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1.
Hong Kong Med J ; 30(2): 147-162, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590158

RESUMO

This project was undertaken to develop the first set of consensus statements regarding the management of pancreatic ductal adenocarcinoma (PDAC) in Hong Kong, with the goal of providing guidance to local clinicians. A multidisciplinary panel of experts discussed issues surrounding current PDAC management and reviewed evidence gathered in the local context to propose treatment recommendations. The experts used the Delphi approach to finalise management recommendations. Consensus was defined as ≥80% acceptance among all expert panel members. Thirty-nine consensus statements were established. These statements cover all aspects of PDAC management, including diagnosis, resectability criteria, treatment modalities according to resectability, personalised management based on molecular profiling, palliative care, and supportive care. This project fulfils the need for guidance regarding PDAC management in Hong Kong. To assist clinicians with treatment decisions based on varying levels of evidence and clinical experience, treatment options are listed in several consensus statements.

2.
Lung ; 199(6): 597-602, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34797407

RESUMO

PURPOSE: Gastro-oesophageal reflux disease (GORD) is commonly thought to play an important role in chronic cough and patients are often empirically treated with acid suppression therapy. We sought to investigate the response rate to acid suppression treatment in patients with and without heartburn attending two specialist cough clinics. METHODS: A retrospective review of 558 consecutive patients referred to two specialist cough clinics was performed (UK and USA). Patients who were treated with acid suppression were included and their documented response to treatment was collected. Binary logistic regression was used to ascertain the value of reported heartburn in predicting the response of chronic cough to acid suppression therapy. RESULTS: Of 558 consecutive referrals, 238 patients were excluded due to missing data or cough duration of < 8 weeks. The remaining 320 patients were predominantly female (76%), with mean age 61 yrs (± 13) and 96.8% non-smokers, with chronic cough for 36 (18-117) months. Of 72 patients with heartburn, 20 (28%) noted improvement in their cough with acid suppression, whereas of 248 without heartburn, only 35 (14%) responded. Patients reporting heartburn were 2.7 (95% C.I. 1.3-5.6) times more likely to respond to acid suppression therapy (p = 0.007). CONCLUSION: In specialist cough clinics, few patients report a response of their chronic cough to acid suppression therapy. Nonetheless, heartburn is a useful predictor substantially increasing the likelihood of benefit.


Assuntos
Refluxo Gastroesofágico , Azia , Doença Crônica , Tosse/tratamento farmacológico , Feminino , Refluxo Gastroesofágico/complicações , Refluxo Gastroesofágico/tratamento farmacológico , Azia/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
6.
Diabet Med ; 35(7): 929-936, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29633347

RESUMO

AIM: We developed and implemented a national audit and benchmarking programme to describe the clinical status of people with diabetes attending specialist diabetes services in Australia. METHODS: The Australian National Diabetes Information Audit and Benchmarking (ANDIAB) initiative was established as a quality audit activity. De-identified data on demographic, clinical, biochemical and outcome items were collected from specialist diabetes services across Australia to provide cross-sectional data on people with diabetes attending specialist centres at least biennially during the years 1998 to 2011. RESULTS: In total, 38 155 sets of data were collected over the eight ANDIAB audits. Each ANDIAB audit achieved its primary objective to collect, collate, analyse, audit and report clinical diabetes data in Australia. Each audit resulted in the production of a pooled data report, as well as individual site reports allowing comparison and benchmarking against other participating sites. CONCLUSIONS: The ANDIAB initiative resulted in the largest cross-sectional national de-identified dataset describing the clinical status of people with diabetes attending specialist diabetes services in Australia. ANDIAB showed that people treated by specialist services had a high burden of diabetes complications. This quality audit activity provided a framework to guide planning of healthcare services.


