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1.
J Biol Regul Homeost Agents ; 27(3): 791-804, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24152844

RESUMO

Taking into account the mechanisms at the origin of the airways inflammatory pathologies, our attention has been recently addressed to the study of HMGB1, a protein belonging to the group of alarmins. Alarmins are those molecules which in homeostatic conditions carry out specific metabolic and/or structural functions; furthermore, after a direct trauma or an infection, these molecules are released in the extracellular milieu becoming there activators of the innate immunity and powerful inflammatory factors. In a previous research we found in patients affected with chronic rhinosinusitis with/without nasal polyposis (CRSwNP) an increased expression of this protein in the nucleus of nasal mucosa epithelial cells. HMGB1 was overexpressed also as focal subepithelial infiltration and in the inflammatory cells of patients in comparison with controls. These results suggested a possible pathogenetic role of HMGB1 in CRSwNP. The aim of the present study was to investigate if the expression and localization (nuclear, cytoplasmic and extracellular) of the HMGB1 protein-cytokine is somehow related to the severity and complexity of the histological and clinical picture. We noticed values which have around statistical significance between nuclear HMGB1 and eosinophils infiltrate (p=0.0607) and between nuclear HMGB1 and inflammatory infiltrate (P=0.0524). Even more significant was the correlation between extra-cellular HMGB1 expression and the presence of allergic-hyper reactive conditions such as asthma, allergic rhinitis, NSADs intolerance, antibiotic allergy. HMGB1 was significantly more expressed in the nucleus (p=0.0499) and in the intercellular space (p=0.0380) in allergic patients than in non-allergic subjects and as extra-cellular infiltrate in patients with NSADs intolerance (p=0.0022). These results confirm the role of HMGB1 in the pathogenesis of chronic rhinosinusitis with/without nasal polyposis; besides the higher extra-cellular expression in patients with a more severe clinical and inflammatory picture and the presence of associated co-morbidities suggests to seek for new compounds: these compounds, decreasing the extra-cellular release of this alarmin through a scavenger mechanism, could keep under control the inflammatory process without interfering with the nuclear transcriptional messengers.


Assuntos
Proteína HMGB1/fisiologia , Pólipos Nasais/etiologia , Sinusite/etiologia , Adolescente , Adulto , Idoso , Asma/etiologia , Biomarcadores , Doença Crônica , Feminino , Proteína HMGB1/análise , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/patologia , Rinite Alérgica , Rinite Alérgica Perene/etiologia , Sinusite/patologia
2.
Ghana Med J ; 44(2): 59-63, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21327005

RESUMO

OBJECTIVE: To determine the factors that increase the chances of a woman in Accra having a Pap smear and whether women who have recently visited clinics have higher chances of having had Pap smears. DESIGN: A cross-sectional study METHODS: A representative sample of women in Accra, Ghana was interviewed and the clinical and demographic factors influencing cervical cancer screening was assessed. RESULTS: Out of 1193 women with complete data, only 25 (2.1%) had ever had a Pap smear performed though 171 (14.3%) had their last outpatient clinic visit for either a gynaecological consultation or a regular check up. Simple logistic regression showed that a high educational level, high socioeconomic status and a history over the past month of postmenopausal or intermenstrual bleeding significantly increased the odds of ever having a pap smear. Neither monthly income nor last clinic visit for a gynaecological consultation or regular check up increased the odds of having a pap smear. Multiple logistic regression showed that a high educational level and experiencing postmenopausal or intermenstrual bleeding were the most important determinants of ever having a Pap smear. CONCLUSION: While we wait for a national program for cervical cancer screening, there is a need for clinicians to put more individual effort into ensuring that asymptomatic women are screened for cervical cancer.

