Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 157
Filtrar
1.
Hong Kong Med J ; 29(4): 324-329, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37424071

RESUMO

INTRODUCTION: Prostate-specific antigen-based screening for prostate cancer reportedly does not improve cancer-specific survival. However, there remain concerns about the increasing incidence of advanced disease at initial presentation. Here, we investigated the incidences and types of complications that occur during the course of disease in patients with metastatic hormone-sensitive prostate cancer (mHSPC). METHODS: This study included 100 consecutive patients who were diagnosed with mHSPC at five hospitals from January 2016 to August 2017. Analyses were conducted using patient data extracted from a prospectively collected database, along with information about complications and readmission obtained from electronic medical records. RESULTS: The median patient age was 74 years and the median serum prostate-specific antigen level at diagnosis was 202.5 ng/mL. Ninety-nine patients received androgen deprivation therapy; 17 of these patients also received chemotherapy. During a mean follow-up period of 32.9 months, 41 patients reported bone pain; of these patients, 21 developed pathologic fractures and eight had cord compression. Twenty-eight patients developed retention of urine; of these patients, 10 (36%) required surgery and 11 (39%) required long-term urethral catheter use. Among 15 patients who developed ureteral obstruction, four (27%) required ureteral stenting and four (27%) required long-term nephrostomy drainage. Other complications included anaemia (41%) and deep vein thrombosis (4%). Fifty-nine (59%) patients had ≥1 unplanned hospital admission during the course of disease; 16% of such patients had >5 episodes of readmission. CONCLUSION: Among patients with mHSPC, 70% experienced disease-related complications and unplanned hospital admissions, which substantially burdened both patients and the healthcare system.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Idoso , Neoplasias da Próstata/complicações , Neoplasias da Próstata/tratamento farmacológico , Antígeno Prostático Específico , Antagonistas de Androgênios/efeitos adversos , Hormônios/uso terapêutico
3.
Phys Rev Lett ; 129(8): 080401, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053678

RESUMO

The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.

5.
Artigo em Chinês | MEDLINE | ID: mdl-35725314

RESUMO

Objective: To determine the characteristics of cervical neuroblastoma and the effect of resection extent on survival and outcomes. Methods: We performed a retrospective review of 32 children with cervical neuroblastoma treated at Beijing Children's Hospital between April 2013 and August 2020. Data were collected from the medical record. The individualized therapy was designed based on staging and risk group. Based on the extent of resection, patients were divided into incomplete and complete resection groups. Event free and overall survival rates were compared between two groups using the Kaplan-Meier method. Results: The ages of patients ranged from 1 month to 81 months, with a median age of 11 months, including 7 males and 15 females. Twenty-nine patients (90.6%) presented with cervical painless mass. The average diameter of the primary tumors was (5.12±1.43) cm. Tumors were located in the parapharyngeal space in 25 cases (78.1%) and in the root of the neck in 7 cases (21.9%). None had MYCN amplification. According to International Neuroblastoma Staging System (INSS), 15 patients (46.9%) were identified as stage 1, 11 patients (34.3%) as stage 2B, 3 patients (9.4%) as stage 3 and 3 patients (9.4%) as stage 4. There were 12 patients (37.5%) at low risk, 17 patients (53.1%) at intermediate risk and 3 patients at high risk according to Children's Oncology Group (COG) risk classification system. All patients underwent tumor resection. Postoperatively Horner's syndrome occurred in 13 patients (40.6%), pneumonia in 9 patients (28.1%), pharyngeal dysfunction in 8 patients (25.0%) and transient hoarseness in 4 patients (12.5%). At a median follow-up of 36.5 months, the overall survival rate was 96.4%, with no significant difference between incomplete and complete resection groups (100.0% vs. 96.3%, χ2=0.19, P=0.667); the event free survival rate was 78.1%, with a significant difference between the two groups (40.0% vs. 85.2%, χ²=6.71, P=0.010). Conclusions: Primary cervical neuroblastoma has a young onset age, mostly in low and medium risk groups, and represents favorable lesions with good outcomes after multidisciplinary therapy. Less aggressive surgery with preservation of important structures is recommended. Complete resection should not be attempted if it would compromise vital structures.


