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1.
Br J Surg ; 90(2): 190-6, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12555295

RESUMO

BACKGROUND: Although much is known about the long-term outcome of patients undergoing left (distal) pancreatectomy for malignancy, comparatively little is known about the optimal management strategy for the residual transected pancreatic parenchyma and the divided pancreatic duct. Clinicopathological and operative factors that may contribute to postoperative pancreatic leak were evaluated. METHODS: A retrospective review of the medical records of 126 patients who underwent left pancreatectomy between June 1990 and December 1999 at the University of Texas M. D. Anderson Cancer Center was performed. RESULTS: Indications for left pancreatectomy included pancreatic neoplasms (n = 42; 33.3 per cent), en bloc resection for management of retroperitoneal sarcoma (n = 21; 16.7 per cent), gastric adenocarcinoma (n = 14; 11.1 per cent), renal cell carcinoma (n = 11; 8.7 per cent) and other tumours or benign conditions (n = 38; 30.2 per cent). Pancreatic parenchymal closure was accomplished by a hand-sewn technique, mechanical stapling, or a combination of the two in 83, 20 and 15 patients respectively. No form of parenchymal closure was used in eight patients. Identification of the pancreatic duct and suture ligation was performed in 73 patients (57.9 per cent). Twenty-five patients (19.8 per cent) developed a pancreatic leak. For subgroups having duct ligation or no duct ligation, pancreatic leak rates were 9.6 per cent (seven of 73 patients) and 34.0 per cent (18 of 53 patients) respectively (P < 0.001). Multivariate analysis including clinicopathological and operative factors indicated that failure to ligate the pancreatic duct was the only feature associated with an increased risk for pancreatic leak (odds ratio 5.0 (95 per cent confidence interval 2.0 to 10.0); P = 0.001). CONCLUSION: Pancreatic leak remains a common complication after left pancreatectomy. The incidence of leak is reduced significantly when the pancreatic duct is identified and directly ligated during left pancreatectomy.


Assuntos
Pancreatectomia/métodos , Ductos Pancreáticos/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Adenocarcinoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Ligadura , Linfa , Masculino , Pessoa de Meia-Idade , Pancreatectomia/efeitos adversos , Neoplasias Pancreáticas/cirurgia , Estudos Prospectivos , Neoplasias Retroperitoneais/cirurgia , Estudos Retrospectivos , Sarcoma/cirurgia , Neoplasias Gástricas/cirurgia
3.
Arch Surg ; 136(5): 528-35, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11343543

RESUMO

HYPOTHESIS: A subset of patients can be identified who will survive without recurrence beyond 5 years after hepatic resection for hepatocellular carcinoma (HCC). DESIGN: A retrospective review of a multi-institutional database of 591 patients who had undergone hepatic resection for HCC and on-site reviews of clinical records and pathology slides. SETTING: All patients had been treated in academic referral centers within university-based hospitals. PATIENTS: We identified 145 patients who had survived for 5 years or longer after hepatic resection for HCC. MAIN OUTCOME MEASURES: Clinical and pathologic factors, as well as scoring of hepatitis and fibrosis in the surrounding liver parenchyma, were assessed for possible association with survival beyond 5 years and cause of death among the 145 five-year survivors. RESULTS: Median additional survival duration longer than 5 years was 4.1 years. Women had significantly longer median additional survival durations than did men (81 months vs 38 months, respectively, after the 5-year mark) (P =.008). Surgical margins, type of resection, an elevated preoperative alpha-fetoprotein level, and the presence of multiple tumors or microscopic vascular invasion had no bearing on survival longer than 5 years. However, patients who survived for 5 years who also had normal underlying liver or minimal fibrosis (score, 0-2) at surgery had significantly longer additional survival than did patients with moderate fibrosis (score, 3-4) or severe fibrosis/cirrhosis (score, 5-6) (P<.001). CONCLUSIONS: Death caused by HCC is rare beyond 5 years after resection of HCC in the absence of fibrosis or cirrhosis. The data suggest that chronic liver disease acts as a field of cancerization contributing to new HCC. These patients may benefit from therapies directed at the underlying liver disease.


