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1.
BJOG ; 118(1): 17-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21091926

RESUMO

OBJECTIVE: To test the feasibility and efficacy of an approach that foregoes the routine use of ultrasound for the determination of eligibility for medical termination of pregnancy. DESIGN: Prospective trial. SETTING: Ten termination of pregnancy clinics in the USA. POPULATION: A total of 4484 women seeking termination of pregnancy with mifepristone-misoprostol. METHODS: Women provided estimates of the date of their last menstrual period and underwent pelvic bimanual and ultrasound examinations. We compared estimates of gestational age using these three methods. MAIN OUTCOME MEASURE: Proportion of women of ≤9 weeks' gestation by woman or provider estimate, but >9 weeks' gestation by ultrasound. RESULTS: The reliance on women's report of their last menstrual period together with physical examination to determine their eligibility for termination of pregnancy with mifepristone-misoprostol would result in few women (63/4008 or 1.6%) accepted for treatment outside the current limits of standard mifepristone-misoprostol regimens used for early termination of pregnancy (i.e. ≤63 days' gestation on ultrasound). CONCLUSIONS: Last menstrual period and physical examination alone, without the routine use of ultrasound, are highly effective for the determination of women's eligibility for early termination of pregnancy with mifepristone-misoprostol.


Assuntos
Abortivos não Esteroides/administração & dosagem , Aborto Induzido/métodos , Mifepristona/administração & dosagem , Misoprostol/administração & dosagem , Quimioterapia Combinada , Estudos de Viabilidade , Feminino , Idade Gestacional , Humanos , Exame Físico , Gravidez , Estudos Prospectivos , Autoadministração , Ultrassonografia Pré-Natal
2.
J Clin Invest ; 102(5): 958-67, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9727064

RESUMO

The parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor (PTHR) functions in skeletal development and mediates an array of other physiological responses modulated by PTH and PTHrP. PTHR gene transcription in mouse is controlled by two promoters: P1, which is highly and selectively active in kidney; and P2, which functions in a variety of tissues. P1 and P2 are conserved in human tissue; however, P1 activity in kidney is weak. We have now identified a third human promoter, P3, which is widely expressed and accounts for approximately 80% of renal PTHR transcripts in the adult. No P3 activity was detected in mouse kidney, indicating that renal PTHR gene expression is controlled by different signals in human and mouse. During development, only P2 is active at midgestation in many human tissues, including calvaria and long bone. This strongly suggests that factors regulating well conserved P2 control PTHR gene expression during skeletal development. Our results indicate that human PTHR gene transcription is upregulated late in development with the induction of both P1 and P3 promoter activities. In addition, P2-specific transcripts are differentially spliced in a number of human cell lines and adult tissues, but not in fetal tissues, giving rise to a shorter and less structured 5' UTR. Thus, our studies show that both human PTHR gene transcription and mRNA splicing are developmentally regulated. Moreover, our data indicate that renal and nonrenal PTHR gene expression are tightly coordinated in humans.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/genética , Regiões Promotoras Genéticas/genética , Receptores de Hormônios Paratireóideos/fisiologia , Regulação para Cima/fisiologia , Osso e Ossos/fisiologia , Células Cultivadas , Clonagem Molecular , Feto/fisiologia , Genes Reporter/genética , Humanos , Rim/fisiologia , Hormônio Paratireóideo/fisiologia , Splicing de RNA/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Hormônio Paratireóideo , Ribonucleases/metabolismo , Análise de Sequência de DNA , Transfecção/genética
3.
Cancer Res ; 56(21): 4865-70, 1996 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-8895735

RESUMO

Recently, we reported that breast cancer cell lines fail to express the gene encoding the fatty acid binding protein mammary derived growth inhibitor (MDGI) and that transfection with an MDGI expression vector results in suppression of the malignant phenotype, suggesting that MDGI is a tumor suppressor gene. We also demonstrated that homozygous deletion and point mutation are not common mechanisms for silencing of the MDGI gene in human breast neoplasms. We now report that hypermethylation of HpaII and HhaI sites upstream of the first exon of the MDGI gene, and a SacII site in the first intron, occurs frequently in human breast cancer cell lines. This distinct methylation pattern is associated with loss of transcription and is reversible by treatment with 5-aza-deoxycytidine. Primary breast tumors also exhibited methylation of the SacII site (19 of 35, 54.3%) and the HpaII and HhaI sites (21 of 35, 66%). Hypermethylation of these sites was correlated with the absence of MDGI mRNA in these tumors. Our results suggest that epimutation of the MDGI gene leads to silencing, which, in turn, may initiate or contribute to progression of breast cancer.


