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1.
Trials ; 20(1): 658, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31779696

RESUMO

BACKGROUND: First-episode psychosis (FEP) may lead to a progressive, potentially disabling and lifelong chronic illness; however, evidence suggests that the illness course can be improved if appropriate treatments are given at the early stages. Nonetheless, the efficacy of antipsychotic medications is suboptimal, particularly for negative and cognitive symptoms, and more efficacious and benign treatments are needed. Previous studies have shown that the antioxidant amino acid N-acetylcysteine (NAC) reduces negative symptoms and improves functioning in chronic schizophrenia and bipolar disorder. Research is scarce as to whether NAC is beneficial earlier in the course of illness. The primary aim of this study is to determine the efficacy of treatment with adjunctive NAC (2 g/day for 26 weeks) compared with placebo to improve psychiatric symptoms in young people experiencing FEP. Secondary aims are to explore the neurobiological mechanisms underpinning NAC and how they relate to various clinical and functional outcomes at 26- and 52-week follow-ups. METHODS/DESIGN: ENACT is a 26-week, randomised controlled trial of adjunctive NAC versus placebo, with a 26-week non-treatment follow-up period, for FEP. We will be recruiting 162 young people aged 15-25 years who have recently presented to, and are being treated at, the Early Psychosis Prevention and Intervention Centre, Melbourne, Australia. The primary outcome is the Total Score on the Positive and Negative Syndrome Scale which will be administered at baseline, and weeks 4, 8, 12, 26 (primary endpoint), and 52 (end of study). Secondary outcomes include: symptomatology, functioning, quality of life, neurocognition, blood-derived measures of: inflammation, oxidative and nitrosative stress, and magnetic resonance spectroscopy measures of glutathione concentration. DISCUSSION: Targeted drug development for FEP to date has generally not involved the exploration of neuroprotective agents. This study has the potential to offer a new, safe, and efficacious treatment for people with FEP, leading to better treatment outcomes. Additionally, the neuroprotective dimension of this study may lead to a better long-term prognosis for people with FEP. It has the potential to uncover a novel treatment that targets the neurobiological mechanisms of FEP and, if successful, will be a major advance for psychiatry. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ID: ACTRN12618000413224. Registered on 21 March 2018.


Assuntos
Acetilcisteína/uso terapêutico , Transtornos Psicóticos/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Acetilcisteína/efeitos adversos , Adolescente , Adulto , Humanos , Avaliação de Resultados em Cuidados de Saúde , Transtornos Psicóticos/psicologia , Qualidade de Vida , Adulto Jovem
2.
Psychol Med ; 48(10): 1592-1607, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29173201

RESUMO

BACKGROUND: Previous reviews suggest there is minimal evidence for an association between duration of untreated psychosis (DUP) and neurocognition. This is based on tallied findings of studies with small samples and neurocognition viewed as a single construct. We aimed to conduct a systematic review and meta-analysis examining the association between DUP and individual neurocognitive domains and tests in first-episode psychosis (FEP). METHOD: MOOSE and PRISMA guidelines were followed. Forty-three studies involving 4647 FEP patients were included. For studies providing correlations between DUP and neurocognition, 12 separate meta-analyses were performed based on neurocognitive domains/indices. The influence of demographic/clinical variables was tested using weighted linear meta-regression analyses. RESULTS: The relationship between DUP and most neurocognitive domains/indices was not significant. Longer DUP was associated with a larger cognitive deterioration index, i.e. current minus premorbid intellectual functioning (N = 4; mean ES -0.213, 95% confidence interval (CI) (-0.344 to -0.074), p = 0.003). Findings were homogeneous, with no evidence of publication bias or significant influence from moderators. For studies providing mean and standard deviations for neurocognitive measures and DUP, 20 meta-regressions were performed on individual neurocognitive tests. One significant finding emerged showing that longer DUP was associated with fewer Wisconsin Card Sorting Test-perseverative errors (mean ES -0.031, 95% CI (-0.048 to -0.013), p < 0.001). Exploratory meta-regressions in studies with mean DUP <360 days showed longer DUP was significantly associated with poorer performance on Trail Making Test A and B and higher Full-Scale IQ. CONCLUSION: There may not be a generalised association between DUP and neurocognition, however, specific cognitive functions may be associated with longer DUP or delayed help-seeking.


