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Prostate cancer is initially regulated by the androgen receptor (AR), a ligand-activated, transcription factor, and is in a hormone-dependent state (hormone-sensitive prostate cancer (HSPC)), but eventually becomes androgen-refractory (castration-resistant prostate cancer (CRPC)) because of mechanisms that bypass the AR, including by activation of ErbB3, a member of the epidermal growth factor receptor family. ErbB3 is synthesized in the cytoplasm and transported to the plasma membrane for ligand binding and dimerization, where it regulates downstream signaling, but nuclear forms are reported. Here, we demonstrate in prostatectomy samples that ErbB3 nuclear localization is observed in malignant, but not benign prostate, and that cytoplasmic (but not nuclear) ErbB3 correlated positively with AR expression but negatively with AR transcriptional activity. In support of the latter, androgen depletion upregulated cytoplasmic, but not nuclear ErbB3, while in vivo studies showed that castration suppressed ErbB3 nuclear localization in HSPC, but not CRPC tumors. In vitro treatment with the ErbB3 ligand heregulin-1ß (HRG) induced ErbB3 nuclear localization, which was androgen-regulated in HSPC but not in CRPC. In turn, HRG upregulated AR transcriptional activity in CRPC but not in HSPC cells. Positive correlation between ErbB3 and AR expression was demonstrated in AR-null PC-3 cells where stable transfection of AR restored HRG-induced ErbB3 nuclear transport, while AR knockdown in LNCaP reduced cytoplasmic ErbB3. Mutations of ErbB3's kinase domain did not affect its localization but was responsible for cell viability in CRPC cells. Taken together, we conclude that AR expression regulated ErbB3 expression, its transcriptional activity suppressed ErbB3 nuclear translocation, and HRG binding to ErbB3 promoted it.
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Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Receptores Androgênicos , Humanos , Masculino , Androgênios/metabolismo , Linhagem Celular Tumoral , Ligantes , Neuregulina-1/genética , Neoplasias da Próstata/metabolismo , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Proteína Tirosina Quinases , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismoRESUMO
BACKGROUND: Despite overexpression of the ErbB (EGFR/HER2/ErbB3/ErbB4) family in castration-resistant prostate cancer (CRPC), some inhibitors of this family, including the dual EGFR/HER2 inhibitor lapatinib, failed in Phase II clinical trials. Hence, we investigated mechanisms of lapatinib resistance to determine whether alternate ErbB inhibitors can succeed. METHODS: The CWR22 human tumour xenograft and its CRPC subline 22Rv1 and sera from lapatinib-treated CRPC patients from a previously reported Phase II trial were used to study lapatinib resistance. Mechanistic studies were conducted in LNCaP, C4-2 and 22Rv1 cell lines. RESULTS: Lapatinib increased intratumoral HER2 protein, which encouraged resistance to this treatment in mouse models. Sera from CRPC patients following lapatinib treatment demonstrated increased HER2 levels. Investigation of the mechanism of lapatinib-induced HER2 increase revealed that lapatinib promotes HER2 protein stability, leading to membrane localisation, EGFR/HER2 heterodimerisation and signalling, elevating cell viability. Knockdown of HER2 and ErbB3, but not EGFR, sensitised CRPC cells to lapatinib. At equimolar concentrations, the recently FDA-approved pan-ErbB inhibitor dacomitinib decreased HER2 protein stability, prevented ErbB membrane localisation (despite continued membrane integrity) and EGFR/HER2 heterodimerisation, thereby decreasing downstream signalling and increasing apoptosis. CONCLUSIONS: Targeting the EGFR axis using the irreversible pan-ErbB inhibitor dacomitinib is a viable therapeutic option for CRPC.
