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1.
Artigo em Inglês | MEDLINE | ID: mdl-38802479

RESUMO

Environmental stimuli elicit drug craving and relapse in cocaine users by triggering the retrieval of strong cocaine-related contextual memories. Retrieval can also destabilize drug memories, requiring reconsolidation, a protein synthesis-dependent storage process, to maintain memory strength. Corticotropin-releasing factor (CRF) signaling in the basolateral amygdala (BLA) is necessary for cocaine-memory reconsolidation. We have hypothesized that a critical source of CRF in the BLA is the dorsal raphe nucleus (DR) based on its neurochemistry, anatomical connectivity, and requisite involvement in cocaine-memory reconsolidation. To test this hypothesis, male and female Sprague-Dawley rats received adeno-associated viruses to express Gi-coupled designer receptors exclusively activated by designer drugs (DREADDs) selectively in CRF neurons of the DR and injection cannulae directed at the BLA. The rats were trained to self-administer cocaine in a distinct environmental context then received extinction training in a different context. Next, they were briefly re-exposed to the cocaine-predictive context to destabilize (reactivate) cocaine memories. Intra-BLA infusions of the DREADD agonist deschloroclozapine (DCZ; 0.1 mM, 0.5 µL/hemisphere) immediately after memory reactivation attenuated cocaine-memory strength, relative to vehicle infusion. This was indicated by a selective, DCZ-induced and memory reactivation-dependent decrease in drug-seeking behavior in the cocaine-predictive context in DREADD-expressing males and females at test compared to respective controls. Notably, BLA-projecting DR CRF neurons that exhibited increased c-Fos expression during memory reconsolidation co-expressed the glutamatergic neuronal marker, vesicular glutamate transporter 3. Together, these findings suggest that the DRCRF → BLA circuit is engaged to maintain cocaine-memory strength after memory destabilization, and this phenomenon may be mediated by DR CRF and/or glutamate release in the BLA.

2.
bioRxiv ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38405858

RESUMO

Environmental stimuli elicit drug craving and relapse in cocaine users by triggering the retrieval of strong cocainerelated contextual memories. Retrieval can also destabilize drug memories, requiring reconsolidation, a protein synthesis-dependent storage process, to maintain memory strength. Corticotropin-releasing factor (CRF) signaling in the basolateral amygdala (BLA) is necessary for cocainememory reconsolidation. We have hypothesized that a critical source of CRF in the BLA is the dorsal raphe nucleus (DR) based on its neurochemistry, anatomical connectivity, and requisite involvement in cocaine-memory reconsolidation. To test this hypothesis, male and female Sprague-Dawley rats received adeno-associated viruses to express Gi-coupled designer receptors exclusively activated by designer drugs (DREADDs) selectively in CRF neurons of the DR and injection cannulae directed at the BLA. The rats were trained to self-administer cocaine in a distinct environmental context then received extinction training in a different context. They were then briefly reexposed to the cocaine-predictive context to destabilize (reactivate) cocaine memories. Intra-BLA infusions of the DREADD agonist deschloroclozapine (DCZ; 0.1 mM, 0.5 µL/hemisphere) after memory reactivation attenuated cocaine-memory strength, relative to vehicle infusion. This was indicated by a selective, DCZ-induced and memory reactivation-dependent decrease in drug-seeking behavior in the cocaine-predictive context in DREADD-expressing males and females at test compared to respective controls. Notably, BLA-projecting DR CRF neurons that exhibited increased c-Fos expression during memory reconsolidation co-expressed glutamatergic and serotonergic neuronal markers. Together, these findings suggest that the DRCRF → BLA circuit is engaged to maintain cocaine-memory strength after memory destabilization, and this phenomenon may be mediated by DR CRF, glutamate, and/or serotonin release in the BLA.