3.
J Korean Med Sci ; 16 Suppl: S54-60, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11748377

RESUMO

American ginseng (AG) has been demonstrated to inhibit breast cancer cell growth in vitro. p21 protein, a universal cell cycle inhibitor, binds cyclin-CDK complexes, an important mechanism in cell cycle regulation. The purpose of this investigation was to determine if AG induces p21 gene expression in hormone sensitive (MCF-7) and insensitive (MDA-MB-231) breast cancer cell lines. Cells grown in steroid stripped medium (SSM) were treated with AG, 17-beta-estradiol (E2), genistein or cycloheximide (CHX). Northern blot analyses were performed using human p21Cip1 and 36B4 cDNA probes. Cell lines were transiently transfected with select mouse p21 CAT reporter constructs, including those lacking a p53 binding site. Cell cycle analyses was performed by FACScan. The results revealed that AG induced p21 mRNA expression in MCF-7 and MDA-MB-231 cells (p=0.0004; p < or =0.0001, respectively). Neither E2 nor genistein alter p21 mRNA expression. CHX, a protein synthesis inhibitor, did not block p21 mRNA expression induced by AG, indicating that p21 is induced as an immediate early gene. AG activated p21 reporter constructs in transfected cells, independent of p53 binding sites. The cell cycle proliferative phase was significantly decreased by AG and increased by E2 (p < or =0.0001). AG may inhibit breast cancer cell growth by transcriptional activation of the p21 gene, independent of p53.


Assuntos
Ciclinas/genética , Panax , RNA Mensageiro , Ativação Transcricional , Animais , Sítios de Ligação , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Cloranfenicol O-Acetiltransferase/genética , Inibidor de Quinase Dependente de Ciclina p21 , Feminino , Genes Reporter , Células HT29 , Humanos , Camundongos , Extratos Vegetais/farmacologia , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
4.
Cell ; 100(2): 253-63, 2000 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-10660048

RESUMO

Typical of DNA bacteriophages and herpesviruses, HK97 assembles in two stages: polymerization and maturation. First, capsid protein polymerizes into closed shells; then, these precursors mature into larger, stabler particles. Maturation is initiated by proteolysis, producing a metastable particle primed for expansion-the major structural transition. We induced expansion in vitro by acidic pH and monitored the resulting changes by time-resolved X-ray diffraction and cryo-electron microscopy. The transition, which is not synchronized over the population, proceeds in a series of stochastically triggered subtransitions. Three distinct intermediates were identified, which are comparable to transitional states in protein folding. The intermediates' structures reveal the molecular events occurring during expansion. Integrated into a movie (see Dynamic Visualization below), they show capsid maturation as a dynamic process.


Assuntos
Bacteriófagos/química , Capsídeo/química , Capsídeo/ultraestrutura , Ácidos/farmacologia , Bacteriófagos/crescimento & desenvolvimento , Bacteriófagos/ultraestrutura , Capsídeo/metabolismo , Microscopia Crioeletrônica , Endopeptidases/farmacologia , Concentração de Íons de Hidrogênio , Cinética , Modelos Químicos , Plasmídeos , Dobramento de Proteína , Espalhamento de Radiação , Proteínas do Core Viral/farmacologia , Difração de Raios X
5.
J Bacteriol ; 182(3): 680-8, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10633101

RESUMO

Gene 3 of bacteriophage T4 participates at a late stage in the T4 tail assembly pathway, but the hypothetical protein product, gp3, has never been identified in extracts of infected cells or in any tail assembly intermediate. In order to overcome this difficulty, we expressed gp3 in a high-efficiency plasmid expression vector and subsequently purified it for further analysis. The N-terminal sequence of the purified protein showed that the initial methionine had been removed. Variant C-terminal amino acid sequences were resolved by determining the cysteine content of the protein. The molecular mass of 20.6 kDa for the pure protein was confirmed by Western blotting, using a specific anti-gp3 serum for which the purified protein was the immunogen. We also demonstrated, for the first time, the physical presence of gp3 in the mature T4 phage particle and localized it to the tail tube. By finding a nonleaky, nonpermissive host for a gene 3 mutant, we could clearly demonstrate a new phenotype: the slow, aberrant elongation of the tail tube in the absence of gp3.