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Lapatinib/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Quinazolinonas/uso terapêutico , Receptor ErbB-2/biossíntese , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Receptores ErbB/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias de Próstata Resistentes à Castração/metabolismo , Multimerização Proteica , Receptor ErbB-2/sangue , Receptor ErbB-2/químicaRESUMO
AIM: Escalating rates of childhood mental health disorders constitute a serious issue for countries like Pakistan. However, due to a scarce number of studies on childhood behavioural problems, understanding the magnitude and gap of the problem is a challenge. Thus, the present study is intended to bridge this gap. This study provides estimates for prevalence, associated demographic risk factors and the impact of behavioural and emotional problems among school children. METHODS: A sample of children (n = 800) from public schools of Islamabad were selected using two-stage cluster random sampling. Data were collected from parents through telephonic interviews using the Strengths and Difficulties Questionnaire. RESULTS: Prevalence of overall behaviour problems accounted for 15.9%. For conduct problems, estimates were around 26.6%, for emotional problems 22.5%, for peer problems 13%, for hyperactivity 10.6% and for social problems 3% in the initial analysis. Mother's education also appeared to be a significant predictor for mental health problems of youth, where low maternal education was associated with high prevalence and higher impact of emotional and behavioural problems in the present sample. CONCLUSIONS: Prevalence estimates of the current study call for attention towards improving mental health services and access to children who are at risk or are having mental health problems. In the context of scarcity of the data from countries like Pakistan, the findings should be considered a call for mental health service providers, researchers and policymakers to scale up mental health services for youth in Pakistan.
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Sintomas Afetivos/epidemiologia , Transtornos do Comportamento Infantil/epidemiologia , Fatores de Risco , Adolescente , Criança , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Pais/psicologia , Prevalência , Instituições Acadêmicas , Inquéritos e QuestionáriosRESUMO
Bladder cancer is among the top ten most common cancers, with about ~380,000 new cases and ~150,000 deaths per year worldwide. Tumor relapse following chemotherapy treatment has long been a significant challenge towards completely curing cancer. We have utilized a patient-derived bladder cancer xenograft (PDX) platform to characterize molecular mechanisms that contribute to relapse following drug treatment in advanced bladder cancer. Transcriptomic profiling of bladder cancer xenograft tumors by RNA-sequencing analysis, before and after relapse, following a 21-day cisplatin/gemcitabine drug treatment regimen identified methionine adenosyltransferase 1a (MAT1A) as one of the significantly upregulated genes following drug treatment. Survey of patient tumor sections confirmed elevated levels of MAT1A in individuals who received chemotherapy. Overexpression of MAT1A in 5637 bladder cancer cells increased tolerance to gemcitabine and stalled cell proliferation rates, suggesting MAT1A upregulation as a potential mechanism by which bladder cancer cells persist in a quiescent state to evade chemotherapy.
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Antineoplásicos/farmacologia , Sobrevivência Celular/genética , Resistencia a Medicamentos Antineoplásicos/genética , Metionina Adenosiltransferase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metionina Adenosiltransferase/metabolismo , Camundongos , Transcriptoma , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/mortalidade , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
OBJECTIVE: To examine the factors associated with caregivers' burden in individuals providing care to family members suffering from serious mental illness. METHODS: This Cross Sectional Study was carried out at Armed Forces Institute of Mental Health, Rawalpindi, from May 2015 to December 2015. A purposive sample of 120 family caregivers (60 males and 60 females, age range= 18-65) who were taking care of patients with serious mental illness (i.e. Major Depressive Disorder, Bipolar Disorder & Schizophrenia) for at least one year were recruited from the hospital and assessed through Zarit Burden Interview (ZBI) and Brief COPE inventory. The decline in functional status, and diminished physical capacity compromising the independent living of the care recipient was assessed through Katz Index of Independence in Activities of daily living (ADL) and Lawton Instrumental activities of daily living (IADL). RESULTS: The results suggest that the longer the duration of illness (F=25.71, p < 0.01), with increased impairments of care-recipients, (decline in functional status, F=21.33, p < 0.001; diminished physical capacity F =32.41, p < 0.001) the more the burden experienced by the caregivers. Moreover, caregivers who were married (t=-2.98, p < .01), less educated (t =5.48, p < .01), lived in rural area (t = -7.99, p < .01), had lower monthly income (t = -4.95, p < .01) provide longer hours of caregiving (F=19.12, p < 0.001) and used avoidant coping behavior (F= 56.37, p < 0.001) reported significantly higher caregiver burden than caregivers who were unmarried, more educated, lived in urban area and had better income. CONCLUSION: The results of study demonstrate that caring for family members with serious mental illness impacts the caregivers' wellbeing. It, therefore, highlights the need for support and counseling services for the caregivers to reduce the burden of caring.