Assuntos
Neoplasias da Mama/genética , Proteínas de Transporte/genética , Inibidores do Crescimento/genética , Azacitidina/farmacologia , Neoplasias da Mama/metabolismo , Metilação de DNA , Proteína 3 Ligante de Ácido Graxo , Proteínas de Ligação a Ácido Graxo , Feminino , Humanos , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
4.
Cancer Res ; 56(16): 3651-4, 1996 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8706001

RESUMO

We demonstrate that although IGF-II gene expression is approximately 3-fold higher in 9,10-dimethyl-1,2-benzanthracine (DMBA)-induced rat mammary tumors (MTs) than in nonneoplastic breast tissue, IGF-II mRNA abundance in DMBA-induced MTs is approximately 130-fold higher in pregnant as compared to nonpregnant hosts. This correlated with accelerated tumor growth in pregnant hosts. Immunohistochemical studies of DMBA-induced MTs with an anti-IGF-II antibody showed an intense staining of tumor cells for IGF-II, whereas a very low staining signal was observed for normal epithelial cells in the lobules. A similar immunostaining pattern was observed in three of three human ductal cancers and adjacent normal breast tissue obtained during pregnancy. DMBA-induced MTs expressed high levels of type I receptor for IGFs as determined by Northern blots. In vitro studies confirmed that IGF-II is a mitogen for neoplastic epithelial cells derived from DMBA-induced MTs. These results demonstrate that hormonal changes associated with pregnancy accelerate breast cancer cell proliferation in the DMBA-induced MT model and suggest that this acceleration is mediated by up-regulation of IGF-II expression within neoplasms.


Assuntos
Regulação Neoplásica da Expressão Gênica , Fator de Crescimento Insulin-Like II/genética , Neoplasias Mamárias Experimentais/metabolismo , Complicações Neoplásicas na Gravidez/metabolismo , 9,10-Dimetil-1,2-benzantraceno , Animais , Divisão Celular , Feminino , Humanos , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Gravidez , RNA Mensageiro/análise , Ratos , Células Tumorais Cultivadas
5.
Cancer Res ; 56(13): 2949-53, 1996 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8674047

RESUMO

Eight different 5'-untranslated region variants of the human growth hormone receptor (hGHR) mRNA have been identified in adult liver (V1-V8). We have compared the expression of two of these variants (V1 and V3) in several human fetal and postnatal tissues (including liver) as well as in hepatoblastomas (HBs) and hepatocellular carcinomas (HCCs). Using reverse transcription-PCR assays, followed by Southern blotting to confirm the specificity of the amplified fragments, we found that V3 was expressed in all fetal and postnatal liver (n = 13 fetal and 5 postnatal), kidney (n = 4 fetal and 4 postnatal), lung (n = 4 fetal and 2 postnatal), intestine (n = 8 fetal and 4 postnatal), skeletal muscle (n = 1 fetal and 1 postnatal), and adrenal (n = 1 fetal and 1 postnatal) samples. In contrast, V1 was expressed only in postnatal liver. We then screened for V1 and V3 in HBs (n = 17, ages 6-36 months, including 5 with paired normal liver), and HCCs (n = 4, ages 50-75 years, with paired normal liver). V1 was undetectable in 15 of 17 HBs, including all HBs paired with (V1-expressing) normal liver; the absence of V1 did not correlate with patient age, sex, HB subtype, +/- chemotherapy, exon 3-retaining and -deficient hGHR mRNA isoform pattern, or loss of heterozygosity at 11p, 1p, and 1q. The four HCCs showed marked (>20-fold; n = 2) or complete (n = 2) suppression of V1 as compared to paired normal liver. V3 was expressed in all HBs, HCCs, and paired normal livers. Interestingly, V3, but not V1, was detected in two Wilms' tumor and paired normal kidney specimens. Our findings suggest that, in the human, there is tissue-, fetal- and tumor-specific regulation of V1 hGHR mRNA.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Regulação Neoplásica da Expressão Gênica , Fígado/embriologia , Fígado/metabolismo , RNA Mensageiro/metabolismo , Receptores da Somatotropina/biossíntese , Adolescente , Adulto , Envelhecimento/metabolismo , Sequência de Bases , Southern Blotting , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Criança , Pré-Escolar , Éxons , Feminino , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Rim/embriologia , Rim/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Receptores da Somatotropina/genética
6.
Cancer Res ; 55(21): 4760-4, 1995 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7585500