Assuntos
Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/mortalidade , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/cirurgia , Feminino , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos
4.
J Gastrointest Surg ; 5(5): 468-76, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11985997

RESUMO

It is not clear whether chronic hepatitis B or C virus (HBV or HCV) infection is a prognostic factor for hepatocellular carcinoma. We performed this study to determine if chronic HBV or HCV infection had any impact on postresection survival or affected patterns of failure. The records of 77 patients undergoing surgical resection for hepatocellular carcinoma between January 1990 and December 1998 were reviewed. Forty-four patients (57%) had HCV infection, 18 patients (23%) had HBV infection, and 15 patients (20%) had negative serology. There were no differences in age, sex, or tumor size among the groups, and all patients had margin-negative resections. There was a significantly higher incidence of satellitosis and vascular invasion in patients with HCV infection (32% and 41% respectively; P <0.05 vs. other groups). With a median follow-up of 30 months, a significantly decreased local disease-free survival (LDFS) was seen in HBV-positive (5-year LDFS 26%) or HCV-positive (5-year LDFS 38%) patients compared to those with negative serology (5-year LDFS 79%; P <0.05). There was also a trend toward a decreased overall survival in patients with positive hepatitis serology compared to patients with negative serology (37% vs. 79%; P = 0.12). Univariate analysis revealed that only satellitosis was related to local recurrence and overall survival. Patients with positive serology for hepatitis B or C undergoing resection for hepatocellular carcinoma have a trend toward worse overall prognosis and a significantly decreased LDFS when compared to patients with negative serology.


Assuntos
Carcinoma Hepatocelular/mortalidade , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Neoplasias Hepáticas/mortalidade , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/cirurgia , Estudos de Casos e Controles , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo
5.
Surgery ; 127(5): 512-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10819059

RESUMO

BACKGROUND: There is no agreement regarding the preoperative measurement of liver volumes and the minimal safe size of the liver remnant after extended hepatectomy. METHODS: In 20 patients with hepatobiliary malignancy and no underlying chronic liver disease, volumetric measurements of the liver remnant (segments 2 and 3 +/- 1) were obtained before extended right lobectomy (right trisegmentectomy). The ratios of future liver remnant to total liver volume were calculated by using a formula based on body surface area. In 12 patients, response to preoperative right trisectoral portal vein embolization was evaluated. In 15 patients who underwent the planned resection, preoperative volumes were correlated with biochemical and clinical outcome parameters. RESULTS: The future liver remnants increased after portal vein embolization (26% versus 36%, P < .01). Smaller size liver remnants were associated with an increase in postoperative liver function tests (P < .05) and longer lengths of hospital stay (P < .02). Preliminary data indicates an increase in major complications for liver volumes < or = 25% (P = .02). CONCLUSIONS: A simple method of measurement provides an assessment of the liver remnant before resection. It is useful in evaluating response to portal vein embolization and in predicating the outcome before extended liver resections.


Assuntos
Hepatectomia/métodos , Fígado/anatomia & histologia , Adulto , Idoso , Criança , Feminino , Humanos , Fígado/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia Computadorizada por Raios X
7.
Ann Surg Oncol ; 6(2): 200-7, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10082047