Assuntos
Disfunção Cognitiva/fisiopatologia , Comorbidade , Transtornos Psicóticos/fisiopatologia , Disfunção Cognitiva/epidemiologia , Humanos , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/terapia , Fatores de Tempo
3.
Psychol Med ; 48(1): 132-141, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28625185

RESUMO

BACKGROUND: Cognitive deficits are a core feature of schizophrenia, and impairments in most domains are thought to be stable over the course of the illness. However, cross-sectional evidence indicates that some areas of cognition, such as visuospatial associative memory, may be preserved in the early stages of psychosis, but become impaired in later established illness stages. This longitudinal study investigated change in visuospatial and verbal associative memory following psychosis onset. METHODS: In total 95 first-episode psychosis (FEP) patients and 63 healthy controls (HC) were assessed on neuropsychological tests at baseline, with 38 FEP and 22 HCs returning for follow-up assessment at 5-11 years. Visuospatial associative memory was assessed using the Cambridge Neuropsychological Test Automated Battery Visuospatial Paired-Associate Learning task, and verbal associative memory was assessed using Verbal Paired Associates subtest of the Wechsler Memory Scale - Revised. RESULTS: Visuospatial and verbal associative memory at baseline did not differ significantly between FEP patients and HCs. However, over follow-up, visuospatial associative memory deteriorated significantly for the FEP group, relative to healthy individuals. Conversely, verbal associative memory improved to a similar degree observed in HCs. In the FEP cohort, visuospatial (but not verbal) associative memory ability at baseline was associated with functional outcome at follow-up. CONCLUSIONS: Areas of cognition that develop prior to psychosis onset, such as visuospatial and verbal associative memory, may be preserved early in the illness. Later deterioration in visuospatial memory ability may relate to progressive structural and functional brain abnormalities that occurs following psychosis onset.


Assuntos
Cognição , Transtornos Psicóticos/psicologia , Esquizofrenia/fisiopatologia , Memória Espacial , Adolescente , Adulto , Austrália , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Análise de Regressão , Percepção Visual , Adulto Jovem
4.
Oncogene ; 36(18): 2599-2608, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-27941886

RESUMO

c-Jun N-terminal kinase (JNK) plays a vital role in malignant transformation of different cancers, and JNK is highly activated in basal-like triple-negative breast cancer (TNBC). However, the roles of JNK in regulating cancer stem-like cell (CSC) phenotype and tumorigenesis in TNBC are not well defined. JNK is known to mediate many cellular events via activating c-Jun. Here, we found that JNK regulated c-Jun activation in TNBC cells and that JNK activation correlated with c-Jun activation in TNBC tumors. Furthermore, the expression level of c-Jun was significantly higher in TNBC tumors than in non-TNBC tumors, and high c-Jun mRNA level was associated with shorter disease-free survival of patients with TNBC. Thus, we hypothesized that the JNK/c-Jun signaling pathway contributes to TNBC tumorigenesis. We found that knockdown of JNK1 or JNK2 or treatment with JNK-IN-8, an adenosine triphosphate-competitive irreversible pan-JNK inhibitor, significantly reduced cell proliferation, the ALDH1+ and CD44+/CD24- CSC subpopulations, and mammosphere formation, indicating that JNK promotes CSC self-renewal and maintenance in TNBC. We further demonstrated that both JNK1 and JNK2 regulated Notch1 transcription via activation of c-Jun and that the JNK/c-Jun signaling pathway promoted CSC phenotype through Notch1 signaling in TNBC. In a TNBC xenograft mouse model, JNK-IN-8 significantly suppressed tumor growth in a dose-dependent manner by inhibiting acquisition of the CSC phenotype. Taken together, our data demonstrate that JNK regulates TNBC tumorigenesis by promoting CSC phenotype through Notch1 signaling via activation of c-Jun and indicate that JNK/c-Jun/Notch1 signaling is a potential therapeutic target for TNBC.