RESUMO

Non-small cell lung cancer (N-SCLC) is generally unresponsive to chemotherapy even without previous drug treatment, as opposed to small cell lung cancer (SCLC), which is initially responsive to chemotherapy. The mechanisms of this intrinsic resistance are unknown. This study was designed to investigate the role of DNA repair in intrinsic resistance of N-SCLC to cisplatin. A panel of primary N-SCLC cell cultures and established cell lines were examined and compared to SCLC cell lines established previously from untreated patients. The overall DNA repair capacity was estimated by the ability of cells to reactivate the pRSV-CAT plasmid damaged by cisplatin ("host cell reactivation" assay). Cytotoxicity was determined for cisplatin in vitro. N-SCLC cells were found to be significantly more resistant to cisplatin than SCLC cell lines isolated from untreated patients (P < 0.01). The capacity of N-SCLC cells to reactivate pRSV-CAT plasmid damaged with cisplatin and transfected into cells was higher in N-SCLC cells than in SCLC cells originating from patients who were untreated previously (P < 0.05). Correlation was also observed between chloramphenicol acetyltransferase activity and intrinsic resistance to cisplatin. However, no significant difference was observed between primary N-SCLC cultures and established cell lines. This study indicates that elevated DNA repair capacity is associated with drug resistance in lung cancer and suggests that modulation of DNA repair mechanism(s), such as the incorporation of specific DNA repair inhibitor(s) in therapeutic regimens, may help to improve therapeutic strategies of N-SCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Reparo do DNA , Resistencia a Medicamentos Antineoplásicos/fisiologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Idoso , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Cloranfenicol O-Acetiltransferase/genética , Cisplatino/metabolismo , Cisplatino/farmacologia , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Plasmídeos/efeitos dos fármacos , Plasmídeos/genética , Vírus Sinciciais Respiratórios/genética , Células Tumorais Cultivadas
7.
Cancer Res ; 59(16): 4104-10, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10463615

RESUMO

Gap junctions are intercellular channels that are formed from members of a family of proteins, the connexins (Cxs). Gap junctions play an important role in vital functions, including the regulation of cell growth and cell differentiation. Here, we examined the expression of Cx43, a major Cx in breast tissue, in 32 surgical specimens obtained from breast cancer patients who underwent a primary surgical resection prior to chemotherapy or radiotherapy treatments. The expression of Cx43 gap junctions was compared to the levels of estrogen, progesterone, and erbB2 tyrosine kinase receptors. In addition, a panel of breast cancer cell lines and a series of normal rat mammary tissues and rat mammary tumors induced in vivo by dimethylbenz(a)anthracene were studied. We demonstrated that the lack of Cx43 gap junctions is a common feature of human mammary cancer tissues compared to nonneoplastic breast tissues surrounding primary tumors. Cx43 gap junctions were not observed in ductal carcinomas in situ, infiltrating ductal carcinomas, and infiltrating lobular carcinomas, and they seem to be independent of estrogen, progesterone, and erbB2 receptor status. In breast cancer cell lines and rodent mammary carcinoma tissues, down-regulation of Cx43 occurs at the mRNA level, suggesting a transcriptional mechanism for the decrease of Cx43 protein in breast cancer. In summary, this study provides evidence of decreased expression of Cx43 gap junctions in breast cancer at various stages of progression as well as breast cancer cell lines and raises the possibility that Cx43 may be a useful marker for detecting early oncogenesis in the breast. Because Cx43 gap junctions are lacking in breast cancer and restoration of Cx43 has been shown to reverse the malignant phenotype in vitro, pharmacological up-regulation of Cx43 may prove beneficial in cancer therapeutics.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/metabolismo , Conexina 43/deficiência , Neoplasias Mamárias Animais/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Neoplasias da Mama/patologia , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Mamárias Animais/patologia , Pessoa de Meia-Idade , Ratos , Células Tumorais Cultivadas
8.
Clin Cancer Res ; 4(1): 131-8, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9516961

