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1.
Mol Cell ; 58(6): 989-1000, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26051179

RESUMO

The regulation of RagA(GTP) is important for amino-acid-induced mTORC1 activation. Although GATOR1 complex has been identified as a negative regulator for mTORC1 by hydrolyzing RagA(GTP), how GATOR1 is recruited to RagA to attenuate mTORC1 signaling remains unclear. Moreover, how mTORC1 signaling is terminated upon amino acid stimulation is also unknown. We show that the recruitment of GATOR1 to RagA is induced by amino acids in an mTORC1-dependent manner. Skp2 E3 ligase drives K63-linked ubiquitination of RagA, which facilitates GATOR1 recruitment and RagA(GTP) hydrolysis, thereby providing a negative feedback loop to attenuate mTORC1 lysosomal recruitment and prevent mTORC1 hyperactivation. We further demonstrate that Skp2 promotes autophagy but inhibits cell size and cilia growth through RagA ubiquitination and mTORC1 inhibition. We thereby propose a negative feedback whereby Skp2-mediated RagA ubiquitination recruits GATOR1 to restrict mTORC1 signaling upon sustained amino acid stimulation, which serves a critical mechanism to maintain proper cellular functions.


Assuntos
Aminoácidos/farmacologia , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia/genética , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Retroalimentação Fisiológica/efeitos dos fármacos , Guanosina Trifosfato/metabolismo , Células HEK293 , Humanos , Immunoblotting , Lisina/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Knockout , Microscopia Confocal , Modelos Biológicos , Células NIH 3T3 , Ligação Proteica/efeitos dos fármacos , Interferência de RNA , Proteínas Quinases Associadas a Fase S/genética , Ubiquitinação/efeitos dos fármacos
2.
Molecules ; 26(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34770956

RESUMO

The microenvironment for tumor growth and developing metastasis should be essential. This study demonstrated that the hyaluronic acid synthase 3 (HAS3) protein and its enzymatic product hyaluronic acid (HA) encompassed in the subcutaneous extracellular matrix can attenuate the invasion of human breast tumor cells. Decreased HA levels in subcutaneous Has3-KO mouse tissues promoted orthotopic breast cancer (E0771) cell-derived allograft tumor growth. MDA-MB-231 cells premixed with higher concentration HA attenuate tumor growth in xenografted nude mice. Human patient-derived xenotransplantation (PDX) experiments found that HA selected the highly migratory breast cancer cells with CD44 expression accumulated in the tumor/stroma junction. In conclusion, HAS3 and HA were detected in the stroma breast tissues at a high level attenuates effects for induced breast cancer cell death, and inhibit the cancer cells invasion at the initial stage. However, the highly migratory cancer cells were resistant to the HA-mediated effects with unknown mechanisms.


Assuntos
Neoplasias da Mama/metabolismo , Hialuronan Sintases/metabolismo , Tecido Parenquimatoso/metabolismo , Animais , Neoplasias da Mama/patologia , Feminino , Humanos , Hialuronan Sintases/deficiência , Hialuronan Sintases/genética , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Tecido Parenquimatoso/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Células Tumorais Cultivadas
3.
Altern Ther Health Med ; 26(2): 18-22, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29477137

RESUMO

CONTEXT: Taiwanofungus camphoratus is a parasitic mushroom found in the heartwood of Cinnamomum kanehirai and is used as a nutritional supplement. It has an anticancer action, both alone and synergistically with amphotericin B (AmB). OBJECTIVE: The study intended to assess the efficacy of a T camphoratus ethanol extract (TCEE) combined with AmB for patients with metastatic cancer whose cancer did not respond to multiline chemotherapy or who were unwilling to receive chemotherapy. DESIGN: The research team performed a retrospective analysis as a pilot study. SETTING: The study took place at a single hospital (Taipei Medical University Hospital, Taipei, Taiwan). PARTICIPANTS: Participants were 9 patients at the hospital who were terminally ill with metastatic cancer. INTERVENTIONS: The participants had received daily doses of 2-3 g of the TCEE in combination with a weekly dose of 20-25 mg of AmB in 500 cc of 5% glucose water, given intravenously in 4-6 h. OUTCOME MEASURES: Outcome measures included (1) a primary evaluation index measuring the efficacy of the treatment; (2) a measure of tumor burden that was estimated using the response evaluation criteria in solid tumors (RECIST 1.1), (3) a secondary evaluation index measuring survival duration, and (4) safety. RESULTS: The mean treatment time was 54.4 ± 18.3 wk. At the end of the study, 2 patients showed a continued complete response, 1 patient had a continued partial response, and 1 patient showed a stable disease. The other 5 participants had times to progression ranging from 24 to 48 wk, with a mean of 35.6 wk. The mean survival time was 57.8 ± 18.5 wk, and 5 patients were still alive at the end of the study. CONCLUSIONS: For patients whose metastatic cancer did not respond to multiline chemotherapy or who were unwilling to receive chemotherapy, the use of TCEE as an adjuvant therapy to AmB resulted in tumor suppression and a delay in time to disease progression. The preliminary results reported here can be used to guide a future, more extensive clinical study of the combination.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Antrodia/química , Produtos Biológicos/farmacologia , Metástase Neoplásica/patologia , Neoplasias/tratamento farmacológico , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Produtos Biológicos/administração & dosagem , Etanol , Humanos , Neoplasias/patologia , Projetos Piloto , Estudos Retrospectivos , Taiwan , Resultado do Tratamento
4.
Int J Cancer ; 144(3): 615-630, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30097999