Assuntos
Carcinogênese/genética , Proteínas Quinases JNK Ativadas por Mitógeno/genética , MAP Quinase Quinase 4/genética , Receptor Notch1/biossíntese , Neoplasias de Mama Triplo Negativas/genética , Animais , Linhagem Celular Tumoral , Linhagem da Célula/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Células-Tronco Neoplásicas/patologia , Fenótipo , Receptor Notch1/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Psychol Med ; 46(2): 253-64, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26456502

RESUMO

BACKGROUND: Theory of mind (ToM) dysfunction is prominent in a number of psychiatric disorders, in particular, autism and schizophrenia, and can play a significant role in poor functioning. There is now emerging evidence suggesting that ToM abilities are also impaired in bipolar disorder (BP); however, the relationship between ToM deficits and mood state is not clear. METHOD: We conducted a meta-analysis of ToM studies in BP. Thirty-four studies comparing 1214 patients with BP and 1097 healthy controls were included. BP groups included remitted (18 samples, 545 BP patients), subsyndromal (12 samples, 510 BP patients), and acute (manic and/or depressed) (10 samples, 159 BP patients) patients. RESULTS: ToM performance was significantly impaired in BP compared to controls. This impairment was evident across different types of ToM tasks (including affective/cognitive and verbal/visual) and was also evident in strictly euthymic patients with BP (d = 0.50). There were no significant differences between remitted and subsyndromal samples. However, ToM deficit was significantly more severe during acute episodes (d = 1.23). ToM impairment was significantly associated with neurocognitive and particularly with manic symptoms. CONCLUSION: Significant but modest sized ToM dysfunction is evident in remitted and subsyndromal BP. Acute episodes are associated with more robust ToM deficits. Exacerbation of ToM deficits may contribute to the more significant interpersonal problems observed in patients with acute or subsyndromal manic symptoms. There is a need for longitudinal studies comparing the developmental trajectory of ToM deficits across the course of the illness.


Assuntos
Transtorno Bipolar/psicologia , Teoria da Mente , Humanos
6.
Oncogene ; 33(4): 440-8, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-23376849

RESUMO

Intratumoral heterogeneity within individual breast tumors is a well-known phenomenon that may contribute to drug resistance. This heterogeneity is dependent on several factors, such as types of oncogenic drivers and tumor precursor cells. The purpose of our study was to engineer a mouse mammary tumor model with intratumoral heterogeneity by using defined genetic perturbations. To achieve this, we used mice with knockout (-/-) of Ink4a/Arf, a tumor suppressor locus; these mice are known to be susceptible to non-mammary tumors such as fibrosarcoma. To induce mammary tumors, we retrovirally introduced an oncogene, HRAS(G12V), into Ink4a/Arf(-/-) mammary cells in vitro, and those cells were inoculated into syngeneic mice mammary fat pads. We observed 100% tumorigenesis. The tumors formed were negative for estrogen receptor, progesterone receptor and HER2. Further, they had pathological features similar to those of human triple-negative breast cancer (TNBC) (for example, pushing borders, central necrosis). The tumors were found to be heterogeneous and included two subpopulations: CD49f(-) quiescent cells and CD49f(+)cells. Contrary to our expectation, CD49f(-) quiescent cells had high tumor-initiating potential and CD49f(+)cells had relatively low tumor-initiating potential. Gene expression analysis revealed that CD49f(-) quiescent cells overexpressed epithelial-to-mesenchymal transition-driving genes, reminiscent of tumor-initiating cells and claudin-low breast cancer. Our animal model with intratumoral heterogeneity, derived from defined genetic perturbations, allows us to test novel molecular targeted drugs in a setting that mimics the intratumoral heterogeneity of human TNBC.