Assuntos
Neuroblastoma , Criança , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Masculino , Estadiamento de Neoplasias , Neuroblastoma/patologia , Neuroblastoma/terapia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida
7.
Clin Oncol (R Coll Radiol) ; 33(11): e469-e481, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34509347

RESUMO

Despite improvements in radiotherapy, radioresistance remains an important clinical challenge. Radioresistance can be mediated through enhanced DNA damage response mechanisms within the tumour or through selective pressures exerted by the tumour microenvironment (TME). The effects of the TME have in recent times gained increased attention, in part due to the success of immune modulating strategies, but also through improved understanding of the downstream effects of hypoxia and dysregulated wound healing processes on mediating radioresistance. Although we have a better appreciation of these molecular mechanisms, efforts to address them through novel combination approaches have been scarce, owing to limitations of photon therapy and concerns over toxicity. At the same time, proton beam therapy (PBT) represents an advancement in radiotherapy technologies. However, early clinical results have been mixed and the clinical strategies around optimal use and patient selection for PBT remain unclear. Here we highlight the role that PBT can play in addressing radioresistance, through better patient selection, and by providing an improved toxicity profile for integration with novel agents. We will also describe the developments around FLASH PBT. Through close examination of its normal tissue-sparing effects, we will highlight how FLASH PBT can facilitate combination strategies to tackle radioresistance by further improving toxicity profiles and by directly mediating the mechanisms of radioresistance.


Assuntos
Neoplasias , Terapia com Prótons , Radioterapia (Especialidade) , Humanos , Neoplasias/radioterapia , Seleção de Pacientes , Microambiente Tumoral
8.
Hong Kong Med J ; 27(2): 127-139, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33879628

RESUMO

Lower urinary tract symptoms (LUTS) are common complaints of adult men. Benign prostatic hyperplasia (BPH) represents the most common underlying cause. As the incidence of BPH increases with age, and pharmacological treatment is a major part of the disease's management, the majority of patients with LUTS are managed by primary care practitioners. There are circumstances in which specialist care by urologists or geriatricians is required, such as failure of medical treatment, adverse effects from medical treatment, or complications from BPH. Referral choices can be confusing to patients and even practitioners in different specialties under such circumstances. There is currently no local consensus about the diagnosis, medical management, or referral mechanism of patients with BPH. A workgroup was formed by members of The Hong Kong Geriatrics Society (HKGS) and the Hong Kong Urological Association (HKUA) to review evidence for the diagnosis and medical treatment of LUTS. A consensus was reached by HKGS and HKUA on an algorithm for the flow of male LUTS care and the use of uroselective alpha blockers, antimuscarinics, beta-3 adrenoceptor agonists, and 5α-reductase inhibitors in the primary care setting. This consensus by HKGS and HKUA provides a new management paradigm of male LUTS.


Assuntos
Geriatria , Sintomas do Trato Urinário Inferior , Adulto , Consenso , Hong Kong/epidemiologia , Humanos , Incidência , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Sintomas do Trato Urinário Inferior/epidemiologia , Sintomas do Trato Urinário Inferior/etiologia , Masculino , Polimedicação
10.
Oncogenesis ; 9(2): 27, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32102990

