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1.
Breast Cancer Res ; 22(1): 122, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148314

RESUMO

BACKGROUND: The role of nuclear receptors in both the aetiology and treatment of breast cancer is exemplified by the use of the oestrogen receptor (ER) as a prognostic marker and treatment target. Treatments targeting the oestrogen signalling pathway are initially highly effective for most patients. However, for the breast cancers that fail to respond, or become resistant, to current endocrine treatments, the long-term outlook is poor. ER is a member of the nuclear receptor superfamily, comprising 48 members in the human, many of which are expressed in the breast and could be used as alternative targets in cases where current treatments are ineffective. METHODS: We used sparse canonical correlation analysis to interrogate potential novel nuclear receptor expression relationships in normal breast and breast cancer. These were further explored using whole transcriptome profiling in breast cancer cells after combinations of ligand treatments. RESULTS: Using this approach, we discovered a tumour suppressive relationship between the mineralocorticoid receptor (MR) and retinoic acid receptors (RAR), in particular RARß. Expression profiling of MR expressing breast cancer cells revealed that mineralocorticoid and retinoid co-treatment activated an expression program consistent with a reverse Warburg effect and growth inhibition, which was not observed with either ligand alone. Moreover, high expression of both MR and RARB was associated with improved breast cancer-specific survival. CONCLUSION: Our study reveals a previously unknown relationship between MR and RAR in the breast, which is dependent on menopausal state and altered in malignancy. This finding identifies potential new targets for the treatment of breast cancers that are refractory to existing therapeutic options.


Assuntos
Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Receptores de Mineralocorticoides/metabolismo , Receptores do Ácido Retinoico/metabolismo , Transdução de Sinais , Efeito Warburg em Oncologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Biologia Computacional , Feminino , Humanos , Receptores de Estrogênio/metabolismo , Receptores de Mineralocorticoides/genética , Taxa de Sobrevida , Células Tumorais Cultivadas
2.
Surg Endosc ; 34(4): 1776-1784, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31209609

RESUMO

INTRODUCTION: The Fellowship Council (FC) oversees 172 non-ACGME surgical fellowships offering 211 fellowship positions per year. These training programs cover multiple specialties including Advanced gastrointestinal (GI), Advanced GI/MIS, Bariatric, Hepatopancreaticobiliary (HPB), Flexible Endoscopy, Colorectal, and Thoracic Surgery. Although some data have been published detailing the practice environments (i.e., urban vs. rural) and yearly total case volumes of FC alumni, there is a lack of granular data regarding the practice patterns of FC graduates. The aim of this study was to gather detailed data on the specific case types performed and surgical approaches employed by recent FC alumni. METHODS: A 21-item survey covering 64 data points was emailed to 835 FC alumni who completed their fellowship between 2013 and 2017. Email addresses were obtained from FC program directors and FC archives. RESULTS: We received 327 responses (39% response rate). HPB, Advanced Colorectal, and Advanced Thoracic alumni appear to establish practices focused on their respective fields. Graduates from Advanced GI, Adv GI/MIS, and Bariatric programs appear to build practices with a mix of several complex GI case types including bariatrics, colorectal, foregut, HPB, and hernia cases. CONCLUSIONS: This is the first large data set to provide granular information on the practice patterns of FC alumni. FC trained surgeons perform impressive volumes of complex procedures, and minimally invasive approaches are extremely prevalent in these practices. Further, many graduates carve out practices with large footprints in robotics and endoscopy.


Assuntos
Competência Clínica/normas , Educação de Pós-Graduação em Medicina/métodos , Bolsas de Estudo/normas , Trato Gastrointestinal/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/educação , Feminino , Humanos , Masculino , Inquéritos e Questionários
3.
Artigo em Inglês | MEDLINE | ID: mdl-36011912

RESUMO

Welfare recipients were often considered the least deserving of COVID-related support. Despite the recent attention paid to the impact of COVID-19 pandemic on mental health, few studies have explored the mental distress experienced by welfare recipients. This cross-sectional study on female Comprehensive Social Security Allowance recipients in Hong Kong aimed to explore their level of mental distress and its association with a range of risk factors specific to welfare recipients. Hence, 316 valid cases from a local community center responded to our online survey. We found that 52.3%, 23.4%, and 78% of the participants showed moderate to extremely severe depression, anxiety, and stress symptoms, respectively. A higher level of mental distress was associated with having a psychiatric diagnosis, poorer social, and greater concerns over disciplining children, the living environment, daily expenses and being infected by COVID-19. Unexpectedly, being married, having a permanent residence, and having a job were not significant protective factors for this group. The models explained 45.5%, 44.6%, and 52.5% of the overall variance in the level of depression, anxiety, and stress (p < 0.01), respectively. Our findings have important implications for supporting female welfare recipients during a public health crisis and may help frontline staff and professionals provide prompt assistance to this group in need.