Assuntos
Benchmarking , Complicações do Diabetes , Diabetes Mellitus/terapia , Dietoterapia , Planejamento em Saúde , Hipoglicemiantes/uso terapêutico , Auditoria Médica , Qualidade da Assistência à Saúde , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/uso terapêutico , Austrália , Estudos Transversais , Bases de Dados Factuais , Conjuntos de Dados como Assunto , Feminino , Humanos , Hipolipemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Neuroscience ; 353: 106-118, 2017 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-28433648

RESUMO

To understand the behavioral consequences of intermittent anticipatory stress resulting from threats without accompanying physiological challenges, we developed a semi-naturalistic rodent housing and foraging environment that can include threats that are unpredictable in timing. Behavior is automatically recorded while rats forage for food or water. Over three weeks, the threats have been shown to elicit risk assessment behaviors, increase defensive burying and increase adrenal gland weight. To identify brain regions activated by this manipulation, we measured cytochrome c oxidase (COX), which is tightly coupled to neural activity. Adolescent male Sprague-Dawley rats were randomly assigned to control (CT) or unpredictable threat/stress (ST) housing conditions consisting of two tub cages, one with food and another with water, separated by a tunnel. Over three weeks (P31-P52), the ST group received randomly timed (probability of 0.25), simultaneous presentations of ferret odor, an abrupt light, and sound at the center of the tunnel. The ST group had consistently fewer tunnel crossings than the CT group, but similar body weights. Group differences in COX activity were detected in regions implicated in the control of defensive burying. There was an increase in COX activity in the hypothalamic premammillary dorsal nucleus (PMD) and lateral septum (LS), whereas a decrease was observed in the periaqueductal gray (PAG) and CA3 region of the hippocampus. There were no significant differences in the anterior cingulate cortex, prefrontal cortex, striatum or motor cortex. The sites with changes in metabolic capacity are candidates for the sites of plasticity that may underlie the behavioral adaptations to intermittent threats.


Assuntos
Comportamento Animal , Encéfalo/enzimologia , Estresse Psicológico/metabolismo , Animais , Comportamento Apetitivo , Encéfalo/fisiopatologia , Ingestão de Alimentos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Masculino , Ratos Sprague-Dawley , Análise e Desempenho de Tarefas
9.
Oncogene ; 36(24): 3397-3405, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27819675

RESUMO

Intestinal epithelial stem cells are highly sensitive to differentiation induced by endoplasmic reticulum (ER) stress. Colorectal cancer develops from mutated intestinal epithelial stem cells. The most frequent initiating mutation occurs in Apc, which results in hyperactivated Wnt signalling. This causes hyperproliferation and reduced sensitivity to chemotherapy, but whether these mutated stem cells are sensitive to ER stress induced differentiation remains unknown. Here we examined this by generating mice in which both Apc and ER stress repressor chaperone Grp78 can be conditionally deleted from the intestinal epithelium. For molecular studies, we used intestinal organoids derived from these mice. Homozygous loss of Apc alone resulted in crypt elongation, activation of the Wnt signature and accumulation of intestinal epithelial stem cells, as expected. This phenotype was however completely rescued on activation of ER stress by additional deletion of Grp78. In these Apc-Grp78 double mutant animals, stem cells were rapidly lost and repopulation occurred by non-mutant cells that had escaped recombination, suggesting that Apc-Grp78 double mutant stem cells had lost self-renewal capacity. Although in Apc-Grp78 double mutant mice the Wnt signature was lost, these intestines exhibited ubiquitous epithelial presence of nuclear ß-catenin. This suggests that ER stress interferes with Wnt signalling downstream of nuclear ß-catenin. In conclusion, our findings indicate that ER stress signalling results in loss of Apc mutated intestinal epithelial stem cells by interference with the Wnt signature. In contrast to many known inhibitors of Wnt signalling, ER stress acts downstream of ß-catenin. Therefore, ER stress poses a promising target in colorectal cancers, which develop as a result of Wnt activating mutations.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Neoplasias do Colo/genética , Células Epiteliais/citologia , Proteínas de Choque Térmico/genética , Células-Tronco/citologia , Animais , Diferenciação Celular , Proliferação de Células , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático , Células Epiteliais/metabolismo , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Células-Tronco/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo
10.
Curr Oncol ; 23(5): 298-303, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27803593

