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2.
Anal Bioanal Chem ; 413(21): 5427-5438, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34279681

RESUMO

Neuroactive steroids are potent neuromodulators that play a critical role in both maternal and fetal health during pregnancy. These stress-responsive compounds are reportedly low in women with perinatal depression and may be associated with poor pregnancy outcomes in animal models. Chronic stress is a risk factor for adverse birth outcomes. Simultaneous quantification of neuroactive steroids, in combination with stress hormones cortisol/cortisone, provides an opportunity to investigate the synergistic relationship of these analytes within the convenience of one assay. A simple, reliable, and sensitive method for quantifying these endogenous compounds is necessary for further research with the potential to advance clinical diagnostic tools during pregnancy. Analytes were extracted from serum with a simple protein precipitation using methanol and then separated and quantified using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). After online extraction, analytes were separated using an Agilent Poroschell 120, 50 × 4.6 mm, 2.7 µm particle size, EC-C18 analytical column. The reliable quantification range was from 0.78 to 1000 ng/mL. QC sample inter- and intraday trueness was between 90 and 110% while inter- and intraday imprecision was less than 10%. Extracted samples were stable up to 7 days at 4 °C and extraction recovery was above 95%. Serum samples from 54 women in pregnancy were analyzed using this method. Here, we provide a validated, fast, and specific assay with sufficient sensitivity that allows for simultaneous quantification of blood serum concentrations of allopregnanolone (3α-hydroxy-5α-pregnan-20-one), pregnanolone (3α-hydroxy-5ß-pregnan-20-one), epipregnanolone (3ß-hydroxy-5ß-pregnan-20-one), pregnenolone, progesterone, cortisol, and cortisone in pregnancy for clinical study samples and clinical diagnostics.


Assuntos
Cortisona/sangue , Hidrocortisona/sangue , Pregnanolona/sangue , Progesterona/sangue , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Humanos , Isomerismo , Limite de Detecção , Gravidez , Espectrometria de Massas em Tandem/métodos
3.
J Transl Med ; 18(1): 280, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650803

RESUMO

BACKGROUND: Oropharyngeal squamous cell carcinoma (OPSCC) is often diagnosed at an advanced stage because the disease often causes minimal symptoms other than metastasis to neck lymph nodes. Better tools are required to assist with the early detection of OPSCC. MicroRNAs (miRNAs, miRs) are potential biomarkers for early head and neck squamous cell cancer diagnosis, prognosis, recurrence, and presence of metastatic disease. However, there is no widespread agreement on a panel of miRNAs with clinically meaningful utility for head and neck squamous cell cancers. This could be due to variations in the collection, storage, pre-processing, and isolation of RNA, but several reports have indicated that the selection and reproducibility of biomarkers has been widely affected by the methods used for data analysis. The primary analysis issues appear to be model overfitting and the incorrect application of statistical techniques. The purpose of this study was to develop a robust statistical approach to identify a miRNA signature that can distinguish controls and patients with inflammatory disease from patients with human papilloma virus positive (HPV +) OPSCC. METHODS: Small extracellular vesicles were harvested from the serum of 20 control patients, 20 patients with gastroesophageal reflux disease (GORD), and 40 patients with locally advanced HPV + OPSCC. MicroRNAs were purified, and expression profiled on OpenArray™. A novel cross validation method, using lasso regression, was developed to stabilise selection of miRNAs for inclusion in a prediction model. The method, named StaVarSel (for Stable Variable Selection), was used to derive a diagnostic biomarker signature. RESULTS: A standard cross validation approach was unable to produce a biomarker signature with good cross validated predictive capacity. In contrast, StaVarSel produced a regression model containing 11 miRNA ratios with potential clinical utility. Sample permutations indicated that the estimated cross validated prediction accuracy of the 11-miR-ratio model was not due to chance alone. CONCLUSIONS: We developed a novel method, StaVarSel, that was able to identify a panel of miRNAs, present in small extracellular vesicles derived from blood serum, that robustly cross validated as a biomarker for the detection of HPV + OPSCC. This approach could be used to derive diagnostic biomarkers of other head and neck cancers.