Assuntos
COVID-19 , Transtornos Mentais , Ansiedade/epidemiologia , Ansiedade/etiologia , COVID-19/epidemiologia , Criança , Estudos Transversais , Depressão/epidemiologia , Depressão/etiologia , Feminino , Hong Kong/epidemiologia , Humanos , Transtornos Mentais/epidemiologia , Pandemias , SARS-CoV-2 , Previdência Social
4.
PLoS Biol ; 6(11): e277, 2008 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-18998772

RESUMO

Previous studies in Saccharomyces cerevisiae have demonstrated that cryptic promoters within coding regions activate transcription in particular mutants. We have performed a comprehensive analysis of cryptic transcription in order to identify factors that normally repress cryptic promoters, to determine the amount of cryptic transcription genome-wide, and to study the potential for expression of genetic information by cryptic transcription. Our results show that a large number of factors that control chromatin structure and transcription are required to repress cryptic transcription from at least 1,000 locations across the S. cerevisiae genome. Two results suggest that some cryptic transcripts are translated. First, as expected, many cryptic transcripts contain an ATG and an open reading frame of at least 100 codons. Second, several cryptic transcripts are translated into proteins. Furthermore, a subset of cryptic transcripts tested is transiently induced in wild-type cells following a nutritional shift, suggesting a possible physiological role in response to a change in growth conditions. Taken together, our results demonstrate that, during normal growth, the global integrity of gene expression is maintained by a wide range of factors and suggest that, under altered genetic or physiological conditions, the expression of alternative genetic information may occur.


Assuntos
Cromatina/metabolismo , Regulação Fúngica da Expressão Gênica , Fases de Leitura Aberta/fisiologia , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Perfilação da Expressão Gênica , Genoma Fúngico , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Fases de Leitura Aberta/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/fisiologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/genética
5.
Ann Palliat Med ; 9(6): 4522-4533, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32008335

RESUMO

BACKGROUND: Palliative care aims to improve the quality of life for patients and their families, by helping them to cope with problems associated with illness. It targets four aspects of health: physical, psychological, social, and spiritual. Most of the current literature on palliative care is limited to the perspectives of health professionals. This study aims to investigate the views of outpatients receiving palliative care at the Hong Kong Queen Mary Hospital Hospice Centre (HKQMHHC), which offers palliative care services to cancer patients. METHODS: This observational cross-sectional study was performed with the completion of a single paper- based original questionnaire over 18 afternoon clinic sessions on Thursdays and Fridays from December 2017 to February 2018 at the HKQMHHC. The questionnaire was designed to examine patients' perspectives; in particular, the Edmonton Symptom Assessment Scale (ESAS) was used to assess their symptoms. Descriptive and univariate analyses were performed. RESULTS: One hundred patients attending HKQMHHC were included in the study. The study revealed that all the mean scores for aspects of care offered at the centre were above 8, on a scale of 0-10 with 0 being extremely inadequate and 10 being extremely adequate. Each respondent was able to identify an average of 1.82 of the 4 aspects of palliative care. Eighty-seven percent of respondents perceived the physical aspect of this care to be of the highest priority. A negative correlation (P<0.05) was found between the extent of symptoms experienced by the patient and their satisfaction towards the services offered. CONCLUSIONS: Patients generally held very positive attitudes, reflecting that the services sufficiently met their needs. However, owing to their rather limited knowledge, this may have restricted their perspectives to a largely superficial level, as many discerned palliative care to be simply targeting physical health with medical consultations. Considering the implications of the results, the addition of accessibility and education components to Hong Kong's current system of palliative care is crucial in the betterment of such services for patients. There should also be increased local coverage of palliative care services to facilitate convenience of access. With reference to the World Health Organisation (WHO) palliative care model, the inclusion of a continued spectrum of services, such as physical and mental health activities and psychosocial counselling, should be reinforced throughout the progression of disease so as to better help patients to cope with illness. The discovery of the relationship between extent of symptoms experienced and patients' satisfaction towards services provided is a new direction for further study.