RESUMO

BACKGROUND: The use of exogenous estrogen has been scrutinized as a risk factor for breast cancer formation. This prospective study addresses the relationship between the use of estrogen replacement therapy and the age of onset of breast cancer. In addition, an analysis of differences in pathological features of breast cancer between estrogen users and non-estrogen-users was evaluated. METHODS: A total of 425 women (age, > or = 50 years) were evaluated during a 4-year period (1994-1997). Data, including the age at diagnosis, method of detection, family history, use of estrogen therapy, and tumor ploidy, S-phase fraction, histological category, estrogen receptor positivity, and grade, were prospectively collected. Data from a control group of 657 women without a diagnosis of breast cancer were obtained from the Evanston Northwestern division of the Women's Health Initiative. Significant associations between the use of estrogen and pathological parameters were determined using the chi2 test and t-test (P < .05). RESULTS: At the time of breast cancer diagnosis, 140 patients were currently receiving estrogen and 202 patients had no history of estrogen use. Eighty-three patients were excluded from analysis (76 patients had a history of previous but not current use of estrogen therapy, four women used only progesterone, and three patients provided incomplete information). There was no difference between patients with breast cancer using estrogen at the time of diagnosis and those with no history of estrogen use with respect to tumor size, age of menopause, family history, mammographic sensitivity, axillary lymph node status, and histological features. Women using estrogen at the time of diagnosis were younger at the time of breast cancer diagnosis, by an average of 5.1 years (61.3 years vs. 66.4 years, P < .001). Women without a history of breast cancer who were receiving estrogen therapy were an average of 2.4 years younger (63.3 years vs. 65.7 years, P < .001) than women without a history of breast cancer who were not receiving estrogen therapy. Patients with breast cancer receiving estrogen also tended to have more grade II tumors (45.9% vs. 36.5%, P = .045) and fewer grade III tumors (25.6% vs. 37.0%, P = .015), compared with women not receiving estrogen therapy at the time of their diagnoses. Estrogen receptor positivity was noted to be more frequent for estrogen users presenting with lobular carcinoma (85% vs. 76%, P = .042) and less frequent for estrogen users presenting with ductal carcinoma (72% vs. 85%, P = .003). CONCLUSIONS: A significantly earlier age of diagnosis for women receiving estrogen therapy suggests that exogenous estrogen may accelerate the pathogenesis of postmenopausal breast cancer. Estrogen therapy may also play a role in altering the grade and estrogen receptor positivity for certain histological types of breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Terapia de Reposição de Estrogênios , Idade de Início , Idoso , Neoplasias da Mama/patologia , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco
8.
J Natl Cancer Inst ; 90(20): 1552-8, 1998 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-9790548

RESUMO

BACKGROUND: Tamoxifen has been shown to promote the growth of human endometrial tumors implanted in athymic mice, and it has been associated with a twofold to threefold increase in endometrial cancer. Toremifene, a chlorinated derivative of tamoxifen, and ICI 182,780, a pure antiestrogen, are two new antiestrogens being developed for the treatment of breast cancer. The effects of these drugs on endometrial cancer are currently unknown. Our objective was to evaluate the effects of toremifene and ICI 182,780 on the growth of human endometrial cancer in athymic mice. METHODS: Athymic, ovariectomized mice were implanted with human endometrial tumors and treated with estrogen, tamoxifen, or the new antiestrogens. RESULTS: The effects of tamoxifen and toremifene on the growth of either tamoxifen-stimulated or tamoxifen-naive endometrial tumors in athymic mice were not substantially different. ICI 182,780 inhibited the growth of tamoxifen-stimulated endometrial cancer, in both the presence and the absence of estrogen. CONCLUSIONS: Toremifene and tamoxifen produce identical effects in our endometrial cancer models. Therefore, it is possible that toremifene, like tamoxifen, may be associated with an increased incidence of endometrial cancer. In contrast, ICI 182,780 inhibited tamoxifen-stimulated endometrial cancer, both in the presence and in the absence of estrogen, suggesting that this drug may be safe with regard to the endometrium, even if it is used following tamoxifen, and that it may not result in an increased incidence of endometrial cancer. Indeed, it is even possible that ICI 182,780 may prove useful as an adjuvant agent in early stage endometrial cancer.