Assuntos
Carcinoma de Células Escamosas , Vesículas Extracelulares , Neoplasias de Cabeça e Pescoço , MicroRNAs , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/genética , Humanos , MicroRNAs/genética , Recidiva Local de Neoplasia , Neoplasias Orofaríngeas/diagnóstico , Neoplasias Orofaríngeas/genética , Papillomaviridae , Reprodutibilidade dos Testes , Soro , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
4.
Biomed Pharmacother ; 81: 218-224, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27261597

RESUMO

Sphingosine-1-phosphate (S1P) is a potent bioactive sphingolipid involved in the regulation of cell proliferation and cancer progression. Increased expression of S1P receptors has been detected in advanced breast tumours with poor prognosis suggesting that S1P receptors might control tumour response to chemotherapy. However, it remains unclear how the levels of S1P receptor expression are influenced by chemotherapy agents. Western immunoblotting, PCR analysis and fluorescent microscopy techniques were used in this study to analyze expression patterns of S1P receptors 2 and 3 (S1P2/S1P3) in MCF-7 breast adenocarcinoma cells treated by Tamoxifen (TAM) and/or Medroxyprogesterone acetate (MPA). We found that TAM/MPA induce downregulation of S1P3 receptors, but stimulate expression of S1P2. According to cell viability and caspase activity analyses, as expected, TAM activated apoptosis. We also detected TAM/MPA-induced autophagy marked by formation of macroautophagosomes and increased level of Beclin 1. Combined application of TAM and MPA resulted in synergistic apoptosis- and autophagy-stimulating effects. Assessed by fluorescent microscopy with autophagosome marker LAMP-2, changes in S1P receptor expression coincided with activation of autophagy, suggestively, directing breast cancer cells towards death. Further studies are warranted to explore the utility of manipulation of S1P2 and S1P3 receptor expression as a novel treatment approach.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptores de Lisoesfingolipídeo/metabolismo , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Medroxiprogesterona/farmacologia , Microscopia de Fluorescência , Tamoxifeno/farmacologia
5.
Br J Surg ; 98(11): 1589-98, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22059235

RESUMO

BACKGROUND: This study examined the interaction between natural history, current practice patterns in diagnosis, monitoring and treatment of oesophageal cancer, and associated health resource utilization and costs. METHODS: A cost analysis of a prospective population-based cohort of 1100 patients with a primary diagnosis of oesophageal cancer was performed using chart review from the Australian Cancer Study Clinical Follow-Up Study. The analysis enabled estimation of healthcare resources and associated costs in 2009 euros by stage of disease and treatment pathway. RESULTS: Most patients (88·5 per cent) presented with stage II, III or IV cancer; 61·1 per cent (672 of 1100) were treated surgically. Overall mean costs were €37,195 (median €29,114) for patients undergoing surgery and €17,281 (median €13,066) for those treated without surgery. Surgery contributed 66·4 per cent of the total costs (mean €24,697 per patient) in the surgical group. In the non-surgical group, use of chemotherapy was more prevalent (81·9 per cent of patients) and contributed 61·1 per cent of the total costs. Other important cost determinants were gastro-oesophageal junction tumours, treatment location and tumour stage. Mean costs of those monitored for Barrett's oesophagus (7·3 per cent of patients) were lower, although about one-third still presented with advanced-stage cancer. CONCLUSION: Overall costs for managing oesophageal cancer were high and dominated by surgery costs in patients treated surgically and by chemotherapy costs in patients treated without surgery. Radiotherapy, treatment location and cancer subtype were also important. Monitoring for Barrett's oesophagus and earlier-stage detection were associated with lower management costs, but the potential net benefit from surveillance strategies needs further investigation.


