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1.
Clin Cancer Res ; 6(9): 3505-10, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10999736

RESUMO

Allelic losses involving chromosome 3p are frequently observed in cervical cancers. Deletion mapping studies of primary cervical carcinomas have localized common regions of deletion to 3p14.2 and 3p21. The candidate tumor suppressor gene FHIT has been mapped to 3p14.2, and previous studies have demonstrated reduced or aberrant FHIT transcripts and reduced or absent Fhit protein expression in a large percentage of cervical cancer-derived cell lines and primary cervical carcinomas. To expand these observations to preinvasive cervical epithelial lesions and to determine whether loss of Fhit protein expression might be associated with tumor progression, immunohistochemical methods were used to examine Fhit expression in 95 invasive cervical carcinomas, 33 high-grade squamous intraepithelial lesions (HSILs) associated with concurrent invasive cancer, 38 HSILs unassociated with invasive cancer, 24 low-grade squamous intraepithelial lesions, and 22 normal cervix samples. All normal cervical epithelia and low-grade squamous intraepithelial lesions exhibited diffuse cytoplasmic immunostaining of moderate to strong intensity. Fhit protein expression was markedly reduced or absent in 67 of 95 (71%) invasive cancers, 17 of 33 (52%) HSILs associated with invasive cancer, and 8 of 38 (21%) HSILs without associated invasive cancer. The results confirm that Fhit protein expression is reduced or absent in the majority of cervical carcinomas and suggest that loss of Fhit expression often accompanies cervical tumor progression. Moreover, absent or reduced Fhit protein is observed at a significantly higher frequency in HSILs associated with progression to invasive cancer than in HSILs with unknown risk for progression (P = 0.012). These findings suggest that loss of Fhit expression in HSILs could serve as a useful marker of high-grade preinvasive lesions that have an increased likelihood of progression to invasive carcinoma.


Assuntos
Hidrolases Anidrido Ácido , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proteínas de Neoplasias , Biossíntese de Proteínas , Displasia do Colo do Útero/metabolismo , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Invasividade Neoplásica , Proteínas/genética , Neoplasias do Colo do Útero/genética , Displasia do Colo do Útero/genética
2.
Hum Pathol ; 29(4): 359-63, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9563785

RESUMO

Gonadotropin-releasing hormone (GnRH) agonists are commonly used in the treatment of uterine leiomyomas, but little is known about their histological and cellular effects on these neoplasms. We examined a cellular proliferation index as determined by the nuclear antigen Ki-67 and proliferating cell nuclear antigen (PCNA) expression, estrogen receptor (ER), and progesterone receptor (PR) expression in 27 leiomyomas from patients treated with the GnRH agonist leuprolide acetate (LA) and compared them with 33 untreated controls. All leiomyomas were removed by myomectomies from premenopausal woman after 2 to 6 months of LA treatment or in the follicular phase of the menstrual cycle in the untreated controls. Histological features examined included cellularity, nuclear atypia, vascular changes (dilated, thickened, or thrombosed vessels), edema, calcification, hemorrhage, necrosis, hyalinization, and mitotic activity. Although no difference was found between GnRH-treated and nontreated groups with respect to most histological features examined, immunohistochemical studies showed a significant decrease in the cellular proliferation index, ER, and PR expression in the LA-treated cases compared with nontreated controls. The cellular proliferation index, ER, and PR expression decreased by 85%, 49%, and 36%, respectively, in the LA-treated group as compared with controls (P < .001). A subset of cases from the LA-treated and nontreated groups were also analyzed with respect to bcl-2 (an inhibitor of apoptosis) expression, and no significant difference between the LA-treated and nontreated groups was observed with both groups showing a strong (> 75% of cells) cytoplasmic staining pattern. Results of this study show that LA treatment of leiomyomas results in a decrease in number of cycling cells.


