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1.
World J Gastroenterol ; 28(35): 5217-5229, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36188718

RESUMO

BACKGROUND: Chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are known risk factors for liver disease, cirrhosis and hepatocellular carcinoma (HCC). There is substantial global variation in HBV and HCV prevalence resulting in variations in cirrhosis and HCC. We previously reported high prevalence of HBV and HCV infections in Somali immigrants seen at an academic medical center in Minnesota. AIM: To determine the prevalence of chronic viral hepatitis in Somali immigrants in Minnesota through a community-based screening program. METHODS: We conducted a prospective community-based participatory research study in the Somali community in Minnesota in partnership with community advisory boards, community clinics and local mosques between November 2010 and December 2015 (data was analyzed in 2020). Serum was tested for hepatitis B surface antigen, hepatitis B core antibody, hepatitis B surface antibody and anti-HCV antibody. RESULTS: Of 779 participants, 15.4% tested positive for chronic HBV infection, 50.2% for prior exposure to HBV and 7.6% for chronic HCV infection. Calculated age-adjusted frequencies in males and females for chronic HBV were 12.5% and 11.6%; for prior exposure to HBV were 44.8% and 41.3%; and for chronic HCV were 6.7% and 5.7%, respectively. Seven participants developed incident HCC during follow up. CONCLUSION: Chronic HBV and HCV are major risk factors for liver disease and HCC among Somali immigrants, with prevalence of both infections substantially higher than in the general United States population. Community-based screening is essential for identifying and providing health education and linkage to care for diagnosed patients.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Hepatite B , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Feminino , Hepacivirus , Hepatite B/complicações , Anticorpos Anti-Hepatite B , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/epidemiologia , Hepatite C/complicações , Hepatite C Crônica/complicações , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Humanos , Incidência , Cirrose Hepática/complicações , Neoplasias Hepáticas/patologia , Masculino , Minnesota/epidemiologia , Prevalência , Estudos Prospectivos , Somália
2.
J Low Genit Tract Dis ; 17(3): 280-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23486073

RESUMO

OBJECTIVE: It is unknown whether the Somali population in the United States is likely to participate in human papillomavirus (HPV) vaccination. We aimed to determine whether Somali girls living in a US community are following the recommendations for HPV vaccination. MATERIALS AND METHODS: We conducted a study of HPV vaccination among Somali girls seen at Mayo Clinic, Rochester, MN. Each Somali subject was matched by year of birth to white/non-Hispanic subjects in a 1:3 ratio. We abstracted information between August 1, 2006, and December 31, 2009, related to HPV vaccine series initiation and completion. Initiation and completion frequencies were compared between study groups using the χ(2) test. RESULTS: A total of 251 Somali and 727 white/non-Hispanic girls were identified, using the Rochester Epidemiology Project, who met all inclusion criteria for final analysis. A total of 114 Somali girls (45%) and 334 white/non-Hispanic girls (46%) initiated the series (odds ratio = 0.98; 95% confidence interval = 0.73-1.31), but only 59 Somali girls (52%) completed the vaccination series, compared with 240 (72%) of the white/non-Hispanic girls (odds ratio = 0.42; 95% confidence interval = 0.27-0.65). CONCLUSIONS: We found Somali girls to be generally accepting of initiating the HPV vaccine series but less likely to complete the series as compared with white non-Hispanic girls of the same age.


Assuntos
Etnicidade , Adesão à Medicação/estatística & dados numéricos , Vacinas contra Papillomavirus/administração & dosagem , Vacinação/estatística & dados numéricos , Adolescente , Criança , Feminino , Humanos , Estados Unidos
3.
J Mol Biomark Diagn ; 4(145): 1000145, 2013 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-25077038