Assuntos
Adenocarcinoma/economia , Carcinoma de Células Escamosas/economia , Neoplasias Esofágicas/economia , Junção Esofagogástrica , Recursos em Saúde/estatística & dados numéricos , Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Adolescente , Adulto , Idoso , Austrália , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/economia , Esôfago de Barrett/terapia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/terapia , Análise Custo-Benefício , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/terapia , Feminino , Custos de Cuidados de Saúde , Recursos em Saúde/economia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Cuidados Pós-Operatórios/economia , Estudos Prospectivos , Adulto Jovem
6.
Clin Otolaryngol ; 34(2): 120-6, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19413609

RESUMO

OBJECTIVES: To compare pepsin, carbonic anhydrase III (CAIII), cyclooxygenase-2 (COX-2) and mucin 5AC (MUC5AC) expression in children with adenoid hypertrophy and normal controls. DESIGN: A non-randomised, controlled prospective study. SETTING: Two paediatric hospitals in Adelaide, South Australia. PARTICIPANTS: Children aged 2-10 years, 21 undergoing adenoidectomy and 12 controls undergoing routine dental surgery. MAIN OUTCOME MEASURES: We measured expression of pepsin, CAIII, COX-2 and MUC5AC levels by real-time RT-PCR, immunohistochemistry, and Western blot to determine any difference between children with hyperplastic adenoids and controls. RESULTS: Pepsin was not detected in any study or control adenoid by immunohistochemistry or Western blot. Real-time RT-PCR analysis showed a statistically significant difference between groups with respect to COX-2 (P = 0.027) and MUC5AC (P = 0.02) but no difference in CAIII expression (P = 0.414). A significant correlation was also found between COX-2 and MUC5AC expression (Kendall Tau = 0.4, P = 0.005). CONCLUSION: Our results suggest that the biochemical changes seen in adenoid hypertrophy are different to those seen in reflux-affected tissues. The decreased COX-2 and MUC5AC expression may be due to squamous metaplasia and other inflammatory changes associated with adenoid hypertrophy. Our findings infer there is little evidence of reflux being a major contributory factor in the pathophysiology of adenoidal hypertrophy.


Assuntos
Tonsila Faríngea/patologia , Refluxo Gastroesofágico/complicações , Adenoidectomia , Biópsia , Anidrase Carbônica III/genética , Criança , Pré-Escolar , Ciclo-Oxigenase 2/genética , Feminino , Refluxo Gastroesofágico/genética , Refluxo Gastroesofágico/patologia , Expressão Gênica/genética , Humanos , Hiperplasia/genética , Hiperplasia/patologia , Masculino , Mucina-5AC/genética , Pepsina A/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco , Estatística como Assunto
7.
FASEB J ; 15(2): 403-15, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11156956

RESUMO

The vitamin E analog alpha-tocopheryl succinate (alpha-TOS) can induce apoptosis. We show that the proapoptotic activity of alpha-TOS in hematopoietic and cancer cell lines involves inhibition of protein kinase C (PKC), since phorbol myristyl acetate prevented alpha-TOS-triggered apoptosis. More selective effectors indicated that alpha-TOS reduced PKCalpha isotype activity by increasing protein phosphatase 2A (PP2A) activity. The role of PKCalpha inhibition in alpha-TOS-induced apoptosis was confirmed using antisense oligonucleotides or PKCalpha overexpression. Gain- or loss-of-function bcl-2 mutants implied modulation of bcl-2 activity by PKC/PP2A as a mitochondrial target of alpha-TOS-induced proapoptotic signals. Structural analogs revealed that alpha-tocopheryl and succinyl moieties are both required for maximizing these effects. In mice with colon cancer xenografts, alpha-TOS suppressed tumor growth by 80%. This epitomizes cancer cell killing by a pharmacologically relevant compound without known side effects.