RESUMO

The DNA primase polypeptide 1 (PRIM1) is responsible for synthesizing small RNA primers for Okazaki fragments generated during discontinuous DNA replication. PRIM1 mRNA expression levels in breast tumor samples were detected by real-time PCR analysis. Xenografted tumor model was established to study the carcinogenic role of PRIM1 and its potential therapeutic applications. The average PRIM1 mRNA (copy number × 103 /µg) expression was 4.7-fold higher in tumors than in normal tissue (*p = 0.005, n = 254). PRIM1 was detected preferentially at a higher level (>40-fold) in poorly differentiated tumor tissues (n = 46) compared with more highly differentiated tumors tissues (n = 10) (*p = 0.005). Poor overall survival rate was correlated to the estrogen receptor positive (ER+, n = 20) patients with higher PRIM1 expression when compare to the ER- (n = 10) patients (Chi Square test, p = 0.03). Stable expression of PRIM1-siRNA in the ER+ BT-474 cells-xenograft tumors significantly reduced tumor volume in SCID mice (*p = 0.005). The anti-tumoral effects of inotilone isolated from Phellinus linteus was tested and had significant effects on the inhibition of PRIM1 protein expression in ER+ breast cancer cells. In vivo study was performed by administering inotilone (10 mg/kg, twice a week for 6 weeks), which resulted in significantly reduced BT-474-xenografted tumor growth volume compared with control (n =5 per group, *p < 0.05). This study provides evidences for the prognostic effects of PRIM1 with poor overall survival rate in the ER+ patients and will be valuable to test for therapeutic purpose.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , DNA Primase/metabolismo , Animais , Neoplasias da Mama/genética , Linhagem Celular Tumoral , DNA Primase/biossíntese , DNA Primase/genética , Feminino , Furanos/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular , Xenoenxertos , Humanos , Células MCF-7 , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Estrogênio/metabolismo
5.
Toxicol Appl Pharmacol ; 378: 114641, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31254568

RESUMO

Encapsulating peritoneal sclerosis (EPS) is a severe complication of peritoneal dialysis (PD). This disease leads to intestinal obstruction with or without peritonitis. The imbalance between the populations of Th17 and regulatory T (Treg) cells (higher Th17 cells and lower Treg cells) is part of the pathogenesis of EPS formation. We demonstrated that dimethyl sulfoxide (DMSO) effectively inhibited autoimmune diabetes recurrence in the islet transplantation of NOD mice via the induction of the differentiation of Treg cells. In this study, we investigated the therapeutic potential of DMSO in the inhibition of EPS formation by a mouse model. Under DMSO treatment, the thickening of the parietal and visceral peritoneum was significantly reduced. The populations of CD4, CD8, and IFN-γ-producing CD4 and CD8 T cells were decreased. The populations of IL-4-producing CD4 T lymphocytes, IL-10-producing CD4 T lymphocytes, CD4 CD69 T lymphocytes and Treg lymphocytes were increased. The expression levels of the cytokines IFN-γ, IL-17a, TNF-α and IL-23, in ascites, were significantly decreased following the DMSO treatment. Furthermore, the differentiation of Treg cells was induced by DMSO from naïve CD4 T cells in vitro, and these cells were adoptively transferred into the EPS mice and significantly prevented EPS formation, exhibiting a comparable effect to the in vivo DMSO treatment. We also demonstrated that the differentiation of Treg cells by DMSO occurred via the activation of STAT5 by its epigenetic effect, without altering the PI3K-AKT-mTOR or Raf-ERK pathways. Our results demonstrated, for the first time, that in vivo DMSO treatment suppresses EPS formation in a mouse model. Furthermore, the adoptive transfer of Treg cells that were differentiated from naïve CD4 T cells by an in vitro DMSO treatment exhibited a similar effect to the in vivo DMSO treatment for the prevention of EPS formation.


