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1.
Lancet Oncol ; 20(1): 110-119, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30522967

RESUMO

BACKGROUND: Glioblastoma is a highly vascularised tumour and there are few treatment options after disease recurrence. Regorafenib is an oral multikinase inhibitor of angiogenic, stromal, and oncogenic receptor tyrosine kinases. We aimed to assess the efficacy and safety of regorafenib in the treatment of recurrent glioblastoma. METHODS: REGOMA is a randomised, multicentre, open-label phase 2 trial done in ten centres in Italy. Eligible patients (aged ≥18 years) with histologically confirmed glioblastoma, Eastern Cooperative Oncology Group performance status 0 or 1, and documented disease progression after surgery followed by radiotherapy and temozolomide chemoradiotherapy were randomly assigned (1:1) by a web-based system, stratified by centre and surgery at recurrence (yes vs no), to receive regorafenib 160 mg once daily for the first 3 weeks of each 4-week cycle or lomustine 110 mg/m2 once every 6 weeks until disease progression, death, unacceptable toxicity, or consent withdrawal. The primary endpoint was overall survival in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02926222, and is currently in follow-up. FINDINGS: Between Nov 27, 2015, and Feb 23, 2017, 124 patients were screened and 119 eligible patients were randomly assigned to receive regorafenib (n=59) or lomustine (n=60). Median follow-up was 15·4 months (IQR 13·8-18·1). At the analysis cutoff date, 99 (83%) of 119 patients had died: 42 (71%) of 59 in the regorafenib group and 57 (95%) of 60 in the lomustine group. Overall survival was significantly improved in the regorafenib group compared with the lomustine group, with a median overall survival of 7·4 months (95% CI 5·8-12·0) in the regorafenib group and 5·6 months (4·7-7·3) in the lomustine group (hazard ratio 0·50, 95% CI 0·33-0·75; log-rank p=0·0009). Grade 3-4 treatment-related adverse events occurred in 33 (56%) of 59 patients treated with regorafenib and 24 (40%) of 60 with lomustine. The most frequent grade 3 or 4 adverse events related to regorafenib were hand-foot skin reaction, increased lipase, and blood bilirubin increased (in six [10%] of 59 patients each). In the lomustine group, the most common grade 3 or 4 adverse events were decreased platelet count (eight [13%] of 60 patients), decreased lymphocyte count (eight [13%]), and neutropenia (seven [12%]). No death was considered by the investigators to be drug related. INTERPRETATION: REGOMA showed an encouraging overall survival benefit of regorafenib in recurrent glioblastoma. This drug might be a new potential treatment for these patients and should be investigated in an adequately powered phase 3 study. FUNDING: Veneto Institute of Oncology and Bayer Italy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Glioblastoma/tratamento farmacológico , Lomustina/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Piridinas/uso terapêutico , Idoso , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/efeitos adversos , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Lomustina/administração & dosagem , Lomustina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Piridinas/administração & dosagem , Piridinas/efeitos adversos , Recidiva , Análise de Sobrevida , Resultado do Tratamento
2.
J Neurooncol ; 128(3): 481-6, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27165580

RESUMO

The optimal treatment of recurrent glioblastoma (GBM) in elderly patients is unclear. Fotemustine (FTM) is a third-generation nitrosourea showing efficacy in gliomas and it has been used with different schedules in adult patients. We performed, for the first time anywhere, a mono-institutional retrospective study to analyze the clinical outcome of an alternative fotemustine schedule in elderly patients with recurrent GBM. Retrospectively, we analyzed all GBM patients 65 years or older previously treated with the combination of radiation therapy and temozolomide (TMZ), receiving an alternative FTM schedule as second-line treatment at our Oncological Center from October 2011 to October 2014 with an ECOG PS ≤ 2. FTM was administrated at 80 mg/m(2) every 2 weeks for five consecutive administrations (induction phase), and then every 4 weeks at 80 mg/m(2) as maintenance. We enrolled 44 patients, 33 males and 11 females; average age was 70 years. ECOG PS was 0-1 in 80 % of the patients. 38 patients relapsed during temozolomide (TMZ) therapy. MGMT methylation status was analyzed in 34 patients and MGMT was methylated in 53 % of the patients. The median progression free survival (PFS) and overall survival (OS) from FTM treatment was 4.1 months (95 % CI 3.1-5.2) and 7 months (95 % CI 5.2-8.4), respectively. Patients with MGMT methylated status and patients who relapsed after completing TMZ therapy had a longer PFS and OS from the beginning of FTM. Thrombocytopenia was the most frequent grade 3-4 haematological toxicity (9 %). The alternative schedule of FTM may be an active and safe treatment for elderly patients with recurrent glioblastoma, especially patients with methylated MGMT and who relapsed after completing temozolomide therapy.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Compostos de Nitrosoureia/administração & dosagem , Compostos Organofosforados/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Dacarbazina/análogos & derivados , Dacarbazina/uso terapêutico , Esquema de Medicação , Feminino , Humanos , Masculino , Recidiva Local de Neoplasia/genética , Compostos de Nitrosoureia/efeitos adversos , Compostos Organofosforados/efeitos adversos , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Temozolomida , Resultado do Tratamento , Proteínas Supressoras de Tumor/genética
3.
Anticancer Drugs ; 23(7): 749-53, 2012 08.
Artigo em Inglês | MEDLINE | ID: mdl-22382388