Assuntos
Bacteriófago T4/fisiologia , Proteínas de Ligação a DNA/fisiologia , Proteínas Virais/fisiologia , Proteínas Estruturais Virais , Bacteriófago T4/ultraestrutura , Sequência de Bases , Cisteína/análise , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Soros Imunes , Cinética , Microscopia Eletrônica , Dados de Sequência Molecular , Peso Molecular , Desnaturação Proteica , Proteínas Virais/genética , Proteínas Virais/imunologia
6.
J Surg Oncol ; 72(4): 230-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10589039

RESUMO

BACKGROUND AND OBJECTIVES: American ginseng (Panax quinquefolius L.) purportedly alleviates menopause symptoms because of putative estrogenicity. METHODS: Using a standardized American ginseng (AG) extract in MCF-7 breast cancer cells, the objectives were to evaluate the ability of AG to induce the estrogen- regulated gene pS2 by Northern blot analysis, determine the effect on cell growth using the MTT assay, and evaluate the cell cycle effects by flow cytometry. RESULTS: AG and estradiol equivalently induced RNA expression of pS2. AG, in contrast to estradiol, caused a dose-dependent decrease in cell proliferation (P < 0.005). AG had no adverse effect on the cell cycle while estradiol significantly increased the proliferative phase (percent S-phase) and decreased the resting phase (G(0)-G(1) phase) (P < 0.005). Concurrent use of AG and breast cancer therapeutic agents resulted in a significant (P < 0.005) suppression of cell growth for most drugs evaluated. CONCLUSIONS: In vitro use of AG and breast cancer therapeutics synergistically inhibited cancer cell growth.


Assuntos
Neoplasias da Mama/patologia , Medicamentos de Ervas Chinesas/farmacologia , Panax , Plantas Medicinais , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Citometria de Fluxo , Humanos , Paclitaxel/farmacologia , Tamoxifeno/farmacologia , Células Tumorais Cultivadas
7.
Proc Natl Acad Sci U S A ; 95(22): 13141-6, 1998 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-9789055

RESUMO

We conducted a Phase I clinical trial investigating the biologic activity of vaccination with irradiated autologous melanoma cells engineered to secrete human granulocyte-macrophage colony-stimulating factor in patients with metastatic melanoma. Immunization sites were intensely infiltrated with T lymphocytes, dendritic cells, macrophages, and eosinophils in all 21 evaluable patients. Although metastatic lesions resected before vaccination were minimally infiltrated with cells of the immune system in all patients, metastatic lesions resected after vaccination were densely infiltrated with T lymphocytes and plasma cells and showed extensive tumor destruction (at least 80%), fibrosis, and edema in 11 of 16 patients examined. Antimelanoma cytotoxic T cell and antibody responses were associated with tumor destruction. These results demonstrate that vaccination with irradiated autologous melanoma cells engineered to secrete granulocyte-macrophage colony-stimulating factor stimulates potent antitumor immunity in humans with metastatic melanoma.


Assuntos
Vacinas Anticâncer , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Linfócitos/imunologia , Melanoma/imunologia , Melanoma/terapia , Vacinas Anticâncer/efeitos adversos , Citocinas/biossíntese , Citocinas/sangue , Células Dendríticas/imunologia , Células Dendríticas/patologia , Eosinófilos/imunologia , Eosinófilos/patologia , Engenharia Genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Humanos , Hipersensibilidade Tardia , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Macrófagos/imunologia , Macrófagos/patologia , Melanoma/patologia , Metástase Neoplásica , Linfócitos T/imunologia , Linfócitos T/patologia , Transplante Autólogo
8.
Carcinogenesis ; 19(6): 1157-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9667758

RESUMO

H-cadherin is a newly characterized cadherin molecule whose expression is decreased in a variety of human carcinoma cells, suggesting that it may play a role in maintaining normal cellular phenotype. To investigate how re-expression of H-cadherin could influence the malignant phenotype of human breast carcinoma cells in vivo, we transfected both control and H-cadherin expression vectors into human breast cancer cells (MDAMB435), which do not express H-cadherin constitutively. We found that invasiveness of these cells could be prevented by transfection with H-cadherin. We also compared the ability of control- and H-cadherin-transfected cells to induce subcutaneous tumors after injection into mammary fat pads of nude mice. Our results show that H-cadherin transfection produced a marked inhibition of tumor growth and modified the morphology of tumor cells: tumors from mice injected with control cells were significantly larger and contained larger cells having a higher degree of pleomorphism than those of tumors generated from carcinoma cells expressing H-cadherin. Altogether, these results indicate that H-cadherin expression antagonizes tumor growth in nude mice, presumably by enhancing cell-cell association in a tissue environment. These findings strongly suggest that H-cadherin could provide a possible target for corrective gene therapy against breast cancer.