Assuntos
Hospitais para Doentes Terminais , Cuidados Paliativos , Estudos Transversais , Hong Kong , Humanos , Pacientes Ambulatoriais , Percepção , Qualidade de Vida , Inquéritos e Questionários
6.
Mol Biol Cell ; 17(2): 607-22, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16280363

RESUMO

The spatial activation of phosphoinositide 3-kinase (PI3-kinase) signaling at the axon growth cone generates phosphatidylinositol 3,4,5 trisphosphate (PtdIns(3,4,5)P3), which localizes and facilitates Akt activation and stimulates GSK-3beta inactivation, promoting microtubule polymerization and axon elongation. However, the molecular mechanisms that govern the spatial down-regulation of PtdIns(3,4,5)P3 signaling at the growth cone remain undetermined. The inositol polyphosphate 5-phosphatases (5-phosphatase) hydrolyze the 5-position phosphate from phosphatidylinositol 4,5 bisphosphate (PtdIns(4,5)P2) and/or PtdIns(3,4,5)P3. We demonstrate here that PIPP, an uncharacterized 5-phosphatase, hydrolyzes PtdIns(3,4,5)P3 forming PtdIns(3,4)P2, decreasing Ser473-Akt phosphorylation. PIPP is expressed in PC12 cells, localizing to the plasma membrane of undifferentiated cells and the neurite shaft and growth cone of NGF-differentiated neurites. Overexpression of wild-type, but not catalytically inactive PIPP, in PC12 cells inhibited neurite elongation. Targeted depletion of PIPP using RNA interference (RNAi) resulted in enhanced neurite differentiation, associated with neurite hyperelongation. Inhibition of PI3-kinase activity prevented neurite hyperelongation in PIPP-deficient cells. PIPP targeted-depletion resulted in increased phospho-Ser473-Akt and phospho-Ser9-GSK-3beta, specifically at the neurite growth cone, and accumulation of PtdIns(3,4,5)P3 at this site, associated with enhanced microtubule polymerization in the neurite shaft. PIPP therefore inhibits PI3-kinase-dependent neurite elongation in PC12 cells, via regulation of the spatial distribution of phospho-Ser473-Akt and phospho-Ser9-GSK-3beta signaling.


Assuntos
Neuritos/enzimologia , Fosfatidilinositol 3-Quinases/metabolismo , Monoéster Fosfórico Hidrolases/fisiologia , Animais , Células COS , Diferenciação Celular , Crescimento Celular , Chlorocebus aethiops , Cones de Crescimento/fisiologia , Hidrólise , Inositol Polifosfato 5-Fosfatases , Camundongos , Fator de Crescimento Neural/metabolismo , Neuritos/fisiologia , Neuritos/ultraestrutura , Células PC12 , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , Ratos
7.
Asia Pac Psychiatry ; 11(2): e12339, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30362264

RESUMO

INTRODUCTION: The purpose of this study was to examine the relationship between resilience and suicidal ideation, with coping strategies regarded as a mediator. METHODS: A total of 422 Hong Kong undergraduate students were recruited with convenience sampling. RESULTS: Simple linear regression was used to verify the negative relationship between resilience and suicidal ideation (P < 0.001). The results revealed that two out of four tested mediation models were accepted, with the coping strategies of approach and reappraisal acting as mediators (P < 0.001); the other two models were rejected when the coping strategies of emotional regulation and avoidance were the mediators. Regression analysis was performed to explore the effectiveness in reducing suicidal ideation in terms of the reappraisal coping strategy and the approach coping strategy, and the results indicated that the reappraisal coping strategy had greater effects than the approach coping strategy. DISCUSSION: Overall, the results of this study confirmed previous findings in the literature that resilience can alleviate the degree of suicidal ideation. Additionally, these results suggest further implications that adopting the approach and reappraisal coping strategies might make significant contributions to reducing the number of suicidal cases in society.