RESUMO

5-Oxo-L-prolinase (5-OPase) is an enzyme of the gamma-glutamyl cycle involved in the synthesis and metabolism of glutathione (GSH), which is known to protect cells from the cytotoxic effects of chemotherapy and radiation. Previous studies on rats have shown that administration of the cysteine prodrug L-2-oxothiazolidine-4-carboxylate, a 5-oxo-L-proline analogue that is metabolized by 5-OPase, preferentially increases the GSH content of normal tissues while paradoxically decreasing it in the tumor and results in an enhanced in vivo tumor response to the anticancer drug melphalan. These observations initiated the present study of 5-OPase in experimental models and clinical specimens to investigate the potential role of this enzyme in the selective modulation of GSH in normal and tumor tissues. First, 5-OPase activity was measured in tissues of tumor-bearing rats, in the peripheral mononuclear cells of normal human subjects, and in surgically resected tumor and the adjacent normal tissues from patients. We found that the activity of 5-OPase in human kidney, liver, and lung is significantly lower than that found in rats. Second, we have raised a polyclonal IgG anti-5-OPase antibody by immunizing rabbits with purified 5-OPase from rat kidney. This antibody has very high affinity (shown by immunoprecipitation) and specificity (shown by Western blot) and cross-reacts with human 5-OPase (shown by Western blot and immunohistochemistry). It was then used to examine the distribution of 5-OPase in paired normal and neoplastic human specimens using Western blot and immunohistochemistry. Examination of paired normal and neoplastic tissues of stomach and lung revealed a significantly lower level of 5-OPase in tumor tissues than in the paired normal tissues. In colon tissues, there is no significant difference in 5-OPase level between the normal and tumor tissues. These findings could have implications for both carcinogenesis and therapy.


Assuntos
Glutationa/metabolismo , Neoplasias/enzimologia , Piroglutamato Hidrolase/metabolismo , Animais , Feminino , Humanos , Imuno-Histoquímica , Piroglutamato Hidrolase/imunologia , Ácido Pirrolidonocarboxílico , Ratos , Ratos Endogâmicos F344 , Tiazóis/farmacologia , Tiazolidinas
9.
Clin Cancer Res ; 3(5): 661-7, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9815734

RESUMO

Glutathione S-transferase (GST) represents a multifunctional enzyme family consisting of four known cytosolic isoforms (alpha, mu, pi, and Phi) that detoxify a variety of xenobiotic chemicals and may confer resistance to both chemotherapeutic drugs and carcinogens in various experimental models. GST-pi has already been extensively studied in clinical specimens, including breast cancer. We studied the immuno-histochemical distribution and relative immunopositivity of GST-alpha and GST-mu, based on a grading system for immunointensity, in samples of 51 neoplastic and 46 normal breast samples and 12 lymph node metastases from patients treated with intensive chemotherapy and bone marrow transplant. In normal breast tissue, GST-alpha localized predominantly to the cytoplasm of scattered cells lining the luminal aspects of the ducts. Occasional cells showed both cytoplasmic and nuclear GST-alpha immunoreactivity. GST-mu was stained in myoepithelial cells preferentially as well as in occasional ductal cells (including apocrine epithelium), vascular smooth muscle, and plasma cells. GST-alpha and GST-mu were detected in 22 of 51 (43%) and 24 of 48 (50%) invasive cancers, respectively. In paired samples of normal and malignant tissue from the same patient, GST-alpha immunostaining in cancers was significantly less intense compared to that of normal breast tissue in 13 of 41 (32%) cases. No such trend was found for GST-mu in paired samples. Neither GST-alpha nor GST-mu immunopositivity in tumor or nonneoplastic breast was found to correlate with relapse-free or overall survival in this clinical context; however, the apparent decreased expression of GST-alpha in malignant versus normal breast epithelial cells could have important implications in breast carcinogenesis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Neoplasias da Mama/enzimologia , Neoplasias da Mama/terapia , Mama/enzimologia , Glutationa Transferase/análise , Transplante de Células-Tronco Hematopoéticas , Isoenzimas/análise , Adulto , Doenças Mamárias/enzimologia , Doenças Mamárias/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica/métodos , Metástase Linfática , Menopausa , Pessoa de Meia-Idade , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Análise de Sobrevida , Fatores de Tempo
10.
Endocrinology ; 98(4): 910-21, 1976 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-776597