RESUMO

BACKGROUND: Although cholangiocarcinoma (CC) is an uncommon and highly lethal malignancy, early detection enables the application of potentially curative therapies and improves survival. Consequently, tools to improve the early diagnosis of CC are urgently needed. During a screen for genes epigenetically suppressed by methylation in CC that might serve as methylation markers for CC, we found that the BMP3 gene is methylated in CC cell lines, but the potential diagnostic value and the function of BMP3 in CC are unknown. METHODS: We aimed to quantitatively assess BMP3 methylation in resected CC tumor specimens using methylation specific PCR and evaluate the tumor suppressor role of BMP3 in biliary cancer cell lines in comparison to an immortalized normal cholangiocyte cell line. Expression of BMP3 was quantified by mRNA levels before and after treatment with 5-Aza-2'-deoxycytidine and trichostatin A. After transfection with a BMP3-containing plasmid, cell viability was measured using the bromodeoxyuridine incorporation assay and apoptosis quantified by caspase assay. RESULTS: In primary CC tumor tissue specimens significantly more methylated BMP3 copies were found when compared to matched benign bile duct epithelium from the same patient, with high specificity. BMP3 expression was absent in cell lines with BMP3 methylation; this suppression of BMP3 expression was reversed by treatment with a DNA demethylating agent and histone de-acetylase inhibitor. Transfection of a BMP3-expressing construct into a BMP3-negative biliary cancer cell line restored BMP3 mRNA expression and reduced cell proliferation and cell viability while increasing the rate of apoptosis. CONCLUSION: These findings strongly support a tumor suppressor role for BMP3 in CC and suggest that BMP3 methylation may be a new biomarker for early detection of CCs. of the peptidome are also involved.

4.
Genes Chromosomes Cancer ; 52(3): 225-36, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23109092

RESUMO

Human sulfatase 2 (SULF2) functions as an oncoprotein in hepatocellular carcinoma (HCC) development by promoting tumor growth and metastasis via enhancement of fibroblast growth factor-2/extracellular signal-regulated kinase and WNT/ß-catenin signaling. Recent results implicate that SULF2 activates the transforming growth factor beta (TGFB) and Hedgehog/GLI1 pathways in HCC. OKN-007 is a novel phenyl-sulfonyl compound that inhibits the enzymatic activity of SULF2. To investigate the antitumor effect of OKN-007 in HCC, we treated Huh7 cells, which express high levels of SULF2, with OKN-007 and found that it significantly promoted tumor cell apoptosis and inhibited cell proliferation, viability, and migration. To understand the action of OKN-007 on SULF2, we used Huh7 cells which normally express SULF2 and Hep3B cells that do not normally express SULF2. Utilizing Huh7 cells transfected with short hairpin RNA targeting SULF2 and transfection of Hep3B cells with a SULF2 plasmid to enhance SULF2 expression, we showed that the antitumor activity of OKN-007 was more pronounced in cells expressing SULF2. Furthermore, in vivo experiments verified that OKN-007 repressed tumor growth significantly. These results identify SULF2 as an important target of the antitumor effect of OKN-007. To determine the molecular mechanism of the antitumor effect of OKN-007, both TGFB1/SMAD and Hedgehog/GLI1 signaling pathway activity were measured by Western blot and SMAD- or GLI-reporter luciferase assays. We found that both signaling pathways were inhibited by OKN-007. Together, these results show that OKN-007 can suppress TGFB1/SMAD and Hedgehog/GLI1 signaling via its inhibition of SULF2 enzymatic activity. We conclude that OKN-007 or more potent derivatives may be promising agents for the treatment of HCC.


Assuntos
Antineoplásicos/farmacologia , Benzenossulfonatos/farmacologia , Carcinoma Hepatocelular/metabolismo , Iminas/farmacologia , Neoplasias Hepáticas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfotransferases/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Expressão Gênica , Técnicas de Silenciamento de Genes , Proteínas Hedgehog/metabolismo , Humanos , Neoplasias Hepáticas/genética , Camundongos , Camundongos Nus , Proteínas Oncogênicas/metabolismo , Interferência de RNA , Proteína Smad2/metabolismo , Sulfatases , Sulfotransferases/genética , Transativadores/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína GLI1 em Dedos de Zinco
5.
PLoS One ; 7(11): e49581, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23185371