Assuntos
Neoplasias da Mama/patologia , Caderinas/genética , Transformação Celular Neoplásica/genética , Invasividade Neoplásica/genética , Animais , Neoplasias da Mama/genética , Divisão Celular/genética , Feminino , Humanos , Camundongos , Camundongos Nus , Células Tumorais Cultivadas
9.
Cell ; 94(1): 55-60, 1998 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-9674427

RESUMO

The capsid shells of bacteriophage HK97 and several other phages contain polypeptides that are covalently linked into complexes so large that they do not enter polyacrylamide gels after denaturation. The enormous apparent size of these protein complexes in HK97 derives from a novel protein topology. HK97 subunits cross-link via isopeptide bonds into oligomers that are closed rings of five or six members. However, polypeptides from neighboring pentamer and hexamer rings intertwine before the covalent cross-links form. As a result, adjacent protein rings catenate into a network similar to chainmail armor. In vitro linking and unlinking experiments provide strong support for the chainmail model, which explains the unusual properties of these bacteriophages and may apply to other macromolecular structures.


Assuntos
Capsídeo/química , Colífagos/química , Siphoviridae/química , Capsídeo/genética , Colífagos/genética , Colífagos/crescimento & desenvolvimento , Modelos Químicos , Conformação Proteica , Desnaturação Proteica , Siphoviridae/genética , Siphoviridae/crescimento & desenvolvimento
10.
Plast Reconstr Surg ; 102(1): 49-62, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9655407

RESUMO

Skin-sparing mastectomy has been advocated as an oncologically safe approach for the management of patients with early-stage breast cancer that minimizes deformity and improves cosmesis through preservation of the skin envelope of the breast. Because chest wall skin is the most frequent site of local failure after mastectomy, concerns have been raised that inadequate skin excision could result in an increased risk of local recurrence. Precise borders of the skin resection have not been well established, and long-term local recurrence rates after skin-sparing mastectomy are not known. The purpose of this study was to evaluate the oncologic safety and aesthetic results for skin-sparing mastectomy and immediate breast reconstruction with a latissimus dorsi myocutaneous flap and saline breast prosthesis. Fifty-one patients with early-stage breast cancer (26 with ductal carcinoma in situ and 25 with invasive carcinoma) undergoing primary mastectomy and immediate reconstruction with a latissimus flap were studied from 1991 through 1994. For 32 consecutive patients, skin-sparing mastectomy was defined as a 5-mm margin of skin designed around the border of the nipple-areolar complex. After the mastectomy, biopsies were obtained from the remaining native skin flap edges. Patients were followed for 44.8 months. Histologic examination of 114 native skin flap biopsy specimens failed to demonstrate breast ducts in the dermis of any of the 32 consecutive patients studied. One of 26 patients with ductal carcinoma in situ had metastases to the skin of the lateral chest wall and back. Four other patients, one with stage I disease and three with stage II-B disease, had recurrent breast carcinoma. The stage I patient had a local recurrence in the subcutaneous tissues near the mastectomy specimen. Two patients suffered axillary relapse, and one had distant metastases to the spine. The findings of this study support the technique of skin-sparing mastectomy as an oncologically safe one, based on an absence of breast ductal epithelium at the margins of the native skin flaps and a local recurrence rate of 2 percent after 45 months of follow-up. Although these results need to be confirmed with greater numbers of patients and longer follow-up, skin-sparing mastectomy and immediate breast reconstruction may be considered an excellent alternative treatment to breast conservation for patients with ductal carcinoma in situ and early-stage invasive breast cancer.