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

11.
Gynecol Oncol ; 151(1): 117-123, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30100053

RESUMO

OBJECTIVE: Enhanced recovery pathways have been shown to reduce length of stay without increasing readmission or complications in numerous areas of surgery. Uptake of gynecologic oncology ERAS guidelines has been limited. We describe the effect of ERAS guideline implementation in gynecologic oncology on length of stay, patient outcomes, and economic impact for a province-wide single-payer system. METHODS: We compared pre- and post-guideline implementation outcomes in consecutive staging and debulking patients at two centers that provide the majority of surgical gynecologic oncology care in Alberta, Canada between March 2016 and April 2017. Clinical outcomes and compliance were obtained using the ERAS Interactive Audit System. Patients were followed until 30 days after discharge. Negative binomial regression was employed to adjust for patient characteristics. RESULTS: We assessed 152 pre-ERAS and 367 post-ERAS implementation patients. Mean compliance with ERAS care elements increased from 56% to 77.0% after implementation (p < 0.0001). Median length of stay for all surgeries decreased from 4.0 days to 3.0 days post-ERAS (p < 0.0001), which translated to an adjusted LOS decrease of 31.4% (95% CI = [21.7% - 39.9%], p < 0.0001). In medium/high complexity surgery median LOS was reduced by 2.0 days (p = 0.0005). Complications prior to discharge decreased from 53.3% to 36.2% post-ERAS (p = 0.0003). There was no significant difference in readmission (p = 0.6159), complications up to 30 days (p = 0.6274), or mortality (p = 0.3618) between the cohorts. The net cost savings per patient was $956 (95%CI: $162 to $1636). CONCLUSIONS: Systematic implementation of ERAS gynecologic oncology guidelines across a healthcare system improves patient outcomes and saves resources.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Fidelidade a Diretrizes/estatística & dados numéricos , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Assistência Perioperatória/normas , Complicações Pós-Operatórias/epidemiologia , Idoso , Redução de Custos , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Procedimentos Cirúrgicos de Citorredução/economia , Procedimentos Cirúrgicos de Citorredução/métodos , Feminino , Neoplasias dos Genitais Femininos/economia , Procedimentos Cirúrgicos em Ginecologia/economia , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Tempo de Internação/economia , Tempo de Internação/estatística & dados numéricos , Auditoria Médica , Pessoa de Meia-Idade , Alta do Paciente/estatística & dados numéricos , Readmissão do Paciente/economia , Readmissão do Paciente/estatística & dados numéricos , Assistência Perioperatória/economia , Assistência Perioperatória/métodos , Guias de Prática Clínica como Assunto , Avaliação de Programas e Projetos de Saúde
12.
Hong Kong Med J ; 23(6): 562-9, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29026056

RESUMO

INTRODUCTION: Lower urinary tract symptoms collectively represent a common condition among ageing men. There are, however, limited data on the frequency of individual symptoms in patients who seek specialist care. We conducted a multinational survey in South-East Asia to evaluate patients' self-reported prevalence, bother, treatment, and treatment satisfaction of four lower urinary tract symptoms namely, urgency, nocturia, slow stream, and post-micturition dribble. This report presents the analysis of the Hong Kong subpopulation. METHODS: This cross-sectional survey involved adult men aged over 18 years who attended a urology out-patient clinic because of lower urinary tract symptoms. A structured questionnaire, translated and validated in the local languages, was self-administered by patients. RESULTS: Of 1436 respondents surveyed in the region, 225 were from Hong Kong of whom most were aged 56 to 75 years, retired, and had no history of any previous prostate surgery. Overall, the self-reported prevalence of nocturia of at least one void per night was 93% (95% confidence interval, 90%-97%), slow stream 76% (71%-82%), post-micturition dribble 70% (64%-76%), and urgency 50% (43%-56%). Symptoms for which most respondents reported "some" or "a lot" of bother included: nocturia, defined as at least two voids per night (77%), and urgency and post-micturition dribble (73%). Only 39% to 54% of patients had previously received treatment but were not entirely satisfied with it. An understanding of their condition remained suboptimal. CONCLUSIONS: In Hong Kong, nocturia emerged as the most prevalent and one of the most bothersome symptoms among men who sought urologist care for lower urinary tract symptoms. Compared with the non-Hong Kong population, Hong Kong respondents tended to be highly symptomatic and bothered. They were, however, less likely to have received treatment and were generally less satisfied with previous treatment.