RESUMO

The role of the epithelial-to-mesenchymal transition (EMT) during hepatocellular carcinoma (HCC) progression is well established, however the regulatory mechanisms modulating this phenomenon remain unclear. Here, we demonstrate that transcription factor glioma-associated oncogene 1 (GLI1) modulates EMT through direct up-regulation of SNAI1 and serves as a downstream effector of the transforming growth factor-ß1 (TGFß1) pathway, a well-known regulator of EMT in cancer cells. Overexpression of GLI1 increased proliferation, viability, migration, invasion, and colony formation by HCC cells. Conversely, GLI1 knockdown led to a decrease in all the above-mentioned cancer-associated phenotypes in HCC cells. Further analysis of GLI1 regulated cellular functions showed that this transcription factor is able to induce EMT and identified SNAI1 as a transcriptional target of GLI1 mediating this cellular effect in HCC cells. Moreover, we demonstrated that an intact GLI1-SNAI1 axis is required by TGFß1 to induce EMT in these cells. Together, these findings define a novel cellular mechanism regulated by GLI1, which controls the growth and EMT phenotype in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Humanos , Microscopia de Fluorescência/métodos , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Fenótipo , Plasmídeos/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição da Família Snail , Transfecção , Proteína GLI1 em Dedos de Zinco
6.
Mayo Clin Proc ; 87(1): 17-24, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22212964

RESUMO

OBJECTIVE: To study the frequencies of chronic hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, and their associations with hepatocellular carcinoma (HCC) in immigrant Somalis seen at Mayo Clinic in Rochester, Minnesota. PATIENTS AND METHODS: We determined the frequencies of HBV and HCV infection and HCC in immigrant Somalis seen at Mayo Clinic from July 1, 1996, through October 31, 2009. Non-Somali Olmsted County residents served as controls. RESULTS: For Somali males and females, age-adjusted proportions (per 1000 population) were 209 and 123 for hepatitis B surface antigen (HBsAg), 644 and 541 for hepatitis B core antibody (HBcAb), and 99 and 66 for anti-HCV. The comparative proportions in non-Somalis were 20 and 9 for HBsAg, 126 and 97 for HBcAb, and 32 and 17 for anti-HCV. Hepatitis C virus RNA confirmed that 68 of 73 Somalis (93.2%) and 261 of 282 non-Somalis (92.6%) with positive anti-HCV test results had active HCV infection. Of 30 Somali patients with HCC, 22 (73.3%) tested anti-HCV positive (odds ratio [OR], 31.3; 95% confidence interval [CI], 13.0-75.5; P<.001; compared with anti-HCV-negative Somalis), 5 (16.7%) were HBsAg positive (OR, 1.4; 95% CI, 0.5-3.7; P=.53), and 18 (60.0%) were HBcAb positive (OR, 1.8; 95% CI, 0.8-4.2; P=.16). Viral hepatitis was diagnosed coincident with HCC in 9 of 20 patients (45.0%) with HCV-associated HCCs. Only 4 of 24 cases of HCC (16.7%) were detected during surveillance. CONCLUSION: Both HBV and HCV occurred frequently in this sample of Somali immigrants. However, HCV was the major risk factor for HCC. Screening Somali immigrants for HCV infection may enhance the prevention, early detection, and optimal treatment of HCC.


Assuntos
Carcinoma Hepatocelular/etnologia , Hepatite B Crônica/etnologia , Hepatite C Crônica/etnologia , Neoplasias Hepáticas/etnologia , Adulto , Distribuição por Idade , Idoso , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/virologia , Comorbidade , Feminino , Hepatite B Crônica/epidemiologia , Hepatite C Crônica/epidemiologia , Humanos , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Projetos Piloto , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Somália/etnologia , Adulto Jovem
8.
Hepatology ; 54(3): 940-8, 2011 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-21674559