Assuntos
Neoplasias da Mama/cirurgia , Procedimentos Cirúrgicos Dermatológicos , Estética , Mamoplastia/métodos , Mastectomia/métodos , Adulto , Biópsia , Implantes de Mama , Neoplasias da Mama/patologia , Carcinoma/patologia , Carcinoma/cirurgia , Carcinoma in Situ/secundário , Carcinoma in Situ/cirurgia , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/cirurgia , Feminino , Seguimentos , Humanos , Metástase Linfática/patologia , Músculo Esquelético/transplante , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Mamilos/cirurgia , Fatores de Risco , Segurança , Neoplasias Cutâneas/secundário , Transplante de Pele , Cloreto de Sódio , Neoplasias da Coluna Vertebral/secundário , Retalhos Cirúrgicos
11.
J Immunol ; 158(12): 5619-26, 1997 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9190909

RESUMO

Streptococcal preparation OK-432 is a bacterial immunopotentiator extensively used in Japan for adjuvant cancer therapy. Using a C57BL/6 mouse model, OK-432 was found to induce multiple cytokines including the Th1 polarizing cytokine IL-12. Expression of IL-12 protein by murine splenocytes was restricted to macrophages and B cells and led to high levels of IFN-gamma production from both CD4+ and CD8+ T cells. Of the Th2 cytokines IL-4 and IL-10, only IL-10 protein was detected and originated primarily from the adherent cell population. Its expression was delayed relative to IL-12. A similar pattern of cytokine induction was observed from human PBMCs. OK-432-driven IFN-gamma production was inhibited by anti-IL-12 Ab, anti-IL-2 Ab, anti-TNF-alpha Ab, and anti-IL-2R alpha Ab, suggesting that IFN-gamma production from Th1 cells is induced by the cooperation action of these cytokines through the IL-2R alpha pathway. When compared with another widely used immunopotentiator bacillus Calmette-Guérin (BCG), OK-432 was a stronger IL-12 and IFN-gamma inducer. Furthermore, the mechanism of IFN-gamma induction by OK-432 differed from BCG in that coincident granulocyte-macrophage CSF and IL-1 expression played little to no role. These results suggest that OK-432 is a potent multicytokine inducer, specifically a strong inducer of IL-12, and that OK-432 may exert its antitumor effect by promoting a Th1-dominant state.


Assuntos
Adjuvantes Imunológicos/farmacologia , Antineoplásicos/farmacologia , Interleucina-12/biossíntese , Picibanil/farmacologia , Células Th1/imunologia , Animais , Anticorpos Monoclonais , Células Cultivadas , Humanos , Interferon gama/biossíntese , Leucócitos Mononucleares/imunologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium bovis/imunologia , Baço/citologia
13.
Ann Surg Oncol ; 3(6): 515-20, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8915481

RESUMO

BACKGROUND: Alternative medicines are frequently used by patients with breast cancer for general health benefits. American ginseng, an herbal remedy, purportedly alleviates treatment-induced postmenopausal symptoms. METHODS: Estrogenic potential of American ginseng root extract to induce the expression of pS2, an estrogen-regulated gene, was evaluated in breast cancer cell lines MCF-7, T-47D, and BT-20 by Northern and Western blot analysis. Competitive studies were performed with ginseng in combination with tamoxifen. Cell proliferation assays were performed using the tetrazolium dye procedure and direct cell count. RESULTS: Ginseng and estradiol induce the expression of pS2 RNA and protein in MCF-7 cells, whereas tamoxifen suppresses expression. Neither ginseng nor estradiol induced increased pS2 expression in T-47D or BT-20 cell lines. Although estradiol exhibited a proliferative effect and tamoxifen had an inhibitory effect, ginseng demonstrated no significant effect on cell proliferation. CONCLUSIONS: The results of this study suggest that ginseng may exhibit estrogenlike effects on estrogen receptor-positive breast cancer cells by inducing pS2 expression and that the effect of ginseng may be mediated in part through the estrogen receptor. Because ginseng does not exhibit a proliferative effect, it may play a protective role against breast cancer rather than serve as a mitogen.