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BACKGROUND AND OBJECTIVE: Fertility control preferences and maternal healthcare have recently become a major concern for developing nations with evidence suggesting that low fertility control rates and poor maternal healthcare are among major obstructions in ensuring health and social status for women. Our objective was toanalyze the factors that influence women's autonomy, access to maternal healthcare, and fertility control preferences in Pakistan. METHODS: Data consisted of 11,761 ever-married women of ages 15-49 years from PDHS, 2012-13. Variables included socio-demographics, women's autonomy, fertility control preferences and access to maternal healthcare. RESULTS: Findings from multivariate analysis showed that women's younger age, having less than three number of children and independent or joint decision-making (indicators of high autonomy) remained the most significant predictors for access to better quality maternal healthcare and better fertility control preferences when other variables were controlled. CONCLUSION: Women's access to good quality maternal health care and fertility control preferences are directly and indirectly influenced by their demographic characteristics and decision-making patterns in domestic affairs.
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Intervention and prevention programs for children with externalizing problems frequently involve children with co-occurring internalizing problems. Little is known about how these co-occurring internalizing problems predict outcomes, particularly for programs involving cognitive-behavioral strategies. The current study examined how a set of child-related risk factors (including anxiety and depressive symptoms) predicted change in parent- and teacher-reported externalizing problems following a school-based preventative intervention for children at risk for externalizing problems. Participants included 112 preadolescent children (ages 9-12) who participated in a study designed to evaluate the efficacy of the Coping Power Program (Lochman & Wells, 2004 ). Participants included 81 boys (68%) who were primarily African American (69%) or Caucasian (30%). Regression analyses were conducted to examine predictors of change in parent- and teacher-reported externalizing problems on the Behavior Assessment System for Children (Reynolds & Kamphaus, 1992 ). Results indicated that greater child depression symptoms (as reported by parent or teacher) were associated with a larger reduction in externalizing behavior problems based on parent or teacher report. This effect was found in both the parent and teacher models and held after controlling for a number of child-oriented baseline variables including baseline aggression. Future research studies should examine whether co-occurring symptoms of depression relate to enhanced changes in externalizing problems following intervention for externalizing problems, particularly when cognitive-behavioral interventions are utilized. In addition, it will be important for studies to examine such effects relative to a control group and/or alternative treatment conditions and to further explore possible mechanisms of change.
