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1.
Helicobacter ; 29(4): e13121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39097924

RESUMO

BACKGROUND: Current guidelines recommend bismuth-containing quadruple therapy for patients newly diagnosed with Helicobacter pylori (H. pylori) infection. We aimed to compare the efficacy and safety of tetracycline administered three times daily versus four times daily in bismuth-containing quadruple therapy for first-line treatment of H. pylori infection. METHODS: This multicenter, noninferiority, randomized controlled study, conducted in China, recruited treatment-naïve adults with H. pylori infection, randomized 1:1 into two treatment groups to receive either of the following bismuth-containing quadruple therapies: esomeprazole 20 mg twice-daily; bismuth 220 mg twice-daily; amoxicillin 1000 mg twice-daily; and tetracycline 500 mg three times daily (TET-T) versus 500 mg four times daily (TET-F). At least 6 weeks post-treatment, a 13C-urea breath test was performed to evaluate H. pylori eradication. RESULTS: In total, 406 patients were randomly assigned to the two treatment groups. Intention-to-treat eradication rates were 91.63% (186/203; 95% confidence interval [CI] 87.82%-95.44%) versus 90.15% (183/203; 95% CI 86.05%-94.25%) (p = 0.0005) and per-protocol eradication rates were 95.34% (184/193; 95% CI 92.36%-98.31%) versus 95.72% (179/187; 95% CI 92.82%-98.62%) (p = 0.0002) for the TET-T and TET-F group, respectively. TET-T-treated patients had a lower incidence of adverse effects than TET-F-treated patients (21.61% vs. 31.63%, p = 0.024), with no significant differences in compliance to treatment between the groups. CONCLUSION: As a first-line therapy for H. pylori infection, the eradication rate of the TET-T therapy was noninferior to that of the TET-F therapy while significantly reducing the incidence of adverse reactions. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05431075.


Assuntos
Antibacterianos , Bismuto , Quimioterapia Combinada , Infecções por Helicobacter , Helicobacter pylori , Tetraciclina , Humanos , Infecções por Helicobacter/tratamento farmacológico , Tetraciclina/uso terapêutico , Tetraciclina/administração & dosagem , Tetraciclina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Feminino , Bismuto/uso terapêutico , Bismuto/efeitos adversos , Antibacterianos/uso terapêutico , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Adulto , Helicobacter pylori/efeitos dos fármacos , Resultado do Tratamento , China , Amoxicilina/uso terapêutico , Amoxicilina/administração & dosagem , Esquema de Medicação , Esomeprazol/uso terapêutico , Esomeprazol/administração & dosagem , Idoso , Adulto Jovem , Testes Respiratórios , Inibidores da Bomba de Prótons/uso terapêutico , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/efeitos adversos
2.
Helicobacter ; 29(1): e13055, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39078641

RESUMO

BACKGROUND: Large language models (LLMs) are promising medical counseling tools, but the reliability of responses remains unclear. We aimed to assess the feasibility of three popular LLMs as counseling tools for Helicobacter pylori infection in different counseling languages. MATERIALS AND METHODS: This study was conducted between November 20 and December 1, 2023. Three large language models (ChatGPT 4.0 [LLM1], ChatGPT 3.5 [LLM2], and ERNIE Bot 4.0 [LLM3]) were input 15 H. pylori related questions each, once in English and once in Chinese. Each chat was conducted using the "New Chat" function to avoid bias from correlation interference. Responses were recorded and blindly assigned to three reviewers for scoring on three established Likert scales: accuracy (ranged 1-6 point), completeness (ranged 1-3 point), and comprehensibility (ranged 1-3 point). The acceptable thresholds for the scales were set at a minimum of 4, 2, and 2, respectively. Final various source and interlanguage comparisons were made. RESULTS: The overall mean (SD) accuracy score was 4.80 (1.02), while 1.82 (0.78) for completeness score and 2.90 (0.36) for comprehensibility score. The acceptable proportions for the accuracy, completeness, and comprehensibility of the responses were 90%, 45.6%, and 100%, respectively. The acceptable proportion of overall completeness score for English responses was better than for Chinese responses (p = 0.034). For accuracy, the English responses of LLM3 were better than the Chinese responses (p = 0.0055). As for completeness, the English responses of LLM1 was better than the Chinese responses (p = 0.0257). For comprehensibility, the English responses of LLM1 was better than the Chinese responses (p = 0.0496). No differences were found between the various LLMs. CONCLUSIONS: The LLMs responded satisfactorily to questions related to H. pylori infection. But further improving completeness and reliability, along with considering language nuances, is crucial for optimizing overall performance.