3.
Molecules ; 28(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38005335

RESUMO

To explore the complete biosynthesis process of flavonoid glycosides in safflower, specifically the key glycosyltransferase that might be involved, as well as to develop an efficient biocatalyst to synthesize flavonoid glycosides, a glycosyltransferase CtUGT4, with flavonoid-O-glycosyltransferase activity, was identified in safflower. The fusion protein of CtUGT4 was heterologously expressed in Escherichia coli, and the target protein was purified. The recombinant protein can catalyze quercetin to form quercetin-7-O-glucoside, and kaempferol to form kaempferol-3-O in vitro, and a series of flavones, flavonols, dihydroflavones, chalcones, and chalcone glycosides were used as substrates to generate new products. CtUGT4 was expressed in the tobacco transient expression system, and the enzyme activity results showed that it could catalyze kaempferol to kaempferol-3-O-glucoside, and quercetin to quercetin-3-O-glucoside. After overexpressing CtUGT4 in safflower, the content of quercetin-3-O-rutinoside in the safflower florets increased significantly, and the content of quercetin-3-O-glucoside also tended to increase, which preliminarily confirmed the function of CtUGT4 flavonoid-O-glycosyltransferase. This work demonstrated the flavonoid-O-glycosyltransferase function of safflower CtUGT4 and showed differences in the affinity for different flavonoid substrates and the regioselectivity of catalytic sites in safflower, both in vivo and in vitro, providing clues for further research regarding the function of UGT genes, as well as new ideas for the cultivation engineering of the directional improvement of effective metabolites in safflower.


Assuntos
Carthamus tinctorius , Quempferóis , Quempferóis/metabolismo , Quercetina/metabolismo , Carthamus tinctorius/genética , Carthamus tinctorius/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Flavonóis/metabolismo , Flavonoides/metabolismo , Glicosídeos/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
4.
Neuropsychopharmacology ; 47(8): 1473-1483, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35581381

RESUMO

The dorsal hippocampus (DH) is key to the maintenance of cocaine memories through reconsolidation into long-term memory stores after retrieval-induced memory destabilization. Here, we examined the time-dependent role of the cornu ammonis 3 DH subregion (dCA3) in cocaine-memory reconsolidation by utilizing the temporal and spatial specificity of optogenetics. eNpHR3.0-eYFP- or eYFP-expressing male Sprague-Dawley rats were trained to lever press for cocaine infusions in a distinct context and received extinction training in a different context. Rats were then re-exposed to the cocaine-paired context for 15 min to destabilize cocaine memories (memory reactivation) or remained in their home cages (no-reactivation). Optogenetic dCA3 inhibition for one hour immediately after memory reactivation reduced c-Fos expression (index of neuronal activation) in dCA3 stratum pyramidale (SP) glutamatergic and GABAergic neurons and in stratum lucidum (SL) GABAergic neurons during reconsolidation. Furthermore, dCA3 inhibition attenuated drug-seeking behavior (non-reinforced lever presses) selectively in the cocaine-paired context three days later (recall test), relative to no photoinhibition. This behavioral effect was eNpHR3.0-, memory-reactivation, and time-dependent, indicating a memory-reconsolidation deficit. Based on this observation and our previous finding that protein synthesis in the DH is not necessary for cocaine-memory reconsolidation, we postulate that recurrent pyramidal neuronal activity in the dCA3 may maintain labile cocaine memories prior to protein synthesis-dependent reconsolidation elsewhere, and SL/SP interneurons may facilitate this process by limiting extraneous neuronal activity. Interestingly, SL c-Fos expression was reduced at recall concomitant with impairment in cocaine-seeking behavior, suggesting that SL neurons may also facilitate cocaine-memory retrieval by inhibiting non-engram neuronal activity.