Assuntos
Transformação Celular Neoplásica/genética , Integrina alfa6/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Animais , Transformação Celular Neoplásica/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/genética , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neoplásicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Proto-Oncogênicas p21(ras)/genética , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
7.
Oncogenesis ; 1: e22, 2012 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-23552738

RESUMO

Ovarian cancer is a major cause of death among women; there remains an urgent need to develop new effective therapies to target this cancer. Phosphoprotein enriched in astrocytes (PEA-15) is a 15-kDa phosphoprotein that is known to bind ERK1/2, thus blocking cell proliferation. The physiological activity of PEA-15 is dependent on the phosphorylation status of serine 104 (Ser104) and Ser116. However, little is known about the impact of PEA-15 phosphorylation on tumor progression. We have previously shown that overexpression of PEA-15 has an antitumor effect against both breast and ovarian cancer cells. Here, we report that using a human ovarian cancer tissue microarray, we found that tissues from patients with ovarian cancer were significantly more likely than adjacent normal tissues to express PEA-15 phosphorylated at both sites. Using phosphomimetic and nonphosphorylatable mutants of PEA-15, we found that mutant double-unphosphorylated PEA-15 in which Ser104 and Ser116 were substituted with alanine (PEA-15-AA) had a more potent antitumorigenic effect in ovarian cancer than did phosphomimetic PEA-15 in which Ser104 and Ser116 were substituted with aspartic acid (PEA-15-DD). Further, we observed that the antitumorigenic effect of PEA-15-AA was a result of inhibition of the migration capacity of cells and inhibition of in vivo angiogenesis. This inhibition was partially dependent on inhibition of ß-catenin expression and nuclear translocalization. Taken together, our results suggest that phosphorylated PEA-15 is an important contributor to the aggressiveness of ovarian cancer and justify the development of PEA-15-AA as an effective therapeutic molecule in the treatment of ovarian cancer.

9.
Acta Neuropsychiatr ; 18(6): 258-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27397205
10.
Oncogene ; 25(1): 79-90, 2006 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-16170361

RESUMO

The adenovirus type 5 gene E1A is known to suppress tumorigenicity by transcriptionally downregulating HER-2/neu (HER2) or by inducing apoptosis. We show here that E1A also suppressed the tumorigenicity of the low-HER2-expressing ovarian cancer cell line OVCAR-3 by decreasing cell proliferation. We further found that the mechanism responsible for this reduced proliferation is the presence of PEA15 (phosphoprotein enriched in astrocytes), which is upregulated by E1A in ovarian cancer; PEA15 promotes translocation of ERK from the nucleus to the cytoplasm, leading to inhibition of ERK-dependent transcription and proliferation. Indeed, siRNA-mediated knockdown of PEA15 expression in OVCAR-3 stable E1A transfectants resulted in a nuclear accumulation of the active form of ERK, followed by an increase in Elk-1 activity, DNA synthesis, and anchorage-independent growth. Finally, PEA15 by itself suppressed colony formation in breast and ovarian cancer cell lines, in which E1A is known to have antitumor activity. We conclude that part of the antitumor effect of E1A in ovarian cancer results from cytoplasmic sequestration of the activated form of ERK by PEA15.


Assuntos
Proteínas E1A de Adenovirus/metabolismo , Apoptose , Citoplasma/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/tratamento farmacológico , Fosfoproteínas/metabolismo , Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose , Western Blotting , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , DNA/metabolismo , Regulação para Baixo , Ativação Enzimática , Feminino , Vetores Genéticos/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Microscopia de Fluorescência , Neoplasias Ovarianas/metabolismo , RNA Interferente Pequeno/metabolismo , Receptor ErbB-2/metabolismo , Fatores de Tempo , Transcrição Gênica , Transfecção , Regulação para Cima
11.
Cancer Gene Ther ; 13(5): 451-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16294215