Assuntos
Aconselhamento , Infecções por Helicobacter , Helicobacter pylori , Idioma , Humanos , Infecções por Helicobacter/diagnóstico , Reprodutibilidade dos Testes , Inquéritos e Questionários
3.
Ying Yong Sheng Tai Xue Bao ; 32(6): 2061-2069, 2021 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-34212612

RESUMO

The adaptation strategy of seedlings plays a decisive role in population regeneration. Machilus nanmu is a tree species belonging to Lauraceae, which is national class Ⅱ protected species and one of the dominant species in the evergreen broadleaved forest in Jinyun Mountain, Chongqing. Therefore, it is of great significance to understand the adaptation strategies of M. nanmu seedlings to maintain population regeneration and protect the biodiversity of evergreen broadleaved forest. We studied the temporal dynamics of early adaptation strategy of M. nanmu in Jinyun Mountain in Chongqing and its response to heterogeneous habitats from the perspective of morphology and biomass allocation. The seedlings of M. nanmu were classified into different age stages (stage 1: 1-3 a; stage 2: 4-6 a; stage 3: 7-9 a) under different canopy environments (gap/understory). Stem configurations (except branch angle) and leaf inclination angle of M. nanmu seedlings in the gap were significantly greater than understory at stages 2 and 3. Root configurations (except root diameter) and leaf area were significantly greater than that in the understory at stages 1 and 2. Specific leaf area in the gap was significantly smaller than understory at all three stages. Across all the conditions, biomass distribution was dominated by leaves. From the stage 2, stem biomass distribution of M. nanmu seedlings in the gap was increased, while root biomass distribution was decreased. There was no significant variation in root biomass of M. nanmu seedlings in the understory. The coordination among different organs of M. nanmu seedlings would help their adaptation to different habitats. Root and leaf of M. nanmu seedlings in the gap were significantly correlated, with the correlation changing from positive to negative as the age increased. While in the understory, there was significant positive correlation between root and stem, but no correlation between root and leaf. The slope of SMA equation of branch weight and branch length had significant difference under different canopy environments only at stage 3, while the slope of SMA equation of leaf and root biomass and configuration had no significant difference. Most of the SMA equation intercepts between biomass and configuration differed significantly at stage 2.


Assuntos
Lauraceae , Plântula , Biomassa , Florestas , Folhas de Planta , Árvores
4.
Autophagy ; 17(12): 4323-4340, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33977871

RESUMO

Macroautophagy/autophagy plays an important role during the development of human cancer. BECN1 (beclin 1), a core player in autophagy regulation, is downregulated in many kinds of malignancy. The underlying mechanism, however, has not been fully illuminated. Here, we found that CUL3 (cullin 3), an E3 ubiquitin ligase, could interact with BECN1 and promote the K48-linked ubiquitination and degradation of this protein; In addition, CUL3 led to a decrease in autophagic activity through downregulating BECN1. We also found that KLHL38 was a substrate adaptor of the CUL3 E3 ligase complex-mediated ubiquitination and degradation of BECN1. In breast and ovarian cancer, CUL3 could promote the proliferation of tumor cells, and the expression of CUL3 was related to poor prognosis in patients. Our study reveals the underlying mechanism of BECN1 ubiquitination and degradation that affects autophagic activity and subsequently leads to tumor progression, providing a novel therapeutic strategy that regulates autophagy to combat cancer.Abbreviations: ATG: autophagy-related BECN1: beclin 1 CHX: cycloheximide CoIP: co-immunoprecipitation CUL3: cullin 3 IP: immunoprecipitation MS: mass spectrometry PtdIns3K: phosphatidylinositol 3-kinase UPS: ubiquitin-proteasome system.