Assuntos
Cocaína , Animais , Cocaína/farmacologia , Extinção Psicológica , Hipocampo , Masculino , Optogenética , Ratos , Ratos Sprague-Dawley , Autoadministração
5.
Front Plant Sci ; 13: 833811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463446

RESUMO

The unique flavonoids, quinochalcones, such as hydroxysafflor yellow A (HSYA) and carthamin, in the floret of safflower showed an excellent pharmacological effect in treating cardiocerebral vascular disease, yet the regulating mechanisms governing the flavonoid biosynthesis are largely unknown. In this study, CtACO3, the key enzyme genes required for the ethylene signaling pathway, were found positively related to the flavonoid biosynthesis at different floret development periods in safflower and has two CtACO3 transcripts, CtACO3-1 and CtACO3-2, and the latter was a splice variant of CtACO3 that lacked 5' coding sequences. The functions and underlying probable mechanisms of the two transcripts have been explored. The quantitative PCR data showed that CtACO3-1 and CtACO3-2 were predominantly expressed in the floret and increased with floret development. Subcellular localization results indicated that CtACO3-1 was localized in the cytoplasm, whereas CtACO3-2 was localized in the cytoplasm and nucleus. Furthermore, the overexpression of CtACO3-1 or CtACO3-2 in transgenic safflower lines significantly increased the accumulation of quinochalcones and flavonols. The expression of the flavonoid pathway genes showed an upward trend, with CtCHS1, CtF3H1, CtFLS1, and CtDFR1 was considerably induced in the overexpression of CtACO3-1 or CtACO3-2 lines. An interesting phenomenon for CtACO3-2 protein suppressing the transcription of CtACO3-1 might be related to the nucleus location of CtACO3-2. Yeast two-hybrid (Y2H), glutathione S-transferase (GST) pull-down, and BiFC experiments revealed that CtACO3-2 interacted with CtCSN5a. In addition, the interactions between CtCSN5a and CtCOI1, CtCOI1 and CtJAZ1, CtJAZ1 and CtbHLH3 were observed by Y2H and GST pull-down methods, respectively. The above results suggested that the CtACO3-2 promoting flavonoid accumulation might be attributed to the transcriptional activation of flavonoid biosynthesis genes by CtbHLH3, whereas the CtbHLH3 might be regulated through CtCSN5-CtCOI1-CtJAZ1 signal molecules. Our study provided a novel insight of CtACO3 affected the flavonoid biosynthesis in safflower.

6.
Neuropharmacology ; 200: 108819, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610289

RESUMO

The basolateral amygdala (BLA) is a critical brain region for cocaine-memory reconsolidation. Corticotropin-releasing factor receptor type 1 (CRFR1) is densely expressed in the BLA, and CRFR1 stimulation can activate intra-cellular signaling cascades that mediate memory reconsolidation. Hence, we tested the hypothesis that BLA CRFR1 stimulation is necessary and sufficient for cocaine-memory reconsolidation. Using an instrumental model of drug relapse, male and female Sprague-Dawley rats received cocaine self-administration training in a distinct environmental context over 10 days followed by extinction training in a different context over 7 days. Next, rats were re-exposed to the cocaine-paired context for 15 min to initiate cocaine-memory retrieval and destabilization. Immediately or 6 h after this session, the rats received bilateral vehicle, antalarmin (CRFR1 antagonist; 500 ng/hemisphere), or corticotropin-releasing factor (CRF; 0.2, 30 or 500 ng/hemisphere) infusions into the BLA. Resulting changes in drug context-induced cocaine seeking (index of context-cocaine memory strength) were assessed three days later. Female rats self-administered more cocaine infusions and exhibited more extinction responding than males. Intra-BLA antalarmin treatment immediately after memory retrieval (i.e., when cocaine memories were labile), but not 6 h later (i.e., after memory reconsolidation), attenuated drug context-induced cocaine seeking at test independent of sex, relative to vehicle. Conversely, intra-BLA CRF treatment increased this behavior selectively in females, in a U-shaped dose-dependent fashion. In control experiments, a high (behaviorally ineffective) dose of CRF treatment did not reduce BLA CRFR1 cell-surface expression in females. Thus, BLA CRFR1 signaling is necessary and sufficient, in a sex-dependent manner, for regulating cocaine-memory strength.