RESUMO

Radiation-induced apoptosis is thought to underlie the toxicity of radiation to normal tissues as well as to cancer cells. We hypothesized that specific ectopic overexpression of the antiapoptotic molecule Bcl-2 in normal cells would inhibit radiation-induced apoptosis and thereby reduce radiation-induced toxicity in normal cells. To express Bcl-2 specifically in normal cells (which have wild-type (wt) p53) but not in cancer cells (which often have mutated p53), we constructed a Bcl-2 expression plasmid (PG13-Bcl-2) with a minimal promoter regulated by multiple wt p53 DNA-binding sites and found that the presence of wt p53 protein strongly upregulated Bcl-2 expression through this plasmid. Transfection of NIH 3T3 fibroblasts, which express wt p53, with PG13-Bcl-2 increased cell survival and reduced apoptosis; however, transfection of MDA-MB-231 breast cancer cells, which have mutated p53, did not affect survival and apoptosis of those cells. These results indicate that irradiation of normal cells rapidly upregulates the expression of wt p53, which binds to the p53 binding sequence of the PG13-Bcl-2 plasmid and increases the transcriptional activity of Bcl-2. Ectopic expression of Bcl-2 reduced radiation-induced apoptosis only in normal cells (not in cancer cells). Bcl-2 expression was detected in the lung from mice injected via a tail vein with LPD-PG13-Bcl-2 or LPD-CMV-Bcl-2, but did not in the lung from mice treated with DOTAP or LPD-PG13-mock. This novel approach to inhibiting radiation-induced apoptosis in normal cells may allow such cells to be protected from radiation-induced toxicity. Further preclinical in vivo studies are needed.


Assuntos
Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Lesões por Radiação/prevenção & controle , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/genética , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Humanos , Pulmão/química , Pulmão/citologia , Pulmão/efeitos da radiação , Camundongos , Camundongos Endogâmicos , Células NIH 3T3 , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/genética , Lesões por Radiação/genética , Lesões por Radiação/metabolismo , Ativação Transcricional , Proteína Supressora de Tumor p53/genética , Regulação para Cima
12.
Hum Psychopharmacol ; 19(7): 503-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15378678

RESUMO

Impairments in early information processing are a hallmark feature of diverse neuropsychiatric disorders including schizophrenia and Alzheimer's disease (AD). Several lines of evidence implicate a dysfunction of the cholinergic system in these disorders, particularly in AD where there is known degeneration in major cholinergic pathways. Inspection time (IT), a measure of early visual information processing speed, has been shown to be sensitive to cholinergic manipulation. The current study employed the IT task to (1) examine the independent roles of nicotinic and muscarinic receptors in modulating information processing and (2) investigate the interaction of nicotinic and muscarinic receptor systems in modulating information processing. Twelve healthy participants completed a randomized, double-blind, placebo-controlled study under four drug conditions; (1) placebo, (2) mecamylamine (15 mg; oral), (3) scopolamine (0.4 mg, s.c.), (4) mecamylamine (15 mg) + scopolamine (0.4 mg). IT measures were examined at baseline and 2.5 h post drug administration. Selective blockade of nicotinic receptors with mecamylamine did not significantly impair IT, whereas selective blockade of muscarinic receptors with scopolamine produced a significant but small impairment in IT. Combined blockade of both receptor types with scopolamine and mecamylamine produced a large impairment in IT performance. The results indicate that both nicotinic and muscarinic receptors are involved in modulating IT, and that the two systems may function synergistically to modulate early visual information processing. These findings suggest that functional abnormalities in both nicotinic and muscarinic systems may underlie deficits in early visual information processing seen in disorders such as Alzheimer's disease and schizophrenia.