Assuntos
Neoplasias do Endométrio/induzido quimicamente , Estradiol/análogos & derivados , Antagonistas de Estrogênios/efeitos adversos , Tamoxifeno/efeitos adversos , Toremifeno/efeitos adversos , Animais , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Modelos Animais de Doenças , Estradiol/efeitos adversos , Feminino , Fulvestranto , Camundongos , Camundongos Nus , Ovariectomia
9.
Int J Oncol ; 12(5): 981-6, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9538117

RESUMO

It is clear that growth of the MCF-7 breast cancer cell line is stimulated by estrogen and when estrogen is removed, growth slows. We have observed a tumor derived from MCF-7 cells that grows in athymic mice in the absence of estrogen stimulation. We hypothesized that a mutation in the estrogen receptor (ER) could be responsible for this constitutive growth. Using single stranded conformational polymorphism (SSCP) and DNA sequencing analysis, we have identified an ER containing a point mutation at position 415 (gly to val) within the hormone binding domain. The functional activity of this mutant was assessed in vitro and in vivo. Using transient transfection into an ER negative breast cancer cell with an ERE luciferase reporter gene, we found that both the wild-type and mutant receptors have similar efficacy. Additionally, the estrogenic responses were blocked by antiestrogens in a concentration related manner. We also found that tumors with the mutant receptor show similar growth response in athymic mice as wild-type: stimulation with estradiol and inhibition with antiestrogens. We conclude that the point mutation at position 415 (gly to val) is not responsible for constitutive growth.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Mutação Puntual , Receptores de Estrogênio/genética , Transcrição Gênica/efeitos dos fármacos , Animais , Sítios de Ligação , Divisão Celular/efeitos dos fármacos , Primers do DNA , Estradiol/análogos & derivados , Feminino , Fulvestranto , Glicina , Humanos , Luciferases/biossíntese , Camundongos , Camundongos Nus , Ovariectomia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Receptores de Estrogênio/biossíntese , Receptores de Estrogênio/química , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacologia , Transfecção , Transplante Heterólogo , Células Tumorais Cultivadas , Valina
10.
Cancer Treat Res ; 94: 181-93, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9587688
11.
Br J Cancer ; 75(1): 17-27, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9000593

RESUMO

We have cloned and characterized a 77-kDa oestrogen receptor (ER) from an oestrogen-independent subclone of the MCF-7 human breast cancer cell line. This receptor contains an in-frame, tandem duplication of exons 6 and 7, located in the steroid-binding domain of the ER. This mutation has abrogated ligand binding, but not DNA binding, in this mutant ER. We previously described the partial structure of a unique oestrogen receptor (ER) that is expressed in an oestrogen-independent MCF-7:2A subclone of the breast cancer cell line MCF-7 (Pink JJ, Wu SQ, Wolf DM, Bilimoria MM, Jordan VC 1996a, Nucleic Acids Res 24 962-969). Sequence analyses determined the molecular weight of this 80-kDa ER to be 77 kDa, and hereafter this protein will be designated as ER77. Examination of the entire coding sequence of the ER77 mRNA indicates that it contains a tandem duplication of exons 6 and 7. Using a coupled transcription/translation system, a 77-kDa ER, which corresponds to the protein observed in the MCF-7:2A cells, was expressed. The ER77 protein does not bind the ligands [3H] oestradiol or [3H]tamoxifen aziridine. In DNA binding gel shift assays, the in vitro synthesized ER77 binds to a consensus vitellogenin A2 oestrogen-response element. In transient transfection experiments, the mutant ER, alone or in combination with the wild-type ER, does not induce expression of an oestrogen-responsive luciferase reporter construct. In fact, expression of the ER77 in the ER-positive T47D:A18 cell line inhibits E2-induced luciferase expression. Overexpression of wild-type ER in T47D:A18 cells leads to elevated constitutive expression of the luciferase reporter, which was inhibited by co-transfection with ER77. These data suggest that the ER77 can interfere with normal ER activity and does not act as a constitutive activator of oestrogen-independent growth in MCF-7:2A cells. Consequently, the constitutive growth observed in MCF-7:2A cells is probably the result of other ER-mediated pathways.