RESUMO

High-grade gliomas (HGG) are aggressive and highly vascularized brain tumours. Despite multimodality therapy including surgery, radiation therapy and in many cases temozolomide chemotherapy, the prognosis is dismal. Salvage therapies following progression after radiation therapy and chemotherapy have historically yielded disappointing results. Bevacizumab is an interesting antiangiogenic drug used as a second-line treatment but although most patients benefit, essentially all patients ultimately progress. Moreover, some clinical studies have documented low activity of a second attempt at vascular endothelial growth factor pathway inhibition after failure of a first. The use of another drug with a different angiogenic pathway inhibition may probably result in a higher activity. Here, we describe, to our knowledge for the first time, the activity and safety of cilengitide, an agent with a different antiangiogenic and anti-invasive activity, administered in two bevacizumab-refractory patients with HGG. In addition, we present a rapid review of the activity of cilengitide in HGG.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Astrocitoma/tratamento farmacológico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Venenos de Serpentes/uso terapêutico , Adulto , Feminino , Humanos , Integrina alfaVbeta3/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Glicoproteínas da Membrana de Plaquetas/antagonistas & inibidores , Terapia de Salvação
4.
J Clin Invest ; 117(9): 2713-22, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17717605

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide, accounting for an estimated 600,000 deaths annually. Aberrant methylation, consisting of DNA hypomethylation and/or promoter gene CpG hypermethylation, is implicated in the development of a variety of solid tumors, including HCC. We analyzed the global levels of DNA methylation as well as the methylation status of 105 putative tumor suppressor genes and found that the extent of genome-wide hypomethylation and CpG hypermethylation correlates with biological features and clinical outcome of HCC patients. We identified activation of Ras and downstream Ras effectors (ERK, AKT, and RAL) due to epigenetic silencing of inhibitors of the Ras pathway in all HCC. Further, selective inactivation of SPRY1 and -2, DAB2, and SOCS4 and -5 genes and inhibitors of angiogenesis (BNIP3, BNIP3L, IGFBP3, and EGLN2) was associated with poor prognosis. Importantly, several epigenetically silenced putative tumor suppressor genes found in HCC were also inactivated in the nontumorous liver. Our results assign both therapeutic and chemopreventive significance to methylation patterns in human HCC and open the possibility of using molecular targets, including those identified in this study, to effectively inhibit HCC development and progression.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Metilação de DNA , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/metabolismo , Progressão da Doença , Inibidores Enzimáticos/farmacologia , Feminino , Genoma Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Proteínas ras/antagonistas & inibidores , Proteínas ras/metabolismo
5.
Anticancer Drugs ; 21(2): 210-3, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19952729

RESUMO

In recent years with the development of targeted agents such as bevacizumab, sunitinib, sorafenib, temsirolimus, and everolimus, the treatment of metastatic renal cell carcinoma has changed dramatically. In clinical practice, sunitinib and bevacizumab are reserved for first-line treatment, but despite various guidelines, optimal treatment is still uncertain. We present, for the first time, a case of a good response to second-line bevacizumab and interferon-alpha in a patient who failed classical sunitinib treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Bevacizumab , Carcinoma de Células Renais/secundário , Feminino , Humanos , Indóis/administração & dosagem , Interferon-alfa/administração & dosagem , Neoplasias Renais/patologia , Neoplasias Pulmonares/secundário , Metástase Linfática , Prognóstico , Pirróis/administração & dosagem , Terapia de Salvação , Sunitinibe , Resultado do Tratamento
6.
Gastroenterology ; 135(4): 1322-32, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18722373