RESUMO

INTRODUCTION: BRCA mutation testing allows index patients and their families to be provided with appropriate cancer risk-reduction strategies. Because of the low prevalence of BRCA mutations in unselected breast cancer patients and the high cost of genetic testing, it is important to identify the subset of women who are likely to carry BRCA mutations. In the present study, we examined the association between BRCA1/2 germline mutations and the immunohistochemical features of breast cancer. METHODS: In a retrospective review of 498 breast cancer patients who had undergone BRCA testing at Seoul National University Bundang Hospital between July 2003 and September 2012, we gathered immunohistochemical information on estrogen receptor (er), progesterone receptor (pr), her2 (human epidermal growth factor receptor 2), cytokeratin 5/6, egfr (epidermal growth factor receptor), and p53 status. RESULTS: Among the 411 patients eligible for the study, 50 (12.2%) had germline mutations in BRCA1 or BRCA2. Of the 93 patients with triple-negative breast cancer (tnbc), 25 with BRCA1/2 mutations were identified (BRCA1, 20.4%; BRCA2, 6.5%). On univariate analysis, er, pr, cytokeratin 5/6, egfr, and tnbc were found to be related to BRCA1 mutations, but on multivariate analysis, only tnbc was significantly associated with BRCA1 mutations. Among patients with early-onset breast cancer or with a family history of breast or ovarian cancer, BRCA1 mutations were significantly more prevalent in the tnbc group than in the non-tnbc group. CONCLUSIONS: In the present study, tnbc was the only independent predictor of BRCA1 mutation in patients at high risk of hereditary breast and ovarian cancers. Other histologic features of basal-like breast cancer did not improve the estimate of BRCA1 mutation risk.

11.
J Physiol ; 594(20): 5823-5837, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-26913808

RESUMO

Brain Cav 1.2 and Cav 1.3 L-type Ca2+ channels play key physiological roles in various neuronal processes that contribute to brain function. Genetic studies have recently identified CACNA1C as a candidate risk gene for bipolar disorder (BD), schizophrenia (SCZ), major depressive disorder (MDD) and autism spectrum disorder (ASD), and CACNA1D for BD and ASD, suggesting a contribution of Cav 1.2 and Cav 1.3 Ca2+ signalling to the pathophysiology of neuropsychiatric disorders. Once considered sole clinical entities, it is now clear that BD, SCZ, MDD and ASD share common phenotypic features, most likely due to overlapping neurocircuitry and common molecular mechanisms. A major future challenge lies in translating the human genetic findings to pathological mechanisms that are translatable back to the patient. One approach for tackling such a daunting scientific endeavour for complex behaviour-based neuropsychiatric disorders is to examine intermediate biological phenotypes in the context of endophenotypes within distinct behavioural domains. This will better allow us to integrate findings from genes to behaviour across species, and improve the chances of translating preclinical findings to clinical practice.


Assuntos
Afeto/fisiologia , Comportamento Aditivo/metabolismo , Comportamento Aditivo/fisiopatologia , Canais de Cálcio Tipo L/metabolismo , Cognição/fisiologia , Animais , Endofenótipos/metabolismo , Humanos
12.
Oncogene ; 34(43): 5418-26, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25684138

RESUMO

Rates of the most common gynecologic cancer, endometrioid adenocarcinoma (EAC), continue to rise, mirroring the global epidemic of obesity, a well-known EAC risk factor. Thus, identifying novel molecular targets to prevent and/or mitigate EAC is imperative. The prevalent Type 1 EAC commonly harbors loss of the tumor suppressor, Pten, leading to AKT activation. The major endoplasmic reticulum (ER) chaperone, GRP78, is a potent pro-survival protein to maintain ER homeostasis, and as a cell surface protein, is known to regulate the phosphatidylinositol 3-kinase (PI3K)/AKT pathway. To determine whether targeting GRP78 could suppress EAC development, we created a conditional knockout mouse model using progesterone receptor-Cre-recombinase to achieve Pten and Grp78 (cPten(f/f)Grp78(f/f)) deletion in the endometrial epithelium. Mice with a single Pten (cPten(f/f)) deletion developed well-differentiated EAC by 4 weeks. In contrast, no cPten(f/f)Grp78(f/f) mice developed EAC, even after more than 8 months of observation. Histologic examination of uteri from cPten(f/f)Grp78(f/f) mice also revealed no complex atypical hyperplasia, a well-established EAC precursor. These histologic observations among the cPten(f/f)Grp78(f/f) murine uteri also corresponded to abrogation of AKT activation within the endometrium. We further observed that GRP78 co-localized with activated AKT on the surface of EAC, thus providing an opportunity for therapeutic targeting. Consistent with previous findings that cell surface GRP78 is an upstream regulator of PI3K/AKT signaling, we show here that in vivo short-term systemic treatment with a highly specific monoclonal antibody against GRP78 suppressed AKT activation and increased apoptosis in the cPten(f/f) tumors. Collectively, these findings present GRP78-targeting therapy as an efficacious therapeutic option for EAC.