RESUMO

UNLABELLED: Elevated serum immunoglobulin G4 (sIgG4) is a feature of autoimmune pancreatitis (AIP) and IgG4-associated cholangitis (IAC); a >2-fold increase in sIgG4 is considered highly specific for these disorders. Many patients with IAC present with biliary strictures and obstructive jaundice, making cholangiocarcinoma (CCA) an important differential diagnosis. We determined the value of sIgG4 in distinguishing IAC from CCA. sIgG4 levels were measured in a test cohort of 126 CCA and 50 IAC patients. The results were confirmed in a validation cohort of 161 CCA and 47 IAC patients. Of the 126 CCA patients in the test cohort, 17 (13.5%) had elevated sIgG4 (>140 mg/dL) and four (3.2%) had a >2-fold (>280 mg/dL) increase. Primary sclerosing cholangitis (PSC) was present in 31/126 CCA patients, of whom seven (22.6%) had elevated sIgG4 and two (6.5%) had a >2-fold elevation. Of the 50 IAC patients, 39 (78.0%) had elevated sIgG4 and 25 (50.0%) had a >2-fold increase. The results in the validation cohort were consistent with those of the test cohort. CONCLUSION: Although elevated sIgG4 levels are characteristic of IAC, some patients with CCA, particularly with PSC, have elevated sIgG4 levels, including a small percentage with a more than a 2-fold increase in sIgG4. Therefore, sIgG4 elevation alone does not exclude the diagnosis of CCA. Depending on the prevalence of the two diagnoses, the use of a 2-fold cutoff for sIgG4 may not reliably distinguish IAC from CCA. At a cutoff of 4 times the upper limit of normal, sIgG4 is 100% specific for IAC.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/diagnóstico , Colangite/diagnóstico , Imunoglobulina G/sangue , Adulto , Idoso , Neoplasias dos Ductos Biliares/imunologia , Neoplasias dos Ductos Biliares/mortalidade , Antígeno CA-19-9/sangue , Colangiocarcinoma/imunologia , Colangiocarcinoma/mortalidade , Colangite/imunologia , Colangite/mortalidade , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Liver Int ; 30(10): 1522-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21040406

RESUMO

BACKGROUND: Sulfatase 2 (SULF2), an extracellular heparan sulphate 6-O-endosulphatase, has an oncogenic effect in hepatocellular carcinoma (HCC) that is partially mediated through glypican 3, which promotes heparin-binding growth factor signalling and HCC cell growth. SULF2 also increases phosphorylation of the anti-apoptotic Akt kinase substrate GSK3ß and SULF2 expression is associated with a decreased apoptotic index in human HCCs. METHODS: We investigated the functional and mechanistic effects of SULF2 on drug-induced apoptosis of HCC cells using immunohistochemistry, Western immunoblotting, gene transfection, real-time quantitative polymerase chain reaction, MTT and apoptosis assays and immunocytochemistry. RESULTS: The increased expression of SULF2 in human HCCs was confirmed by immunohistochemistry and immunoblotting. Treatment with inhibitors of MEK, JNK and PI3 kinases decreased the viability of SULF2-negative Hep3B HCC cells and induced apoptotic caspase 3 and 7 activity, which was most strongly induced by the PI3K inhibitor LY294002. Forced expression of SULF2 in Hep3B cells significantly decreased activity of the apoptotic caspases 3 and 7 and induced resistance to LY294002-induced apoptosis. As expected, LY294002 inhibited activation of Akt kinase by PI3K. Conversely, knockdown of SULF2 using an shRNA construct targeting the SULF2 mRNA induced profound cell growth arrest and sensitized the endogenously SULF2-expressing HCC cell lines Huh7 and SNU182 to drug-induced apoptosis. The effects of knockdown of SULF2 on HCC cells were mediated by decreased Akt phosphorylation, downregulation of cyclin D1 and the anti-apoptotic molecule Bcl-2, and upregulation of the pro-apoptotic molecule BAD. CONCLUSION: The prosurvival, anti-apoptotic effect of SULF2 in HCC is mediated through activation of the PI3K/Akt pathway.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/enzimologia , Cromonas/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias Hepáticas/enzimologia , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Sulfotransferases/metabolismo , Western Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Imuno-Histoquímica , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Sulfatases , Sulfotransferases/genética , Transfecção , Proteína de Morte Celular Associada a bcl/metabolismo
10.
Hepatology ; 52(5): 1680-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20725905

