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1.
S Afr Med J ; 111(7): 627-634, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34382545

RESUMO

BACKGROUND: Thoughts of self-harm (TSH) are an important marker of mental health risk, and risk for attempted and completed suicide. While there is increasing attention being paid to mental health problems in pregnancy in South Africa (SA), TSH have received less attention despite some cross-sectional studies suggesting that prevalence may be high (12 - 39%). There is a dearth of longitudinal research to inform prevention and treatment. OBJECTIVES: To examine the rates of TSH across pregnancy in a longitudinal SA cohort and to investigate factors associated with the onset and persistence of TSH, as well as the relationship between TSH, depression and/or anxiety. METHODS: Women were enrolled in a prospective pregnancy cohort (S1000) in Soweto, SA between 2014 and 2016, and assessed using validated screening measures (Edinburgh Postnatal Depression Scale (EPDS) and State Trait Anxiety Index short form) in early and later pregnancy. Data were available for 649 women. TSH were determined using EPDS item 10. Logistic regression and bifactor models were used to determine factors associated with TSH across pregnancy. RESULTS:  Of the 649 women, 18% reported TSH at some stage during their pregnancy. Prevalence of TSH was slightly higher in early pregnancy (12.5%) than later in pregnancy (11.6%). TSH were associated with a history of mental illness (adjusted odds ratio (aOR) 4.17; 95% confidence interval (CI) 1.3 - 13.7; p=0.020), concurrent depression (aOR 4.8; 95%CI 2.7 - 8.6; p<0.001); marital stress (aOR 1.74; 95% CI 1.0 - 3.0; p=0.040); and practical support (aOR 0.43; 95% CI 0.2 - 1.0; p=0.040) using a multivariate logistic regression. Bifactor analysis examining depression and anxiety scales showed that TSH contributed the highest variance to a shared depression and anxiety factor in early pregnancy. Logistic regressions showed that early depression was a strong predictor of later reports of TSH. CONCLUSIONS:  The present study shows that the risk of TSH during pregnancy is relatively common, and starts early during pregnancy. Screening approaches could be simplified to encourage healthcare practitioners working in busy and over-burdened public healthcare settings to engage in identifying at-risk women. Efforts in improving early identification of mental health risk in pregnancy should be matched with strengthening of current treatment and referral options. Since practical support and a good marital relationship reduce the risk of TSH, these may be important avenues of focus for designing interventions.


Assuntos
Programas de Rastreamento/métodos , Complicações na Gravidez/psicologia , Ideação Suicida , Adulto , Ansiedade/complicações , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Depressão/complicações , Depressão/diagnóstico , Depressão/epidemiologia , Feminino , Humanos , Modelos Logísticos , Estudos Longitudinais , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia , Trimestres da Gravidez/psicologia , Prevalência , Escalas de Graduação Psiquiátrica , Fatores de Risco , Comportamento Autodestrutivo/complicações , Comportamento Autodestrutivo/epidemiologia , Comportamento Autodestrutivo/psicologia , África do Sul/epidemiologia
2.
S Afr Med J ; 109(7): 526-534, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31266581