Assuntos
Dimetil Sulfóxido/imunologia , Fibrose Peritoneal/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva/métodos , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Citocinas/imunologia , Diabetes Mellitus Tipo 1/imunologia , Feminino , Interleucina-17/imunologia , Transplante das Ilhotas Pancreáticas/métodos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Fosfatidilinositol 3-Quinases/imunologia , Células Th17/imunologia
6.
Environ Toxicol ; 34(1): 73-82, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30259641

RESUMO

Breast cancer (BC) is the most common cancer affecting women worldwide and has been associated with active tobacco smoking. Low levels of nicotine (Nic) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), have been detected in cases of second-hand smoke (SHS). However, the correlation between SHS and BC risk remains controversial. In this study, we investigated whether the physiological SHS achievable dose of Nic and tobacco specific nitrosamine, NNK act together to induce breast carcinogenesis using an in vitro breast cell carcinogenesis model. Immortalized non-tumorigenic breast epithelial cell line, HBL-100 used for a time-course assay, was exposed to very low levels of either Nic or NNK, or both. The time-course assay consisted of 23 cycles of nitrosamines treatment. In each cycle, HBL-100 cells were exposed to 1pM of Nic and/or 100 femtM of NNK for 48 hours. Cells were passaged every 3 days and harvested after 10, 15, and 23 cycles. Our results demonstrated that the tumorigenicity of HBL-100, defined by soft agar colony forming, proliferation, migration and invasion abilities, was enhanced by co-exposure to physiologically SHS achievable doses of Nic and NNK. In addition, α9-nAChR signaling activation, which plays an important role in cellular proliferation and cell survival, was also observed. Importantly, an increase in stemness properties including the prevalence of CD44+/CD24- cells, increase Nanog expression and mammosphere-forming ability were also observed. Our results indicate that chronic and long term exposure to environmental tobacco smoke, may induce breast cell carcinogenesis even at extremely low doses.


Assuntos
Neoplasias da Mama/induzido quimicamente , Transformação Celular Neoplásica/efeitos dos fármacos , Glândulas Mamárias Humanas/efeitos dos fármacos , Nicotina/toxicidade , Nitrosaminas/toxicidade , Acetilcolina/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinógenos/toxicidade , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Feminino , Humanos , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/fisiologia , Receptores Nicotínicos/genética , Receptores Nicotínicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Fatores de Tempo , Testes de Toxicidade Crônica
7.
BMC Med Educ ; 19(1): 270, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319845

RESUMO

BACKGROUND: Modern nursing requires a broad set of academic and practical skills, and an effective nurse must integrate these skills in a wide range of healthcare contexts. Cultivation of core competencies has recently become a key issue globally in the development of nursing education. To assess the performance of new nurses, this study developed a nursing-specific Mini-Clinical Evaluation Exercise (Mini-CEX) to evaluate the effect of postgraduate year (PGY) nurse training programs in Taiwan. METHODS: A nursing-specific Mini-CEX was developed based on the required core competencies of nurses. Reliability and validity were confirmed in evaluator workshops carried out prior to the administration of the pilot test and final test. Thirty-two PYG trainees were recruited with a supervisor-to-trainee ratio of 1:1.94. Data were collected from February to June 2012 and analyzed using the Kruskal-Wallis test. RESULTS: The 32 PGY trainees scored highest in the "nursing professionalism" dimension and the lowest in the "physical examination" dimension. The overall competency score was satisfactory. The trainee nurses with 19-24 months of experience scored higher than the other two groups in overall performance. CONCLUSION: The results of this research indicate the feasibility of using our Mini-CEX tool to evaluate the competencies of PGY trainees.


Assuntos
Acreditação/organização & administração , Competência Clínica , Educação de Pós-Graduação em Enfermagem/organização & administração , Inquéritos e Questionários , Adulto , Humanos , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Reprodutibilidade dos Testes , Taiwan , Adulto Jovem
8.
Breast Cancer Res Treat ; 172(1): 45-59, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30054830