RESUMO

UNLABELLED: Heparan sulfate proteoglycans (HSPGs) act as coreceptors or storage sites for growth factors and cytokines such as fibroblast growth factor and Wnts. Glypican 3 (GPC3) is the most highly expressed HSPG in hepatocellular carcinoma (HCC). Sulfatase 2 (SULF2), an enzyme with 6-O-desulfatase activity on HSPGs, is up-regulated in 60% of primary HCCs and is associated with a worse prognosis. We have previously shown that the oncogenic effect of SULF2 in HCC may be mediated in part through up-regulation of GPC3. Here we demonstrate that GPC3 stimulates the Wnt/ß-catenin pathway and mediates the oncogenic function of SULF2 in HCC. Wnt signaling in vitro and in vivo was assessed in SULF2-negative Hep3B HCC cells transfected with SULF2 and in SULF2-expressing Huh7 cells transfected with short hairpin RNA targeting SULF2. The interaction between GPC3, SULF2, and Wnt3a was assessed by coimmunoprecipitation and flow cytometry. ß-catenin-dependent transcriptional activity was assessed with the TOPFLASH (T cell factor reporter plasmid) luciferase assay. In HCC cells, SULF2 increased cell surface GPC3 and Wnt3a expression, stabilized ß-catenin, and activated T cell factor transcription factor activity and expression of the Wnt/ß-catenin target gene cyclin D1. Opposite effects were observed in SULF2-knockdown models. In vivo, nude mouse xenografts established from SULF2-transfected Hep3B cells showed enhanced GPC3, Wnt3a, and ß-catenin levels. CONCLUSION: Together, these findings identify a novel mechanism mediating the oncogenic function of SULF2 in HCC that includes GPC3-mediated activation of Wnt signaling via the Wnt3a/glycogen synthase kinase 3 beta axis.


Assuntos
Carcinoma Hepatocelular/enzimologia , Neoplasias Hepáticas/enzimologia , Sulfotransferases/sangue , Animais , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Ativação Enzimática , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Glipicanas/sangue , Glipicanas/genética , Humanos , Antígeno Ki-67/genética , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Luciferases/genética , Camundongos , Camundongos Nus , Plasmídeos/genética , Sulfatases , Transfecção , Proteínas Wnt/genética , Proteína Wnt3 , Proteína Wnt3A
11.
J Hepatol ; 50(6): 1112-21, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19376607

RESUMO

BACKGROUND/AIMS: There are limited chemotherapy options for hepatocellular carcinoma (HCC). The heparin-degrading endosulfatase SULF1 functions as a liver tumor suppressor. We investigated the effects of the histone deacetylase inhibitor apicidin in combination with doxorubicin in SULF1-expressing HCC cells in vitro and in SULF1-expressing xenografts in nude mice. METHODS: We evaluated the effects of apicidin alone or combined with doxorubicin on apoptosis, caspase activity, and phosphorylation of Erk and Akt in SULF1-transfected Huh7 and Hep3B cells in vitro and in vivo. RESULTS: Apicidin induced HCC cell apoptosis and caspase activation in a dose- and time-dependent manner. Apicidin-induced caspase activation was significantly inhibited by the caspase inhibitor Z-Vad-fmk. Apicidin also decreased phosphorylation of both Erk and Akt. Expression of constitutively-active Mek1 and Akt significantly decreased apicidin-induced apoptosis. The combination of doxorubicin with apicidin significantly increased the anti-tumor effect in the SULF1-expressing Huh7 and Hep3B cells as compared to either apicidin or doxorubicin alone, both in vitro and in vivo. CONCLUSIONS: The combination of a histone deacetylase inhibitor with doxorubicin may be a novel and promising therapeutic modality for HCCs, particularly for SULF1-expressing HCCs.