Assuntos
Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína/patologia , Cocaína/farmacologia , Comportamento de Procura de Droga/efeitos dos fármacos , Memória/efeitos dos fármacos , Receptores de Hormônio Liberador da Corticotropina/efeitos dos fármacos , Animais , Hormônio Liberador da Corticotropina/farmacologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Pirimidinas/farmacologia , Pirróis/farmacologia , Ratos , Ratos Sprague-Dawley
7.
Cancer Manag Res ; 12: 11203-11209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33177871

RESUMO

AIM: To investigate the role of CAB39 in nasopharyngeal carcinoma (NPC) development and examine its expression level in NPC tumor samples. METHODS: Immunohistochemistry staining of NPC tissue microarray was conducted to detect the expression of CAB39 protein in NPC tissues, and the clinical significance of CAB39 was evaluated. Lentivirus-mediated over-expression of CAB39 was designed to increase CAB39 expression in CNE-1 cells. Cell colony formation, cell cycle and CCK-8 proliferation experiments were performed to compare the proliferation ability of CNE-1 cells with or without CAB39 over-expression. Western blotting was conducted to examine downstream targets of CAB39. RESULTS: CAB39 expression was higher in tumor samples compared to normal tissue and the higher CAB39 expression was positively correlated to higher TNM stage and distant metastasis rate and non-keratinized state. Further, CAB39 over-expression dramatically increased the proliferation and colony formation of CNE-1 cells. Finally, higher p-JNK protein level was found in CAB39 over-expressing cells. CONCLUSION: CAB39 promotes the proliferation of CNE-1 cells via up-regulating p-JNK.

8.
Oncol Lett ; 17(2): 1581-1588, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30675216

RESUMO

The aim of the present study was to discuss the design of a microfluidic chip consisting of columns, and its use for the enrichment of nasopharyngeal cancer (NPC) cells. A microfluidic chip experiment was simulated using FLUENT software. Within the microfluidic chip, aptamers were bound to the reaction chamber (consisting of columns) using a biotin-avidin system. Cell suspension was introduced into the reaction chamber to capture NPC cells. NPC cells were subsequently eluted, and the capture rate of the cells was calculated. The modified aptamer-bound microfluidic chip was able to capture NPC cells with a capture rate of ~90%. The modified aptamer-bound microfluidic chip has a wide range of potential applications for the diagnosis of NPC.

9.
Hepatology ; 60(5): 1659-73, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25042864

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) is a highly vascularized tumor with frequent extrahepatic metastasis. Active angiogenesis and metastasis are responsible for rapid recurrence and poor survival of HCC. However, the mechanisms that contribute to tumor metastasis remain unclear. Here we evaluate the effects of ATPase inhibitory factor 1 (IF1), an inhibitor of the mitochondrial H(+)-adenosine triphosphate (ATP) synthase, on HCC angiogenesis and metastasis. We found that increased expression of IF1 in human HCC predicts poor survival and disease recurrence after surgery. Patients with HCC who have large tumors, with vascular invasion and metastasis, expressed high levels of IF1. Invasive tumors overexpressing IF1 were featured by active epithelial-mesenchymal transition (EMT) and increased angiogenesis, whereas silencing IF1 expression attenuated EMT and invasion of HCC cells. Mechanistically, IF1 promoted Snai1 and vascular endothelial growth factor (VEGF) expression by way of activating nuclear factor kappa B (NF-κB) signaling, which depended on the binding of tumor necrosis factor (TNF) receptor-associated factor 1 (TRAF1) to NF-κB-inducing kinase (NIK) and the disruption of NIK association with the TRAF2-cIAP2 complex. Suppression of the NF-κB pathway interfered with IF1-mediated EMT and invasion. Chromatin immunoprecipitation assay showed that NF-κB can bind to the Snai1 promoter and trigger its transcription. IF1 was directly transcribed by NF-κB, thus forming a positive feedback signaling loop. There was a significant correlation between IF1 expression and pp65 levels in a cohort of HCC biopsies, and the combination of these two parameters was a more powerful predictor of poor prognosis. CONCLUSION: IF1 promotes HCC angiogenesis and metastasis by up-regulation of Snai1 and VEGF transcription, thereby providing new insight into HCC progression and IF1 function. (Hepatology 2014;60:1659-1673).