RESUMO

BACKGROUND & AIMS: Resistance to apoptosis is essential for cancer growth. We previously reported that hepatic coexpression of c-Myc and E2F1, 2 key regulators of proliferation and apoptosis, enhanced hepatocellular carcinoma (HCC) development in transgenic mice. Here, we investigated the molecular mechanisms underlying oncogenic cooperation between c-Myc and E2F1 in relationship to human liver cancer. METHODS: Activation of pro- and antiapoptotic cascades was assessed by immunoblotting in experimental HCC models and in human HCC. Effect of antisense oligodeoxy nucleotides against c-Myc and E2F1 was studied in human HCC cell lines. Suppression of catalytic subunit p110alpha of phosphatidylinositol 3-kinase (PIK3CA)/Akt, mammalian target of rapamycin (mTOR), and cyclooxygenase (COX)-2 pathways was achieved by pharmacologic inhibitors and small interfering RNA in human and mouse HCC cell lines. RESULTS: Coexpression with E2F1 did not increase proliferation triggered by c-Myc overexpression but conferred a strong resistance to c-Myc-initiated apoptosis via concomitant induction of PIK3CA/Akt/mTOR and c-Myb/COX-2 survival pathways. COX-2 was not induced in c-Myc and rarely in E2F1 tumors. In human HCC, PIK3CA/Akt/mTOR and c-Myb/COX-2 pathways were similarly activated, with levels of PIK3CA/Akt, mTOR, and c-Myb being inversely associated with patients' survival length. Silencing c-Myc and E2F1 reduced PIK3CA/Akt and mTOR and completely abolished c-Myb and COX-2 expression in human HCC cell lines. Finally, simultaneous inhibition of PIK3CA/Akt/mTOR and COX-2 activity in in vitro models caused massive apoptosis of neoplastic hepatocytes. CONCLUSIONS: E2F1 may function as a critical antiapoptotic factor both in human and in rodent liver cancer through its ability to counteract c-Myc-driven apoptosis via activation of PIK3CA/Akt/mTOR and c-Myb/COX-2 pathways.


Assuntos
Apoptose/fisiologia , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/fisiopatologia , Fator de Transcrição E2F1/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Idoso , Animais , Carcinoma Hepatocelular/metabolismo , Proteínas de Transporte/metabolismo , Sobrevivência Celular/fisiologia , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Fator de Transcrição E2F1/genética , Feminino , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Complexos Multiproteicos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Serina-Treonina Quinases TOR , Fatores de Transcrição/metabolismo , Transgenes/fisiologia
7.
Crit Rev Oncol Hematol ; 111: 94-102, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28259301

RESUMO

BACKGROUND: glioblastomas are highly vascularized tumors and various antiangiogenic drugs have been investigated in clinical trials showing unclear results. We performed a systematic review and a meta-analysis to clarify and evaluate their effectiveness in glioblastoma patients. PATIENTS AND METHODS: we searched relevant published and unpublished randomized clinical trials analyzing antiangiogenic drugs versus chemotherapy in glioblastoma patients from January 2006 to January 2016 in MEDLINE, WEB of SCIENCE, ASCO, ESMO and SNO databases. RESULTS: fourteen randomized clinical trials were identified (7 with bevacizumab, 2 cilengitide, 1 enzastaurin, 1 dasatinib, 1 vandetanib, 1 temsirolimus, 1 cediranib) including 4330 patients. Antiangiogenic drugs showed no improvement in overall survival with a pooled HR of 1.00, a trend for an inferior outcome, in terms of overall survival, was observed in the group of patients receiving antiangiogenic drug alone compared to cytotoxic drug alone (HR=1.24, p=0.056). Bevacizumab did not improve overall survival. Twelve trials (4113 patients) were analyzed for progression-free survival. Among antiangiogenic drugs, only bevacizumab demonstrated an improvement of progression-free survival (HR=0.63, p<0.001), both alone (HR=0.60, p=0.003) or in combination to chemotherapy (HR=0.63; p<0.001), both as first-line treatment (HR=0.70, p<0.001) or in recurrent disease (HR=0.52, p<0.001). CONCLUSIONS: antiangiogenic drugs did not improve overall survival in glioblastoma patients, either as first or second-line treatment, and either as single agent or in combination with chemotherapy. Among antiangiogenic drugs, only bevacizumab improved progression-free survival regardless of treatment line, both as single agent or in combination with chemotherapy.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/irrigação sanguínea , Intervalo Livre de Doença , Glioblastoma/irrigação sanguínea , Humanos , Neovascularização Patológica/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Arterioscler Thromb Vasc Biol ; 24(1): 129-35, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14592849