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Adaptação Psicológica , Transtornos de Ansiedade/psicologia , Depressão/psicologia , Transtornos de Ansiedade/epidemiologia , Criança , Terapia Cognitivo-Comportamental , Comorbidade , Depressão/epidemiologia , Feminino , Humanos , Masculino , Fatores de Risco , Resultado do TratamentoRESUMO
The rise in mental health concerns of university students is causing a serious hinderance to their wellbeing, impeding their functioning. The socio-economic and political friction in low- and middle-income countries adds to their vulnerability and calls for a cost-effective indigenous intervention. Consequently, this study aimed to inform a large definitive trial by assessing the feasibility and acceptability of a randomized controlled trial (RCT) design evaluating a culturally adapted online Mindfulness Training Course (MTC) used to improve stress and wellbeing among Pakistani university students. A two-arm pilot randomized controlled trial was conducted. University students (n = 156) were randomly assigned to either the MTC group (n = 80) or Wait-list (WL) control group (n = 76) and completed baseline and post-intervention self-report measures for mindfulness, stress and psychological wellbeing. Additionally, semi-structured interviews were conducted with consenting MTC group participants (n = 18) to explore their views about MTC, employing reflexive thematic analysis. Of 80 participants randomized to the MTC group, 32 completed the course, whereas, from the 156 randomized participants, 102 completed assessment surveys. Feasibility and acceptability indicators showed high recruitment, compliance, and adherence to MTC, with practical steps for randomization and online data collection. Further results showed higher levels of mindfulness and psychological wellbeing and lowered stress levels in the MTC group compared to the control group. The attrition and dropout rates were high; however, the feedback from participants who completed the MTC was highly positive and encouraging. In conclusion, if the trial proceeds with increased outreach in a large-scale RCT, the recruitment might be revised to reduce attrition rates. Further recommendations are discussed.
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Atenção Plena , Humanos , Atenção Plena/métodos , Paquistão , Estudos de Viabilidade , Projetos Piloto , Universidades , Estudantes/psicologia , Estresse Psicológico/terapia , Estresse Psicológico/psicologiaRESUMO
Cisplatin-based combination chemotherapy is the foundation for treatment of advanced bladder cancer (BlCa), but many patients develop chemoresistance mediated by increased Akt and ERK phosphorylation. However, the mechanism by which cisplatin induces this increase has not been elucidated. Among six patient-derived xenograft (PDX) models of BlCa, we observed that the cisplatin-resistant BL0269 express high epidermal growth factor receptor, ErbB2/HER2 and ErbB3/HER3. Cisplatin treatment transiently increased phospho-ErbB3 (Y1328), phospho-ERK (T202/Y204) and phospho-Akt (S473), and analysis of radical cystectomy tissues from patients with BlCa showed correlation between ErbB3 and ERK phosphorylation, likely due to the activation of ERK via the ErbB3 pathway. In vitro analysis revealed a role for the ErbB3 ligand heregulin1-ß1 (HRG1/NRG1), which is higher in chemoresistant lines compared to cisplatin-sensitive cells. Additionally, cisplatin treatment, both in PDX and cell models, increased HRG1 levels. The monoclonal antibody seribantumab, that obstructs ErbB3 ligand-binding, suppressed HRG1-induced ErbB3, Akt and ERK phosphorylation. Seribantumab also prevented tumor growth in both the chemosensitive BL0440 and chemoresistant BL0269 models. Our data demonstrate that cisplatin-associated increases in Akt and ERK phosphorylation is mediated by an elevation in HRG1, suggesting that inhibition of ErbB3 phosphorylation may be a useful therapeutic strategy in BlCa with high phospho-ErbB3 and HRG1 levels.
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Cisplatino , Neoplasias da Bexiga Urinária , Humanos , Animais , Cisplatino/farmacologia , Anticorpos Monoclonais , Neuregulina-1 , Ligantes , Proteínas Proto-Oncogênicas c-akt , Neoplasias da Bexiga Urinária/tratamento farmacológico , Modelos Animais de DoençasRESUMO
BACKGROUND: The purpose of the study was to evaluate and compare the HRQOL of paediatric cancer in comparison to the healthy children across age groups, using PedsQLTM 4.0 Generic Core Scales and the PedsQL™ Cancer Module. METHOD: The PedsQLTM 4.0 Generic Core Scales and PedsQL Cancer Module 3.0 were administered on 56 children including 26 cancer patients and 30 healthy children while employing self and proxy report forms. Furthermore, the results were compared with their healthy comparison group. RESULTS: The results indicated a significant relationship between HRQOL reports of cancer patients and their parents. However, the mean of paediatric cancer patients is significantly lower as compare to their healthy comparison group. The mean of proxy report is lower overall on both PedsQL and PedsQL cancer module reports. CONCLUSION: Conclusively, overall HRQOL of cancer patients was lower than healthy children but it is quite similar to their parents' perception. Whereas, the parental mean on PedsQL and PedsQL 3.0 Cancer Module are significantly low. The study indicated a marked difference between cancer patients and healthy children's HRQOL perception and unfortunately in country like Pakistan where cancer is on increase, no significant work has yet been done to explore this area of research. The present study highlighted the need to focus on the particular psychological health services required to serve the physically challenged population.