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , NF-kappa B/metabolismo , Neovascularização Patológica/metabolismo , Proteínas/metabolismo , Animais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , China/epidemiologia , Estudos de Coortes , Transição Epitelial-Mesenquimal , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/secundário , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Fosfoproteínas , Prognóstico , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Ativação Transcricional , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas da Matriz Viral , Proteína Inibidora de ATPase
10.
Mol Cancer ; 13: 133, 2014 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-24884809

RESUMO

BACKGROUND: Arsenic trioxide has been demonstrated as an effective anti-cancer drug against leukemia and solid tumors both in vitro and in vivo. However, recent phase II trials demonstrated that single agent arsenic trioxide was poorly effective against hepatocellular carcinoma (HCC), which might be due to drug resistance. METHODS: Mutation detection of p53 gene in arsenic trioxide resistant HCC cell lines was performed. The therapeutic effects of arsenic trioxide and Nutlin-3 on HCC were evaluated both in vitro and in vivo. A series of experiments including MTT, apoptosis assays, co-Immunoprecipitation, siRNA transfection, lentiviral infection, cell migration, invasion, and epithelial-mesenchy-mal transition (EMT) assays were performed to investigate the underlying mechanisms. RESULTS: The acquisition of p53 mutation contributed to arsenic trioxide resistance and enhanced metastatic potential of HCC cells. Mutant p53 (Mutp53) silence could re-sensitize HCC resistant cells to arsenic trioxide and inhibit the metastatic activities, while mutp53 overexpression showed the opposite effects. Neither arsenic trioxide nor Nutlin-3 could exhibit obvious effects against arsenic trioxide resistant HCC cells, while combination of them showed significant effects. Nutlin-3 can not only increase the intracellular arsenicals through inhibition of p-gp but also promote the p73 activation and mutp53 degradation mediated by arsenic trioxide. In vivo experiments indicated that Nutlin-3 can potentiate the antitumor activities of arsenic trioxide in an orthotopic hepatic tumor model and inhibit the metastasis to lung. CONCLUSIONS: Acquisitions of p53 mutations contributed to the resistance of HCC to arsenic trioxide. Nutlin-3 could overcome arsenic trioxide resistance and inhibit tumor metastasis through p73 activation and promoting mutant p53 degradation mediated by arsenic trioxide.


Assuntos
Antineoplásicos/farmacologia , Arsenicais/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Imidazóis/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Óxidos/farmacologia , Piperazinas/farmacologia , Proteína Supressora de Tumor p53/genética , Animais , Trióxido de Arsênio , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Mutação , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Transdução de Sinais , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
11.
Hepatology ; 59(3): 935-46, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24037855

RESUMO

UNLABELLED: Although gankyrin is involved in the tumorigenicity and metastasis of some malignancies, the role of gankyrin in cholangiocarcinoma (CCA) is unclear. In this study we investigated the expression of gankyrin in human CCA tissues and cell lines. The effects of gankyrin on CCA tumor growth and metastasis were determined both in vivo and in vitro. The results showed that gankyrin was overexpressed in CCA tissues and cell lines. Gankyrin expression was associated with CCA histological differentiation, TNM stage, and metastasis. The multivariate Cox analysis revealed that gankyrin was an independent prognostic indicator for overall survival. Gankyrin overexpression promoted CCA cell proliferation, migration, and invasion, while gankyrin knockdown inhibited CCA tumor growth, metastasis, and induced Rb-dependent senescence and G1 phase cell cycle arrest. Gankyrin increased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and promoted the nuclear translocation of p-STAT3. Suppression of STAT3 signaling by small interfering RNA (siRNA) or STAT3 inhibitor interfered with gankyrin-mediated carcinogenesis and metastasis, while interleukin (IL)-6, a known upstream activator of STAT3, could restore the proliferation and migration of gankyrin-silenced CCA cells. The IL-6 level was decreased by gankyrin knockdown, while increased by gankyrin overexpression. Gankyrin regulated IL-6 expression by way of facilitating the phosphorylation of Rb; meanwhile, rIL-6 treatment increased the expression of gankyrin, suggesting that IL-6 was regulated by a positive feedback loop involving gankyrin in CCA. In the xenograft experiments, gankyrin overexpression accelerated tumor formation and increased tumor weight, whereas gankyrin knockdown showed the opposite effects. The in vivo spontaneous metastasis assay revealed that gankyrin promoted CCA metastasis through IL-6/STAT3 signaling pathway. CONCLUSION: Gankyrin is crucial for CCA carcinogenesis and metastasis by activating IL-6/STAT3 signaling pathway through down-regulating Rb protein.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Ductos Biliares Intra-Hepáticos/metabolismo , Colangiocarcinoma/metabolismo , Interleucina-6/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Pontos de Checagem do Ciclo Celular/fisiologia , Movimento Celular/fisiologia , Colangiocarcinoma/genética , Colangiocarcinoma/secundário , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica/patologia , Valor Preditivo dos Testes , Prognóstico , Complexo de Endopeptidases do Proteassoma/genética , Proteínas Proto-Oncogênicas/genética , Proteína do Retinoblastoma/metabolismo , Transdução de Sinais/fisiologia
12.
Gut ; 63(10): 1635-47, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24352616