RESUMO

BACKGROUND: Alcohol use in South Africa (SA) is increasing. The World Health Organization (WHO) states that SA is the third-largest drinking population in Africa, with the highest rate of fetal alcohol syndrome in the world. Internationally, parental drinking during childhood is a risk factor for poor child mental health, behavioural problems and weaker educational outcomes in middle childhood. However, parental alcohol use in Africa is under-researched, and much of the literature on maternal alcohol consumption is restricted to clinical and pregnancy samples. OBJECTIVES: To investigate alcohol use and hazardous drinking (HD) among mothers/primary caregivers of children aged 7 - 11 years in a rural SA cohort. We explored risk factors for drinking and the association between HD and child behaviour/cognition. METHODS: The primary outcome measure was the WHO Alcohol Use Disorder Identification Test (AUDIT) using the standardised cut-off for HD (≥8). Secondary measures were the Patient Health Questionnaire Depression Scale (PHQ-9), Patient Health Questionnaire General Anxiety Disorder Scale (GAD-7), Parenting Stress Index, short form (PSI-36), Child Behaviour Checklist (CBCL, parent reported), Kaufman Developmental Assessment Battery (KABC-II) for child cognition, and Neuropsychological Assessment Battery, 2nd edition, subtests (NEPSY-II) for executive function. We compared characteristics of those drinking/not drinking, using χ2 tests, and modelled outcomes on parenting stress, cognitive outcomes and CBCL scores for children using logistic regression analysis. We grouped mothers/caregivers engaged in HD to examine its effect on parent/child outcomes using t-tests to test for significant differences. RESULTS: Of 1 505 women (1 266 mothers and 239 caregivers) with 1 536 children, 12% reported consuming alcohol and 3% reported HD. Higher maternal/caregiver age (31 - 40 years, adjusted odds ratio (aOR) 0.57 (95% confidence interval (CI) 0.4 - 0.9); >41 years, aOR 0.30 (95% CI 0.2 - 0.5)), education (matriculation, aOR 0.49 (95% CI 0.3 - 0.9); post matriculation, aOR 0.30 (95% CI 0.1 - 0.6)), and a stable relationship with the father (aOR 0.6 (95% CI 0.4 - 1.0)) were associated with no alcohol use. Food insecurity increased the odds of alcohol use (aOR 1.52 (95% CI 1.1 - 2.1)), while parental mental health (parenting stress, anxiety) and child mental health problems were associated with approximately double the odds of consuming alcohol in univariate analysis. Children of HD mothers/caregivers had higher mean scores for psychological problems (CBCL total score: no HD (mean 45.0) v. HD (mean 48.9); p=0.029) and lower cognitive scores (KABC Learning Scale: no HD (mean 14.3) v. HD (mean 12.8); p=0.017). CONCLUSIONS: While HD rates were low, maternal/caregiver alcohol use negatively impacted on parenting and children's behavioural/cognitive outcomes. International evidence suggests that integrated approaches engaging parents and families may be more effective for parent-child outcomes than individual psychiatric or medical care for the parent on their own.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Transtornos do Comportamento Infantil/epidemiologia , Transtornos Cognitivos/epidemiologia , Mães/psicologia , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Ansiedade/psicologia , Cuidadores/psicologia , Criança , Estudos de Coortes , Feminino , Abastecimento de Alimentos , Infecções por HIV/complicações , Humanos , Masculino , Saúde Mental , Transtornos do Neurodesenvolvimento/complicações , Testes Neuropsicológicos , Poder Familiar/psicologia , População Rural , África do Sul/epidemiologia , Estresse Psicológico/etiologia , Inquéritos e Questionários
4.
J Dev Orig Health Dis ; 9(1): 41-57, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28899439

RESUMO

Longitudinal maternal mental health data are needed from high HIV prevalence settings. The Siyakhula Cohort (SC) is a population-based cohort of HIV-positive and negative mothers (n=1506) with HIV-negative children (n=1536) from rural South Africa. SC includes 767 HIV-negative mothers; 465 HIV-positive in pregnancy; 272 HIV-positive since pregnancy (n=2 missing HIV status). A subgroup (n=890) participated in a non-randomized breastfeeding intervention [Vertical Transmission Study (VTS)]; the remaining (n=616) were resident in the same area and received antenatal care at the time of the VTS, but were not part of the VTS, instead receiving the standard of care Prevention of Mother-to-Child Transmission (PMTCT) Programme. In secondary analysis we investigated the prevalence of, and factors associated with, psychological morbidity amongst mothers who were still the primary caregiver of the child (1265 out of 1506) at follow-up (7-11 years post-birth). We measured maternal depression (Patient Health Questionnaire-9), anxiety (General Anxiety Disorder Scale-7) and parenting stress (Parenting Stress Index-36), using standardized cut-offs and algorithms. In total, 75 (5.9%) mothers met criteria for depression, 37 (2.9%) anxiety and 134 (10.6%) parenting stress. Using complete case logistic regression (n=1206 out of 1265 mothers) as compared to being HIV-negative, testing HIV-positive in pregnancy doubled odds of depression [adjusted odd ratios (aOR)=1.96 [1.0-3.7] P=0.039]. Parenting stress was positively associated with acquisition of HIV after pregnancy (aOR=3.11 [1.9-5.2] P<0.001) and exposure to household crime (aOR=2.02 [1.3-3.2] P=0.003); negatively associated with higher maternal education (aOR=0.29 [0.1-0.8] P=0.014), maternal employment (aOR=0.55 [0.3-0.9] P=0.024). Compared with the standard of care PMTCT, VTS mothers had reduced odds of parenting stress (aOR=0.61 [0.4-0.9] P=0.016). Integrating parental support into mostly bio-medical treatment programmes, during and beyond pregnancy, is important.