RESUMO

OBJECTIVES: Based on previous observations on apolipoprotein(a), apo(a), in human unstable carotid plaques, we explored whether in the inflammatory environment of human atheroma, proteolytic events affect other hepatic and topically generated proteins in relation to the issue of plaque stability. METHODS AND RESULTS: Forty unstable and 24 stable plaques from endarterectomy segments of affected human carotid arteries were extracted with buffered saline (PBS) and then 6 mol/L guanidine-hydrochloride (GdHCl) to identify loosely and tightly bound products, respectively. The extracts were studied before and after ultracentrifugation at d 1.21 g/mL. In the extracts, the concentrations of interleukin (IL)-6, -8, and -18 were significantly higher in the unstable plaques and correlated to those of MMP-2 and MMP-9. By Western blots, both apoB and apo(a) were highly fragmented and mostly present in the d 1.21 bottom that also contained fragments of apoE (10 and 22 kDa), decorin, biglycan, and versican. Fragmentation was higher in the unstable plaques. In baseline plasmas, concentrations of lipids, lipoproteins, and ILs did not differ between patients with unstable and stable plaques. CONCLUSIONS: In unstable and to a lesser extent in stable plaques, there is a proinflammatory and proteolytic microenvironment with the generation of fragments with potential pathobiological significance that requires investigation.


Assuntos
Estenose das Carótidas/metabolismo , Proteínas/metabolismo , Vasculite/metabolismo , Idoso , Apolipoproteínas/análise , Biomarcadores , Estenose das Carótidas/patologia , Estenose das Carótidas/cirurgia , Decorina , Endarterectomia das Carótidas , Proteínas da Matriz Extracelular , Feminino , Guanidina/farmacologia , Humanos , Interleucinas/análise , Masculino , Metaloproteinases da Matriz/análise , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Proteoglicanas/análise , Vasculite/patologia
9.
Cancer ; 117(1): 125-33, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-21058409

RESUMO

BACKGROUND: Over the years, doxorubicin and gemcitabine have been among the most widely used drugs for hepatocellular carcinoma (HCC), with relative efficacy. The authors report the results of a phase 2 study of the combination of gemcitabine plus pegylated liposomal doxorubicin. METHODS: Patients with advanced HCC received combination chemotherapy with gemcitabine 1000 mg/m² on Days 1 and 8, followed by pegylated liposomal doxorubicin 30 mg/m² on Day 1. Treatment was repeated every 4 weeks to a maximum of 8 cycles. Primary endpoint was overall response rate, and secondary endpoints were time to disease progression (TTP), overall survival (OS), and toxicity. RESULTS: Forty-one patients were enrolled and were evaluable for response, toxicity, and survival. A total of 194 cycles of treatment were administered. Three (7%) patients had a complete response, and 1 of these patients underwent liver transplantation. Seven (17%) patients had a partial response and, among these patients, 1 patient underwent surgical resection. Among the 31 patients who had initial alpha-fetoprotein levels >400 ng/mL, 20 (64.5%) had a >20% decrease after 2 cycles of treatment. The median TTP and OS were 5.8 and 22.5 months, respectively. Hematologic toxicity was the most common side effect, including neutropenia (17%) and anemia (7%). CONCLUSIONS: The combination of gemcitabine plus pegylated liposomal doxorubicin was active and safe in advanced HCC. Moreover, this treatment induced some complete responses and converted some untreatable HCCs into lesions eligible for resection or transplantation.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Desoxicitidina/análogos & derivados , Doxorrubicina/análogos & derivados , Neoplasias Hepáticas/tratamento farmacológico , Polietilenoglicóis/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Hepatocelular/mortalidade , Desoxicitidina/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Gencitabina
10.
Cancer Chemother Pharmacol ; 64(6): 1195-200, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19306093