RESUMO

BACKGROUND: Mounting epidemiological evidence supports a role for phosphatase and tensin homologue (PTEN)-T cell leukaemia 1 (Tcl1) signalling deregulation in hepatocarcinogenesis. OBJECTIVE: To determine the molecular and biochemical mechanisms by which the PTEN/Tcl1 axis regulates the pentose phosphate pathway (PPP) in hepatocellular carcinoma (HCC). METHODS: We compared levels of PTEN and glucose-6-phosphate dehydrogenase (G6PD) mRNA in human HCC and healthy liver tissue. We measured PPP flux, glucose consumption, lactate production, nicotinamide adenine dinucleotide phosphate (NADPH) levels and lipid accumulation. We investigated the PTEN/Tcl1 axis using molecular biology, biochemistry and mass spectrometry analysis. We assessed proliferation, apoptosis and senescence in cultured cells, and tumour formation in mice. RESULTS: We showed that PTEN inhibited the PPP pathway in human liver tumours. Through the PPP, PTEN suppressed glucose consumption and biosynthesis. Mechanistically, the PTEN protein bound to G6PD, the first and rate-limiting enzyme of the PPP and prevented the formation of the active G6PD dimer. Tcl1, a coactivator for Akt, reversed the effects of PTEN on biosynthesis. Tcl1 promoted G6PD activity and also increased G6PD pre-mRNA splicing and protein expression in a heterogeneous nuclear ribonucleoprotein (hnRNPK)-dependent manner. PTEN also formed a complex with hnRNPK, which inhibited G6PD pre-mRNA splicing. Moreover, PTEN inactivated Tcl1 via glycogen synthase kinase-3ß (GSK3ß)-mediated phosphorylation. Importantly, Tcl1 knockdown enhanced the sensitivity of HCC to sorafenib, whereas G6PD knockdown inhibited hepatocarcinogenesis. CONCLUSIONS: These results establish the counteraction between PTEN and Tcl1 as a key mechanism that regulates the PPP and suggest that targeting the PTEN/Tcl1/hnRNPK/G6PD axis could open up possibilities for therapeutic intervention and improve the prognosis of patients with HCC.


Assuntos
Carcinoma Hepatocelular/genética , Glucosefosfato Desidrogenase/genética , Neoplasias Hepáticas Experimentais/genética , PTEN Fosfo-Hidrolase/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Precursores de RNA/genética , Splicing de RNA , Ribonucleoproteínas/metabolismo , Animais , Carcinoma Hepatocelular/metabolismo , Glucose/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Glicogênio Sintase/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo K , Humanos , Neoplasias Hepáticas Experimentais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Via de Pentose Fosfato/fisiologia , Fosforilação
13.
World J Gastroenterol ; 9(4): 683-7, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12679910