Assuntos
Adaptação Psicológica/fisiologia , Resiliência Psicológica , Estudantes/psicologia , Ideação Suicida , Adolescente , Adulto , Emoções/fisiologia , Feminino , Hong Kong , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Fatores de Risco , Inquéritos e Questionários , Adulto Jovem
8.
Sci Rep ; 6: 27531, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-27277538

RESUMO

The malaria parasite Plasmodium falciparum relies on efficient protein translation. An essential component of translation is the tryptophanyl-tRNA synthetase (TrpRS) that charges tRNA(trp). Here we characterise two isoforms of TrpRS in Plasmodium; one eukaryotic type localises to the cytosol and a bacterial type localises to the remnant plastid (apicoplast). We show that the apicoplast TrpRS aminoacylates bacterial tRNA(trp) while the cytosolic TrpRS charges eukaryotic tRNA(trp). An inhibitor of bacterial TrpRSs, indolmycin, specifically inhibits aminoacylation by the apicoplast TrpRS in vitro, and inhibits ex vivo Plasmodium parasite growth, killing parasites with a delayed death effect characteristic of apicoplast inhibitors. Indolmycin treatment ablates apicoplast inheritance and is rescuable by addition of the apicoplast metabolite isopentenyl pyrophosphate (IPP). These data establish that inhibition of an apicoplast housekeeping enzyme leads to loss of the apicoplast and this is sufficient for delayed death. Apicoplast TrpRS is essential for protein translation and is a promising, specific antimalarial target.


Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Triptofano-tRNA Ligase/antagonistas & inibidores , Apicoplastos/efeitos dos fármacos , Apicoplastos/enzimologia , Biologia Computacional , Citosol/metabolismo , Evolução Molecular , Teste de Complementação Genética , Proteínas de Fluorescência Verde/metabolismo , Indóis/química , Concentração Inibidora 50 , Filogenia , Plasmídeos/metabolismo , Plasmodium falciparum/enzimologia , Biossíntese de Proteínas , Triptofano/química
9.
J Steroid Biochem Mol Biol ; 145: 179-86, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24846828

RESUMO

Aromatase is the critical enzyme that converts androgens to estrogens. It is frequently highly expressed in the tumour bearing breast of women diagnosed with estrogen receptor positive tumours, resulting in dramatically increased local estrogen production to drive tumour progression. Expression of aromatase is regulated primarily at the transcriptional level of its encoding gene CYP19A1, located on chromosome 15 of the human genome. A characteristic feature of CYP19A1 expression is its use of alternative promoters to regulate transcription in a tissue-specific manner. In breast cancer, the increase in aromatase expression is mediated via higher expression of the distal adipose-specific promoter I.4 and a switch to the preferential use of proximal promoters I.3 and II. This results in a net increase of CYP19A1 transcripts in tumour-bearing breast up to 3-4-fold higher than normal breast. Current aromatase inhibitors - whilst efficacious - exhibit significant side effects that reduce patient compliance. Understanding the transcription factors and signalling pathways that control aromatase expression will lead to opportunities to develop breast-specific inhibitors with an improved side-effects profile. This article is part of a Special Issue entitled 'Essential role of DHEA'.


Assuntos
Aromatase/metabolismo , Mama/metabolismo , Estrogênios/biossíntese , Regulação Neoplásica da Expressão Gênica , Regulação da Expressão Gênica , Receptores de Estrogênio/metabolismo , Transcrição Gênica , Animais , Aromatase/genética , Neoplasias da Mama/metabolismo , Feminino , Humanos , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Animais , Camundongos , Camundongos Knockout , Regiões Promotoras Genéticas
10.
Mol Cell Endocrinol ; 394(1-2): 21-8, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25004254

RESUMO

The cytokine Tumor Necrosis Factor-α is critical to Estrogen Receptor positive breast cancer pathology, stimulating estrogen-biosynthesis pathways and preventing the differentiation of estrogen-producing fibroblasts. High concentrations of TNFα are detected in the tumor microenvironment, and infiltrating immune cells are thought to be a major source. This study identifies that TNFα is also a tumor-derived factor, expressed in ER+ tumour epithelial cells and regulated by 17-ß-estradiol (E2). Treatment of MCF-7, T47D and ZR-75 breast cancer cells with E2 increased TNFα mRNA and protein expression and secretion. This effect was mitigated with the use of ERα inhibitors 4-hydroy-tamoxifen and ICI-182780, indicating that E2-mediated TNFα induction was via the actions of ERα. Chromatin immunoprecipitation reveals ERα binding to the TNFα promoter upon stimulation with E2. This study demonstrates for the first time a positive feedback loop between estradiol and TNFα, critical in maintaining high levels of the hormone within the ER+ breast tumour microenvironment.