RESUMO

Hypothalamic extracts from frogs (Rana pipiens) were found to contain a significant quantity of immunoreactive LHRH (3.27 +/- 0.63 ng/hypothalamus) (mean +/- SE) measured by radioimmunoassay. In additional radioimmunoassay studies of gross brain LHRH distribution in R. pipiens and R. catesbeiana, 16% of the total frog brain LHRH was located within the telencephalon-septum-optic chiasm regions while the remainder was distributed within the infundibular hypothalamic-pituitary complex. Immunohistochemical studies using the peroxidase-anti-peroxidase (PAP) unlabeled antibody enzyme technique demonstrated the presence of LHRH selectively within some neuronal perikarya located primarily in the median septal nucleus. Fibers containing immunoreactive LHRH were seen in the vicinity of these neuronal cell bodies and in the medial and lateral septal nuclei. In addition, LHRH-containing fibers extended to the median eminence and posterior pituitary, transversing a course beneath the preoptic recess or through the medial forebrain bundle, and then through the lateral infundibular hypothalamus to enter the median eminence bilaterally. LHRH within the median eminence was located in both the inner subependymal and outer glandular zones. On the basis of earlier physiological studies, it is proposed that this LHRH-peptidergic septo-infundibular pathway is involved in control of cyclic gonadotropin activity in the frog.


Assuntos
Encéfalo/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Animais , Feminino , Histocitoquímica , Masculino , Eminência Mediana/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Radioimunoensaio , Rana catesbeiana , Rana pipiens
11.
Endocrinology ; 98(1): 255-8, 1976 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-765116

RESUMO

The distribution of somatostatin was studied in the rat with an immunoperoxidase technique and rabbit anti-somatostatin. Somatostatinergic neurons were identified in the preoptic and anterior periventricular hypothalamus between the anterior commissure, optic chiasm, and the anterior portion of the ventromedial nucleus.


Assuntos
Imunofluorescência , Hipotálamo Anterior/metabolismo , Hipotálamo/metabolismo , Neurônios/metabolismo , Somatostatina/metabolismo , Animais , Feminino , Hormônio do Crescimento/metabolismo , Hipotálamo Anterior/imunologia , Masculino , Neurônios/imunologia , Ratos , Somatostatina/imunologia
12.
Endocrinology ; 142(6): 2409-18, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356689

RESUMO

Estrogens play a role in mammary gland function and are implicated in mammary carcinogenesis. We report the cloning of a novel gene [steroid-sensitive gene 1 (SSG1)] that is regulated by E(2) in the rat uterus and mammary gland. The full-length SSG1 complementary DNA has an open reading frame of 1158 nucleotides encoding a putative protein of 385 amino acids. A SSG1-specific antibody recognizes a 40-kDa protein localized to myoepithelial cells of normal mammary tissue and to endothelial cells of 7,12-dimethylbenz(a)antracene-induced mammary tumors. Treatment of rats with E(2) at 1.2 or 2.4 microg/kg.day for 21 days increases SSG1 protein levels in mammary tissue by 16-fold compared with controls. Removal of E(2) after a 14-day treatment decreases SSG1 protein levels 6-fold and 3-fold at 120 and 144 h, respectively. Treatment of rats with the estrogen antagonists tamoxifen or ICI 182,780 did not affect SSG1 protein levels compared with controls. SSG1 protein levels in 7,12-dimethylbenz(a)antracene-induced rat mammary tumors were 23-fold greater than SSG1 levels in resting mammary tissue, and 8-fold higher than protein levels expressed in lactating mammary glands. We propose that SSG1 plays a role in estrogen functions, and its overexpression is correlated with mammary carcinogenesis.