RESUMO

PURPOSE: Glutathione S-transferase mu 3 (GSTM3) is an enzyme involving in the detoxification of electrophilic compounds by conjugation with glutathione. Higher GSTM3 mRNA levels were reported in patients with ERα-positive breast cancer who received only tamoxifen therapy after surgery. Thus, this study aimed to clarify the oncogenic characteristics of GSTM3 in breast cancer and the mechanism of tamoxifen resistance. METHODS: GSTM3 expression in human breast tumour tissues (n = 227) was analysed by RT-PCR and quantitative PCR. Western blot, promoter activity assays, and chromatin immunoprecipitation (ChIP) assays were used to investigate the mechanism of GSTM3 gene regulation. Hydrogen peroxide (H2O2)-induced cytotoxicity in breast cancer cells was detected by MTT assays and flow cytometry. The oncogenic characteristics of GSTM3 in MCF-7 cells were examined by siRNA knockdown in soft agar assays and a xenograft animal model. RESULTS: GSTM3 mRNA was highly expressed in ER- and HER2-positive breast cancers. Moreover, patients who received adjuvant Herceptin had increased GSTM3 mRNA levels in tumour tissue. Oestrogen-activated GSTM3 gene expression through ERα-mediated recruitment of SP1, EP300, and AP-1 complexes. GSTM3-silenced MCF-7 cells were more sensitive to H2O2, with significantly inhibited proliferation and colony formation abilities. Tamoxifen-resistant (Tam-R) cells lacking GSTM3 showed enhanced sensitivity to H2O2, but this result was contrary to that obtained after short-term tamoxifen exposure. The animal model suggested that GSTM3 silencing might suppress the tumourigenic ability of MCF-7 cells and increase tumour cell apoptosis. CONCLUSIONS: ROS production is one mechanism by which cancer drugs kill tumour cells, and according to our evidence, GSTM3 may play an important role in preventing breast cancer treatment-induced cellular cytotoxicity.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptor alfa de Estrogênio/genética , Glutationa Transferase/genética , Animais , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Estrogênios/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Peróxido de Hidrogênio/toxicidade , Células MCF-7 , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Receptor ErbB-2/genética , Transdução de Sinais/efeitos dos fármacos , Tamoxifeno/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Breast Cancer Res Treat ; 163(1): 131-138, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28205043

RESUMO

BACKGROUND: Multiple common variants identified by genome-wide association studies showed limited evidence of the risk of breast cancer in Taiwan. In this study, we analyzed the breast cancer risk in relation to 13 individual single-nucleotide polymorphisms (SNPs) identified by a GWAS in an Asian population. METHODS: In total, 446 breast cancer patients and 514 healthy controls were recruited for this case-control study. In addition, we developed a polygenic risk score (PRS) including those variants significantly associated with breast cancer risk, and also evaluated the contribution of PRS and clinical risk factors to breast cancer using receiver operating characteristic curve (AUC). RESULTS: Logistic regression results showed that nine individual SNPs were significantly associated with breast cancer risk after multiple testing. Among all SNPs, six variants, namely FGFR2 (rs2981582), HCN1 (rs981782), MAP3K1 (rs889312), TOX3 (rs3803662), ZNF365 (rs10822013), and RAD51B (rs3784099), were selected to create PRS model. A dose-response association was observed between breast cancer risk and the PRS. Women in the highest quartile of PRS had a significantly increased risk compared to women in the lowest quartile (odds ratio 2.26; 95% confidence interval 1.51-3.38). The AUC for a model which contained the PRS in addition to clinical risk factors was 66.52%, whereas that for a model which with established risk factors only was 63.38%. CONCLUSIONS: Our data identified a genetic risk predictor of breast cancer in Taiwanese population and suggest that risk models including PRS and clinical risk factors are useful in discriminating women at high risk of breast cancer from those at low risk.


Assuntos
Povo Asiático/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Estudos de Casos e Controles , Feminino , Estudo de Associação Genômica Ampla , Humanos , Pessoa de Meia-Idade , Taiwan , Adulto Jovem
10.
Ann Surg Oncol ; 24(2): 603-610, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26975740

RESUMO

BACKGROUND: Accumulated evidence indicates that the incidence of early-onset breast cancer has rapidly increased in Taiwan and other Asian compared to Western countries. The mismatch repair (MMR) pathway might be one of the crucial mechanisms of predisposition to early breast cancer. In this study, we explored whether MMR gene polymorphisms contribute to the risk of breast cancer in young women. METHODS: This was a 2-stage case-control study including 737 cases and 719 controls. After eight single nucleotide polymorphisms (SNPs) were genotyped in MMR pathway genes in the stage I study, a promising SNP, MSH2 rs2303425, was selected for validation in the stage II study. A luciferase reporter assay was used to evaluate the transcriptional activity of MSH2. RESULTS: Logistic regression analysis showed that individuals with the MSH2 rs2303425 C/C genotype had a significantly increased risk of breast cancer compared to those with the T/T genotype (adjusted odds ratio 2.0; 95 % confidence interval 1.1-3.8), particularly in early-onset breast cancer patients with the luminal A subtype. The luciferase assay in three cell lines indicated that the MSH2 rs2303425 T/C substitution decreased MSH2 expression, which is consistent with the finding of an association study. CONCLUSIONS: A common variant SNP in MSH2 may contribute to the susceptibility to early-onset breast cancer functionally, particularly for the luminal A subtype.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Proteína 2 Homóloga a MutS/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taiwan/epidemiologia , Adulto Jovem
11.
J Nanobiotechnology ; 14: 11, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26892504