Assuntos
Células Clonais/metabolismo , Receptores de Estrogênio/isolamento & purificação , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Neoplasias da Mama/química , DNA Complementar/genética , DNA de Neoplasias/química , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Éxons , Feminino , Humanos , Ligantes , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Biossíntese de Proteínas , Receptores de Estrogênio/química , Sequências Repetitivas de Ácido Nucleico , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
12.
Gynecol Oncol ; 63(2): 192-9, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8910626

RESUMO

The majority (60-70%) of endometrial cancers express estrogen receptor. Typically, estrogen-receptor-positive endometrial tumors are associated with a more favorable outcome. Despite this, there is often a discrepancy between estrogen receptor expression and clinical outcome of the disease. Although little is known about the exact role of the estrogen receptor in endometrial malignancies, in breast cancer, where such information is abundant, a number of mutations of the estrogen receptor have been identified. To investigate whether mutations of the estrogen receptor gene occur in endometrial cancers we performed single-stranded conformational polymorphism analysis (SSCP) on 35 human endometrial tumors. We detected four point mutations in three different patients. Interestingly, all the mutations were detected in patients who had aggressive endometrial tumors (grade 3). Although we found the incidence of mutations of the estrogen receptor to be low (8.5%) and thus unlikely to be associated with the majority of endometrial cancers, further investigation is needed to elucidate the role of aberrant estrogen receptor expression in the progression of endometrial malignancies.


Assuntos
Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Mutação Puntual , Receptores de Estrogênio/genética , Análise Mutacional de DNA , DNA Complementar/genética , DNA de Neoplasias/genética , Neoplasias do Endométrio/química , Feminino , Humanos , Pessoa de Meia-Idade , Polimorfismo Conformacional de Fita Simples
13.
Br J Cancer ; 74(8): 1227-36, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8883409

RESUMO

The development of antioestrogen resistance is a major clinical obstacle encountered in the treatment of breast cancer. By long-term growth in oestrogen-free medium, we have derived an oestrogen-independent, anti-oestrogen resistant cell line from the oestrogen receptor (ER)-positive, oestrogen-dependent T47D human breast cancer cell line. This cell line grows maximally in oestrogen-free medium and is resistant to all tested antioestrogens. This cell line does not express any measurable amounts of ER mRNA or protein and, in short-term studies, these cells show no response to either oestrogens or antioestrogens. However, return of these cells to oestrogen-containing medium for more than 8 weeks resulted in the re-expression of ER mRNA and protein. Subsequent limiting dilution subcloning of the T47D:C4 line revealed two phenotypically distinct clones, one which did not express measurable ER after long-term growth in oestrogen-containing medium and one which expressed ER mRNA and protein after a number of weeks in oestrogen-containing medium. In the absence of oestrogen, both types of cells are ER-negative as determined by Northern and Western blotting and lack of any oestrogen-dependent responses. The clone which re-expresses the ER (T47D:C4:5W) now responds to E2 with a 50% increase in growth and a 30-fold induction of an ER-responsive luciferase reporter construct. Long-term growth of the stably ER-negative clone (T47D:C4:2W) causes no measurable oestrogen-mediated responses, as assessed by ER expression, growth stimulation or luciferase induction. Interestingly, ER mRNA can be detected in both cell types by using reverse transcriptase-polymerase chain reaction (RT-PCR). This suggests that the ER mRNA present in the T47D:C4:2W clone is either inefficiently translated or is present at such a low level as to be functionally irrelevant. These novel clonal cell lines will prove to be invaluable in the study of the regulation of ER expression and regulatory pathways leading to oestrogen-independent growth.


Assuntos
Neoplasias da Mama/ultraestrutura , Estrogênios/deficiência , Estrogênios/farmacologia , Receptores de Estrogênio/fisiologia , Southern Blotting , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Polimorfismo Conformacional de Fita Simples , RNA Mensageiro/análise , Células Tumorais Cultivadas
14.
Semin Surg Oncol ; 12(5): 339-45, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8873322