Assuntos
Sintomas do Trato Urinário Inferior/epidemiologia , Satisfação do Paciente , Idoso , Estudos Transversais , Hong Kong , Humanos , Masculino , Saúde do Homem , Pessoa de Meia-Idade , Noctúria/epidemiologia , Prevalência , Inquéritos e Questionários , Incontinência Urinária/epidemiologia
13.
Oncogenesis ; 6(7): e359, 2017 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-28692035

RESUMO

MUC1-C overexpression has been associated with the progression of pancreatic tumors by promoting the aggressive and metastatic phenotypes. As MUC1 is a STAT3 target gene, STAT3 plays a major role in regulating MUC1-C expression. In this study, we report an alternative mechanism by which integrin-linked kinase (ILK) post-transcriptionally modulates the expression of MUC1-C by maintaining its protein stability in pancreatic cancer cells. We found that ILK acts in concert with STAT3 to facilitate IL-6-mediated upregulation of MUC1-C; ILK depletion was equally effective as STAT3 depletion in abolishing IL-6-induced MUC1-C overexpression without disturbing the phosphorylation or cellular distribution of STAT3. Conversely, ectopic expression of constitutively active ILK increased MUC1-C expression, though this increase was not noted with kinase-dead ILK. This finding suggests the requirement of the kinase activity of ILK in regulating MUC1-C stability, which was confirmed by using the ILK kinase inhibitor T315. Furthermore, our data suggest the involvement of protein kinase C (PKC)δ in mediating the suppressive effect of ILK inhibition on MUC1-C repression. For example, co-immunoprecipitation analysis indicated that ILK depletion-mediated MUC1-C phosphorylation was accompanied by increased phosphorylation of PKCδ at the activation loop Thr-507 and increased binding of PKCδ to MUC1-C. Conversely, ILK overexpression resulted in decreased PKCδ phosphorylation. From a mechanistic perspective, the present finding, together with our recent report that ILK controls the expression of oncogenic KRAS through a regulatory loop, underscores the pivotal role of ILK in promoting pancreatic cancer progression.

14.
Oncogene ; 36(41): 5768-5769, 2017 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-28714962

RESUMO

This corrects the article DOI: 10.1038/onc.2014.445.

15.
Neoplasma ; 64(5): 681-692, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28592114

RESUMO

Oleanolic acid (OA) and its derivatives are a novel emerging class of compounds. Although OA exhibits potent anticancer and anti-inflammatory function, the potential effect of its new derivatives (SZC014) in human breast cancers has not been understood yet. In this investigation, we demonstrated the anticancer effect of SZC014, a novel OA derivative and identified the possible mechanisms by which SZC014 induced MCF-7 cell death. The biological functions of SZC014 were validated by MTT, migration and colony formation assays in breast cancer cells. Cell apoptosis was monitored by Annexin V- FITC assay. Intracellular ROS and cell cycle were measured by flow cytometric analysis. Western blot was used to detect protein expression level. Our present results fully demonstrated that SZC014 inhibits breast cancer cells proliferation, colony formation, and cell migration. Further investigation verified that ROS generation, apoptosis induction and G0/G1 phase arrest was observed in SZC014-treated MCF-7 cells. However, pretreatment with N-acetyl- L-cysteine (NAC), a ROS scavenger, increased the expression of procaspase-3. Additionally, SZC014 treatment suppressed the levels of Akt, phosphorylated-Akt (p-Akt), COX-2, p-p65 in the cytoplasmic and p65 in nuclear. Furthermore, the inhibition of p65 nuclear translocation was confirmed by immunofluorescence staining. These data show that SZC014 is an effectively selective anticancer agent against breast cancer cells, highlighting the potential use of this derivative as a breast cancer therapeutic agent.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/patologia , Ácido Oleanólico/análogos & derivados , Pirrolidinas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Humanos , Células MCF-7 , Ácido Oleanólico/farmacologia
16.
Nutr Diabetes ; 7(3): e246, 2017 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-28287631