RESUMO

BACKGROUND: Tamoxifen is currently used for the treatment of both early and advanced estrogen receptor (ER) positive breast cancer in pre- and post-menopausal women. However, using tamoxifen routinely to inhibit endogenous or exogenous estrogen effects is occasionally difficult because of its potential side effects. OBJECTIVES: The aim of this study is to design a local drug delivery system to encapsulate tamoxifen for observing their efficacy of skin penetration, drug accumulation and cancer therapy. METHODS: A cationic liposome-PEG-PEI complex (LPPC) was used as a carrier for the encapsulation of tamoxifen and forming 'LPPC/TAM' for transdermal release. The cytotoxicity of LPPC/TAM was analyzed by MTT. The skin penetration, tumor growth inhibition and organ damages were measured in xenograft mice following transdermal treatment. RESULTS: LPPC/TAM had an average size less than 270 nm and a zeta-potential of approximately 40 mV. LPPC/TAM displayed dramatically increased the cytotoxic activity in all breast cancer cells, especially in ER-positive breast cancer cells. In vivo, LPPC drug delivery helped the fluorescent dye penetrating across the skim and accumulating rapidly in tumor area. Administration of LPPC/TAM by transdermal route inhibited about 86 % of tumor growth in mice bearing BT474 tumors. This local treatment of LPPC/TAM did not injury skin and any organs. CONCLUSION: LPPC-delivery system provided a better skin penetration and drug accumulation and therapeutic efficacy. Therefore, LPPC/TAM drug delivery maybe a useful transdermal tool of drugs utilization for breast cancer therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Lipossomos/administração & dosagem , Tamoxifeno/administração & dosagem , Administração Cutânea , Animais , Mama/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Camundongos Nus , Polietilenoglicóis/administração & dosagem , Polietilenoimina/administração & dosagem , Polietilenoimina/análogos & derivados
12.
Ann Surg Oncol ; 22(3): 889-98, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25212833

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is defined by reduced expression of the estrogen receptor, progesterone receptor, and HER2. TNBC is an especially aggressive group of breast cancers with poor prognosis. There are currently no validated molecular targets to effectively treat this disease. Thus, it is necessary to identify effective molecular targets and therapeutic strategies for TNBC patients. METHODS: The expression of HSPA5 in patients with breast cancer was examined by immunohistochemistry. The association of HSPA5 expression with tumor grade and metastatic events in TNBC patients was analyzed using the Oncomine database. The knockdown and overexpression of HSPA5 protein were performed to investigate the effects on E1A-suppressed cell migration/invasion of TNBC using in vitro transwell assays and tumor growth/experimental metastasis studies in animal models. RESULTS: The expression of HSPA5 was positively correlated with high-grade tumors, metastatic events, and poor overall survival in breast cancer patients with TNBC. E1A-inhibited HSPA5 expression suppressed cell migration/invasive ability of TNBC cell lines. Moreover, E1A significantly abolished lung metastases from breast cancer cells by inhibiting HSPA5 expression in a xenograft tumor model. CONCLUSIONS: The overexpression of HSPA5 is critical for high-risk metastasis of breast cancer and TNBC. The results of our study suggest that HSPA5 may be a crucial mediator of E1A-suppressed metastatic ability of breast cancer cells. Thus, E1A may be a potential target for diagnosis and individualized treatment in clinical practice.


Assuntos
Proteínas E1A de Adenovirus/genética , Movimento Celular , Proliferação de Células , Proteínas de Choque Térmico/antagonistas & inibidores , Neoplasias Pulmonares/prevenção & controle , Neoplasias de Mama Triplo Negativas/prevenção & controle , Animais , Apoptose , Chaperona BiP do Retículo Endoplasmático , Feminino , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Camundongos , Camundongos SCID , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Toxicol Appl Pharmacol ; 288(2): 258-68, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26235807