Assuntos
Anticorpos Monoclonais/farmacologia , Carcinogênese/efeitos dos fármacos , Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Endometrioide/metabolismo , Proteínas de Choque Térmico/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinogênese/metabolismo , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Chaperonas Moleculares/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais/efeitos dos fármacos
13.
Neurogastroenterol Motil ; 27(3): 431-42, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25628004

RESUMO

BACKGROUND: Gastroesophageal reflux plays an important role in chronic cough (CC). Whether disturbed esophageal motility contributes to increased esophageal reflux exposure or interferes with swallowed bolus clearance is unclear. This study used high resolution esophageal manometry and impedance (HRIM) together with Chicago Classification, and 24-h impedance pH (MII/pH) to address these questions in patients with CC compared with heartburn (HB). METHODS: A retrospective review of 32 patients with CC (mean age 57 [95% CI: 52-62] years) and 32 patients with symptoms of HB (55 [52-62] years) referred for HRIM and MII/pH between September 2012 and September 2013 was undertaken. KEY RESULTS: Weak peristalsis with large breaks (WPLBs) was observed in 34% of CC patients compared with only 12% of HB patients (p = 0.027). Pathological acid exposure time (AET) was identified in 81% of CC patients with WPLBs compared with 29% without (p = 0.011). Increased AET was associated with prolonged clearance time of refluxed events (p = 0.006) rather than increased number of events. AET correlated with the percentage of peristaltic events with large breaks in CC (ρ = 0.467, p = 0.007). Similar data were obtained for total bolus (acid and non-acid) exposure time. Only one of the CC patients with WPLBs exhibited complete bolus transit (CBT) on swallowing compared with 81% without WPLBs (p < 0.001). Moreover, the percentage of peristaltic events associated with CBT negatively correlated with the percentage of peristaltic events with large breaks (r = -0.653, p < 0.001) in CC. CONCLUSIONS & INFERENCES: One-third of CC patients exhibit WPLBs, which directly impacts on clearance of refluxed events and bolus's swallowed. These observations may have important implications for esophageal-bronchial interaction in CC.


Assuntos
Tosse/complicações , Tosse/fisiopatologia , Refluxo Gastroesofágico/complicações , Peristaltismo , Doença Crônica , Tosse/epidemiologia , Monitoramento do pH Esofágico , Feminino , Azia/complicações , Azia/fisiopatologia , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Estudos Retrospectivos
14.
Oncogene ; 33(42): 4997-5005, 2014 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-24141775