RESUMO

PURPOSE: To investigate the allelic status of the thymidylate synthetase (TYMS) gene, located at chromosome band 18p11.32, in renal cell carcinoma (RCC). TYMS is a key target of the 5-fluorouracil (5-FU)-based class of drugs, frequently considered in combination therapies in advanced RCC. TYMS variants, such as the TYMS polymorphic 5'-untranslated region variable number tandem repeat sequence (VNTR), are under investigation to guide 5-FU treatment. Yet, no information is available with regard to changes in TYMS allele frequencies in RCC malignances. METHODS: Blood and matched tumor samples were collected from 41 histological proven clear cell RCC affected patients (30 males, 11 females.). TYMS VNTR genotype was first determined in blood to identify heterozygotes employing PCR techniques. To evaluate for allelic imbalance, fragment analysis was performed both in blood and matched tumor DNA of the heterozygote patients. Microsatellite analysis, employing the markers D18S59 and D18S476 mapping, respectively, at the TYMS locus (18p11.32) and 1.5 Mb downstream of the TYMS gene sequence (18p11.31), was performed to confirm TYMS allelic imbalance in tumors. RESULTS: Germ-line TYMS VNTR distribution was: 2R/2R (19.5%), TYMS 2R/3R (36.6%) and TYMS 3R/3R (43.9%). Allelic imbalance for the TYMS tandem repeat region was detected in 26.6% of the heterozygote patients. Microsatellite analysis confirmed the allelic imbalance detected by TYMS VNTR analysis and revealed that the overall frequence of allelic imbalance of chromosome band 18p11.32 was 35%, while the overall allelic imbalance of chromosome band 18p11.31 was 28%. CONCLUSIONS: By focusing on the TYMS polymorphic variants in renal cancer, we here provide evidence, to our knowledge, for the first time showing loss of 18p11.32 and 18p11.31 in renal cell carcinomas. As allelic imbalances involving TYMS locus may be an important variable affecting 5-FU responsiveness, this study may contribute to explain different responses of advanced RCC in combined chemotherapeutic regimens incorporating fluoropyridines.


Assuntos
Desequilíbrio Alélico/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Timidilato Sintase/genética , Regiões 5' não Traduzidas/genética , Idoso , Feminino , Frequência do Gene/genética , Genótipo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética
11.
Gastroenterology ; 130(4): 1117-28, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16618406

RESUMO

BACKGROUND & AIMS: Although the natural history and pathologic characteristics of human hepatocellular carcinoma (HCC) are well documented, the molecular pathogenesis of HCC remains poorly understood. Here, we define the role for Ras and Janus kinase (Jak)/signal transducer and activator of transcription (Stat) pathways in human HCC. METHODS: Promoter and genomic status of Ras and Jak/Stat inhibitors were assessed in 80 HCCs by methylation-specific polymerase chain reaction and microsatellite analysis. Activation of Ras and Jak/Stat signaling pathways was determined by DNA sequencing, Western blot, and immunoprecipitation analysis. Suppression of Ras and Jak/Stat pathways in HCC cell lines was evaluated by viability and apoptosis assays. RESULTS: Activation of Ras and Jak/Stat pathways was enhanced in all HCCs when compared with nonneoplastic surrounding and normal livers coincidently with the suppression of at least 1 Ras (RASSF1A and/or NORE1A) and 2 Jak/Stat inhibitors (cytokine-inducible SH2-protein [CIS]; suppressor of cytokine signaling [SOCS]1, 2, 3; and SH2-containing phosphatases [SHP1]). HCC associated with cirrhosis showed significantly higher frequency of RASSF1A, CIS, and SOCS1 promoter methylation than HCC without cirrhosis (P < .002, P < .02, and P < .02, respectively). Furthermore, aberrant methylation of NORE1A and SOCS3 promoters was observed only in a subclass of HCC with poor survival, suggesting that inactivation of these 2 genes might be involved in HCC progression. Combined treatment of HCC cell lines with Ras and Jak/Stat inhibitors as well as with the demethylating agent zebularine induced a strong apoptotic response. CONCLUSIONS: These data demonstrate the ubiquitous activation of Ras and Jak/Stat pathways in HCC and suggest the potential use of Ras and Jak/Stat inhibitors and demethylating agents as therapeutic modality for human liver cancer.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição STAT/metabolismo , Proteínas ras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Proteínas Reguladoras de Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Divisão Celular , Metilação de DNA , Regulação para Baixo , Ativação Enzimática , Feminino , Humanos , Proteínas Imediatamente Precoces/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Regiões Promotoras Genéticas , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases/metabolismo , Transdução de Sinais , Proteínas Supressoras da Sinalização de Citocina/genética , Proteínas Supressoras da Sinalização de Citocina/metabolismo , Distribuição Tecidual , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
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