RESUMO

4-Acetylantroquinonol B (4-AAQB), closely related to the better known antroquinonol, is a bioactive isolate of the mycelia of Antrodia camphorata, a Taiwanese mushroom with documented anti-inflammatory, hypoglycemic, vasorelaxative, and recently demonstrated, antiproliferative activity. Based on its traditional use, we hypothesized that 4-AAQB may play an active role in the suppression of cellular transformation, tumor aggression and progression, as well as chemoresistance in colorectal carcinoma (CRC). In this study, we investigated the antiproliferative role of 4-AAQB and its underlying molecular mechanism. We also compared its anticancer therapeutic potential with that of antroquinonol and the CRC combination chemotherapy of choice - folinic acid, fluorouracil and oxaliplatin (FOLFOX). Our results showed that 4-AAQB was most effective in inhibiting tumor proliferation, suppressing tumor growth and attenuating stemness-related chemoresistance. 4-AAQB negatively regulates vital oncogenic and stem cell maintenance signal transduction pathways, including the Lgr5/Wnt/ß-catenin, JAK-STAT, and non-transmembrane receptor tyrosine kinase signaling pathways, as well as inducing a dose-dependent downregulation of ALDH and other stemness related factors. These results were validated in vivo, with animal studies showing 4-AAQB possessed comparable tumor-shrinking ability as FOLFOX and potentiates ability of the later to reduce tumor size. Thus, 4-AAQB, a novel small molecule, projects as a potent therapeutic agent for monotherapy or as a component of standard combination chemotherapy.


Assuntos
4-Butirolactona/análogos & derivados , Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Cicloexanonas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , 4-Butirolactona/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Leucovorina/farmacologia , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Compostos Organoplatínicos/farmacologia , Fenótipo , Transdução de Sinais/efeitos dos fármacos , Esferoides Celulares , Fatores de Tempo , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Carcinogenesis ; 35(11): 2520-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25142973

RESUMO

Previous studies indicated that smoking exposure is associated with an increased risk of breast cancer, and α9-nicotine acetylcholine receptors (α9-nAChRs) are involved in breast tumorigenesis. However, no studies have explored the joint effect of α9-nAChRs (CHRNA9) genes and cigarette smoking exposure on breast cancer risk. A case-control study was conducted on 737 breast cancer patients and 719 age-matched healthy controls. Three single-nucleotide polymorphisms (SNPs) of CHRNA9 located in the promoter region were genotyped and compared between cases and controls to identify those SNPs associated with breast cancer susceptibility. A dual-luciferase reporter assay was used to analyze the promoter activities of these SNPs of the CHRNA9 gene. After a Bonferroni correction, the G allele of the CHRNA9 rs7329797 SNP was significantly associated with an increased risk of developing breast cancer compared with A/A genotype carriers (odds ratio, 1.8; 95% confidence interval, 1.2-2.6). A multiplicative interaction between passive smoking exposure and the CHRNA9 rs73229797 SNP on the risk of breast malignancy was observed. A functional assay further showed that rs73229797 was associated with increased promoter activity of the CHRNA9 gene. Our findings support a significant interaction effect existing between the CHRNA9 gene and smoking exposure on the risk of breast cancer development.


Assuntos
Neoplasias da Mama/genética , Estudos de Associação Genética , Receptores Nicotínicos/genética , Fumar/genética , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Fatores de Risco , Fumar/efeitos adversos , Taiwan
15.
Ann Rheum Dis ; 73(9): 1646-51, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23740232

RESUMO

OBJECTIVES: To investigate the postoperative adverse outcomes among surgical patients with preoperative systemic lupus erythematosus (SLE) in a nationwide population-based study. METHODS: We used Taiwan's National Health Insurance Research Database to identify 4321 surgical inpatients with SLE and 17 284 sex- and age-matched controls receiving major surgery. Sociodemographic characteristics, preoperative comorbidities, postoperative 30-day in-hospital major complications and mortality were analysed among surgical patients with and without SLE. RESULTS: Surgical patients with SLE had a higher prevalence of preoperative coexisting medical conditions and postoperative major complications. The OR of 30-day postoperative mortality for surgical patients with SLE was 1.71 (95% CI 1.09 to 2.67) after adjustment. Surgical patients who had received more recent (within 6 months) preoperative SLE-related inpatient care had higher risks of 30-day postoperative acute renal failure (OR=7.23, 95% CI 4.52 to 11.6), pneumonia (OR=2.60, 95% CI 1.82 to 3.72), pulmonary embolism (OR=4.86, 95% CI 1.20 to 19.7), septicaemia (OR=3.43, 95% CI 2.48 to 4.74), stroke (OR=2.01, 95% CI 1.38 to 2.92), overall complications (OR=2.30, 95% CI 1.89 to 2.80) and 30-day postoperative mortality (OR=2.39, 95% CI 1.28 to 4.45) than surgical patients without SLE. SLE-related preoperative steroid injections showed a dose-dependent relationship with postoperative complications and mortality. CONCLUSIONS: SLE significantly increased the risks of surgical patients for overall major complications and mortality after major surgery. Our findings demonstrated the need for integrated care and revised protocols for perioperative management to improve outcomes for surgical patients with SLE.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Complicações Pós-Operatórias/epidemiologia , Adulto , Distribuição por Idade , Idoso , Estudos de Casos e Controles , Comorbidade , Feminino , Glucocorticoides/efeitos adversos , Glucocorticoides/uso terapêutico , Mortalidade Hospitalar , Hospitalização/estatística & dados numéricos , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Medição de Risco/métodos , Distribuição por Sexo , Taiwan/epidemiologia , Adulto Jovem
16.
Ann Surg Oncol ; 21 Suppl 4: S767-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25212831