Assuntos
Processos Mentais , Receptores Muscarínicos/fisiologia , Receptores Nicotínicos/fisiologia , Adulto , Doença de Alzheimer/psicologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Psicologia do Esquizofrênico
13.
J Clin Oncol ; 19(14): 3422-33, 2001 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-11454891

RESUMO

PURPOSE: Preclinical studies have demonstrated that the adenovirus type 5 E1A gene is associated with antitumor activities by transcriptional repression of HER-2/neu and induction of apoptosis. Indeed, E1A gene therapy is known to induce regression of HER-2/neu-overexpressing breast and ovarian cancers in nude mice. Therefore, we evaluated the feasibility of intracavitary injection of E1A gene complexed with DC-Chol cationic liposome (DCC-E1A) in patients with both HER-2/neu-overexpressing and low HER-2/neu-expressing breast and ovarian cancers in a phase I clinical trial. PATIENTS AND METHODS: An E1A gene complexed with DCC-E1A cationic liposome was injected once a week into the thoracic or peritoneal cavity of 18 patients with advanced cancer of the breast (n = 6) or ovary (n = 12). RESULTS: E1A gene expression in tumor cells was detected by immunohistochemical staining and reverse transcriptase-polymerase chain reaction. This E1A gene expression was accompanied by HER-2/neu downregulation, increased apoptosis, and reduced proliferation. The most common treatment-related toxicities were fever, nausea, vomiting, and/or discomfort at the injection sites. CONCLUSION: These results argue for the feasibility of intracavitary DCC-E1A administration, provide a clear proof of preclinical concept, and warrant phase II trials to determine the antitumor activity of the E1A gene.


Assuntos
Proteínas E1A de Adenovirus/genética , Neoplasias da Mama/terapia , Transferência Genética Horizontal , Terapia Genética , Neoplasias Ovarianas/terapia , Adulto , Idoso , Apoptose , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Colesterol/análogos & derivados , Citocinas/metabolismo , Feminino , Expressão Gênica , Genes erbB-2 , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Injeções , Antígeno Ki-67 , Lipossomos , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Cavidade Peritoneal , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tórax , Células Tumorais Cultivadas
14.
Clin Cancer Res ; 6(1): 250-9, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10656456

RESUMO

HER-2/neu-overexpressing breast cancer cells are more resistant to the chemotherapeutic agent paclitaxel (Taxol) than low-HER-2/neu-expressing breast cancer cells, and the adenoviral type 5 EIA can down-regulate HER-2/neu overexpression. Therefore, in this study, we asked (a) whether EIA might sensitize response to paclitaxel in human HER-2/neu-overexpressing ovarian cancer cells, and, if so, what is the mechanism responsible; and (b) whether this enhanced chemosensitivity would translate into a therapeutic effect in an ovarian cancer xenograft model. Consequently, we demonstrated that: (a) adenovirus type 5 E1A could enhance the sensitivity of paclitaxel in paclitaxel-resistant HER-2/neu-overexpressing human ovarian cancer cells in vitro by inducing apoptosis, (b) this induction was heavily dependent on activation of the caspase-3 pathway, and (c) nude mice bearing i.p. HER-2/neu-overexpressing human ovarian cancer cells and treated with both paclitaxel and E1A gene therapy survived significantly longer than did mice treated only with paclitaxel or E1A gene therapy. Thus, we concluded that the E1A gene enhanced both the in vitro and in vivo sensitivity of paclitaxel in paclitaxel-resistant HER-2/ neu-overexpressing ovarian cancer SKOV3.ipl cells. Because a Phase I clinical trial using E1A gene targeted to HER-2/neu down-regulation has recently been completed, the current study also provided a scientific basis to further develop a novel therapy that combines paclitaxel and E1A gene therapy and its testing in a Phase II trial.


Assuntos
Proteínas E1A de Adenovirus/genética , Apoptose/fisiologia , Caspases/metabolismo , Terapia Genética , Neoplasias Ovarianas/terapia , Paclitaxel/toxicidade , Paclitaxel/uso terapêutico , Receptor ErbB-2/fisiologia , Proteínas E1A de Adenovirus/metabolismo , Adenovírus Humanos/genética , Animais , Apoptose/efeitos dos fármacos , Caspase 3 , Divisão Celular/efeitos dos fármacos , Feminino , Humanos , Camundongos , Camundongos Nus , Neoplasias Ovarianas/patologia , Receptor ErbB-2/genética , Sobrevida , Transplante Heterólogo , Células Tumorais Cultivadas
16.
Med J Aust ; 2(21): 947-9, 1968 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-5726949
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