Assuntos
Doxorrubicina/administração & dosagem , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Neoplasias Hepáticas Experimentais/enzimologia , Peptídeos Cíclicos/administração & dosagem , Sulfotransferases/metabolismo , Animais , Antibióticos Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Inibidores Enzimáticos/administração & dosagem , Inibidores de Histona Desacetilases , Humanos , Neoplasias Hepáticas Experimentais/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sulfotransferases/genética , Transfecção , Transplante Heterólogo
12.
Hepatology ; 47(4): 1211-22, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18318435

RESUMO

UNLABELLED: It has been shown that the heparin-degrading endosulfatase, sulfatase 1 (SULF1), functions as a liver tumor suppressor, but the role of the related sulfatase, sulfatase 2 (SULF2), in liver carcinogenesis remains to be elucidated. We investigated the effect of SULF2 on liver tumorigenesis. Expression of SULF2 was increased in 79 (57%) of 139 hepatocellular carcinomas (HCCs) and 8 (73%) of 11 HCC cell lines. Forced expression of SULF2 increased HCC cell growth and migration, whereas knockdown of SULF2 using short hairpin RNA targeting SULF2 abrogated HCC cell proliferation and migration in vitro. Because SULF1 and SULF2 desulfate heparan sulfate proteoglycans (HSPGs) and the HSPG glypican 3 (GPC3) is up-regulated in HCC, we investigated the effects of SULF2 on GPC3 expression and the association of SULF2 with GPC3. SULF2-mediated cell growth was associated with increased binding of fibroblast growth factor 2 (FGF2), phosphorylation of extracellular signal-regulated kinase and AKT, and expression of GPC3. Knockdown of GPC3 attenuated FGF2 binding in SULF2-expressing HCC cells. The effects of SULF2 on up-regulation of GPC3 and tumor growth were confirmed in nude mouse xenografts. Moreover, HCC patients with increased SULF2 expression in resected HCC tissues had a worse prognosis and a higher rate of recurrence after surgery. CONCLUSION: In contrast to the tumor suppressor effect of SULF1, SULF2 has an oncogenic effect in HCC mediated in part through up-regulation of FGF signaling and GPC3 expression.


Assuntos
Carcinoma Hepatocelular/enzimologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glipicanas/metabolismo , Neoplasias Hepáticas/enzimologia , Sulfotransferases/metabolismo , Animais , Carcinoma Hepatocelular/diagnóstico , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células , Humanos , Neoplasias Hepáticas/diagnóstico , Camundongos , Camundongos Nus , Prognóstico , Transdução de Sinais/fisiologia , Sulfatases , Regulação para Cima
13.
Liver Int ; 28(1): 12-27, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18031477

RESUMO

Cholangiocarcinomas (CCs) are highly lethal malignant tumours arising from the biliary tract epithelium. The disease is notoriously difficult to diagnose and is usually fatal because of its typically late clinical presentation and the lack of effective non-surgical therapeutic modalities. The overall survival rate, including resected patients is poor, with less than 5% of patients surviving 5 years, a rate which has not changed significantly over the past 30 years. Although CC is a relatively uncommon tumor, interest in this disease is rising as incidence and mortality rates for intrahepatic cholangiocarcinoma are increasing markedly worldwide. A variety of risk factors, including primary sclerosing cholangitis, liver fluke infestation, and hepatolithiasis have been described. However, for most CCs the cause is unknown, and affected individuals have no history of exposure to, or association with, known risk factors. Recent advances in molecular pathogenesis have highlighted the importance of epigenetic alterations in the form of promoter region hypermethylation and histone deacetylation in addition to genetic changes in the process of cholangiocarcinogenesis. This review provides a comprehensive overview of the genes reported to be methylated in CC to date and their putative roles in cholangiocarcinogenesis. Future directions in the study of methylated genes and their potential roles as diagnostic and prognostic markers are also discussed.