RESUMO

BACKGROUND: Vascular endothelial growth factor-C (VEGF-C) plays an important role during cancer progression and metastasis through activation of VEGF receptors. However, the role of VEGF-C in esophageal squamous cell carcinoma (ESCC) remains unclear. METHODS: The expression of VEGF-C in advanced stages of esophageal cancer was examined by immunohistochemistry and its expression was correlated with the protein level of cortactin (CTTN) by Western blot. Knockdown and overexpression of the CTTN protein were respectively performed to investigate the effects on VEGF-C-enhanced ESCC migration/invasion by in vitro transwell assay, cell tracing assay, and tumor growth/experimental metastasis in animal models. RESULTS: The expression of VEGF-C was positively correlated with tumor status and poor clinical prognosis in patient with esophageal cancer. VEGF-C-upregulated CTTN expression contributed the migration/invasive abilities of ESCC cell lines through Src-mediated downregulation of miR-326. Moreover, knockdown of CTTN expression significantly abolished VEGF-C-induced tumor growth and experimental lung metastasis in vivo. CONCLUSIONS: Upregulation of CTTN is critical for VEGF-C-mediated tumor growth and metastasis of ESCC. These finding suggest that VEGF-C upregulated CTTN expression through Src-mediated downregulation of miR-326. CTTN may be a crucial mediator of VEGF-C-involved ESCC metastasis, which provides a potential target for diagnosis and individualized treatment in clinical practice.


Assuntos
Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/genética , Cortactina/análise , Cortactina/genética , Neoplasias Esofágicas/química , Neoplasias Esofágicas/genética , Neoplasias Pulmonares/genética , Fator C de Crescimento do Endotélio Vascular/análise , Animais , Carcinoma de Células Escamosas/secundário , Linhagem Celular Tumoral , Movimento Celular , Rastreamento de Células , Cortactina/metabolismo , Regulação para Baixo , Neoplasias Esofágicas/patologia , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/secundário , Camundongos SCID , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/genética , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Transdução de Sinais/genética , Transfecção , Regulação para Cima , Fator C de Crescimento do Endotélio Vascular/metabolismo
17.
Tumour Biol ; 35(1): 195-204, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23922175

RESUMO

Glucose-regulated protein 78 (GRP78) plays an essential role in embryonic development and in the progression and therapeutic resistance of many cancers. However, little is known about the function of GRP78 in hormone-independent prostate cancer. Here, we found that the expression levels of GRP78 were higher in PC-3 cells than in DU-145 cells. When the expression of GRP78 was silenced using a GRP78-specific small interfering RNA in PC-3 cells, the growth rate and adhesive ability were reduced. Cell migration was dramatically decreased in GRP78-depleted cells. Dissection of the involved signal pathways revealed that maspin expression was upregulated after silencing GRP78 expression. The upregulation of maspin and downregulation of COX-2 may cause the decrease in cell proliferation and migration observed after silencing GRP78 expression. Silencing GRP78 expression may suppress the proliferation, adhesion, and migration of prostate cancer cells via maspin and COX-2 regulation.


Assuntos
Ciclo-Oxigenase 2/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Serpinas/genética , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Progressão da Doença , Chaperona BiP do Retículo Endoplasmático , Inativação Gênica , Proteínas de Choque Térmico/metabolismo , Humanos , Masculino , Metástase Neoplásica , Neoplasias da Próstata/metabolismo
18.
Tumour Biol ; 35(7): 7147-53, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24763827

RESUMO

Several previous studies have investigated the association between the SULT1A1 Arg213His polymorphism and the risk of bladder cancer in various populations. However, these results remain inconsistent. Therefore, we performed this meta-analysis to evaluate the relationship between the SULT1A1 Arg213His polymorphism and the risk of bladder cancer. An extensive literature search was performed to identify all eligible studies regarding this association. The odds ratios (ORs) with 95 % confidence intervals (CIs) were used to estimate the strength of risk under fixed and random effects models. We identified and included eight case-control studies including 2,036 cases and 2,273 controls. No significant association was found between the SULT1A1 Arg213His polymorphism and the risk of bladder cancer under the dominant model; however, those with the SULT1A1 Arg/Arg genotype had a significantly increased risk (OR = 1.218, 95 % CI = 1.067-1.392, P = 0.0044) under the recessive model. In the subgroup analysis of ethnicity, a significant association was observed in Caucasians under the recessive model (OR = 1.269, 95 % CI = 1.069-1.506, P = 0.007). Furthermore, an increased risk of bladder cancer was observed between the Arg213His polymorphism and never smokers in the recessive model (OR = 1.428, 95 % CI = 1.079-1.890, P = 0.013). The results of this meta-analysis indicate that the SULT1A1 Arg213His polymorphism is associated with the risk bladder cancer under a recessive model; however, a possibly higher risk for Caucasians with the Arg/Arg genotype and never smokers needs further investigation.