RESUMO

One hundred years ago ovarian ablation was shown to be an effective treatment for advanced breast cancer in premenopausal women. Since that time many different treatment modalities have been advocated to improve patient survival. The value of adjuvant ovarian ablation, however, has recently been established in the overview of breast cancer clinical trials. In fact, comparison of the efficacy of combination chemotherapy with earlier trials of oophorectomy demonstrate the superiority of oophorectomy. The effectiveness of chemotherapy may largely be the result of partial ovarian ablation produced in premenopausal patients. Based on this position, we propose a clinical trial that would establish the optimal therapy for premenopausal breast cancer. In addition, the beneficial effects of long-term tamoxifen as it pertains to serum lipids and bone density are highlighted. The use of tamoxifen maintenance in oophorectomized women might provide an optimal therapy for the control of breast cancer recurrence.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/cirurgia , Ovariectomia , Pré-Menopausa , Tamoxifeno/uso terapêutico , Densidade Óssea/efeitos dos fármacos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Feminino , Humanos , Lipídeos/sangue , Metástase Linfática , Estadiamento de Neoplasias , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Análise de Sobrevida
15.
J Steroid Biochem Mol Biol ; 58(5-6): 479-88, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8918973

RESUMO

The estrogen receptor (ER) contains two transcriptional activation domains: AF-1 and AF-2. AF-2 is dependent on a highly species-conserved region of the ER. It has been shown that site-directed point mutations of conserved hydrophobic amino acids within this region reduce estrogen-dependent transcriptional activation. In addition, when these mutated ERs are transfected into HeLa cells, both tamoxifen and ICI 164,384 become strong agonists. The implication is that mutations in this region could account for the tamoxifen-stimulated tumors seen clinically. We performed single stranded conformational polymorphism (SSCP) analysis spanning the entire ER along with DNA sequencing of the AF-2 region of the ER isolated from two different tamoxifen-stimulated breast cancers, MCF-7/TAM and MCF-7/MT2, and a tamoxifen-stimulated endometrial cancer, EnCa 101. In addition, a tamoxifen-stimulated endometrial carcinoma cell line, the Ishikawa cell line, was also studied. There were no mutations found by SSCP analysis and sequencing of all four AF-2 regions also revealed no mutations. Mutations within the AF-2 region of the human ER do not appear to account for the growth of human breast and endometrial carcinomas that are used as reproducible laboratory models of tamoxifen-stimulated growth observed clinically.


Assuntos
Carcinoma/genética , Neoplasias do Endométrio/genética , Antagonistas de Estrogênios/administração & dosagem , Neoplasias Ovarianas/genética , Receptores de Estrogênio/genética , Tamoxifeno/administração & dosagem , Carcinoma/metabolismo , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Mutação/efeitos dos fármacos , Neoplasias Experimentais/genética , Neoplasias Experimentais/metabolismo , Neoplasias Ovarianas/metabolismo , Receptores de Estrogênio/antagonistas & inibidores , Análise de Sequência de DNA
16.
J Trauma ; 40(6): 1017-20, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8656456

RESUMO

We present a case of "motor-scooter handlebar syndrome," i.e., intimal injury to the common femoral artery caused by a direct blow from a motorcycle handlebar, and review other potential mechanisms for similar arterial injuries. Our case is unique in that a clinical diagnosis was made before vascular studies or arterial occlusion. The mechanism of injury combined with physical examination findings of localized swelling, tenderness, and an overlying bruit prompted early heparinization with subsequent radiographic studies and surgical repair.


Assuntos
Artéria Femoral/lesões , Motocicletas , Ferimentos não Penetrantes/etiologia , Adulto , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Heparina/uso terapêutico , Humanos , Masculino , Radiografia , Ruptura , Síndrome , Ferimentos não Penetrantes/diagnóstico , Ferimentos não Penetrantes/cirurgia
17.
Cancer J Sci Am ; 2(3): 140-50, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9166514