Assuntos
Neoplasias da Mama/genética , Estrogênios/metabolismo , Proteínas de Neoplasias/genética , Panax , Plantas Medicinais , Proteínas , Antineoplásicos Hormonais/farmacologia , Divisão Celular/efeitos dos fármacos , Estradiol/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , RNA/análise , Tamoxifeno/farmacologia , Fator Trefoil-1 , Células Tumorais Cultivadas , Proteínas Supressoras de Tumor
14.
Cancer Immunol Immunother ; 42(5): 280-4, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8706049

RESUMO

Although immunotherapy with bacillus Calmette Guérin (BCG) is an established adjuvant treatment for malignant melanoma, the mechanism of its role in this process is unclear. To investigate the possible contribution of tumor-inhibitory cytokines induced by BCG, B16F10 melanoma cell growth in culture was assessed in response to purified cytokines and conditioned media of BCG-stimulated splenocytes. Interferon-gamma (IFN gamma) was the most potent single agent (IC50 approximately 50 pg/ml). Tumor necrosis factor alpha was substantially weaker (IC50 > 10 ng/ml) but provided synergy with IFN gamma. None of the other cytokines such as interleukin-2 (IL-2), IL-4, IL-6, IL-10, IL-12, or granulocyte/macrophage-colony-stimulating factor had direct antitumor activity against B16F10 melanoma cells. However, when IL-2 and/or GM-CSF were combined with BCG either by exogenous addition or through endogenous production by novel cytokine-secreting recombinant BCG (rBCG), a substantial increase in INF gamma production by splenocytes was observed. Antitumor activity of this conditioned medium directly correlated with IFN gamma concentration and was completely blocked by neutralizing antibody to IFN gamma. These results suggest that BCG may exert part of its antitumor action on melanoma through the induction of IFN gamma, which can be greatly enhanced through the concomitant addition of IL-2 and/or GM-CSF. Furthermore, by utilizing rBCG that secrete these cytokines, it may be possible to potentiate the antitumor effect of BCG directly at the site of BCG inoculation.


Assuntos
Vacina BCG/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Interferon gama/biossíntese , Interleucina-2/uso terapêutico , Melanoma Experimental/terapia , Animais , Citocinas/biossíntese , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Interleucina-2/biossíntese , Melanoma Experimental/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/uso terapêutico , Células Tumorais Cultivadas
15.
Tumour Biol ; 17(1): 5-12, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-7501973

RESUMO

P68 is a potent inhibitor of protein synthesis in virally infected cells and has been suggested to function in noninfected cells as a tumor suppressor gene. We have previously demonstrated that p68 expression correlates directly with cellular differentiation and inversely with proliferative activity in normal epithelium and in several human tumor systems. In order to determine the role of p68 in human breast cancer, we utilized immunohistochemistry and mapped the expression of p68 in tissue from 200 breast biopsy specimens. A total of 434 foci, ranging from normal breast tissue to infiltrating carcinoma were examined. We found that p68 was present at basal levels in normal lobular and luminal ductal epithelial cells, with higher levels present in myoepithelial cells. Nonproliferative fibrocystic lesions showed variable expression of p68, with high levels seen within foci of apocrine metaplasia and low levels in cystically dilated terminal duct units. Low levels of p68 were seen in typical ductal proliferations, lobular neoplasia (atypical lobular hyperplasia and lobular carcinoma in situ), and in fibroadenomas. Foci of atypical ductal hyperplasia in situ and invasive ductal carcinoma generally showed higher levels of p68 expression. Among the infiltrating carcinomas, p68 expression correlated with nuclear grade. This suggests that the ability of p68 to inhibit cellular proliferation may be impaired in breast cancer and that its expression, although modestly paralleling cellular differentiation, is not a predictive indicator of improved survival.