Assuntos
Arilsulfotransferase/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Neoplasias da Bexiga Urinária/genética , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fumar/efeitos adversos , Neoplasias da Bexiga Urinária/patologia
19.
Tumour Biol ; 35(2): 1581-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24101191

RESUMO

Metastasis is the most life-threatening complication in all cancers. The chemokine receptor 4 (CXCR4) is expressed at high levels in many breast-cancer tumors and may modulate metastasis. We compared the time-to-metastasis and the sites of metastasis between breast-cancer tumors expressing CXCR4 at high or low levels. We enrolled 191 early breast cancer patients in our study. The expression of CXCR4 was evaluated using immunohistochemical staining, and the patients were divided into low-level (CXCR4-) and high-level (CXCR4+) CXCR4 expression groups. Associations between the patients' level of CXCR4 expression and their basic clinical characteristics, time-to-metastasis, and metastatic sites were examined using a Cox proportional-hazards regression model. A total of 107 CXCR4+ patients (56 %) were identified. No statistical differences were evident in basic characteristics between the CXCR4+ and CXCR4- groups. The CXCR4+ group had a higher incidence of distant metastasis during the first year (10.3 % versus 1.1 %, P = 0.009) and shorter event-free survival (17.43 months versus 27.5 months, P = 0.026) than those of the CXCR4- group. The CXCR4+ group also had a higher incidence of bone metastasis (P = 0.008) than the CXCR4- group. No significant difference in metastasis sites in other organs was observed between the two groups. A high level of CXCR4 expression in breast cancer is associated with early distant and bone metastases. The CXCR4+ phenotype may be a useful predictor for the prevention of early treatment failure and bone metastasis in breast cancer patients. This retrospective study shows that a high expression of CXCR4 in breast cancer is associated with earlier distant metastasis and bone metastasis in breast cancer.


Assuntos
Neoplasias da Mama/genética , Estudos de Associação Genética , Receptores CXCR4/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Modelos de Riscos Proporcionais
20.
J Biomed Sci ; 21: 78, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25135473

RESUMO

BACKGROUND: The green fluorescence protein (GFP)-associated fluorescence method and the luciferase-associated bioluminescence method are the two major methods for IVIS imaging system to investigate the bacterial infection in animal models. The aim of this study was to evaluate the infection route of Gram-negative bacteria carrying a stable and broad range of conjugative bioluminescence plasmid pSE-Lux1 in a mouse model. RESULTS: Both encapsulated and non-encapsulated Gram-negative bacteria were used as hosts to evaluate conjugation efficiency and plasmid stability of pSE-Lux1, a recombinant of pSE34 and luxABCDE operon. The plasmid conjugation efficiencies of pSE-Lux1 ranged from 10⁻³ to 10⁻7 in various Gram-negative bacteria. Plasmid pSE-Lux1 maintained in Escherichia coli, Klebsiella pneumoniae, and Salmonella enterica serovars Choleraesues (abbreviated S. Choleraesuis) and Typhimurium (S. Typhimurium), than in Acinetobacter baumannii and Serratia marcescens, was shown to be of better stability for at least four days. To investigate systemic bacterial infections, K. pneumoniae strain CG354 was intravenously injected, and then was clearly observed to be non-pathogenic to Balb/c mice for a long-term bioluminescence monitoring for 6 days. For examining dynamic distributions of gastrointestinal tract infection, the invasion protein SipB-deficient mutant OU5045△sipB and OU5046△sipB of S. serovar Typhimurium constructed in this study, compared to wild-type strain OU5045 and its virulence plasmid-less strain OU5046, were of less virulence to mice. CONCLUSIONS: This is the first study to evaluate the conjugative and stable bioluminescence vehicle system of pSE-Lux1 in a wide range of Gram-negative bacteria, a system that can provide a useful reporter approach to trace systemic and gastrointestinal bacterial infections in a mouse model.


Assuntos
Bactérias Gram-Negativas , Infecções por Bactérias Gram-Negativas , Proteínas de Fluorescência Verde , Medições Luminescentes , Imagem Molecular , Plasmídeos , Animais , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/patologia , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Camundongos , Camundongos Endogâmicos BALB C
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