Assuntos
Ansiedade/psicologia , Depressão/psicologia , Infecções por HIV/psicologia , Poder Familiar/psicologia , Estresse Psicológico/psicologia , Adulto , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Criança , Depressão/diagnóstico , Depressão/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/transmissão , Humanos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Estudos Longitudinais , Masculino , Mães/psicologia , Questionário de Saúde do Paciente , Gravidez , Prevalência , Estudos Prospectivos , População Rural/estatística & dados numéricos , Instituições Acadêmicas , África do Sul/epidemiologia
6.
J Dev Orig Health Dis ; 7(2): 185-96, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26449271

RESUMO

Receiving an education is essential for children living in poverty to fulfil their potential. Success in the early years of schooling is important as children who repeat grade one are particularly at risk for future dropout. We examined early life factors associated with grade repetition through logistic regression and explored reasons for repeating a grade through parent report. In 2012-2014 we re-enrolled children aged 7-11 years in rural KwaZulu-Natal who had been part of an early life intervention. Of the 894 children included, 43.1% had repeated a grade, of which 62.9% were boys. Higher maternal education (aOR 0.44; 95% CI 0.2-0.9) and being further along in the birth order (aOR 0.46; 95% CI 0.3-0.9) reduced the odds of grade repetition. In addition, maternal HIV status had the strongest effect on grade repetition for girls (aOR 2.17; 95% CI 1.3-3.8), whereas for boys, it was a fridge in the household (aOR 0.59; 95% CI 0.4-1.0). Issues with school readiness was the most common reason for repeating a grade according to parental report (126/385, 32.7%), while school disruptions was an important reason among HIV-exposed boys. Further research is needed to elucidate the pathways through which HIV affects girls' educational outcomes and potentially impacts on disrupted schooling for boys. Our results also highlight the importance of preparation for schooling in the early years of life; future research could focus on gaining a better understanding of mechanisms by which to improve early school success, including increased quality of reception year and investigating the protective effect of older siblings.


Assuntos
Desenvolvimento Infantil , Escolaridade , Infecções por HIV/fisiopatologia , Deficiências da Aprendizagem/epidemiologia , Herança Materna , Instituições Acadêmicas , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Intervenção Educacional Precoce , Feminino , HIV/patogenicidade , Infecções por HIV/virologia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , População Rural , Fatores Socioeconômicos , África do Sul/epidemiologia
7.
Tob Control ; 18(1): 64-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19168490

RESUMO

A marked shift in tobacco-related workplace health promotion intervention involves the adoption of policies barring employment to smokers. We discuss the potential public health consequences of these policies on those affected-smokers, their families, the surrounding community and society at large. We find a lack of published evidence evaluating the effectiveness and consequences of these policies. By developing a model of policy effects, we outline possible unintended consequences. With such large gaps in the evidence base and the potential for deleterious consequences, we argue for increased discussion about the use of smoker-free employment policies as a public health intervention and for increased engagement of employers by the public health community in worksite health promotion.


Assuntos
Emprego/legislação & jurisprudência , Política de Saúde/legislação & jurisprudência , Saúde Ocupacional/legislação & jurisprudência , Seleção de Pessoal/legislação & jurisprudência , Fumar/legislação & jurisprudência , Poluição por Fumaça de Tabaco/legislação & jurisprudência , Emprego/ética , Humanos , Transtornos Mentais/etiologia , Modelos Organizacionais , Seleção de Pessoal/ética , Saúde Pública/ética , Saúde Pública/legislação & jurisprudência , Fumar/psicologia , Prevenção do Hábito de Fumar , Estereotipagem , Poluição por Fumaça de Tabaco/ética , Local de Trabalho/legislação & jurisprudência
8.
Lung Cancer ; 28(2): 127-37, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10717330