Assuntos
Neoplasias da Mama/enzimologia , Mama/enzimologia , Genes Supressores de Tumor , Proteínas Nucleares/genética , Proteínas Quinases , RNA Helicases , Mama/patologia , RNA Helicases DEAD-box , Feminino , Expressão Gênica , Humanos , Hiperplasia/enzimologia , Imuno-Histoquímica , Lesões Pré-Cancerosas/enzimologia , RNA de Cadeia Dupla/metabolismo
16.
N Engl J Med ; 334(3): 143-9, 1996 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-8531968

RESUMO

BACKGROUND: Mutations in a germ-line allele of the BRCA1 gene contribute to the familial breast cancer syndrome. However, the prevalence of these mutations is unknown in women with breast cancer who do not have the features of this familial syndrome. We sought BRCA1 mutations in women who were given a diagnosis of breast cancer at an early age, because early onset is characteristic of a genetic predisposition to cancer. METHODS: Clinical information and peripheral-blood mononuclear cells were obtained from 418 women from the Boston metropolitan area in whom breast cancer was diagnosed at or before the age of 40. A comprehensive BRCA1 mutational analysis, involving automated nucleotide sequencing and a protein-truncation assay, was undertaken in 30 of these women, who had breast cancer before the age of 30. In addition, the BRCA1 mutation 185delAG, which is prevalent in the Ashkenazi Jewish population, was sought with an allele-specific polymerase-chain-reaction assay in 39 Jewish women among the 418 women who had breast cancer at or before the age of 40. RESULTS: Among 30 women with breast cancer before the age of 30, 4 (13 percent) had definite, chain-terminating mutations and 1 had a missense mutation. Two of the four Jewish women in this cohort had the 185delAG mutation. Among the 39 Jewish women with breast cancer at or before the age of 40, 8 (21 percent) carried the 185delAG mutation (95 percent confidence interval, 9 to 36 percent). CONCLUSIONS: Germ-line BRCA1 mutations can be present in young women with breast cancer who do not belong to families with multiple affected members. The specific BRCA1 mutation known as 185delAG is strongly associated with the onset of breast cancer in Jewish women before the age of 40.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Mutação em Linhagem Germinativa , Judeus , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , Adulto , Idade de Início , Proteína BRCA1 , Sequência de Bases , Análise Mutacional de DNA , Feminino , Marcadores Genéticos , Humanos , Dados de Sequência Molecular , Prevalência , Estudos Retrospectivos
17.
Biochemistry ; 34(45): 14918-31, 1995 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-7578104

RESUMO

The 42 kDa capsid protein of bacteriophage HK97 requires the GroEL and GroES chaperonin proteins of its Escherichia coli host to facilitate correct folding, both in vivo and in vitro. In the absence of GroES and ATP, denatured gp5 forms a stable complex with the 14 subunit GroEL molecule. We characterized the electrophoretic and biochemical properties of this complex. In electrophoresis on a native (nondenaturing) gel, the band of the gp5-GroEL complex shifts to a slower migrating position relative to uncomplexed GroEL. The results show that there is only one subunit of gp5 bound to each GroEL 14-mer and that the shift in band position is due primarily to a change in the overall charge of the complex relative to uncomplexed GroEL, and not to a change in size or shape. GroEL forms similar complexes with proteolytic fragments of gp5, with a series of sequence duplication derivatives of gp5, and with other proteins. Electrophoretic examination of these complexes shows that a band shift occurs with proteins larger than 31-33 kDa but not with smaller proteins. For those proteins that cause a band shift upon complex formation, the magnitude of the shift is correlated with the predicted if the charge of the complex were simply the sum of the charge of GroEL and the charge of the substrate protein. We suggest that binding of a substrate protein to GroEL is accompanied by a net binding of solution cations to the complex, but only in the case of proteins above a minimum size of 31-33 kDa. The gp5-GroEL complex is in an association/dissociation equilibrium, with a binding constant measured in the range of 11-17 microM-1.


Assuntos
Capsídeo/química , Chaperonina 60/química , Siphoviridae/química , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/metabolismo , Chaperonina 10/metabolismo , Chaperonina 60/metabolismo , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Guanidina , Guanidinas , Dados de Sequência Molecular , Peso Molecular , Mutagênese Insercional , Peptídeos/metabolismo , Ligação Proteica , Desnaturação Proteica , Dobramento de Proteína , Tripsina/metabolismo
18.
Ann Surg Oncol ; 2(6): 542-9, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8591086