Assuntos
Clonagem Molecular , Estradiol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Neoplasias Mamárias Experimentais/genética , Proteínas de Neoplasias/genética , 9,10-Dimetil-1,2-benzantraceno , Sequência de Aminoácidos , Animais , Sequência de Bases , Carcinógenos , Endotélio Vascular/química , Feminino , Imunofluorescência , Glândulas Mamárias Animais/irrigação sanguínea , Glândulas Mamárias Animais/química , Glândulas Mamárias Animais/efeitos dos fármacos , Neoplasias Mamárias Experimentais/irrigação sanguínea , Neoplasias Mamárias Experimentais/induzido quimicamente , Dados de Sequência Molecular , Proteínas de Neoplasias/análise , Proteínas de Neoplasias/química , Ovariectomia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Proteínas Supressoras de Tumor
13.
J Clin Endocrinol Metab ; 81(8): 2841-7, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8768840

RESUMO

PTH-related peptide (PTHrP) is the major factor responsible for humoral hypercalcemia of malignancy. This paraneoplastic syndrome has been described in association with a number of malignancies, but rarely with carcinoma of the colon. Moreover, little is known about the molecular mechanisms that underlie PTHrP overexpression in tumors. Here we report a patient who presented with hypercalcemia 6 months after resection of a neuroendocrine colonic carcinoma (tumor I). At the time of admission, intact PTH was decreased, circulating PTHrP levels were elevated, and there was tumor recurrence (tumor II). Immunohistochemical staining of paraffin-embedded sections from tumor I did not stain for PTHrP, whereas cells from tumor II stained intensely positive. Southern blot analysis and differential PCR of genomic DNAs from tumor specimens and the patient's leukocytes demonstrated amplification of the PTHrP gene in tumor II. Moreover, staining for p53 protein was evident in tumor II, but not in tumor I, consistent with the presence of a mutant form of p53 and associated loss of tumor suppressor function in the recurrent tumor. PTHrP gene amplification was also detected in one of five other tumors associated with humoral hypercalcemia of malignancy. These findings suggest that a potential mechanism contributing to PTHrP overexpression in malignancies is gene amplification, which could arise from increased genomic instability associated with the progressive stages of neoplasia.


Assuntos
Carcinoma/genética , Neoplasias do Colo/genética , Amplificação de Genes , Proteínas/genética , Idoso , Sequência de Bases , Southern Blotting , Carcinoma/metabolismo , Carcinoma/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Progressão da Doença , Humanos , Imuno-Histoquímica , Masculino , Sondas Moleculares/genética , Dados de Sequência Molecular , Hormônio Paratireóideo/genética , Proteína Relacionada ao Hormônio Paratireóideo , Reação em Cadeia da Polimerase , Proteína Supressora de Tumor p53/fisiologia
14.
J Mol Endocrinol ; 26(1): 1-10, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11174849

RESUMO

Androgens play an important role in prostate gland development and function, and have been implicated in prostate carcinogenesis. We report the regulation of the gap junctional intercellular communication gene connexin 43 (Cx43) by androgens in the prostate gland. In rat ventral prostate tissue, only trace levels of Cx43 mRNA were detected. Castration, however, resulted in a high increase in Cx43 mRNA and protein. Cx32 was unchanged. Castration-induced Cx43 mRNA and protein were abolished by administration of dihydrotestosterone (DHT). Following castration, prostate weights were approximately 16% of sham-treated controls. However, DHT replacement resulted in prostate weights which were not different from sham-treated controls. Under similar castration conditions, Cx43 induction coincided with pronounced apoptosis in the prostate gland cells, and DHT prevented the induction of apoptosis. Given the physiological role of gap junctions and androgens in the regulation of prostate tissue homeostasis, our observations are relevant to the understanding of androgen-dependent prostate carcinogenesis.