RESUMO

Retinoic acid receptor beta is the retinoid receptor most frequently associated with the growth suppressive effects of retinoic acid in various epithelial tumor-derived cell lines. In particular, it has been shown that transfection of RARbeta2 in epidermoid lung tumor cells could reduce their in vitro growth rate in the presence of retinoic acid and in vivo tumorigenicity. However, the question remained as to the isoform specificity of this effect. To investigate this, we transfected RARalpha1, RARbeta1 and RARbeta2 into the epidermoid lung cancer cell line Calu-1 and assessed the in vitro growth capacities of the transfected cells. The expression of the fetal RARbeta1 or overexpression of the ubiquitous RARalpha1 isoforms could not mimick the growth suppressive effect of RARbeta2. In addition we analyzed the expression of another RAR isoform, alpha2, in many tumor-derived lines and conclude from its expression pattern that RARalpha2 is unlikely to be involved in retinoic acid growth suppression of lung cancer. Overall our data suggest that the suppressive effect of RARbeta2 is isoform specific.


Assuntos
Carcinoma de Células Pequenas/patologia , Neoplasias Pulmonares/patologia , Receptores do Ácido Retinoico/biossíntese , Tretinoína/farmacologia , Genes Supressores de Tumor/fisiologia , Humanos , Regiões Promotoras Genéticas , Isoformas de Proteínas , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/fisiologia , Transfecção , Células Tumorais Cultivadas
9.
Cell Growth Differ ; 10(11): 729-37, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10593649

RESUMO

We demonstrated previously that loss of in vitro transformation and in vivo tumorigenicity in two independent revertant clones of HeLa cells (designated HA and HF) resulted from dominant-acting genetic changes. Analysis of the p53 tumor suppressor gene revealed stabilization and at least partial restoration of wild-type p53 transactivation properties pathways in both revertants of HPV-induced cell transformation. The half-lives of the p53 protein and both of the HA and HF clones were increased approximately 4 fold compared with the parental HeLa cells (16, 17, and 4 min, respectively). The levels of E6 viral protein expression were similar in the three cell lines, whereas the levels of the ubiquitin ligase protein, E6 associated protein (E6-AP), were elevated in the revertants. Western blot analysis of immunoaffinity-purified p53 demonstrated that stabilization of p53 in the revertants was correlated with a reduction in the in vivo formation of complexes involving the E6 oncoprotein and p53. Stabilization of p53 function in the revertants did not result from mutations in either the p53 or E6-AP genes. Despite the observed stabilization and restoration of p53 transactivation function in the revertants, exposure of the revertants to DNA-damaging agents did not result in elevated levels of p21(waf-1) protein and failed to induce growth arrest in the G1 phase of the cell cycle. However, p53-independent induction of p21(waf-1) protein also failed to induce the G1 phase of the cell cycle. Thus, restoration of wild-type p53 transactivation activity in the HA and HF revertants is insufficient to induce G1 arrest and reversion from HPV-induced cell transformation in our model system.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Transformação Genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Divisão Celular/genética , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Ciclinas/metabolismo , Dactinomicina/farmacologia , Fase G1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor/fisiologia , Células HeLa , Humanos , Ligases/genética , Ligases/metabolismo , Inibidores da Síntese de Ácido Nucleico/farmacologia , Fenótipo , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/genética , Processamento de Proteína Pós-Traducional/fisiologia , RNA Mensageiro/análise , Transcrição Gênica/fisiologia , Ubiquitina-Proteína Ligases , Ubiquitinas/fisiologia
10.
Cancer Res ; 56(21): 4927-35, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8895746

RESUMO

We previously demonstrated that H-ras1 oncogene mutations detected in N-nitroso-N-methylurea (NMU)-induced mammary tumors arose as background mutations within rat mammary cells (RMCs) and that NMU promoted the outgrowth of these preexisting mutants. We have now detected a putative DNA structure in the H-ras1 promoter of RMCs in vivo that was absent in NMU-induced mammary tumor cells. Analysis of the promoter in RMCs as a function of time after exposure to carcinogens indicated that NMU, but not 7,12-dimethylbenz(a)anthracene, initiated the loss of this structure with a half-life of 7 days. Although loss of the structure was irreversible in cells that gave rise to tumors, it was restored in normal RMCs by 120 days after exposure and was present in normal RMCs of animals bearing tumors, even 1 year after NMU exposure. The structure was also abrogated in RMCs during pregnancy and restored after lactation was terminated, suggesting that reversible regulation of the structure by hormones contributed to normal RMC growth. Thus, NMU may promote abnormal RMC growth by mimicking the effects of hormones on DNA conformation. We hypothesize that the NMU-induced alterations in promoter conformation irreversibly deregulates H-ras1 expression in initiated cells, thereby increasing the phenotypic penetrance of the conditional H-ras1 mutations.