RESUMO

Glucose-regulated protein 78 (GRP78), a molecular chaperone widely elevated in human cancers, is critical for endoplasmic reticulum (ER) protein folding, stress signaling and PI3K/AKT activation. Genetic knockout models of GRP78 revealed that GRP78 maintains homeostasis of metabolic organs, including liver, pancreas and adipose tissues. Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) are the most common liver cancers. There is a lack of effective therapeutics for HCC and CC, highlighting the need to further understand liver tumorigenic mechanisms. PTEN (phosphatase and tenson homolog deleted on chromosome 10), a tumor suppressor that antagonizes the PI3K/AKT pathway, is inactivated in a wide range of tumors, including 40-50% of human liver cancers. To elucidate the role of GRP78 in liver cancer, we created a mouse model with biallelic liver-specific deletion of Pten and Grp78 mediated by Albumin-Cre-recombinase (cP(f/f)78(f/f)). Interestingly, in contrast to PTEN, deletion of GRP78 was progressive but incomplete. At 3 months, cP(f/f)78(f/f) livers showed hepatomegaly, activation of lipogenic genes, exacerbated steatosis and liver injury, implying that GRP78 protects the liver against PTEN-null-mediated pathogenesis. Furthermore, in response to liver injury, we observed increased proliferation and expansion of bile duct and liver progenitor cells in cP(f/f)78(f/f) livers. Strikingly, bile duct cells in cP(f/f)78(f/f) livers maintained wild-type (WT) GRP78 level, whereas adjacent areas showed GRP78 reduction. Analysis of signaling pathways revealed selective JNK activation, ß-catenin downregulation, along with PDGFRα upregulation, which was unique to cP(f/f)78(f/f) livers at 6 months. Development of both HCC and CC was accelerated and was evident in cP(f/f)78(f/f) livers at 8-9 months, coinciding with intense GRP78 expression in the cancer lesions, and GRP78 expression in adjacent normal areas reverted back to the WT level. In contrast, c78(f/f) livers showed no malignancy even at 14 months. These studies reveal that GRP78 is a novel regulator for PTEN-loss-mediated liver injury and cancer progression.


Assuntos
Fígado Gorduroso/genética , Proteínas de Choque Térmico/fisiologia , Neoplasias Hepáticas Experimentais/genética , PTEN Fosfo-Hidrolase/genética , Animais , Neoplasias dos Ductos Biliares/enzimologia , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Proliferação de Células , Colangiocarcinoma/enzimologia , Colangiocarcinoma/genética , Progressão da Doença , Chaperona BiP do Retículo Endoplasmático , Fígado Gorduroso/enzimologia , Deleção de Genes , Humanos , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas Experimentais/enzimologia , Masculino , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Células-Tronco/fisiologia
15.
Eur J Clin Nutr ; 67(7): 786-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23778782

RESUMO

OBJECTIVE: Incorporation of seeds into food products may attenuate postprandial glycemia. Whether these should be consumed as whole or in ground form is not known. SUBJECTS/METHODS: Using an acute, randomized controlled crossover design, the glycemic response of 13 healthy participants (6M:7F; 25.4±2.6 kg/m(2)) was studied on nine separate occasions. Test meals consisted of 7, 15 or 24 g of whole or ground Salba baked into white bread, and three control breads matched for energy, and macronutrient profile. Capillary blood samples were collected at fasting and over 2 h post consumption. RESULTS: A significant effect of dose (P=0.04), but no effect of form (P=0.74) or dose-form interaction (P=0.98) was found. No adverse events were reported. CONCLUSION: This study demonstrates that both ground and whole Salba are equally effective in attenuating blood glucose levels in a dose-dependent manner when incorporated into bread. Flexibility in the use of either the ground or whole seed may increase the ease of incorporation and acceptability as a dietary supplement.


Assuntos
Glicemia/análise , Suplementos Nutricionais , Período Pós-Prandial/efeitos dos fármacos , Salvia , Sementes , Área Sob a Curva , Índice de Massa Corporal , Pão , Estudos Cross-Over , Relação Dose-Resposta a Droga , Feminino , Índice Glicêmico/efeitos dos fármacos , Voluntários Saudáveis , Humanos , Masculino
16.
Oncogene ; 32(7): 805-18, 2013 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22508478