RESUMO

AIM: To investigate the global gene expression of cancer related genes in hepatoma cell line HLE using Atlas Human Cancer Array membranes with 588 well-characterized human genes related with cancer and tumor biology. METHODS: Hybridization of cDNA blotting membrane was performed with (32)P-labeled cDNA probes synthesized from RNA isolated from Human hepatoma cell line HLE and non-cirrhotic normal liver which was liver transplantation donor. AtlasImage, a software specific to array, was used to analyze the result. The expression pattern of some genes identified by Atlas arrays hybridization was confirmed by reverse transcription polymerase chain reaction (RT-PCR) in 24 pairs of specimens and Northern blot of 4 pairs of specimens. RESULTS: The differential expression of cell cycle/growth regulator in hepatocellular carcinoma (HCC) showed a stronger tendency toward cell proliferation with more than 1.5-fold up-regulation of Cyclin C, ERK5, ERK6, E2F-3, TFDP-2 and CK4. The anti-apoptotic factors such as Akt-1 were up-regulated, whereas the promotive genes of apoptosis such as ABL2 were down-regulated. Among oncogene/tumors suppressors, SKY was down-regulated. Some genes such as Integrin beta 8, Integrin beta 7, DNA-PK, CSPCP, byglycan, Tenacin and DNA Topo were up-regulated. A number of genes, including LAR, MEK1, eps15, TDGF1, ARHGDIA were down-regulated. In general, expression of the cancer progression genes was up-regulated, while expression of anti-cancer progression genes was down-regulated. These differentially expressed genes tested with RT-PCR were in consistent with cDNA array findings. CONCLUSION: Investigation of these genes in HCC is helpful in disclosing molecular mechanism of pathogenesis and progression of HCC. For the first time few genes were discovered in HCC. Further study is required for the precise relationship between the altered genes and their correlation with the pathogenesis of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Neoplasias Hepáticas/genética , Sequência de Bases , Ciclo Celular/genética , Divisão Celular/genética , Ciclinas/genética , Primers do DNA , DNA Complementar/genética , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
14.
World J Gastroenterol ; 9(1): 188-91, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12508380

RESUMO

AIM: To investigate the utility of K-ras mutation analysis of ultrasound guided fine-needle aspirate biopsy of pancreatic masses. METHODS: Sixty-six ultrasound guided fine-needle biopsies were evaluated by cytology, histology and k-ras mutation. The mutation at codon 12 of the k-ras oncogene was detected by artificial restriction fragment length polymorphisms using Bst NI approach. RESULTS: The presence of malignant cells was reported in 40 of 54 pancreatic carcinomas and K-ras mutations were detected in 45 of the 54 FNABs of pancreatic carcinomas. The sensitivity of cytology and k-ras mutation were 74 % and 83 %, respectively. The specialty of cytology and k-ras mutation were both 100 %. The sensitivity and specialty of k-ras mutation combined with cytology were 83 % and 100 %, respectively. CONCLUSION: High diagnostic accuracy with acceptable discomfort of FNAB make it useful in diagnosis of pancreatic carcinoma. Ultrasound guided fine-needle biopsy is a safe and feasible method for diagnosing pancreatic cancer. Pancreatic carcinoma has the highest K-ras mutation rate among all solid tumors. The mutation rate of k-ras is about 80-100 %. The usage of mutation of codon 12 of k-ras oncogene combined with cytology is a good alternative for evaluation of pancreatic masses.


Assuntos
Biópsia por Agulha/métodos , Genes ras , Mutação , Pâncreas , Neoplasias Pancreáticas/diagnóstico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Pâncreas/cirurgia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Ultrassonografia
15.
World J Gastroenterol ; 8(4): 624-30, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12174368