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Neoplasias/psicologia , Pediatria , Psicometria/métodos , Qualidade de Vida , Inquéritos e Questionários/normas , Feminino , Indicadores Básicos de Saúde , Humanos , Masculino , Neoplasias/terapia , PaquistãoRESUMO
This study examined cultural specificity in how interpretations about peer provocation are associated with revenge goals and aggression. The sample consisted of young adolescents from the United States (369 seventh-graders; 54.7% male; 77.2% identified as White) and from Pakistan (358 seventh-graders; 39.2% male). Participants rated their interpretations and revenge goals in response to six peer provocation vignettes and completed peer nominations of aggressive behavior. Multi-group SEM models indicated cultural specificity in how interpretations were related to revenge goals. Interpretations that a friendship with the provocateur was unlikely were uniquely related to revenge goals for Pakistani adolescents. For U.S adolescents positive interpretations were negatively related to revenge but self-blame interpretations were positively related to vengeance goals. Revenge goals were related to aggression similarly across groups.
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As a result of the devastating health effects of the COVID-19 outbreak, the lockdown has been considered a safety measure in many countries. In Pakistan, the first case of COVID-19 was reported in February 2020. The purpose of this qualitative study was to investigate people's risk perception and protective behavior during the lockdown. Twenty-two (22) participants from eight big cities across Pakistan were interviewed. A six-step reflective thematic analysis was used for data analysis. The study focused on risk perception and protective behaviors. Our main analytical goal was to understand how risk perception shapes human behavior in the context of lockdown, pandemic-related information flow, and corresponding meaning-making. The study revealed that people influenced by information and advice campaigns form a perception of risk that has shaped their protective behavior. They used familiar means of coping with distress, including the search for strength through religious belief practices and following the precautions recommended by health professionals through the media.
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Particulate matter is associated with increased morbidity and mortality; its effects depend on particle size and chemical content. It is important to understand the composition and resultant toxicological profile of particulate organic compounds, the largest and most complex fraction of particulate matter. The objective of the study was to delineate the nuclear magnetic resonance (NMR) spectral fingerprint of the biologically relevant water-soluble organic carbon (WSOC) fraction of size fractionated urban aerosol. A combination of one and two-dimensional NMR spectroscopy methods was used. The size distribution of particle mass, water-soluble extract, non-exchangeable organic hydrogen functional types and specific biomarkers such as levoglucosan, methane sulfonate, ammonium and saccharides indicated the contribution of fresh and aged wood burning emissions, anthropogenic and biogenic secondary aerosol for fine particles and primary traffic exhausts and pollen for large particles. Humic-like macromolecules in the fine particle size range included branched carbon structures containing aromatic, olefinic, keto and nitrile groups and terminal carboxylic and hydroxyl groups such as terpenoid-like polycarboxylic acids and polyols. Our study show that 2D-NMR spectroscopy can be applied to study the chemical composition of size fractionated aerosols.