Assuntos
Autofagia , Proteínas Culina , Autofagia/fisiologia , Proteína Beclina-1/metabolismo , Proteínas Culina/metabolismo , Humanos , Ubiquitina/metabolismo , Ubiquitinação
5.
Nat Commun ; 8(1): 1159, 2017 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-29079782

RESUMO

Autophagy is a degradative pathway that delivers cellular components to the lysosome for degradation. The role of autophagy in cell differentiation is poorly understood. Here we show that CaMKII can directly phosphorylate Beclin 1 at Ser90 to promote K63-linked ubiquitination of Beclin 1 and activation of autophagy. Meanwhile, CaMKII can also promote K63-linked ubiquitination of inhibitor of differentiation 1/2 (Id-1/2) by catalyzing phosphorylation of Id proteins and recruiting TRAF-6. Ubiquitinated Id-1/Id-2 can then bind to p62 and be transported to autolysosomes for degradation. Id degradation promotes the differentiation of neuroblastoma cells and reduces the proportion of stem-like cells. Our study proposes a mechanism by which autophagic degradation of Id proteins can regulate cell differentiation. This suggests that targeting of CaMKII and the regulation of autophagic degradation of Id may be an effective therapeutic strategy to induce cell differentiation in neuroblastoma.


Assuntos
Proteína Beclina-1/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína 1 Inibidora de Diferenciação/metabolismo , Proteína 2 Inibidora de Diferenciação/metabolismo , Neuroblastoma/metabolismo , Animais , Autofagia , Diferenciação Celular , Fibroblastos/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Lisina/química , Lisossomos/metabolismo , Camundongos , Fosforilação , Proteínas de Ligação a RNA/metabolismo , Serina/química , Fator 6 Associado a Receptor de TNF/metabolismo , Ubiquitinação
6.
Oncotarget ; 6(9): 6944-58, 2015 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-25749514

RESUMO

Side population (SP) contains cancer stem-like cells (CSLCs). In this study, we characterized SP cells from nasopharyngeal carcinoma (NPC) cell lines and found that SP cells had a higher self-renewal ability in vitro and greater tumorigenicity in vivo. The AKT pathway was activated in NPC SP cells. DC120, a 2-pyrimidyl-5-amidothiazole inhibitor of the ATP binding site of AKT, inhibited phosphorylation of FKHRL1 and GSK-3ß. DC120 inhibited SP fraction, the sphere-forming ability in vitro and growth of primary xenografts as well as secondary xenografts' tumor recurrence. This inhibition was accompanied by reduced expression of stem-related gene Sox2 due to induction of p27 and miR-30a. A combination of DC120 and CDDP more effectively inhibited NPC cells compared with monotherapy in vitro and in vivo. Clinical evaluation of DC120 is warranted.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Nasofaríngeas/enzimologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Pirimidinas/química , Fatores de Transcrição SOXB1/metabolismo , Tiazóis/química , Trifosfato de Adenosina/química , Animais , Antineoplásicos/química , Sítios de Ligação , Carcinoma , Separação Celular , Regulação para Baixo , Citometria de Fluxo , Inativação Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Humanos , Concentração Inibidora 50 , Camundongos , Camundongos SCID , Carcinoma Nasofaríngeo , Recidiva Local de Neoplasia , Fenótipo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Autophagy ; 11(2): 239-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25701194

RESUMO

PTEN (phosphatase and tensin homolog), a tumor suppressor frequently mutated in human cancer, has various cytoplasmic and nuclear functions. PTEN translocates to the nucleus from the cytoplasm in response to oxidative stress. However, the mechanism and function of the translocation are not completely understood. In this study, topotecan (TPT), a topoisomerase I inhibitor, and cisplatin (CDDP) were employed to induce DNA damage. The results indicate that TPT or CDDP activates ATM (ATM serine/threonine kinase), which phosphorylates PTEN at serine 113 and further regulates PTEN nuclear translocation in A549 and HeLa cells. After nuclear translocation, PTEN induces autophagy, in association with the activation of the p-JUN-SESN2/AMPK pathway, in response to TPT. These results identify PTEN phosphorylation by ATM as essential for PTEN nuclear translocation and the subsequent induction of autophagy in response to DNA damage.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Autofagia/efeitos dos fármacos , Dano ao DNA , PTEN Fosfo-Hidrolase/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Antineoplásicos/farmacologia , Autofagia/fisiologia , Cisplatino/farmacologia , Humanos , Fosforilação/efeitos dos fármacos , Proto-Oncogene Mas , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Inibidores da Topoisomerase I/farmacologia , Topotecan/farmacologia , Proteínas Supressoras de Tumor/metabolismo
8.
PLoS One ; 8(3): e59879, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533654