Assuntos
Conexina 43/genética , Regulação da Expressão Gênica , Próstata/metabolismo , Animais , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Masculino , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
15.
Am J Surg Pathol ; 14(11): 1071-5, 1990 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2240356

RESUMO

We report a case of uterine lithiasis in a 73-year-old Latin American woman. The patient underwent vaginal hysterectomy and colporrhaphy for complaints related to secondary uterine prolapse and cystocele. The 70-g, 8 x 5 x 3.5 cm uterus had a normal shape. Ten white, starlike, 0.5 x 0.5 x 0.2 cm, calcified structures were found within the endometrial cavity. Chemical analysis of one of these by x-ray diffraction showed it to be composed of calcite, one of the crystalline forms of calcium carbonate. To our knowledge, this is the first report of human uterine lithiasis in the literature.


Assuntos
Cálculos/patologia , Doenças Uterinas/patologia , Idoso , Feminino , Humanos
16.
Am J Surg Pathol ; 12(4): 251-63, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3354751

RESUMO

Microcystic adenoma (serous cystadenoma) of the pancreas (MA) is an unusual benign tumor of uncertain histogenesis. We have studied 14 cases of MA from 11 women and three men. The average age at diagnosis was 64 years. Six tumors were discovered incidentally. Tumors varied from 2.5 to 12 cm in greatest dimension and all were multicystic; eight tumors were located in the pancreatic head, two in the body, and three in the tail. Each tumor was composed of variably sized cysts lined by simple cuboidal or flattened, focally glycogen-rich epithelium. The stroma was variably collagenized and showed highly vascularized, delicate to broad fibrous septae, which focally contained dystrophic calcification, cholesterol clefts, and hemosiderin. Immunohistochemical studies were performed on eight cases to determine the cell of origin. Epithelial membrane antigen and a low-molecular-weight keratin, detected by monoclonal antibodies PKK1 or AE1/AE3, were diffusely seen in tumor cells of all cases. Tumor cells were uniformly negative for carcinoembryonic antigen, chromogranin, insulin, glucagon, somatostatin, vasoactive intestinal peptide, pancreatic polypeptide, and a low-molecular-weight keratin detected by monoclonal antibody PKK2. Tumor cell antigen reactivity most resembled that seen in normal centroacinar and ductal cells. Electron microscopy of seven cases showed primitive tumor cells with irregularly spaced, short, blunt microvilli, luminal occluding junctions and belt desmosomes, bundles of filaments including dense bodies in both apical and basal cell cytoplasm, sparse organelles, and variable but often pronounced amounts of glycogen. These ultrastructural features most closely resembled the normal pancreatic centroacinar cell. Based on both immunohistochemical and ultrastructural features described above, we conclude that the centroacinar cell is the cell of origin of MA.


Assuntos
Cistadenoma/patologia , Neoplasias Pancreáticas/patologia , Idoso , Cistadenoma/metabolismo , Cistadenoma/ultraestrutura , Feminino , Humanos , Imuno-Histoquímica , Microscopia Eletrônica , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/ultraestrutura
17.
Br J Pharmacol ; 127(5): 1165-76, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10455263

RESUMO

Adrenoreceptor agonists induce a hypertrophic phenotype in vitro and in vivo. To investigate the molecular remodeling in chronic cardiac hypertrophy we infused adult male mice with vehicle. isoproterenol, phenylephrine or both agonists for 3, 7 or 14 days. All drugs increased cardiac mass. After minipump removal cardiac mass regressed to control levels within 7 days after PE and ISO treatment whereas ISO + PE treated hearts were incompletely regressed. ANF and beta-MHC, but not alpha-MHC, expression were increased by agonists at all time points. GATA-4, Nkx-2.5, Egr-1, c-jun and c-fos expression were increased after 3, 7 and 14 days of treatment. Expression was greatest after ISO+PE> >ISO>PE>vehicle infusion suggesting a synergistic effect of adrenoreceptor stimulation and indicating a greater effect of beta- than alpha-adrenergic action in vivo. After PE or ISO drug withdrawal the HW/BW was normal and Egr-1, c-jun, c-fos and GATA-4, but not Nkx2.5, expression dropped to control levels. HW/BW regression was incomplete after ISO+PE and elevated levels of Egr-1, c-jun and Nkx2.5 expression remained. A hydralazine-mediated reduction in blood pressure had no effect on the agonist-induced cardiac hypertrophy or gene expression. In conclusion, we found that continued agonist stimulation, and not blood pressure. is responsible for the maintained increase in gene expression. Further, we found the decrease in gene expression in the regression after drug withdrawal was gene specific.