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Poluentes Atmosféricos , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , ÁguaRESUMO
BACKGROUND: Osteosarcoma is the most prevalent type of primary bone sarcoma and is the major cause of deaths associated with cancer in children and adolescents. Despite novel and innovative therapies, early diagnosis of the osteosarcoma is still critically needed. Our study aimed to analyse the CCN3 proteins as a diagnostic marker and correlate their expression level with the severity of primary osteosarcoma patients. METHODS: In this prospective case-control study, after ethical clearance and informed consent, a total of 35 cases with primary osteosarcoma and ten otherwise healthy controls were enroled according to our strict inclusion-exclusion criteria. Tissue samples were collected during biopsy procedures in suspected cases and in controls during bone grafting procedures. The CCN3 expression level was measured by the western blotting assay. The clinic-radiological examinations were done in cases and graded according to the AJCC classification. Comparisons of CCN3 expression were measured between cases and controls, followed by correlation of their expression level with severity/grade of osteosarcoma in cases. RESULTS: All the demographic parameters showed insignificant differences. The CCN3 protein expressions were significantly upregulated in tissue samples of osteosarcoma patients (cases) compared to controls. The mean difference (p<0.0001) in CCN3 protein expression between cases' and controls' bony tissues was significant but showed insignificant correlation with the different grades of osteosarcoma. CONCLUSIONS: The upregulated CCN3 protein expression in osteosarcoma tissue along with significant differential manifestation in accordance with different grades of osteosarcoma make CCN3 suitable for a potential diagnostic biomarker. However, the author recommends further extensive multi-centric collaborative studies to increase our study reliability and generalizability.
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Biomarcadores Tumorais/metabolismo , Neoplasias Ósseas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Proteína Sobre-Expressa em Nefroblastoma/metabolismo , Osteossarcoma/diagnóstico , Adolescente , Adulto , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Estudos de Casos e Controles , Criança , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Osteossarcoma/cirurgia , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Adulto JovemRESUMO
An acute respiratory illness caused by a novel coronavirus, namely, severe acute respiratory syndrome coronavirus 2, the virus that causes coronavirus disease 2019 (COVID-19), began spreading across China in late December 2019. The disease gained global attention as it spread worldwide. Since the COVID-19 pandemic began, many studies have focused on the impact of the disease on conditions such as diabetes, cardiovascular disease, pulmonary disorders, and renal malfunction. However, few studies have focused on musculoskeletal disorders related to COVID-19 infection. In this review, we update the current knowledge on the coronavirus with special reference to its effects during and after the pandemic on musculoskeletal aliments, which may inform clinical practice.
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To our knowledge, our group is the first to demonstrate that NRDP1 is located in the nucleus as well as the cytoplasm of CaP cells. Subcellular fractionation, immunohistochemistry, and immunofluorescence analysis combined with confocal microscopy were used to validate this finding. Subcellular fractionation followed by western blot analysis revealed a strong association between AR and NRDP1 localization when AR expression and/or cellular localization was manipulated via treatment with R1881, AR-specific siRNA, or enzalutamide. Transfection of LNCaP with various NRDP1 and AR constructs followed by immunoprecipitation confirmed binding of NRDP1 to AR is possible and determined that binding requires the hinge region of AR. Co-transfection with NRDP1 constructs and HA-ubiquitin followed by subcellular fractionation confirmed that nuclear NRDP1 retains its ubiquitin ligase activity. We also show that increased nuclear NRDP1 is associated with PSA recurrence in CaP patients (n = 162, odds ratio; 1.238, p = 0.007) and that higher levels of nuclear NRDP1 are found in castration resistant cell lines (CWR22Rv1 and PC3) compared to androgen sensitive cell lines (LNCaP and MDA-PCa-3B). The combined data indicate that NRDP1 plays a role in mediating CaP progression and supports further investigation of both the mechanism by which nuclear transport occurs and the identification of specific nuclear targets.