RESUMO

Phosphoinositide 3-kinase (PI3K)/AKT/mammalian target of rapamycin inhibitor (mTOR) pathway is often constitutively activated in human tumor cells and thus has been considered as a promising drug target. To ascertain a therapeutical approach of nasopharyngeal carcinoma (NPC), we hypothesized NVP-BEZ235, a novel and potent imidazo[4,5-c] quinolone derivative, that dually inhibits both PI3K and mTOR kinases activities, had antitumor activity in NPC. Expectedly, we found that NVP-BEZ235 selectively inhibited proliferation of NPC cells rather than normal nasopharyngeal cells using MTT assay. In NPC cell lines, with the extended exposure, NVP-BEZ235 selectively inhibited proliferation of NPC cells harboring PIK3CA mutation, compared to cells with wild-type PIK3CA. Furthermore, exposure of NPC cells to NVP-BEZ235 resulted in G1 growth arrest by Propidium iodide uptake assay, reduction of cyclin D1and CDK4, and increased levels of P27 and P21 by Western blotting, but negligible apoptosis. Moreover, we found that cisplatin (CDDP) activated PI3K/AKT and mTORC1 pathways and NVP-BEZ235 alleviated the activation by CDDP through dually targeting PI3K and mTOR kinases. Also, NVP-BEZ235 combining with CDDP synergistically inhibited proliferation and induced apoptosis in NPC cells. In CNE2 and HONE1 nude mice xenograft models, orally NVP-BEZ235 efficiently attenuated tumor growth with no obvious toxicity. In combination with NVP-BEZ235 and CDDP, there was dramatic synergy in shrinking tumor volumes and inducing apoptosis through increasing Noxa, Bax and decreasing Mcl-1, Bcl-2. Based on the above results, NVP-BEZ235, which has entered phase I/II clinical trials in patients with advanced solid tumors, has a potential as a monotherapy or in combination with CDDP for NPC treatment.


Assuntos
Cisplatino/uso terapêutico , Imidazóis/uso terapêutico , Neoplasias Nasofaríngeas/tratamento farmacológico , Fosfatidilinositol 3-Quinases/metabolismo , Quinolinas/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Butadienos/farmacologia , Butadienos/uso terapêutico , Carcinoma , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Imidazóis/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/enzimologia , Neoplasias Nasofaríngeas/metabolismo , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Inibidores de Fosfoinositídeo-3 Quinase , Quinolinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Cell Signal ; 25(1): 150-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22982090

RESUMO

JNK signaling functions to induce defense mechanisms that protect organisms against a variety of different situations. The sestrin 2 gene, a p53-regulated member of the sestrins family, which lead to AMPK-dependent inhibition of TOR signaling, emerges as a novel player in autophagy induction. However, the relationship between JNK pathway, autophagy induction and sestrin 2 expression remains elusive. In the present study, we identify JNK as a regulator of autophagy in nasopharyngeal carcinoma cell lines CNE1 and CNE2 exposed to excisanin A or serum deprivation and demonstrate that activation of JNK can cause upregulation of sestrin 2 expression, which could be blocked by specific siRNAs directed against JNK1/2 or c-Jun. Chromatin immunoprecipitation and luciferase reporter analysis revealed that c-Jun was transcriptionally involved in the regulation of sestrin 2. Furthermore, knockdown of sestrin 2 by siRNAs similarly inhibited autophagy induction. Moreover, silencing the expression of autophagy related gene ATG5 or sestrin 2 significantly decreases cell death induced by excisanin A. Our results therefore identify JNK as a novel mediator of sestrin 2 expression, which plays a key role in autophagy induction following anticancer therapies in cancers.