RESUMO

Cancer progression is characterized by rapidly proliferating cancer cells that are in need of increased protein synthesis. Therefore, enhanced endoplasmic reticulum (ER) activity is required to facilitate the folding, assembly and transportation of membrane and secretory proteins. These functions are carried out by ER chaperones. It is now becoming clear that the ER chaperones have critical functions outside of simply facilitating protein folding. For example, cancer progression requires glucose regulated protein (GRP) 78 for cancer cell survival and proliferation, as well as angiogenesis in the microenvironment. GRP78 can translocate to the cell surface acting as a receptor regulating oncogenic signaling and cell viability. Calreticulin, another ER chaperone, can translocate to the cell surface of apoptotic cancer cells and induce immunogenic cancer cell death and antitumor responses in vivo. Tumor-secreted GRP94 has been shown to elicit antitumor immune responses when used as antitumor vaccines. Protein disulfide isomerase is another ER chaperone that demonstrates pro-oncogenic and pro-survival functions. Because of intrinsic alterations of cellular metabolism and extrinsic factors in the tumor microenvironment, cancer cells are under ER stress, and they respond to this stress by activating the unfolded protein response (UPR). Depending on the severity and duration of ER stress, the signaling branches of the UPR can activate adaptive and pro-survival signals, or induce apoptotic cell death. The protein kinase RNA-like ER kinase signaling branch of the UPR has a dual role in cancer proliferation and survival, and is also required for ER stress-induced autophagy. The activation of the inositol-requiring kinase 1α branch promotes tumorigenesis, cancer cell survival and regulates tumor invasion. In summary, perturbance of ER homeostasis has critical roles in tumorigenesis, and therapeutic modulation of ER chaperones and/or UPR components presents potential antitumor treatments.


Assuntos
Antineoplásicos/uso terapêutico , Transformação Celular Neoplásica/genética , Retículo Endoplasmático/metabolismo , Chaperonas Moleculares/fisiologia , Resposta a Proteínas não Dobradas/fisiologia , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte/fisiologia , Transformação Celular Neoplásica/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/fisiologia , Chaperona BiP do Retículo Endoplasmático , Humanos , Modelos Biológicos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Terapia de Alvo Molecular/métodos , Resposta a Proteínas não Dobradas/genética
17.
Oncogene ; 32(39): 4694-701, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23085757

RESUMO

GRP78, a major endoplasmic reticulum chaperone and signaling regulator, is commonly overexpressed in cancer. Moreover, induction of GRP78 by a variety of anti-cancer drugs, including histone deacetylase inhibitors, confers chemoresistance to cancer, thereby contributing to tumorigenesis. Thus, therapies aimed at decreasing GRP78 levels, which results in the inhibition of tumor cell proliferation and resensitization of tumor cells to chemotherapeutic drugs may hold promise for cancer treatment. Despite advances in our understanding of GRP78 actions, little is known about endogenous inhibitors controlling its expression. As endogenous regulators, microRNAs (miRNAs) play important roles in modulating gene expression; therefore, we sought to identify miRNA(s) that target GRP78, under the hypothesis that these miRNAs may serve as therapeutic agents. Here, we report that three miRNAs (miR-30d, miR-181a, miR-199a-5p) predicted to target GRP78 are down-regulated in prostate, colon and bladder tumors, and human cancer cell lines. We show that in C42B prostate cancer cells, these miRNAs down-regulate GRP78 and induce apoptosis by directly targeting its 3' untranslated region. Importantly, we demonstrate that the three miRNAs act cooperatively to decrease GRP78 levels, suggesting that multiple miRNAs may be required to efficiently control the expression of some genes. In addition, delivery of multiple miRNAs by either transient transfection or lentivirus transduction increased the sensitivity of cancer cells to the histone deacetylase inhibitor, trichostatin A, in C42B, HCT116 and HL-60 cells. Together, our results indicate that the delivery of co-transcribed miRNAs can efficiently suppress GRP78 levels and GRP78-mediated chemoresistance, and suggest that this strategy holds therapeutic potential.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico/biossíntese , MicroRNAs/fisiologia , RNA Mensageiro/fisiologia , Regiões 3' não Traduzidas , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Apoptose , Linhagem Celular Tumoral/efeitos dos fármacos , Linhagem Celular Tumoral/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Chaperona BiP do Retículo Endoplasmático , Genes Reporter , Vetores Genéticos , Células HL-60/efeitos dos fármacos , Células HL-60/metabolismo , Proteínas de Choque Térmico/genética , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Lentivirus/genética , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Neovascularização Patológica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , RNA/farmacologia , RNA Mensageiro/genética , Tapsigargina/farmacologia , Transcrição Gênica , Transfecção , Ensaio Tumoral de Célula-Tronco , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Breast Cancer Res Treat ; 136(1): 209-20, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22965832