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We have identified two genes from the parasitic nematode Haemonchus contortus, Hco-unc-49B and Hco-unc-49C that encode two GABA-gated chloride channel subunits. Electrophysiological analysis revealed that this channel has properties similar to those of the UNC-49 channel from the free-living nematode Caenorhabditis elegans. For example, the Hco-UNC-49B subunit forms a functional homomeric channel that responds to GABA and is highly sensitive to picrotoxin. Hco-UNC-49C alone does not respond to GABA but can assemble with Hco-UNC-49B to form a heteromeric channel with a lower sensitivity to picrotoxin. However, we did find that the Hco-UNC-49B/C heteromeric channel is significantly more responsive to agonists compared to the Hco-UNC-49B homomeric channel, which is the opposite trend to what has been found previously for the C. elegans channel. To investigate the subunit requirements for high agonist sensitivity, we generated cross-assembled channels by co-expressing the H. contortus subunits with UNC-49 subunits from C. elegans (Cel-UNC-49). Co-expressing Cel-UNC-49B with Hco-UNC-49C produced a heteromeric channel with a reduced sensitivity to GABA compared to that of the Cel-UNC-49B homomeric channel. In contrast, co-expressing Hco-UNC-49B with Cel-UNC-49C produced a heteromeric channel that, like the Hco-UNC-49B/C heteromeric channel, exhibits an increased sensitivity to GABA. These results suggest that the Hco-UNC-49B subunit is the key determinant for the high agonist sensitivity of heteromeric channels.
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Canais de Cloreto/metabolismo , Haemonchus/metabolismo , Proteínas de Helminto/metabolismo , Canais Iônicos/fisiologia , Receptores de GABA/metabolismo , Ácido gama-Aminobutírico/farmacologia , Sequência de Aminoácidos , Animais , Canais de Cloreto/efeitos dos fármacos , Canais de Cloreto/genética , Clonagem Molecular , Eletrofisiologia , Agonistas GABAérgicos/farmacologia , Proteínas de Helminto/efeitos dos fármacos , Proteínas de Helminto/genética , Ativação do Canal Iônico/efeitos dos fármacos , Dados de Sequência Molecular , Muscimol/farmacologia , Oócitos/metabolismo , Técnicas de Patch-Clamp , Receptores de GABA/efeitos dos fármacos , Receptores de GABA/genética , Transmissão Sináptica/fisiologia , Xenopus laevisRESUMO
PURPOSE: We previously showed that nuclear localization of the actin-binding protein, filamin A (FlnA), corresponded to hormone-dependence in prostate cancer. Intact FlnA (280 kDa, cytoplasmic) cleaved to a 90 kDa fragment which translocated to the nucleus in hormone-naïve cells, whereas in hormone-refractory cells, FlnA was phosphorylated, preventing its cleavage and nuclear translocation. We have examined whether FlnA localization determines a propensity to metastasis in advanced androgen-independent prostate cancer. EXPERIMENTAL DESIGN: We examined, by immunohistochemistry, FlnA localization in paraffin-embedded human prostate tissue representing different stages of progression. Results were correlated with in vitro studies in a cell model of prostate cancer. RESULTS: Nuclear FlnA was significantly higher in benign prostate (0.6612 +/- 0.5888), prostatic intraepithelial neoplasia (PIN; 0.6024 +/- 0.4620), and clinically localized cancers (0.69134 +/- 0.5686) compared with metastatic prostate cancers (0.3719 +/- 0.4992, P = 0.0007). Cytoplasmic FlnA increased from benign prostate (0.0833 +/- 0.2677), PIN (0.1409 +/- 0.2293), localized cancers (0.3008 +/- 0.3762, P = 0.0150), to metastases (0.7632 +/- 0.4414, P < 0.00001). Logistic regression of metastatic versus nonmetastatic tissue yielded the area under the receiver operating curve as 0.67 for nuclear-FlnA, 0.79 for cytoplasmic-FlnA, and 0.82 for both, indicating that metastasis correlates with cytoplasmic to nuclear translocation. In vitro studies showed that cytoplasmic localization of FlnA induced cell invasion whereas nuclear translocation of the protein inhibited it. FlnA dephosphorylation with the protein kinase A inhibitor H-89 facilitated FlnA nuclear translocation, resulting in decreased invasiveness and AR transcriptional activity, and induced sensitivity to androgen withdrawal in hormone-refractory cells. CONCLUSIONS: The data presented in this study indicate that in prostate cancer, metastasis correlates with cytoplasmic localization of FlnA and may be prevented by cleavage and subsequent nuclear translocation of this protein.