Assuntos
Carcinógenos/toxicidade , DNA de Neoplasias/química , Genes ras , Neoplasias Mamárias Experimentais/genética , Metilnitrosoureia/toxicidade , Conformação de Ácido Nucleico/efeitos dos fármacos , Prenhez/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Animais , Metilação de DNA , Feminino , Hormônios Esteroides Gonadais/fisiologia , Neoplasias Mamárias Experimentais/induzido quimicamente , Mutação , Reação em Cadeia da Polimerase , Gravidez , Ratos , Ratos Endogâmicos F344
11.
Cell Growth Differ ; 7(6): 725-35, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8780886

RESUMO

Two nontransformed revertants of HeLa cells, designated HA and HF, were isolated using a selection procedure based on prolonged retention of the fluorescent dye rhodamine 123 within the mitochondria of HeLa (ATCC CCL2) cells versus normal epithelial cells. Unlike the parental HeLa cells, the revertants expressed markedly reduced levels of the bone-liver-kidney, placental, and intestinal isoforms of alkaline phosphatase, exhibited a flat nonrefractile morphology, and failed to grow in suspension culture. The revertant clones had > 100-fold reduced cloning efficiencies in semisolid medium relative to HeLa cells and failed to induce s.c. tumors when injected into nude mice. Both revertant clones have retained nontransformed phenotypes after 5 years of continuous culture. Southern blot analyses performed with human papillomavirus 18-specific DNA probes indicated that the integrated viral sequences present in HeLa cells remained intact in the revertants. Furthermore, the level of the polycistronic mRNAs encoding the viral E6 and E7 oncogenes were comparable in the parental HeLa cell line and the revertants. Western blot analyses of immunoprecipitated human papillomavirus 18 E6 and E7 proteins further demonstrated that the levels of these viral oncoproteins were comparable in HeLa cells and revertants. Infection with helper-free, defective retroviruses that express E6, E7 or E6 and E7 oncogenes failed to retransform the revertants, suggesting that their nontransformed phenotype did not result from mutations in these viral oncogenes. Cell fusion experiments indicated that the revertant phenotypes of HA and HF cells resulted from mutations in cellular genes that activate one or more tumor suppressor genes.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Genes Supressores de Tumor , Neoplasias do Colo do Útero/genética , Animais , Linhagem Celular Transformada , Feminino , Genes Dominantes , Genes Virais , Células HeLa , Humanos , Camundongos , Camundongos Nus , Mutagênese , Oncogenes , Papillomaviridae/genética , Fenótipo , Valores de Referência
12.
EMBO J ; 13(23): 5570-80, 1994 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7988554

RESUMO

Transgenic mice were generated which express a truncated nuclear retinoic acid receptor beta (RAR beta), closely resembling the natural isoform RAR beta 4, under the control of the MMTV promoter. The transgene was expressed in salivary gland, testis, lung and mammary tissue in two different lines. At approximately 11-14 months virtually all the transgenic mice showed hyperplasia of the lung alveolar epithelium with an excess of type II pneumocytes. Hyperplasia of the mammary alveoli and terminal ducts was also seen in some females. Salivary glands and some sebaceous glands were hyperplastic in most male transgenic mice, but only rarely in females or in non-transgenics. Primary benign and malignant tumours were more numerous in transgenic mice than in controls, with a total of 23 in 43 mice versus two in 33 non-transgenic animals. Treatment with dexamethasone to increase transgene expression resulted in exaggerated versions of the above phenotypes. Overexpression of RAR beta 4 therefore appears to predispose various tissues to hyperplasia and neoplasia, and this by contrast to the RAR beta 2 isoform, which has tumour suppressor activity. A survey of ratios of RAR beta 4:RAR beta 2 expression in human lung tumour cell lines showed an increase compared with normal lung tissue, suggesting that RAR beta 4 may play a similar role in human tumorigenesis.