Assuntos
Colangiocarcinoma/etiologia , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Metilação de DNA , Epigênese Genética/genética , Histonas/metabolismo , Colangiocarcinoma/terapia , Humanos , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Risco
14.
J Gastrointest Cancer ; 39(1-4): 149-58, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19373441

RESUMO

INTRODUCTION: Human sulfatase 1 (SULF1) was recently identified and shown to desulfate cellular heparan sulfate proteoglycans (HSPGs). Since sulfated HSPGs serve as co-receptors for many growth factors and cytokines, SULF1 was predicted to modulate growth factor and cytokine signaling. DISCUSSION: The role of SULF1 in growth factor signaling and its effects on human tumorigenesis are under active investigation. Initial results show that SULF1 inhibits the co-receptor function of HSPGs in multiple receptor tyrosine kinase signaling pathways, particularly by the heparin binding growth factors--fibroblast growth factor 2, vascular endothelial growth factor, hepatocyte growth factor, PDGF, and heparin-binding epidermal growth factor (HB-EGF). SULF1 is downregulated in the majority of cancer cell lines examined, and forced expression of SULF1 decreases cell proliferation, migration, and invasion. SULF1 also promotes drug-induced apoptosis of cancer cells in vitro and inhibits tumorigenesis and angiogenesis in vivo. CONCLUSION: Strategies targeting SULF1 or the interaction between SULF1 and the related sulfatase 2 will potentially be important in developing novel cancer therapies.


Assuntos
Neoplasias/etiologia , Sulfotransferases/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Apoptose , Metilação de DNA , Fator 2 de Crescimento de Fibroblastos/fisiologia , Proteoglicanas de Heparan Sulfato/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Inibidores de Histona Desacetilases , Humanos , Sistema de Sinalização das MAP Quinases , Neoplasias/patologia , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Sulfotransferases/genética , Fator A de Crescimento do Endotélio Vascular/fisiologia
15.
Cancer Epidemiol Biomarkers Prev ; 16(12): 2686-96, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18086775

RESUMO

Discriminant markers are required for accurate cancer screening. We evaluated genes frequently methylated in colorectal neoplasia to identify the most discriminant ones. Four genes specifically methylated in colorectal cancer [bone morphogenetic protein 3 (BMP3), EYA2, aristaless-like homeobox-4 (ALX4), and vimentin] were selected from 41 candidate genes and evaluated on 74 cancers, 62 adenomas, and 70 normal epithelia. Methylation status was analyzed qualitatively and quantitatively and confirmed by bisulfite genomic sequencing. Effect of methylation on gene expression was evaluated in five colon cancer cell lines. K-ras and BRAF mutations were detected by sequencing. Methylation of BMP3, EYA2, ALX4, or vimentin was detected respectively in 66%, 66%, 68%, and 72% of cancers; 74%, 48%, 89%, and 84% of adenomas; and 7%, 5%, 11%, and 11% of normal epithelia (P < 0.01, cancer or adenoma versus normal). Based on area under the curve analyses, discrimination was not significantly improved by combining markers. Comethylation was frequent (two genes or more in 72% of cancers and 84% of adenomas), associated with proximal neoplasm site (P < 0.001), and linked with both BRAF and K-ras mutations (P < 0.01). Cell line experiments supported silencing of expression by methylation in all four study genes. This study shows BMP3, EYA2, ALX4, and vimentin genes are methylated in most colorectal neoplasms but rarely in normal epithelia. Comethylation of these genes is common, and pursuit of complementary markers for methylation-negative neoplasms is a rational strategy to optimize screening sensitivity.


Assuntos
Adenocarcinoma/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Metilação de DNA , Programas de Rastreamento/métodos , Adenocarcinoma/prevenção & controle , Adenoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína Morfogenética Óssea 3 , Proteínas Morfogenéticas Ósseas/genética , Neoplasias Colorretais/prevenção & controle , Primers do DNA , DNA de Neoplasias/genética , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Nucleares/genética , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras) , Curva ROC , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade , Fatores de Transcrição/genética , Vimentina/genética , Proteínas ras/genética
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