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Núcleo Celular/metabolismo , Proteínas Contráteis/metabolismo , Citoplasma/metabolismo , Proteínas dos Microfilamentos/metabolismo , Neoplasias da Próstata/metabolismo , Antagonistas de Androgênios/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular , Resistencia a Medicamentos Antineoplásicos , Filaminas , Humanos , Imuno-Histoquímica , Masculino , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias da Próstata/patologia , Análise Serial de TecidosRESUMO
Prostate cancer (PCa) is characterized by a unique dependence on optimal androgen receptor (AR) activity where physiological androgen concentrations induce proliferation but castrate and supraphysiological levels suppress growth. This feature has been exploited in bipolar androgen therapy (BAT) for castrate resistant malignancies. Here, we investigated the role of the tumor suppressor protein p14ARF in maintaining optimal AR activity and the function of the AR itself in regulating p14ARF levels. We used a tumor tissue array of differing stages and grades to define the relationships between these components and identified a strong positive correlation between p14ARF and AR expression. Mechanistic studies utilizing CWR22 xenograft and cell culture models revealed that a decrease in AR reduced p14ARF expression and deregulated E2F factors, which are linked to p14ARF and AR regulation. Chromatin immunoprecipitation studies identified AR binding sites upstream of p14ARF. p14ARF depletion enhanced AR-dependent PSA and TMPRSS2 transcription, hence p14ARF constrains AR activity. However, p14ARF depletion ultimately results in apoptosis. In PCa cells, AR co-ops p14ARF as part of a feedback mechanism to ensure optimal AR activity for maximal prostate cancer cell survival and proliferation.
Assuntos
Apoptose , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Proteína Supressora de Tumor p14ARF/metabolismo , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Inibidor p16 de Quinase Dependente de Ciclina/genética , Fatores de Transcrição E2F/genética , Fatores de Transcrição E2F/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Calicreínas/genética , Calicreínas/metabolismo , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p14ARF/genéticaRESUMO
BACKGROUND: Currently, the clinico-radiological method was used to analyze the healing progression of fractures globally, but even they are also unable to presume the impaired healing early. Hence till date, no reliable methods are available to predict the impaired healing early, so that it could be interventionally managed as required within the time. METHODS: In this prospective observational study, a total of 121 adults fractured patients and 108 healthy controls were analyzed. Peripheral blood samples were taken from controls (at once) and fractured cases (at different follow-ups) to quantify the Osteocalcin and Osteopontin mRNA and protein expression using qRT-PCR and western blotting assay respectively. In parallel to that the clinico-radiological follow-up examinations also done at various specific follow-up intervals up to 24th post-fracture weeks. RESULTS: As per the clinico-radiological status at the 24th week, fracture patients were divided into normal healing (nâ¯=â¯102) and impaired healing (nâ¯=â¯19) groups. Mean RUST score between normal healing and the impaired healing group showed a significant statistical difference at each follow-up. In both groups, expressions of Osteocalcin (mRNA & protein) were gradually up-regulated from the baseline to end of follow-ups, whereas Osteopontin mRNA as well as protein gradually up-regulated from the baseline to a peak value at 10th day, then declined. In general, the Osteocalcin and Osteopontin mean fold expressions were higher in normal healing as compared to the impaired healing groups.A significant correlation was found between the mRNA expressions of Osteocalcin and Osteopontin with the RUST score at most of the follow-ups. However, the protein expressions were not shown any significant correlation. CONCLUSIONS: The Osteocalcin and Osteopontin expression will provide an early prediction of the healing outcomes of tibial fractures. This may open a new horizon for innovations to deal with complications associated with impaired fracture healing, especially in tibial bone fractures.