RESUMO

AIM: To study local therapeutic efficacy, side effects, and complications of radiofrequency ablation (RFA), which is emerging as a new method for the treatment of patients with hepatocellular carcinoma (HCC) with cirrhosis or chronic hepatitis and metastatic liver cancer. METHODS: Thirty-six patients with primary and secondary liver cancers (21 with primary hepatocellular carcinoma, 12 with colorectal cancer liver metastases and 3 with other malignant liver metastases), which were considered not suitable for curative resection, were include in this study. They were treated either with RFA (RITA2000, Mountain View, California, USA) percutaneously (n=20) or intraoperatively (n=16).The procedures were performed using the ultrasound guidance. The quality of RFA were based on monitoring of equipments and subject feeling of the practitioners. Patients treated with RFA was followed according to clinical findings,radiographic images, and tumor markers. RESULTS: Thirty-six patients underwent RFA for 48 nodules. RFA was used to treat an average 1.3 lesions per patient, and the median size of treated lesions was 2.5 cm (range, 0.5-9 cm). The average hospital stay was 5.6 days overall (2.8 days for percutaneous cases and 7.9 days for open operations). Seven patients underwent a second RFA procedure (sequential ablations). Sixteen HCC patients with a high level of alpha fetoprotein (AFP) and 9 colorectal cancer liver metastases patients with a high level of serum carcinoembryonic antigen (CEA) have a great reduction benefited from RFA. Four (11.1 %) patients had complications: one skin burn; one postoperative hemorrhage; one cholecystitis and one hepatic abscess associated with percutaneous ablations of a large lesion. There were 4 deaths: 3 patients died from local and system diseases (1 at 7 month, 1 at 9 month, and 1 at 12 month), 1 patients died from cardiovascular shock, but no RFA-related death. At a median follow-up of 10 months (range, 1-24 months), 6 patients (16.7 %) had recurrences at an RFA site, and 20 patients (56.7 %) remained clinically free of disease. CONCLUSION: RF ablation appears to be an effective, safe, and relatively simple procedure for the treatment of unresectable liver cancers. The rate and severity of complications appear acceptable. However, further study is necessary to assess combination with other therapies, long-term recurrence rates and effect on overall survival.


Assuntos
Ablação por Cateter , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/efeitos adversos , Neoplasias Colorretais , Feminino , Humanos , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade
16.
World J Gastroenterol ; 8(4): 663-7, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12174375

RESUMO

AIM: Regional chemotherapy using hepatic artery catheters is a good method of treating patients with colorectal cancer liver metastases. We investigated the survival of patients with liver metastases from colorectal cancer using 5-fluorouracil (5-FU) and mitomycin C Cthrough implantable hepatic arterial infusion port. METHODS: Seventy-five patients with inoperable liver metastases from colorectal cancer were included between March, 1992 and November, 2001. We placed implantable hepatic arterial catheter (HAC) port by laparotomy. 5-FU, 1 000 mg/ m(2)/d continuous infusion for five days every four weeks, was delivered in the hepatic arterial catheter through the port. Mitomycin C, 30 mg/m(2)/d infusion in the first day every cycle through the port. Response to the treatment was evaluated by serial determinations of plasma CEA and imaging techniques consisting of computerized tomography and sonography of liver. RESULTS: Sixty-eight were performed hepatic artery chemotherapy and fifty-six were followed up among seventy-five HAC patients. Twenty-six patients(46.4 %) have responded and 4 complete remission were achieved. Eight patients (14.3 %) had stable liver metastases. Twenty-two patients (39.3 %) were progressed with increased tumor size and number. Twenty-nine patients(51.8%) had a decreased serum CEA level, while 10 patients (17.9 %) were stable and 17 patients (30.4 %) had an increased serum CEA level. There were no operative death in this series. Complications, which occurred in 18 patients (32.1 %), were as followed: hepatic artery thrombosis in 11, Upper gastric and intestinal bleeding in 3, liver abscess in 1, pocket infection in 1, cholangitis in 1, and hepatic artery pseudo-aneurysm in one patient. CONCLUSION: Combined infusion of 5-FU and mitomycin C by hepatic artery catheter port is an effective treatment for liver metastases from colorectal cancer. The high response and lower complication rates prove the adjuvant treatment of colorectal cancer with this treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Adulto , Idoso , Feminino , Fluoruracila/administração & dosagem , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem
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