagosome; APP: amyloid beta (Abeta) precursor protein; ATG5: autophagy related 5; ATG7: autophagy related 7; AV: autophagic vacuoles; CNS: central nervous system; CTSD: cathepsin D; CQ: chloroquine; DMEM: Dulbecco's modified Eagle's medium; GFP: green fluorescent protein; GABARAP: gamma-aminobutyric acid receptor associated protein; GABARAPL2/GATE16: gamma-aminobutyric acid (GABA) receptor-associated protein-like 2; ICC: immunocytochemistry; ICV: intra-cerebroventricular; LAMP2: lysosomal-associated membrane protein 2; Leup: leupeptin; LY: lysosomes; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; MTOR: mechanistic target of rapamycin kinase; RBFOX3/NeuN: RNA binding protein, fox-1 homolog (C. elegans) 3; RFP: red fluorescent protein; RPS6KB1: ribosomal protein S6 kinase, polypeptide 1; SDS-PAGE: sodium dodecyl sulfate-polyacrylamide gel electrophoresis; SQSTM1: sequestosome 1; tfLC3: mRFP-eGFP-LC3; TRGL6: Thy1 mRFP eGFP LC3-line 6; PCR: polymerase chain reaction; PD: Parkinson disease.


Assuntos
Autofagia , Encéfalo/metabolismo , Lisossomos/química , Proteínas Associadas aos Microtúbulos/genética , Neurônios/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Encéfalo/citologia , Química Encefálica , Células Cultivadas , Cloroquina/farmacologia , Corantes Fluorescentes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Morfolinas/farmacologia , Neurônios/química , Neurônios/citologia , Neurônios/efeitos dos fármacos , Proteína Vermelha Fluorescente
16.
ACS Chem Neurosci ; 10(1): 528-536, 2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30346715

RESUMO

Alzheimer's disease (AD) is characterized by extracellular deposition of amyloid plaques, which are predominantly composed of amyloid-ß (Aß) peptide derived from amyloid precursor protein (APP) cleavage. APP interacts with tropomyosin receptor kinase A, a neurotrophic receptor associated with gangliosides and mediating neuronal survival and differentiation through the extracellular signal-regulated protein kinase (ERK) pathway. The ganglioside Hp-s1's analogue Hp-s1A exerts neuritogenic activity; however, its effect on AD pathology remains unknown. To test the hypothesis that Hp-s1A is a potential candidate to treat AD, we established the AD-modeled cell line by expressing human Swedish and Indiana APP gene (APP-Swe/Ind) in N2a mouse neuroblastoma cells. The cells were treated with Hp-s1A or monosialoganglioside GM1 for comparison. The AD model cells expressing APP-Swe/Ind exhibited a significant reduction in viability, as well as neurite outgrowth rate, in comparison to the control cells expressing APP-695. APP C-terminal fragment-ß (CTFß) and Aß42 were increased in the AD cell lysates and the culture media, respectively. With the treatment of either Hp-s1A or GM1 at 1 µM, the AD model cells showed a significant increase in viability; however, only Hp-s1A reduced CTFß levels in these cells. Further analysis of the culture media revealed that Hp-s1A also reduced Aß42 production from AD model cells. The phosphorylation of ERK was elevated and the neurite outgrowth rate was restored with Hp-s1A treatment. In conclusion, the ganglioside analogue Hp-s1A inhibited amyloidogenic processing of APP and promoted neurotrophic activity and survival of AD model cells. Hp-s1A has great potential in AD therapeutic development.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Gangliosídeos/farmacologia , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Gangliosídeos/metabolismo , Humanos , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fragmentos de Peptídeos/efeitos dos fármacos , Fragmentos de Peptídeos/metabolismo , Placa Amiloide/tratamento farmacológico , Placa Amiloide/metabolismo , Presenilina-1/genética
17.
Medicine (Baltimore) ; 97(43): e12950, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30412112

RESUMO

RATIONALE: Asymptomatic, isolated, and thin-walled cystic lung cancer with extensive extrapulmonary metastasis is rare, and the risk of pulmonary cyst developing into lung cancer is poorly understood. The efficacy of apatinib for end-stage pulmonary adenosquamous carcinoma has not been clarified yet. PATIENT CONCERNS: We herein report a rare case of primary lung cancer that appeared as an isolated thin-walled cystic lesion on computed tomography (CT) image, who was initially misdiagnosed as having pulmonary cyst empirically. DIAGNOSES: Fluorine-18-fluorodeoxyglucose-positron emission tomography and CT-guided liver biopsy of the patient revealed extra-pulmonary metastasis of lung cancer. INTERVENTIONS: Eight cycles of cisplatin-based chemotherapy were administered, followed by oral apatinib for 6 months. Thereafter, best supportive care was given for this patient. OUTCOMES: The pulmonary cystic lesion indicated stable disease through the therapy, but the hepatic tumors were progressed gradually after anticancer treatment. The patient died 16 months after the correct diagnosis. LESSONS: Solitary thin-walled cystic lung cancer should be kept in mind during the differential diagnosis of pulmonary cavitary lesions. Chest CT alone is insufficient for surveillance of these cystic diseases. Timely biopsy and resection are essential to avoid delayed management. Besides, apatinib may play a role in the treatment of end-stage pulmonary adenosquamous carcinoma.