Assuntos
Células Epiteliais/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/genética , Regulação Neoplásica da Expressão Gênica , RNA Mensageiro/genética , Fator de Necrose Tumoral alfa/genética , Linhagem Celular Tumoral , Imunoprecipitação da Cromatina , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Estradiol/análogos & derivados , Estradiol/metabolismo , Antagonistas de Estrogênios/farmacologia , Receptor alfa de Estrogênio/antagonistas & inibidores , Receptor alfa de Estrogênio/metabolismo , Retroalimentação Fisiológica , Feminino , Fulvestranto , Humanos , Glândulas Mamárias Humanas/efeitos dos fármacos , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Regiões Promotoras Genéticas , Ligação Proteica , RNA Mensageiro/metabolismo , Transdução de Sinais , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Fator de Necrose Tumoral alfa/agonistas , Fator de Necrose Tumoral alfa/metabolismo
11.
PLoS One ; 8(6): e66343, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23822995

RESUMO

Parathyroid hormone-related protein (PTHrP) is a key component in breast development and breast tumour biology. PTHrP has been discovered as a causative agent of hypercalcaemia of malignancy and is also one of the main factors implicated in breast cancer mediated osteolysis. Clinical studies have determined that PTHrP expression by primary breast cancers was an independent predictor of improved prognosis. Furthermore, PTHrP has been demonstrated to cause tumour cell death both in vitro and in vivo. Apo2L/TRAIL is a promising new anti-cancer agent, due to its ability to selectively induce apoptosis in cancer cells whilst sparing most normal cells. However, some cancer cells are resistant to Apo2L/TRAIL-induced apoptosis thus limiting its therapeutic efficacy. The effects of PTHrP on cell death signalling pathways initiated by Apo2L/TRAIL were investigated in breast cancer cells. Expression of PTHrP in Apo2L/TRAIL resistant cell line MCF-7 sensitised these cells to Apo2L/TRAIL-induced apoptosis. The actions of PTHrP resulted from intracellular effects, since exogenous treatment of PTHrP had no effect on Apo2L/TRAIL-induced apoptosis. Apo2L/TRAIL-induced apoptosis in PTHrP expressing cells occurred through the activation of caspase-10 resulting in caspase-9 activation and induction of apoptosis through the effector caspases, caspase-6 and -7. PTHrP increased cell surface expression of Apo2L/TRAIL death receptors, TRAIL-R1 and TRAIL-R2. Antagonistic antibodies against the death receptors demonstrated that Apo2L/TRAIL mediated its apoptotic signals through activation of the TRAIL-R2 in PTHrP expressing breast cancer cells. These studies reveal a novel role for PTHrP with Apo2L/TRAIL that maybe important for future diagnosis and treatment of breast cancer.


Assuntos
Desaminases APOBEC/metabolismo , Neoplasias da Mama/patologia , Proteínas Musculares/metabolismo , Proteína Relacionada ao Hormônio Paratireóideo/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Humanos
12.
Mol Cell Biol ; 28(4): 1393-403, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18086892

RESUMO

We investigated the timing of the recruitment of Spn1 and its partner, Spt6, to the CYC1 gene. Like TATA binding protein and RNA polymerase II (RNAPII), Spn1 is constitutively recruited to the CYC1 promoter, although levels of transcription from this gene, which is regulated postrecruitment of RNAPII, are low. In contrast, Spt6 appears only after growth in conditions in which the gene is highly transcribed. Spn1 recruitment is via interaction with RNAPII, since an spn1 mutant defective for interaction with RNAPII is not targeted to the promoter, and Spn1 is necessary for Spt6 recruitment. Through a targeted genetic screen, strong and specific antagonizing interactions between SPN1 and genes encoding Swi/Snf subunits were identified. Like Spt6, Swi/Snf appears at CYC1 only after activation of the gene. However, Spt6 significantly precedes Swi/Snf occupancy at the promoter. In the absence of Spn1 recruitment, Swi/Snf is constitutively found at the promoter. These observations support a model whereby Spn1 negatively regulates RNAPII transcriptional activity by inhibiting recruitment of Swi/Snf to the CYC1 promoter, and this inhibition is abrogated by the Spn1-Spt6 interaction. These findings link Spn1 functions to the transition from an inactive to an actively transcribing RNAPII complex at a postrecruitment-regulated promoter.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Proteínas Nucleares/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Ativação Transcricional , Citocromos c/genética , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Chaperonas de Histonas , Proteínas Mutantes/metabolismo , Fenótipo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Subunidades Proteicas/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo , Transcrição Gênica , Fatores de Elongação da Transcrição
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