RESUMO

BACKGROUND/OBJECTIVES: Acrylamide is present in mainstream cigarette smoke and in some food prepared at high temperature. Animal studies have shown that acrylamide exposure reduces body weight. Prenatal exposure to acrylamide also has been linked to reduced birth weight in human. Whether acrylamide exposure is associated with altered body compositions in adults is not clear. SUBJECTS/METHODS: We selected 3623 subjects (aged ⩾20 years) from a National Health and Nutrition Examination Survey (NHANES) in 2003-2004 to determine the relationship among hemoglobin adducts of acrylamide (HbAA), hemoglobin adducts of glycidamide (HbGA) and body composition (body measures, bioelectrical impedance analysis (BIA), dual energy x-ray absorptiometry (DXA)). Data were adjusted for potential confounding variables. RESULTS: The geometric means and 95% CI concentrations of HbAA and HbGA were 60.48 (59.32-61.65) pmol/g Hb and 55.64 (54.40-56.92) pmol/g Hb, respectively. After weighting for sampling strategy, we identified that one-unit increase in natural log-HbAA, but not HbGA, was associated with reduction in body measures (body weight, body mass index (BMI), subscapular/triceps skinfold), parameters of BIA (fat-free mass, fat mass, percent body fat, total body water) and parameters of DXA (android fat mass, android percent fat, gynoid fat/lean mass, gynoid percent mass, android to gynoid ratio). Subgroup analysis showed that these associations were more evident in subjects at younger age, male gender, whites, lower education level, active smokers and those with lower BMI. CONCLUSIONS: Higher concentrations of HbAA are associated with a decrease in body composition in the US general population. Further studies are warranted to clarify this association.


Assuntos
Acrilamida/toxicidade , Composição Corporal/efeitos dos fármacos , Hemoglobinas/análise , Absorciometria de Fóton , Adulto , Impedância Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Adulto Jovem
17.
J Test Eval ; 45(3)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28090126

RESUMO

Performance standard specifications for point chemical vapor detectors are established in ASTM E 2885-13 and ASTM E 2933-13. The performance evaluation of the detectors requires the accurate delivery of known concentrations of the chemical target to the system under test. Referee methods enable the analyte test concentration and associated uncertainties in the analyte test concentration to be validated by independent analysis, which is especially important for reactive analytes. This work extends the capability of a previously demonstrated method for using Fourier transform infrared (FT-IR) absorption spectroscopy for quantitatively evaluating the composition of vapor streams containing hazardous materials at Acute Exposure Guideline Levels (AEGL) to include test conditions colder than laboratory ambient temperatures. The described method covers the use of primary reference spectra to establish analyte concentrations, the generation of secondary reference spectra suitable for measuring analyte concentrations under specified testing environments, and the use of additional reference spectra and spectral profile strategies to mitigate the uncertainties due to impurities and water condensation within the low-temperature (7 °C, -5 °C) test cell. Important benefits of this approach include verification of the test analyte concentration with characterized uncertainties by in situ measurements co-located with the detector under test, near-real-time feedback, and broad applicability to toxic industrial chemicals.

18.
Oncogene ; 36(16): 2202-2214, 2017 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-27893715

RESUMO

The highly homeostasis-resistant nature of cancer cells leads to their escape from treatment and to liver metastasis, which in turn makes pancreatic ductal adenocarcinoma (PDAC) difficult to treat, especially the squamous/epithelial-to-mesenchymal transition (EMT)-like subtype. As the molecular mechanisms underlying tumour heterogeneity remain elusive, we investigated whether epigenetic regulation might explain inter-individual differences in the progression of specific subtypes. DNA methylation profiling performed on cancer tissues prior to chemo/radiotherapy identified one hypermethylated CpG site (CpG6882469) in the VAV1 gene body that was correlated with demethylation of two promoter CpGs (CpG6772370/CpG6772811) in both PDAC and peripheral blood. Transforming growth factor ß treatment induced gene-body hypermethylation, dissociation of DNMT1 from the promoter, and VAV1 expression via SMAD4 and mutant KrasG12D. Pharmacological inhibition of TGFß-VAV1 signalling decreased the squamous/EMT-like cancer cells, promoted nuclear VAV1 localization, and enhanced the efficacy of gemcitabine in prolonging the survival of KPfl/flC mice. Together, the three VAV1 CpGs serve as biomarkers for prognosis and early detection, and the TGFß-VAV1 axis represents a therapeutic target.