Assuntos
Carcinoma Adenoescamoso/secundário , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Carcinoma Adenoescamoso/tratamento farmacológico , Carcinoma Adenoescamoso/patologia , Diagnóstico Tardio , Evolução Fatal , Humanos , Neoplasias Hepáticas/patologia , Dor Lombar , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia Computadorizada por Raios X , Imagem Corporal Total
18.
Hum Mol Genet ; 26(5): 843-859, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28062666

RESUMO

2-hydroxypropyl-ß-cyclodextrin (CYCLO), a modifier of cholesterol efflux from cellular membrane and endo-lysosomal compartments, reduces lysosomal lipid accumulations and has therapeutic effects in animal models of Niemann-Pick disease type C and several other neurodegenerative states. Here, we investigated CYCLO effects on autophagy in wild-type mice and TgCRND8 mice-an Alzheimer's Disease (AD) model exhibiting ß-amyloidosis, neuronal autophagy deficits leading to protein and lipid accumulation within greatly enlarged autolysosomes. A 14-day intracerebroventricular administration of CYCLO to 8-month-old TgCRND8 mice that exhibit moderately advanced neuropathology markedly diminished the sizes of enlarged autolysosomes and lowered their content of GM2 ganglioside and Aß-immunoreactivity without detectably altering amyloid precursor protein processing or extracellular Aß/ß-amyloid burden. We identified two major actions of CYCLO on autophagy underlying amelioration of lysosomal pathology. First, CYCLO stimulated lysosomal proteolytic activity by increasing cathepsin D activity, levels of cathepsins B and D and two proteins known to interact with cathepsin D, NPC1 and ABCA1. Second, CYCLO impeded autophagosome-lysosome fusion as evidenced by the accumulation of LC3, SQSTM1/p62, and ubiquitinated substrates in an expanded population of autophagosomes in the absence of greater autophagy induction. By slowing substrate delivery to lysosomes, autophagosome maturational delay, as further confirmed by our in vitro studies, may relieve lysosomal stress due to accumulated substrates. These findings provide in vivo evidence for lysosomal enhancing properties of CYCLO, but caution that prolonged interference with cellular membrane fusion/autophagosome maturation could have unfavorable consequences, which might require careful optimization of dosage and dosing schedules.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Amiloidose/tratamento farmacológico , Ciclodextrinas/administração & dosagem , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides , Amiloidose/metabolismo , Animais , Autofagia/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Modelos Animais de Doenças , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia
19.
Brain ; 137(Pt 12): 3300-18, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25270989

RESUMO

Autophagy, the major lysosomal pathway for the turnover of intracellular organelles is markedly impaired in neurons in Alzheimer's disease and Alzheimer mouse models. We have previously reported that severe lysosomal and amyloid neuropathology and associated cognitive deficits in the TgCRND8 Alzheimer mouse model can be ameliorated by restoring lysosomal proteolytic capacity and autophagy flux via genetic deletion of the lysosomal protease inhibitor, cystatin B. Here we present evidence that macroautophagy is a significant pathway for lipid turnover, which is defective in TgCRND8 brain where lipids accumulate as membranous structures and lipid droplets within giant neuronal autolysosomes. Levels of multiple lipid species including several sphingolipids (ceramide, ganglioside GM3, GM2, GM1, GD3 and GD1a), cardiolipin, cholesterol and cholesteryl esters are elevated in autophagic vacuole fractions and lysosomes isolated from TgCRND8 brain. Lipids are localized in autophagosomes and autolysosomes by double immunofluorescence analyses in wild-type mice and colocalization is increased in TgCRND8 mice where abnormally abundant GM2 ganglioside-positive granules are detected in neuronal lysosomes. Cystatin B deletion in TgCRND8 significantly reduces the number of GM2-positive granules and lowers the levels of GM2 and GM3 in lysosomes, decreases lipofuscin-related autofluorescence, and eliminates giant lipid-containing autolysosomes while increasing numbers of normal-sized autolysosomes/lysosomes with reduced content of undigested components. These findings have identified macroautophagy as a previously unappreciated route for delivering membrane lipids to lysosomes for turnover, a function that has so far been considered to be mediated exclusively through the endocytic pathway, and revealed that autophagic-lysosomal dysfunction in TgCRND8 brain impedes lysosomal turnover of lipids as well as proteins. The amelioration of lipid accumulation in TgCRND8 by removing cystatin B inhibition on lysosomal proteases suggests that enhancing lysosomal proteolysis improves the overall environment of the lysosome and its clearance functions, which may be possibly relevant to a broader range of lysosomal disorders beyond Alzheimer's disease.


Assuntos
Autofagia/fisiologia , Encéfalo/metabolismo , Metabolismo dos Lipídeos/fisiologia , Lisossomos/metabolismo , Doença de Alzheimer/patologia , Amiloide/metabolismo , Animais , Autofagia/genética , Encéfalo/patologia , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Proteólise
20.
Nat Cell Biol ; 14(6): 567-74, 2012 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-22581054

RESUMO

Overexpression of MYC transforms cells in culture, elicits malignant tumours in experimental animals and is found in many human tumours. We now report the paradoxical finding that this powerful oncogene can also act as a suppressor of cell motility, invasiveness and metastasis. Overexpression of MYC stimulated proliferation of breast cancer cells both in culture and in vivo as expected, but inhibited motility and invasiveness in culture, and lung and liver metastases in xenografted tumours. We show further that MYC represses transcription of both subunits of αvß3 integrin, and that exogenous expression of ß3 integrin in human breast cancer cells that do not express this integrin rescues invasiveness and migration when MYC is downregulated. These data uncover an unexpected function of MYC, provide an explanation for the hitherto puzzling literature on the relationship between MYC and metastasis, and reveal a variable that could influence the development of therapies that target MYC.


Assuntos
Integrina alfa5/metabolismo , Integrina beta3/metabolismo , Neoplasias/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transcrição Gênica , Animais , Linhagem Celular Tumoral , Matriz Extracelular/metabolismo , Inativação Gênica , Humanos , Integrina alfa5/genética , Integrina beta3/genética , Camundongos , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias/genética , Neoplasias/patologia , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética
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