RESUMO

Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations, and thus GWAS-identified single nucleotide polymorphisms (SNPs) in one population may not be of significance in another population. In order to explore the role of breast cancer susceptibility variants in a Chinese population of Southern Chinese descent, we analyzed 22 SNPs for 1,191 breast cancer cases and 1,534 female controls. Associations between the SNPs and clinicopathological features were also investigated. In addition, we evaluated the combined effects of associated SNPs by constructing risk models. Eight SNPs were associated with an elevated breast cancer risk. Rs2046210/6q25.1 increased breast cancer risk via an additive model [per-allele odds ratio (OR) = 1.43, 95 % confidence interval (CI) = 1.26-1.62], and was associated with estrogen receptor (ER)-positive (per-allele OR = 1.39, 95 % CI = 1.20-1.61) and ER-negative (per-allele OR = 1.55, 95 % CI = 1.28-1.89) disease. Rs2046210 was also associated with stage 1, stage 2, and stage 3 disease, with per-allele ORs of 1.38 (1.14-1.68), 1.48 (1.25-1.74), and 1.58 (1.28-1.94), respectively. Four SNPs mapped to 10q26.13/FGFR2 were associated with increased breast cancer risk via an additive model with per-allelic risks (95 % CI) of 1.26 (1.12-1.43) at rs1219648, 1.22 (1.07-1.38) at rs2981582, 1.21 (1.07-1.36) at rs2981579, and 1.18 (1.04-1.35) at rs11200014. Variants of rs7696175/TLR1, TLR6, rs13281615/8q24, and rs16886165/MAP3K1 were also associated with increased breast cancer risk, with per-allele ORs (95 % CI) of 1.16 (1.00-1.34), 1.15 (1.02-1.29), and 1.15 (1.01-1.29), respectively. Five SNPs associated with breast cancer risk predominantly among ER-positive tumors (rs2981582/FGFR2, rs4415084/MRPS30, rs1219648/FGFR2, rs2981579/FGFR2, and rs11200014/FGFR2). Among our Chinese population, the risk of developing breast cancer increased by 90 % for those with a combination of 6 or more risk alleles, compared to patients with ≤3 risk alleles.


Assuntos
Neoplasias da Mama , Estudos de Associação Genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , China , Feminino , Loci Gênicos , Predisposição Genética para Doença , Humanos , Desequilíbrio de Ligação , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Fatores de Risco
20.
PLoS One ; 7(6): e39174, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22761733

RESUMO

Cardiac depression in sepsis is associated with the increased morbidity and mortality. Although myofilaments damage, autonomic dysfunction, and apoptosis play roles in sepsis-induced myocardial dysfunction, the underlying mechanism is not clear. All of these possible factors are related to NFκB signaling, which plays the main role in sepsis signaling. Thaliporphine was determined to possess anti-inflammatory and cardioprotective activity by suppressing NFκB signaling in rodents. The purpose of this study is to further prove this protective effect in larger septic animals, and try to find the underlying mechanisms. The systolic and diastolic functions were evaluated in vivo by pressure-volume analysis at different preloads. Both preload-dependent and -independent hemodynamic parameters were performed. Inflammatory factors of whole blood and serum samples were analyzed. Several sepsis-related signaling pathways were also determined at protein level. Changes detected by conductance catheter showed Thaliporphine could recover impaired left ventricular systolic function after 4 hours LPS injection. It could also reverse the LPS induced steeper EDPVR and gentler ESPVR, thus improve Ees, Ea, and PRSW. Thaliporphine may exert this protective effect by decreasing TNFα and caspase3 dependent cell apoptosis, which was consistent with the decreased serum cTnI and LDH concentration. Thaliporphine could protect sepsis-associated myocardial dysfunction in both preload-dependent and -independent ways. It may exert these protective effects by both increase of "good"-PI3K/Akt/mTOR and decrease of "bad"-p38/NFκB pathways, which followed by diminishing TNFα and caspase3 dependent cell apoptosis.


Assuntos
Aporfinas/uso terapêutico , Endotoxemia/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , NF-kappa B/metabolismo , Extratos Vegetais/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Endotoxemia/metabolismo , Masculino , Miócitos Cardíacos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Coelhos , Fator de Necrose Tumoral alfa/metabolismo
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