Assuntos
Leiomioma/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias Uterinas/metabolismo , Adulto , Antineoplásicos Hormonais/uso terapêutico , Divisão Celular , Feminino , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Leiomioma/tratamento farmacológico , Leiomioma/patologia , Leuprolida/uso terapêutico , Antígeno Nuclear de Célula em Proliferação/metabolismo , Estudos Retrospectivos , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/patologia
3.
Prostate ; 35(1): 50-5, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9537599

RESUMO

BACKGROUND: Reported incidences of various diagnoses made on needle biopsy of the prostate vary significantly in the literature, most of which has originated from large, academic medical centers. METHODS: We recorded all the prostate needle biopsy results from three community hospitals for 1990-1993 to determine the rates of, and trends in, various diagnoses in these practices. RESULTS: Hospital H1 (1,192 cases) halved the rate of atypical, nondefinitive diagnoses from 11.8% in 1990 to 5.7% in 1993 (P < 0.001). The rate at H2 (2,792 cases) remained essentially unchanged at 5.95+/-0.55%, and H3 (1,306 cases) went from 2.3% to 6.0% (0.1 < P < 0.2). In the setting of an atypical, nondefinitive diagnosis, H1 and H2 recommended repeat biopsy less than 7% of the time. H3 made this recommendation in an average of 22.1% of atypical cases. Annual rates of high-grade prostatic intraepithelial neoplasia (PIN) showed no trend over time, and averaged 2.0% (1.2-3.25%) at H1 and 1.2% (0.3-2.0%) at H2. The diagnosis was never made at H3. The fraction of cancers diagnosed as low-grade (Gleason sum < or = 4) showed a statistically significant decreasing trend over time at all three hospitals (P < 0.05). These data are compared with those from the Johns Hopkins Hospital (JHH), a large academic center in geographic proximity to hospitals H1-H3. CONCLUSIONS: At these three community hospitals, we discerned (1) convergence to a rate of approximately 6.0% of atypical, nondefinitive diagnoses; and (2) a progressively more appropriate fraction of carcinomas diagnosed as low-grade on needle biopsy. The rates of diagnosis of high-grade PIN and recommendation of repeat biopsy varied. These rates of PIN, atypical, nondefinitive diagnoses, and low-grade cancer represent an assessment of diagnostic habits.


Assuntos
Biópsia por Agulha , Hospitais Comunitários , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Adenocarcinoma/diagnóstico , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/epidemiologia , Carcinoma in Situ/patologia , Humanos , Masculino , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia
4.
Cancer Res ; 57(21): 4692-8, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9354423

RESUMO

Allelic deletions involving the short arm of chromosome 3 (3p13-21.1) have been observed frequently in cervical carcinomas. Recently, a candidate tumor suppressor gene, FHIT (Fragile Histidine Triad), was cloned and mapped to this chromosomal region (3p14.2). Abnormal FHIT transcripts have been identified previously in a variety of tumor cell lines and primary carcinomas, although their significance and the molecular mechanisms underlying their origin remain incompletely defined. In addition, integration of human papillomavirus DNA has been identified at a fragile site (FRA3B) within the FHIT locus in cervical cancer. These observations motivated us to evaluate FHIT mRNA and protein expression in cervical cancer cell lines, primary cervical carcinomas, and normal tissues. Transcripts of the expected size and sequence were the predominant species identified by reverse transcription (RT)-PCR in cultured keratinocytes and all normal tissues evaluated. In contrast, aberrant FHIT transcripts were readily demonstrated in 6 of 7 cervical carcinoma cell lines and 17 of 25 (68%) primary cervical carcinomas. Northern blot analyses demonstrated reduced or absent FHIT expression in the cervical carcinoma cell lines, particularly those with aberrant RT-PCR products. Immunohistochemical analysis of Fhit expression in cervical tissues revealed strong immunoreactivity in nonneoplastic squamous and glandular cervical epithelium and marked reduction or loss of Fhit protein in 25 of 33 (76%) primary cervical carcinomas. In those cervical cancer cell lines and primary tumors with exclusively aberrant or absent FHIT transcripts by RT-PCR, Fhit protein expression was always markedly reduced or absent. The frequent alterations in FHIT expression in many cervical carcinomas, but not in normal tissues, suggest that FHIT gene alterations may play an important role in cervical tumorigenesis.