RESUMO

BACKGROUND: Melanoma is the fastest rising cancer in the United States. Bacillus Calmette-Guerin (BCG) has been genetically engineered to actively express and secrete the cytokine interleukin-2 (IL-2). Both BCG and IL-2 have known potent antitumor and immunomodulatory properties. METHODS: This recombinant BCG (rBCG 3A) has been tested as an intratumoral injection and a vaccine therapy in conjunction with irradiated tumor cells against melanoma in the murine B16 melanoma model. RESULTS: The transfection process did not adversely alter the function of the wild-type (WT) BCG. rBCG 3A and WT BCG are equally effective intratumoral and vaccine therapies against melanoma when compared with normal saline control groups. Tumor burdens were significantly smaller (p < or = 0.01 and 0.05) for the treatment groups for both intratumoral and vaccine administration of therapy. Immunization with rBCG 3A and WT BCG 14 days before a B16 challenge resulted in an approximately 45% smaller tumor burden when compared with controls. CONCLUSIONS: Novel therapies based on the immunogenic properties of melanoma combined with molecular technologies may offer promise for an effective and safe treatment of melanoma.


Assuntos
Vacina BCG/uso terapêutico , Melanoma Experimental/terapia , Animais , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/uso terapêutico , Transfecção
19.
Cancer J Sci Am ; 1(1): 55-61, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-9166455

RESUMO

PURPOSE: The optimal treatment of ductal carcinoma in situ is controversial. Traditionally, women with this disease have been treated with mastectomy with excellent results, but recently the need for such extensive surgery has been questioned. Long-term data on the use of conservative surgery and radiation therapy for treatment are limited. A retrospective analysis was performed to assess treatment outcome and prognostic factors for patients with ductal carcinoma in situ treated with conservative surgery and radiotherapy. PATIENTS AND METHODS: From 1976 to 1990, 76 women with ductal carcinoma in situ were treated with conservative surgery followed by radiation therapy. The median age at diagnosis was 48 years. Seventeen patients had a positive family history of breast cancer in a first-degree (n=8) or second-degree (n=9) relative. Median follow-up interval was 74 months for the 71 survivors. In 54 patients, the carcinoma was detected by mammography alone; in 13 patients, by mammography and physical examination; and in 4 patients, by physical examination with a normal mammogram; and in 5 patients, by physical examination alone without mammography. Fifty patients had re-excision after initial biopsy. Final margins were positive in 11, close in 11, negative in 34, and unknown in 20. The median volume of excised tissue was 60 cm3. The axilla was surgically staged in 30 patients (39%) and all were negative. The whole breast was irradiated to a dose of 45 to 50 Gy in all patients. Seventy-two patients also received a boost to the primary site. The median total radiation dose to the primary site was 61 Gy (range, 46 to 71). RESULTS: Seven patients had a recurrence in the treated breast at 16, 18, 41, 63, 72, 83, and 104 months after treatment. The 5- and 10-year actuarial rates of local recurrence were 4% and 15%, respectively. Six of seven recurrences occurred in the vicinity of the original lesion. Four local recurrences were invasive, and three were ductal carcinoma in situ. Two patients developed a contralateral invasive carcinoma. The 5- and 10-year cause-specific survival rates were 100% and 96%, respectively. The 10-year actuarial rate of local recurrence was 25% in the group with a total excision volume less than 60 cm3, as compared with 0% in those with 60 cm3 or more excised (P=0.04). In patients with a positive family history, the 10-year actuarial rate of local recurrence was 37%, as compared with 9% in patients with a negative family history (P=0.008). Of the 17 patients with a positive family history, four developed either an ipsilateral or contralateral invasive breast cancer, whereas 1 of the 58 patients without a family history developed a subsequent invasive breast cancer (P=0.008). CONCLUSION: These results suggest that patients with ductal carcinoma in situ treated with conservative surgery and radiotherapy (including a boost to the primary site) appear to benefit from wide, rather than limited, resection. These results also suggest that family history may be an important prognostic factor for progression of disease.


Assuntos
Neoplasias da Mama/terapia , Carcinoma Intraductal não Infiltrante/terapia , Recidiva Local de Neoplasia , Adulto , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/radioterapia , Carcinoma Intraductal não Infiltrante/cirurgia , Progressão da Doença , Saúde da Família , Feminino , Seguimentos , Humanos , Mastectomia Segmentar , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
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