Assuntos
Neoplasias Pulmonares/genética , Neoplasias Mamárias Experimentais/genética , Receptores do Ácido Retinoico/genética , Animais , Sequência de Bases , Primers do DNA , Feminino , Regulação da Expressão Gênica , Humanos , Hiperplasia , Incidência , Pulmão/metabolismo , Pulmão/patologia , Neoplasias Pulmonares/epidemiologia , Masculino , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Neoplasias Mamárias Experimentais/epidemiologia , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Glândulas Salivares/metabolismo , Glândulas Salivares/patologia , Glândulas Sebáceas/metabolismo , Glândulas Sebáceas/patologia , Células Tumorais Cultivadas
13.
Int Immunol ; 6(5): 739-49, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8080843

RESUMO

Using a subtractive strategy, we have cloned an activation-related gene from a human B cell cDNA library. Sequence analysis revealed that this gene was identical to H12.3, a gene belonging to an expanding family of guanine nucleotide-binding protein beta subunits. The expression of H12.3 was inducible in the late phase of mitogen-stimulated T and B cells. In T cells, IL-2 and IL-4 by themselves had no direct effect on the expression of H12.3, but they could augment the level of steady-state H12.3 mRNA stimulated by phytohemagglutinin. On the other hand, IFN-gamma and IL-6 had no obvious effect on the expression in B cells with or without Staphylococcus aureus Cowan I-stimulation. Cyclosporin A, a strong immunosuppressant, inhibited the mitogen-stimulated expression of H12.3, but rapamycin, another such agent, did not. In synchronized Jurkat cells, the expression of H12.3 had no cell cycle-dependent decrease in S and G2/M phase, while cyclin E, which controls the progression of the cell cycle in late G1 phase, did show a periodic expression pattern. The results suggest that H12.3 might be involved in regulation of lymphocyte activation.


Assuntos
Linfócitos B/imunologia , Proteínas de Ligação ao GTP/biossíntese , Expressão Gênica , Ativação Linfocitária , Linfócitos T/imunologia , Animais , Linfócitos B/metabolismo , Ciclo Celular , Células Cultivadas , Clonagem Molecular , Ciclosporina/farmacologia , Proteínas de Ligação ao GTP/genética , Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Fito-Hemaglutininas/farmacologia , Polienos/farmacologia , RNA Mensageiro/metabolismo , Sirolimo , Linfócitos T/metabolismo , Células Tumorais Cultivadas
14.
Cancer Res ; 54(2): 365-9, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8275470

RESUMO

The retinoic acid receptor type beta (RAR beta) complementary DNA from a small cell tumor line was amplified, sequenced, and found to be homologous to the murine RAR beta 1. Seventeen lung tumor lines were analyzed. Five of seven small cell lung carcinoma lines expressed RAR beta 1, but only one other line (epidermoid) expressed the isoform, and this was at trace levels. Two other epidermoid lines, as well as three adenocarcinoma, two adenosquamous, and two large cell-derived lines did not express RAR beta 1. Nine adult human tissues, including lung, were analyzed, and in contrast to what has been reported for the mouse, undetectable or barely detectable levels were observed. On the other hand, a total of 13 different fetal tissues, at three different developmental stages, all expressed RAR beta 1. RAR beta 1 may be a master developmental gene in humans, and the remarkably specific association with small cell lung carcinoma suggests a molecular link between this type of cancer and development.


Assuntos
Carcinoma de Células Pequenas/química , Neoplasias Pulmonares/química , Receptores do Ácido Retinoico/análise , Sequência de Aminoácidos , Sequência de Bases , Química Encefálica , Humanos , Isomerismo , Pulmão/química , Dados de Sequência Molecular , Receptores do Ácido Retinoico/química , Células Tumorais Cultivadas
15.
Proc Natl Acad Sci U S A ; 90(3): 985-9, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8381540