Assuntos
Hidrolases Anidrido Ácido , Carcinoma/genética , Cromossomos Humanos Par 3/genética , Deleção de Genes , Genes Supressores de Tumor/genética , Proteínas de Neoplasias , Proteínas/genética , Neoplasias do Colo do Útero/genética , Carcinoma/metabolismo , DNA Complementar/análise , Feminino , Células HeLa , Humanos , Reação em Cadeia da Polimerase , Proteínas/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/metabolismo
5.
J Med Virol ; 44(2): 132-43, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7852953

RESUMO

A Retroviral Coinfection Clinic was established in 1991 at Charity Hospital Medical Center of Louisiana to study patients dually infected with human immunodeficiency virus (HIV) and human T lymphotropic virus (HTLV-I, HTLV-II). Eight patients were evaluated clinically, and by immunological and virological studies. Multiple neuromuscular diseases were observed, including tropical spastic paraparesis, polymyositis, and polyneuropathies. Only one patient developed AIDS. HIV-1 infected patients with HTLV-I, but not HTLV-II, coinfection have maintained stable CD4 counts, despite the fact that quantitative HIV DNA PCR suggests a relatively high copy number. HTLV-I/II antigens were detected in lymphocyte cultures from four patients, and lymphoblastoid cell lines have been established from two. These results support the contention that upregulated HTLV-I/II virus expression and disease manifestations occur during coinfection with HIV, sometimes in association with normal CD4 counts.


Assuntos
Infecções por HIV/complicações , HIV-1 , Infecções por HTLV-I/complicações , Infecções por HTLV-II/complicações , Adulto , Contagem de Linfócito CD4 , Linhagem Celular Transformada , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Infecções por HIV/imunologia , Infecções por HIV/virologia , HIV-1/genética , Infecções por HTLV-I/imunologia , Infecções por HTLV-I/virologia , Infecções por HTLV-II/imunologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Estudos Prospectivos
6.
Neuropharmacology ; 25(8): 833-7, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3022177

RESUMO

The adenylate cyclase (AC) of the neuroblastoma-glioma hybrid cells (NG108-15), is generally considered to be a model for the study of the biochemical correlates of opiate tolerance and dependence. However, the naloxone-induced rebound response of adenylate cyclase, described in some recent reports, is much smaller than that originally described by Sharma, Klee and Nirenberg (1975). Possible explanations for these discrepancies are: (1) a marked down-regulation of opioid receptors and tolerance produced by the use of delta agonists or (2) the use of etorphine, a relatively hydrophobic drug which has slower dissociation rates than morphine. To test these possibilities, neuroblastoma-glioma hybrid cells were treated cells with morphine, etorphine, [D-Ala2,D-Leu5]enkephalin (DADLE), [D-Ala2]Leu-enkephalinamide (DALAMID) or vehicle. In addition, some of the cells treated with etorphine were washed with DADLE to replace the etorphine without producing the rebound response of adenylate cyclase prior to the addition of naloxone. The cells treated with morphine, DADLE and DALAMID, and incubated with prostaglandin E1 (PGE1) and naloxone showed a significant rebound of adenylate cyclase when compared with control groups and opiate-treated cells, incubated only with PGE1. In contrast, naloxone did not induce any significant rebound response in cells treated with etorphine unless they were previously washed with DADLE. These results demonstrate that the lack of a rebound response in cells treated with etorphine was due to the slow dissociation rates of the opiate and not to tolerance or to down-regulation of opioid receptors produced by agonists of high intrinsic activity.


Assuntos
Adenilil Ciclases/metabolismo , Etorfina/farmacologia , Morfinanos/farmacologia , Morfina/farmacologia , Naloxona/farmacologia , Receptores Opioides/efeitos dos fármacos , Alprostadil/farmacologia , Linhagem Celular , Encefalina Leucina/análogos & derivados , Encefalina Leucina/farmacologia , Leucina Encefalina-2-Alanina , Encefalina Metionina/análogos & derivados , Encefalina Metionina/farmacologia , Glioma , Neuroblastoma
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