Assuntos
Autofagia/efeitos dos fármacos , Diterpenos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Nucleares/metabolismo , Proteína 5 Relacionada à Autofagia , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Ativação Enzimática/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 8 Ativada por Mitógeno/genética , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 9 Ativada por Mitógeno/genética , Proteína Quinase 9 Ativada por Mitógeno/metabolismo , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/genética , Fosforilação , Proteínas Proto-Oncogênicas c-jun/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Regulação para Cima/efeitos dos fármacos
10.
PLoS One ; 7(9): e45058, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23024792

RESUMO

BACKGROUND: Topotecan produces DNA damage that induces autophagy in cancer cells. In this study, sensitising topotecan to colon cancer cells with different P53 status via modulation of autophagy was examined. METHODOLOGY/PRINCIPAL FINDINGS: The DNA damage induced by topotecan treatment resulted in cytoprotective autophagy in colon cancer cells with wild-type p53. However, in cells with mutant p53 or p53 knockout, treatment with topotecan induced autophagy-associated cell death. In wild-type p53 colon cancer cells, topotecan treatment activated p53, upregulated the expression of sestrin 2, induced the phosphorylation of the AMPKα subunit at Thr172, and inhibited the mTORC1 pathway. Furthermore, the inhibition of autophagy enhanced the anti-tumour effect of topotecan treatment in wild-type p53 colon cancer cells but alleviated the anti-tumour effect of topotecan treatment in p53 knockout cells in vivo. CONCLUSIONS/SIGNIFICANCE: These results imply that the wild-type p53-dependent induction of cytoprotective autophagy is one of the cellular responses that determines the cellular sensitivity to the DNA-damaging drug topotecan. Therefore, our study provides a potential therapeutic strategy that utilises a combination of DNA-damaging agents and autophagy inhibitors for the treatment of colon cancer with wild-type p53.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Neoplasias do Colo/genética , Mutação , Topotecan/farmacologia , Proteína Supressora de Tumor p53/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Técnicas de Inativação de Genes , Células HCT116 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Nus , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Chin J Cancer ; 30(10): 690-700, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21959046

RESUMO

Although the anti-malaria drug chloroquine (CQ) has been shown to enhance chemotherapy and radiation sensitivity in clinical trials, the potential mechanisms underlying this enhancement are still unclear. Here, we examined the relevant mechanisms by which the multipotent CQ enhanced the cytotoxicity of topotecan (TPT). The lung cancer cell line A549 was treated with TPT alone or TPT combined with CQ at non-cytotoxic concentrations. Cell viability was assessed using the MTT assay. The percentage of apoptotic cells and the presence of a side population of cells were both determined by flow cytometry. Autophagy and the expression of Bcl-2 family proteins were examined by Western blotting. The accumulation of YFP-LC3 dots and the formation of acidic vesicular organelles were examined by confocal microscopy. CQ sensitized A549 cells to TPT and enhanced TPT-induced apoptosis in a Bcl-2 family protein-independent fashion. CQ inhibited TPT-induced autophagy, which modified the cytotoxicity of TPT. However, CQ failed to modify the transfer of TPT across the cytoplasmic membrane and did not increase lysosomal permeability. This study showed that CQ at non-cytotoxic concentrations potentiated the cytotoxicity of TPT by interfering with autophagy, implying that CQ has significant potential as a chemotherapeutic enhancer.


Assuntos
Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Neoplasias Pulmonares/patologia , Topotecan/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Inibidores da Topoisomerase I/farmacologia , Proteína X Associada a bcl-2/metabolismo
12.
Cancer Sci ; 102(8): 1568-75, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21518141

RESUMO

The serine/threonine kinase UNC-51-like kinase 1 (ULK1) plays an essential role in autophagosome formation, although the exact molecular mechanism is unknown. The present study was first to investigate the clinical and prognostic significance of ULK1 in esophageal squamous cell carcinoma (ESCC). Protein and mRNA levels of ULK1 in normal esophageal epithelial cells, ESCC cell lines, paired ESCC lesions and the adjacent noncancerous tissues were examined using western blot and real-time RT-PCR. The results showed that only the ULK1 protein level was upregulated in ESCC samples compared with normal esophageal cells and tissues. Also, we found that protein stabilization of ULK1 was higher in ESCC cell lines. Furthermore, immunohistochemical staining of ULK1 was performed on the tissue microarray containing 248 ESCC and 51 normal esophageal tissues. A total of 70.2% ESCC specimens showed intensive expression of ULK1 in contrast to the undetectable expression of ULK1 in normal esophageal tissues. Statistical analysis revealed that ULK1 expression was significantly correlated with T status (P = 0.048). Moreover, patients with higher ULK1 expression were associated with shorter overall survival time. Multivariate analysis suggested that ULK1 expression and N status (P < 0.001) were independent prognostic indicators for the survival of patients. Functional studies showed that suppression of ULK1 expression in ESCC cell lines by specific small interfering RNA resulted in inhibition of cell proliferation and induction of apoptosis under starvation conditions. These findings provide evidence that ULK1 represents a novel and clinically useful biomarker for ESCC patients and plays an important role during the progression of ESCC.