Assuntos
Cardiomegalia/metabolismo , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Genes Precoces , Proteínas de Homeodomínio/genética , Receptores Adrenérgicos/fisiologia , Fatores de Transcrição/genética , Proteínas de Xenopus , Animais , Anti-Hipertensivos/farmacologia , Fator Natriurético Atrial/biossíntese , Cardiomegalia/induzido quimicamente , Fator de Transcrição GATA4 , Proteína Homeobox Nkx-2.5 , Isoproterenol/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cadeias Pesadas de Miosina/biossíntese , Fenilefrina/farmacologia , Fatores de Transcrição/biossíntese
18.
J Endocrinol ; 171(1): 109-18, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11572795

RESUMO

Prostate cancer is the most diagnosed invasive malignancy in males. Androgens and oestrogens have been implicated in the pathogenesis of prostate cancer. We report herein that the pure anti-oestrogen ICI 182,780 (ICI) reduces Ki-67 labelling index and IGF-I receptor levels in rat prostate. Increase of IGF-I mRNA and IGF-binding protein 3 (IGFBP-3) accumulation occur without any effect on prostate weight. Finasteride significantly decreases prostate weight and inhibits IGF-I gene expression. IGFBP-3 mRNA, Akt and phospho-Akt are not affected by finasteride. Co-administration of ICI plus finasteride reduces prostate weight by approximately 50% and causes acinar dilation with decreased luminal epithelial cell thickness. The acinar epithelial cells became atrophic and inactive with minimal cytoplasm. We also demonstrate a synergistic effect of ICI and finasteride on induction of IGFBP-3 accumulation and inhibition of Akt phosphorylation. Because the IGF and IGFBP-3 system plays an important role in prostate epithelial cell proliferation, apoptosis and tumour progression, the inhibitory effects of finasteride and ICI on IGF system may contribute to their anti-proliferative activity. These observations support a potential use of ICI in conjunction with finasteride in the prevention and/or treatment of prostate cancer.


Assuntos
Inibidores de 5-alfa Redutase , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Finasterida/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Próstata/metabolismo , Proteínas Serina-Treonina Quinases , Animais , Northern Blotting/métodos , Divisão Celular/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Células Epiteliais/efeitos dos fármacos , Fulvestranto , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fosforilação , Próstata/anatomia & histologia , Próstata/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Ratos , Receptor IGF Tipo 1/metabolismo , Estatísticas não Paramétricas
19.
Hum Pathol ; 7(6): 709-18, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-992650

RESUMO

This report concerns a young woman who, after taking a contraceptive preparation orally for three years, developed the Budd-Chiari syndrome as the result of a widespread chronic obliterative process involving the intrahepatic efferent venous system. Her prolonged course, which failed to respond to an end-to-side portacaval shunt procedure, mimicked chronic hepatitis evolving to cirrhosis. Additional noteworthy features were the presence of two small benign hepatic adenomas, observed both at biopsy and at necropsy, a lesion recently recognized as a complication of anovulatory drugs, and widespread hepatic calcifications found at autopsy.


Assuntos
Síndrome de Budd-Chiari/induzido quimicamente , Anticoncepcionais Orais Sintéticos/efeitos adversos , Anticoncepcionais Orais/efeitos adversos , Mestranol/efeitos adversos , Adenoma/induzido quimicamente , Adulto , Autopsia , Síndrome de Budd-Chiari/patologia , Feminino , Humanos , Neoplasias Hepáticas/induzido quimicamente , Noretandrolona/efeitos adversos , Gravidez
20.
Hum Pathol ; 7(5): 595-604, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-987011

RESUMO

A case is herin reported of a primary gastric choriocarcinoma occurring in an elderly woman associated with very high titers of circulating chorionic gonadotropin. Unlike the majority of previously reported cases, in which adenocarcinomatous components were present, the tumor in this case was purely trophoblastic. The clinicopathologic findings of the previously reported cases are summarized, along with the various theories of histogenesis.


Assuntos
Coriocarcinoma/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Coriocarcinoma/sangue , Gonadotropina Coriônica/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Neoplasias Gástricas/sangue
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