Assuntos
Apoptose/efeitos dos fármacos , Neoplasias do Colo/patologia , Neoplasias Colorretais/patologia , Vitamina E/análogos & derivados , Vitamina E/toxicidade , Animais , Anticorpos Monoclonais/farmacologia , Caspase 3 , Caspases/metabolismo , Neoplasias do Colo/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Genes bcl-2 , Humanos , Isoenzimas/antagonistas & inibidores , Células Jurkat , Cinética , Camundongos , Camundongos Nus , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Fosfoproteínas Fosfatases/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C-alfa , Proteína Fosfatase 2 , Acetato de Tetradecanoilforbol/farmacologia , Tocoferóis , Transplante Heterólogo , Células Tumorais Cultivadas , Vitamina E/uso terapêutico , Receptor fas/imunologia , Receptor fas/fisiologia
8.
J Biol Chem ; 273(37): 24115-21, 1998 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-9727032

RESUMO

Protein kinase C (PKC) activators, such as the tumor-promoting phorbol esters, have been reported to protect several cell lines from apoptosis induced by a variety of agents. Recent evidence suggests that PKCepsilon is involved in protection of cardiac myocytes from hypoxia-induced cell death (Gray, M. O., Karliner, J. S., and Mochly-Rosen, D. (1997) J. Biol. Chem. 272, 30945-30951). We investigated the protective effects of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) on U937 histiocytic lymphoma cells induced to undergo apoptosis by tumor necrosis factor-alpha (TNF-alpha) or by the specific PKC inhibitor calphostin C. U937 cells were transiently permeabilized with a peptide (epsilonV1-2) derived from the V1 region of PKCepsilon that has been reported to specifically block translocation of PKCepsilon. The epsilonV1-2 peptide blocked the inhibitory effect of TPA on both TNF-alpha- and calphostin C-induced apoptosis. A scrambled version of epsilonV1-2 and a peptide reported to inhibit PKCbeta translocation (betaC2-4) had no effect on the ability of TPA to inhibit apoptosis. These results suggest that PKCepsilon is required for the protective effect of TPA in TNF-alpha- and calphostin C-induced apoptosis. Furthermore, calphostin C reduced membrane-associated PKCepsilon activity and immunoreactivity, suggesting that PKCepsilon may play an important role in leukemic cell survival.


Assuntos
Apoptose/fisiologia , Isoenzimas/metabolismo , Naftalenos/farmacologia , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Apoptose/efeitos dos fármacos , Cromatina/efeitos dos fármacos , Cromatina/fisiologia , Fragmentação do DNA , Inibidores Enzimáticos/farmacologia , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Cinética , Linfoma Difuso de Grandes Células B , Nucleossomos/efeitos dos fármacos , Nucleossomos/fisiologia , Fragmentos de Peptídeos/farmacologia , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/química , Proteína Quinase C-épsilon , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/fisiologia
9.
FEBS Lett ; 401(2-3): 148-52, 1997 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-9013876

RESUMO

The novel lipid second messenger, ceramide, induced apoptosis in PC12 cells as determined morphologically by nuclear appearance and internucleosomal DNA fragmentation. Apoptosis was induced by exogenous C2-ceramide in a dose- and time-dependent manner. Natural ceramide and C6-ceramide had a similar effect. This response was specific since the structural analog C2-dihydroceramide and other related lipids failed to initiate apoptosis. The apoptotic effect of ceramide also depends critically on cell plating density. Furthermore, the peptide inhibitor of interleukin-1beta converting enzyme (ICE)-like proteases, Z-VAD.FMK, completely prevented the nuclear changes induced by ceramide, implicating the involvement of ICE-like protease activation in ceramide-induced apoptosis in PC12 cells.


Assuntos
Apoptose/efeitos dos fármacos , Ceramidas/farmacologia , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Caspase 1 , Contagem de Células , Cisteína Endopeptidases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Cinética , Células PC12 , Ratos
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