Assuntos
Biomarcadores Tumorais/fisiologia , Carcinoma de Células Escamosas/enzimologia , Neoplasias Esofágicas/enzimologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Adulto , Idoso , Apoptose , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Esôfago/enzimologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/análise , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/análise
13.
Chin J Cancer ; 29(7): 655-60, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20591217

RESUMO

BACKGROUND AND OBJECTIVE: Hirsutanol A is a novel sesquiterpene compound purified from fungus chondrostereum sp in Sarcophyton tortuosum. Its pharmacologic effect has not been reported yet. This study aimed to investigate cytotoxic effect of Hirsutanol A on hepatocellular carcinoma (HCC) cells and its mechanism. METHODS: Hep3B cells were treated with different concentrations of Hirsutanol A. Cell proliferation was detected by MTT assay. The protein expression of LC3 was determined by Western blot. The generation of reactive oxygen species (ROS) was monitored by flow cytometry. RESULTS: Hirsutanol A significantly inhibited proliferation of Hep3B cells with 50% inhibition concentrations (IC50) of 14.54, 6.71, and 3.59 micromol/L when exposed to Hirsutanol A for 24, 48, and 72 h, respectively. Incubation of Hep3B cells with Hirsutanol A markedly increased the level of ROS and the autophagy marker MAP-LC3 conversion from type I to type II. Pre-incubation with an antioxidant N-acetyl cystein (NAC) decreased the level of ROS, and reduced MAP-LC3 I-II conversion, and suppressed cell death. Blocking autophagy with a specific autophagy inhibitor 3-methyladenine (3-MA), the cytotoxic effect of this compound was attenuated. CONCLUSION: Hirsutanol A has potent cytotoxic effect, and can induce autophagic cell death via increasing ROS production.


Assuntos
Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular , Morte Celular/efeitos dos fármacos , Neoplasias Hepáticas , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/farmacologia , Acetilcisteína/farmacologia , Adenina/análogos & derivados , Adenina/farmacologia , Agaricales/química , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/farmacologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Proteínas Associadas aos Microtúbulos/metabolismo , Sesquiterpenos/administração & dosagem , Sesquiterpenos/isolamento & purificação
14.
Cancer Biol Ther ; 8(8): 739-43, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19242112

RESUMO

ErbB-2 gene encodes tyrosine kinase receptor p185(neu). Overexpression of erbB-2 plays a key role in tumorigenesis or progression such as breast cancer and ovarian cancer. Our previous study showed that ON-III (2',4'-dihydroxy-6'-methoxy-3',5'-dimethylchalcone) extracted from Traditional Chinese Medicine Cleistocaly xoperculatus dry flower could inhibit KDR tyrosine kinase phosphorylation and tumor growth in vivo. In this study, we reported that ON-III repressed tyrosine phosphorylation of erbB-2 without reduced erbB-2 receptor expression in MDA-MB-453 cells. Activation of mitogen-activated protein kinase (MAPK) and AKT, downstream molecules of erbB-2-mediated signal transduction pathway, was inhibited following exposure to ON-III. ON-III induced apoptosis in breast cancer cells as determined by caspase-3 and PARP cleavage. Also, ON-III upregulated the expression of proapoptotic BH3-only Bcl-2 family member Bim. Bim siRNA could inhibit ON-III-mediated apoptosis in MDA-MB-453 cells. It concludes that ON-III inhibits erbB-2 tyrosine kinase phosphorylation, shuts down its downstream pathway and triggered apoptosis via induction of Bim. These results suggest that ON-III is a potential novel anti-cancer agent for erbB-2-overexpressing cancer.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Chalconas/farmacologia , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptor ErbB-2/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Proteína 11 Semelhante a Bcl-2 , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Proliferação de Células/efeitos dos fármacos , Humanos , Immunoblotting , Imunoprecipitação , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/farmacologia , Receptor ErbB-2/metabolismo , Células Tumorais Cultivadas
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