RESUMO

Retinoic acid receptor beta (RAR beta), which codes for a nuclear receptor for retinoic acid, is localized in a chromosomal region frequently deleted in lung cancer cells. The gene is expressed in normal lung tissue and in the majority of the cell lines derived from lung tumors but not in most of the lines derived from lung tumors with epidermoid characteristics. To study the possible role of RAR beta in growth control of epidermoid lung tumor-derived cells, transfectants expresing RAR beta were generated from nonexpressing epidermoid tumor-derived cell lines. Four clones were derived from line CALU-1, three of which showed a 20-60% increase in doubling time in the presence of retinoic acid. Parental and control-transfected cells were unaffected or slightly stimulated. All four clones expressing RAR beta were less tumorigenic in nude mice than were the untransfected or control-transfected cells, with about a 50% incidence of take vs. 95%. When tumors did develop from RAR beta-positive cells, they showed a reduced rate of growth, an increased latency, and, in six of seven tumors tested, a much reduced level of RAR beta expression. Transfectants derived from a second tumor line, H157, also showed a markedly reduced incidence of take in nude mice. Together with the known effects of retinoic acid on differentiation and carcinogenesis, our results support the hypothesis that RAR beta functions as a tumor suppressor gene in epidermoid lung tumorigenesis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Proteínas de Transporte/biossíntese , Genes Supressores de Tumor , Neoplasias Pulmonares/metabolismo , Proteínas de Neoplasias/biossíntese , Tretinoína/metabolismo , Animais , Proteínas de Transporte/genética , Divisão Celular , Humanos , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , RNA Mensageiro/biossíntese , Receptores do Ácido Retinoico , Proteínas Recombinantes/biossíntese , Vírus 40 dos Símios/genética , Transfecção , Tretinoína/farmacologia , Células Tumorais Cultivadas
16.
Genes Chromosomes Cancer ; 3(5): 358-66, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1665705

RESUMO

We report a higher frequency of loss of heterozygosity at loci on the short arm of chromosome 3 in human epidermoid lung tumors than in other non-small cell lung tumors. This observation together with the already known involvement of the retinoids in the development of epidermoid metaplasia and neoplasia, especially in lung tissue, prompted us to investigate by RNAase protection assays the status of expression of a gene that maps on chromosome band 3p24 and codes for the B receptor for retinoic acid (RARB). We show that expression of RARB is detectable in normal lung tissue and in most of the cell lines derived from lung tumors, including the five non-small cell lines that clearly had a non-epidermoid phenotype. Strikingly, however, only one of the five epidermoid-tumor-derived cell lines studied showed detectable expression of RARB. Of two lines derived from adenosquamous tumors, one had a clear epidermoid differentiation, and this line also did not express RARB. Taken together, our results strongly implicate RARB in the evolution of epidermoid lung tumors.


Assuntos
Carcinoma de Células Pequenas/genética , Carcinoma de Células Escamosas/genética , Proteínas de Transporte/genética , Deleção Cromossômica , Cromossomos Humanos Par 3 , Neoplasias Pulmonares/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Heterozigoto , Humanos , Receptores do Ácido Retinoico
17.
Cancer Res ; 48(3): 682-5, 1988 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2891438

RESUMO

Small-cell lung carcinoma (SCLC) is characterized by a consensus deletion in the short arm of chromosome 3. Using a panel of cell lines and somatic cell hybrids containing various rearrangements involving chromosome 3, we have localized the erbA beta sequence (which codes for a thyroid hormone receptor) to the region 3p21----3p25 which overlaps the consensus deletion in SCLC. Moreover, we have shown by Southern blot analysis that at least one copy of the erbA beta sequence is deleted in all six SCLCs so far studied. Normalized ratios of hybridization intensities of the erbA beta probe to intensities of probes for somatostatin (3q28) and raf(3p24-25) ranged from 0.28 to 0.56 and 0.32 to 0.71, respectively, in the six tumors and tumor lines. In view of the importance of the role these genes are known or suspected to play in biological regulation, our results suggest that the erbA beta sequence is a candidate for a recessive oncogene involved in the genesis of SCLC.


Assuntos
Carcinoma de Células Pequenas/genética , Cromossomos Humanos Par 3 , Proteínas de Ligação a DNA/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas/genética , Receptores dos Hormônios Tireóideos/genética , Animais , Deleção Cromossômica , Mapeamento Cromossômico , Humanos , Camundongos , Somatostatina/genética
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