RESUMO

Toxifen, a nonsteroidal antiestrogen, is currently the most widely used adjuvant therapy for the treatment of breast cancer. Though the efficacy of tamoxifen has been well documented in clinical trials, the certainty over the duration of therapy is less clear. Clinical and laboratory evidence suggests that longer therapy is better; however, whether this means 5 years, 10 years, or indefinite therapy has not been established in clinical trials. Essential to any study of long-term tamoxifen therapy is consideration of its effects not only on breast cancer but also on other estrogen target tissues. The estrogenic effect of tamoxifen that lowers serum lipids results in fewer hospital admissions for heart disease and a reduction in fatal myocardial infarction. Similarly, tamoxifen maintains bone mass that may ultimately result in fewer fractures. The effects of tamoxifen appear to parallel the effects of estrogen, so results from clinical trials of estrogen replacement therapy will provide a useful guide of what to expect with tamoxifen. The negative aspect of the therapy is a modest increase in the incidence of endometrial cancer. However, the incidence of endometrial cancer after stopping either estrogen or tamoxifen remains elevated for at least 5 years after the drug is stopped. Nevertheless, it is important to stress that the overall prognosis remains unaffected. We conclude that it will be difficult to demonstrate survival differences between 5 and 10 years of tamoxifen in clinical trials unless significant tamoxifen-stimulated recurrences occur with continued therapy. The benefits of tamoxifen must be calculated using estimates of the decreased rates of heart disease, contralateral cancers, decreased hospitalizations for fractures, and reduced cancer relapses.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Moduladores Seletivos de Receptor Estrogênico/uso terapêutico , Tamoxifeno/uso terapêutico , Animais , Osso e Ossos/efeitos dos fármacos , Doenças Cardiovasculares/prevenção & controle , Quimioterapia Adjuvante , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Lipídeos/sangue , Neoplasias/induzido quimicamente , Osteoporose/prevenção & controle , Medição de Risco , Fatores de Tempo
18.
Nucleic Acids Res ; 24(5): 962-9, 1996 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8600466

RESUMO

Alterations in the amino acid sequence of the estrogen receptor (ER) have been shown to have dramatic effects on its function. Recently, mutant ERs have been isolated from both clinical samples and established breast cancer cell lines, primarily through the use of the polymerase chain reaction (PCR). All previously reported mutations have given rise to either alterations or truncations of the ER protein. We determined the structure of a novel 80 kDa ER which is expressed in an estrogen independent subclone of the MCF-7 human breast cancer cell line (MCF-7:2A). This 80 kDa ER was initially detected by Western blot analysis using a variety of ER specific antibodies. PCR mapping and partial PCR mediated subcloning of the ER cDNA were used to demonstrate that this protein was an ER containing an in-frame duplication of exons 6 and 7. This type of duplication has not been previously described for any members of the steroid receptor superfamily. Karyotype analysis coupled with fluorescence in situ hybridization (FISH) demonstrated that MCF-7:2A cells contained 4-5 copies of the ER gene in contrast to 2 copies in MCF-7:WS8 cells. The ER gene was localized by FISH analyses in both the MCF-7:WS8 and MCF-7:2A cells on chromosome 6, which is the source of the ER in normal human cells. The relative expression level of 2:1 is consistent with DNA gene dosage analysis. Genomic PCR was then used to demonstrate that the 80 kDa ER mRNA was not derived from the trans-splicing of two ER mRNAs but was the result of a genomic rearrangement in which exons 6 and 7 were duplicated in an in-frame fashion. This variant ER may prove to be useful in elucidating the mechanism of estrogen action in breast cancer cells.


Assuntos
Neoplasias da Mama/metabolismo , Éxons/genética , Receptores de Estrogênio/isolamento & purificação , Sequência de Bases , Bandeamento Cromossômico , Mapeamento Cromossômico , Clonagem Molecular , Feminino , Humanos , Dados de Sequência Molecular , Peso Molecular , Receptores de Estrogênio/genética , Células Tumorais Cultivadas
19.
CA Cancer J Clin ; 45(5): 263-78, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7656130

RESUMO

Increased understanding of risk factors for breast cancer, especially the identification of genes associated with a predisposition to breast cancer, has focused attention on the issue of breast cancer prevention. At present, the only clinically available method of breast cancer prevention is prophylactic mastectomy. However, there are no absolute indications for its use, and it is not often appropriate in relation to actual risk for disease. This article reviews what is known about major breast cancer risk factors, reviews the available data on prophylactic mastectomy, and discusses current strategies for the management of the woman at increased risk for breast cancer.


Assuntos
Neoplasias da Mama/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Doenças Mamárias/complicações , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Risco , Fatores de Risco
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