Assuntos
Adenocarcinoma/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas c-vav/genética , Fator de Crescimento Transformador beta/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Animais , Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Linhagem Celular Tumoral , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Progressão da Doença , Humanos , Camundongos , Camundongos Transgênicos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Regiões Promotoras Genéticas , Pirazóis/uso terapêutico , Proteína Smad4/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores
19.
Oncogene ; 35(37): 4891-902, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-26876205

RESUMO

The SET protein is a potent inhibitor of protein phosphatase 2A (PP2A). Here, we report the oncogenic role of SET in hepatocarcinogenesis, clinical aggressiveness and anti-hepatocellular carcinoma (HCC) therapeutics. By analyzing samples obtained from 147 HCC patients, we found that SET overexpression was detected specifically in 30.6% HCC tumor samples, and was significantly associated with worse clinical features and high p-Akt expression in HCC tumors. Co-expression of SET and Akt predicted shorter post-operative recurrence-free survival in this cohort (P=0.045). Furthermore, SET was significantly associated with cell growth and hepatosphere formation. To elucidate the anti-HCC potential of targeting SET, we generated a novel SET antagonist, EMQA (N(4)-(3-ethynylphenyl)-6,7-dimethoxy-N(2)-(4-phenoxyphenyl) quinazoline-2,4-diamine). EMQA enhanced PP2A activity via disrupting SET-PP2Ac (catalytic domain of PP2A) binding in HCC cells, which restored PP2A-mediated p-Akt downregulation and promoted HCC cell death. In HCC cells or recombinant proteins expressing the N- and C- truncated forms of SET, only the C-terminal SET was required for EMQA targeting. Furthermore, combining sorafenib and EMQA showed good synergism in inhibiting HCC survival. Our findings suggested the oncogenic role of SET and the adverse prognostic value of SET overexpression in HCC. This alteration defines a subgroup of HCC patients who could benefit from SET antagonists, such as EMQA.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Chaperonas de Histonas/genética , Neoplasias Hepáticas/tratamento farmacológico , Prognóstico , Quinazolinas/administração & dosagem , Fatores de Transcrição/genética , Animais , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proteínas de Ligação a DNA , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Chaperonas de Histonas/antagonistas & inibidores , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Quinazolinas/síntese química , Sorafenibe , Fatores de Transcrição/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Oncogene ; 35(30): 3897-908, 2016 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-26616862

RESUMO

Integrin-linked kinase (ILK) is a mediator of aggressive phenotype in pancreatic cancer. On the basis of our finding that knockdown of either KRAS or ILK has a reciprocal effect on the other's expression, we hypothesized the presence of an ILK-KRAS regulatory loop that enables pancreatic cancer cells to regulate KRAS expression. This study aimed to elucidate the mechanism by which this regulatory circuitry is regulated and to investigate the translational potential of targeting ILK to suppress oncogenic KRAS signaling in pancreatic cancer. Interplay between KRAS and ILK and the roles of E2F1, c-Myc and heterogeneous nuclear ribonucleoprotein as intermediary effectors in this feedback loop was interrogated by genetic manipulations through small interfering RNA/short hairpin RNA knockdown and ectopic expression, western blotting, PCR, promoter-luciferase reporter assays, chromatin immunoprecipitation and pull-down analyses. In vivo efficacy of ILK inhibition was evaluated in two murine xenograft models. Our data show that KRAS regulated the expression of ILK through E2F1-mediated transcriptional activation, which, in turn, controlled KRAS gene expression via hnRNPA1-mediated destabilization of the G-quadruplex on the KRAS promoter. Moreover, ILK inhibition blocked KRAS-driven epithelial-mesenchymal transition and growth factor-stimulated KRAS expression. The knockdown or pharmacological inhibition of ILK suppressed pancreatic tumor growth, in part, by suppressing KRAS signaling. These studies suggest that this KRAS-E2F1-ILK-hnRNPA1 regulatory loop enables pancreatic cancer cells to promote oncogenic KRAS signaling and to interact with the tumor microenvironment to promote aggressive phenotypes. This regulatory loop provides a mechanistic rationale for targeting ILK to suppress oncogenic KRAS signaling, which might foster new therapeutic strategies for pancreatic cancer.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/fisiologia , Neoplasias Pancreáticas/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/fisiologia , Transdução de Sinais/fisiologia , Animais , Linhagem Celular Tumoral , Fator de Transcrição E2F1/fisiologia , Transição Epitelial-Mesenquimal , Ribonucleoproteína Nuclear Heterogênea A1 , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-myc/fisiologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Ativação Transcricional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA