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1.
Cancer ; 106(5): 1065-77, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16456813

RESUMO

BACKGROUND: To date, several mechanisms have been described by which malignant cells escape from the immune system. One of these is through the expression of FasL. The authors hypothesized that the Fas/FasL interaction enables cervical carcinoma cells to induce apoptosis of the cells of the immune system and thereby escape from them. METHODS: The authors tested the expression of FASL on the surface of cervical carcinoma tissues. Next, they stained the same cervical tissues with anti-human leukocyte common antigen and TUNEL to identify apoptotic cells. An in vitro functional assay was then done to test if the FASL expressed on the surface of cervical carcinoma cell lines was or was not responsible for inducing apoptosis in T-cells. Finally, they compared the expression of FASL on normal and dysplastic cervical tissues. RESULTS: Ninety-four percent of the cervical carcinoma tissues the authors tested expressed FasL and the majority of the apoptotic cells in the specimens were leukocytes with very few tumor cells. In the in vitro functional assay, only the Fasl expressing cell line and not the Fasl negative cell line was able to induce apoptosis of the Fas-expressing Jurkat cells. On examining the normal cervical tissues, the authors found that the expression of Fasl was confined to the basal cell layer with loss of expression observed in the suprabasal layers, which made it an immune privileged site. Conversely, there was persistent expression of FasL in the dysplastic layers in cervical dysplasia and squamous cell carcinoma specimens. CONCLUSIONS: The findings of the current study support the authors' hypothesis that persistent expression of FasL plays a role in the ability of cervical carcinoma cells to escape from the immune system.


Assuntos
Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/fisiopatologia , Glicoproteínas de Membrana/biossíntese , Evasão Tumoral , Fatores de Necrose Tumoral/biossíntese , Displasia do Colo do Útero/imunologia , Displasia do Colo do Útero/fisiopatologia , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/fisiopatologia , Apoptose , Carcinoma de Células Escamosas/genética , Colo do Útero/fisiologia , Proteína Ligante Fas , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Leucócitos , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/genética , Displasia do Colo do Útero/genética
2.
Cancer Biol Ther ; 5(1): 22-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16357512

RESUMO

PURPOSE: To determine the maximum-tolerated dose (MTD) and toxicity profile of the novel anticancer agent, 2-methoxyestradiol (2ME2) administered orally, in patients with solid tumors. MATERIALS AND METHODS: Twenty patients with refractory solid tumors were enrolled. 2ME2 was given orally starting at 400 mg bid with dose escalation until 3000 mg bid. Tumor biopsies were taken before and after starting the drug to assess for microvessel density by CD 31 and cell proliferation by Ki67 immunohistochemistry. Serial plasma samples collected up to 50 hours after first single oral dose for characterization of pharmacokinetics, were analyzed using liquid chromatography tandem mass-spectrometry. RESULTS: Eleven men and nine women received 2ME2 at dose levels of 400 mg bid (n = 3), 800 mg bid (n = 3), 1600 mg bid (n = 6), 2200 mg bid (n = 5) and 3000 mg bid (n = 3). There were no dose limiting toxicities, therefore the MTD was not defined. There was one episode of grade 4 angioedema in the 1600 mg bid dose level 38 days into 2ME2 treatment. Other toxicities were mild to moderate. A patient with clear cell carcinoma of the ovary had a partial response at 1600 mg bid dose level lasting over three years. CONCLUSION: MTD for 2ME2 was not reached at dose of 3000 mg bid. The trial was closed due to extremely low plasma concentrations of 2ME2 relative to the doses administered. 2ME2 treatment had no effect on microvessel density (CD31 immunostaining) and cell proliferation (Ki-67 immunostaining). A new formulation of 2ME2 with improved bioavailability is currently being developed.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Antineoplásicos/uso terapêutico , Estradiol/análogos & derivados , Dose Máxima Tolerável , Neoplasias/tratamento farmacológico , 2-Metoxiestradiol , Administração Oral , Adulto , Apoptose , Capilares/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Estradiol/efeitos adversos , Estradiol/sangue , Estradiol/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/diagnóstico por imagem , Tomografia Computadorizada por Raios X
3.
J Urol ; 173(3): 790-6, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15711271

RESUMO

PURPOSE: Alendronate (AL), a potent oral bisphosphonate, blocks the secretion of matrix metalloproteinase-2 and the establishment of bone metastases in animal models. Ketoconazole (KT) has demonstrated activity in androgen independent prostate cancer (AIPC). In this study we determined whether KT plus AL produced acceptable disease responses compared with KT alone. As the experimental design, 72 patients with progressive AIPC metastatic to bone were randomized to receive KT (1,200 mg daily) plus hydrocortisone (H) (30 mg daily) with or without AL (40 mg daily). Prostate specific antigen (PSA) consensus criteria and radiographic scans were used to determine the proportion of patients with a PSA decrease, time to progression and response duration. The pharmacokinetics of KT and AL were characterized and changes in circulating angiogenic factors were assessed. RESULTS: At a median potential followup of 23.9 months the proportion of patients with a greater than 50% decrease in PSA was similar in the KT/H/AL and KT/H, groups (50% and 47%, respectively). The median duration of response was 8.9 and 6.3 months in the KT/H/AL and KT/H groups, respectively (p = 0.125). Median progression-free survival was not significantly prolonged in the KT/H/AL group (4.6 vs 3.8 months, p = 0.27). There was no significant difference in overall survival between the 2 treatment arms but there was a trend toward improved survival in the KT/H arm (p = 0.074). Toxicity in the 2 groups was mild and there were no clear associations between changes in circulating angiogenic factor levels and clinical outcomes in either treatment arm. CONCLUSIONS: There were no statistically significant differences in response rate, progression-free survival or overall survival between KT/H alone and KT/H plus AL treatment in patients with AIPC. The addition of AL to KT/H may increase the response duration with an acceptable safety profile compared with treatment with KT/H alone. However, the addition of AL offers no survival benefit in patients with AIPC.


Assuntos
Alendronato/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Cetoconazol/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Idoso , Alendronato/farmacocinética , Neoplasias Ósseas/sangue , Quimioterapia Combinada , Humanos , Cetoconazol/farmacocinética , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/sangue
4.
Clin Cancer Res ; 10(15): 5038-47, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15297405

RESUMO

PURPOSE: The purpose of this study was to determine the toxicities and characterize the pharmacokinetics of docetaxel and flavopiridol in patients with metastatic breast cancer. EXPERIMENTAL DESIGN: Docetaxel was administered at an initial dose of 60 mg/m(2) followed in 24 hours by a 72-hour infusion of flavopiridol at 50 mg/m(2)/d every 3 weeks. Because dose-limiting myelosuppression occurred, the schedule was amended to docetaxel, 50 mg/m(2), followed by escalating doses of flavopiridol (starting dose, 26 mg/m(2)/d) as a 1-hour infusion daily for 3 days. Pharmacokinetic studies were performed. Ki67, p53, and phosphorylated retinoblastoma protein (phospho-Rb) in paired tumor and buccal mucosa biopsies (obtained pre- and posttreatment) were examined by immunohistochemistry. RESULTS: Eleven patients were enrolled. Five patients received docetaxel and 72-hour flavopiridol. Dose-limiting toxicity was grade 4 neutropenia. Six patients received docetaxel and 1-hour flavopiridol, and the dose-limiting toxicity was grade 3 hypotension. Pharmacokinetics of flavopiridol and docetaxel were consistent with historical data. Nuclear staining with p53 increased and phospho-Rb decreased in 10 pairs of buccal mucosa biopsies posttreatment (P = 0.002 and P = 0.04, respectively). No significant changes in Ki67, p53, or phospho-Rb were detected in six paired tumors. Two patients sustained stable disease for >3 months (72-hour flavopiridol), and one partial response was observed (1-hour flavopiridol). CONCLUSIONS: Docetaxel combined with 72-hour flavopiridol was not feasible because of dose-limiting neutropenia. Dose escalation of a 1-hour infusion of flavopiridol with docetaxel was also not possible. The changes in p53 and phospho-Rb in buccal mucosa suggest that a biological effect with flavopiridol was achieved.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores Enzimáticos/administração & dosagem , Flavonoides/administração & dosagem , Piperidinas/administração & dosagem , Taxoides/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Área Sob a Curva , Biomarcadores Tumorais/metabolismo , Biópsia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ensaios Clínicos como Assunto , Docetaxel , Feminino , Flavonoides/efeitos adversos , Humanos , Imuno-Histoquímica , Antígeno Ki-67/biossíntese , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Mucosa/patologia , Metástase Neoplásica , Fosforilação , Piperidinas/efeitos adversos , Proteína do Retinoblastoma/biossíntese , Taxoides/efeitos adversos , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo
5.
J Clin Oncol ; 22(15): 3080-90, 2004 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-15284258

RESUMO

PURPOSE: To evaluate changes in epidermal growth factor receptor (EGFR) phosphorylation and its downstream signaling in tumor and surrogate tissue biopsies in patients with metastatic breast cancer treated with erlotinib, an EGFR tyrosine kinase inhibitor, and to assess relationships between biomarkers in tumor and normal tissues and between biomarkers and pharmacokinetics. PATIENTS AND METHODS: Eighteen patients were treated orally with 150 mg/d of erlotinib. Ki67, EGFR, phosphorylated EGFR (pEGFR), phosphorylated mitogen-activated protein kinase (pMAPK), and phosphorylated AKT (pAKT) in 15 paired tumor, skin, and buccal mucosa biopsies (at baseline and after 1 month of therapy) were examined by immunohistochemistry and analyzed quantitatively. Pharmacokinetic sampling was also obtained. RESULTS: The stratum corneum layer and Ki67 in keratinocytes of the epidermis in 15 paired skin biopsies significantly decreased after treatment (P = .0005 and P = .0003, respectively). No significant change in Ki67 was detected in 15 tumors, and no responses were observed. One was EGFR-positive and displayed heterogeneous expression of the receptor, and 14 were EGFR-negative. In the EGFR-positive tumor, pEGFR, pMAPK, and pAKT were reduced after treatment. Paradoxically, pEGFR was increased in EGFR-negative tumors post-treatment (P = .001). Although markers were reduced in surrogate and tumor tissues in the patient with EGFR-positive tumor, no apparent associations were observed in patients with EGFR-negative tumor. CONCLUSION: Erlotinib has inhibitory biologic effects on normal surrogate tissues and on an EGFR-positive tumor. The lack of reduced tumor proliferation may be attributed to the heterogeneous expression of receptor in the EGFR-positive patient and absence of target in this cohort of heavily pretreated patients.


Assuntos
Neoplasias da Mama/metabolismo , Inibidores Enzimáticos/farmacocinética , Receptores ErbB/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinazolinas/farmacocinética , Administração Oral , Biomarcadores/análise , Neoplasias da Mama/tratamento farmacológico , Determinação de Ponto Final , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Cloridrato de Erlotinib , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Mucosa Bucal/metabolismo , Metástase Neoplásica , Fosforilação , Projetos Piloto , Quinazolinas/administração & dosagem , Quinazolinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Pele/metabolismo , Tomografia Computadorizada de Emissão
6.
J Clin Oncol ; 21(2): 241-50, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12525515

RESUMO

PURPOSE: To define the value of thymidylate synthase (TS), Ki-67, and p53 as prognostic markers in patients with stage II and III colon carcinoma. PATIENTS AND METHODS: We retrospectively analyzed the prognostic value of TS, Ki-67, and p53 in 706 patients with Dukes' B (291 patients) or Dukes' C (415 patients) colon carcinoma who were treated with either surgery alone (275 patients) or surgery plus fluorouracil (FU)-leucovorin chemotherapy (431 patients) in National Surgical Adjuvant Breast and Bowel Project (NSABP) protocols C01-C04. All three markers were assayed using immunohistochemical techniques. RESULTS: Using 5 years of follow-up data, our retrospective analysis demonstrated an association between TS intensity (relapse-free survival [RFS]: risk ratio [RR] = 1.46, P =.01; overall survival [OS]: RR = 1.54, P =.002), Ki-67 (RFS: RR = 0.76, P =.05; OS: RR = 0.62, P =.001), and p53 (RFS: RR = 1.49, P =.01; OS: RR = 1.21, P =.18) for RFS and OS. High TS intensity levels and positive p53 staining were associated with a worse outcome. Tumors containing a high percentage of Ki-67-positive cells enjoyed an improved outcome compared with those patients whose tumors contained relatively few positive cells. An interaction with treatment was not identified for any of the markers. CONCLUSION: This retrospective investigation demonstrated that TS, Ki-67, and p53 staining each had significant prognostic value for patients with Dukes' B and C colon carcinoma. However, none of the markers could be used to clearly discern groups of individuals who would be predicted to derive greater or lesser benefit from the use of adjuvant chemotherapy.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias do Colo/química , Antígeno Ki-67/análise , Timidilato Sintase/análise , Proteína Supressora de Tumor p53/análise , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Colectomia , Neoplasias do Colo/mortalidade , Neoplasias do Colo/terapia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Técnicas Imunoenzimáticas , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
7.
Clin Cancer Res ; 8(12): 3857-62, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12473600

RESUMO

PURPOSE AND EXPERIMENTAL DESIGN: The purpose is to define intratumoral microvessel density (MVD) and potential biological markers that correlate with inflammatory breast cancer (IBC), we examined MVD, estrogen receptor a (ER) status, MIB-1 proliferation index, p53, and c-erbB-2 by immunohistochemistry in archival specimens from 67 women diagnosed with breast cancer with or without the inflammatory phenotype at the Institut Salah Azaiz (Tunis, Tunisia). RESULTS: The moderate (25-50/x400 field) to high microvessel count (>50/x400 field) was observed in 23 (51%) of 45 IBC tumors compared with 3 (14%) of 22 non-IBC tumors (P = 0.0031; chi(2) test). The presence of ER was found in 6 (14%) of 44 cases versus 7 (32%) of 22 cases in IBC and non-IBC, respectively (P = 0.10). In this series of 67 patient tumors, the median MVD count in ER-negative breast tumors was 21, whereas the median count was 4 in ER-positive breast tumors (P = 0.08; Wilcoxon rank-sum test). However, MIB-1, p53, and c-erbB-2 were not significantly different between IBC and non-IBC tumors. The intratumoral MVD between IBC and non-IBC was still statistically significant after adjustment for multiple comparisons (P = 0.02; Bonferroni test). CONCLUSIONS: These data suggest that there is an increased MVD in breast cancer with the inflammatory phenotype as compared with breast cancer without the inflammatory phenotype.


Assuntos
Adenocarcinoma/irrigação sanguínea , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/irrigação sanguínea , Proteínas de Neoplasias/metabolismo , Neovascularização Patológica/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio , Feminino , Humanos , Técnicas Imunoenzimáticas , Antígeno Ki-67/metabolismo , Sistema Linfático/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo
8.
J Clin Oncol ; 20(7): 1735-43, 2002 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11919229

RESUMO

PURPOSE: To evaluate the value of thymidylate synthase (TS), Ki-67, and p53 as prognostic markers in patients with Dukes' B2 and C colon carcinoma. METHODS: We conducted a retrospective analysis to evaluate the prognostic value of TS, Ki-67, and p53 in 465 patients with Dukes' B2 (220 patients) or Dukes' C (245 patients) colon carcinoma. Patients represent a nonrandom subset obtained from five randomized phase III trials and were treated with either surgery alone (151 patients) or surgery plus fluorouracil-based chemotherapy (314 patients). All three markers were assayed using immunohistochemical techniques. RESULTS: With a minimum follow-up of 5 years, our retrospective analysis failed to demonstrate a consistent and significant association between TS, Ki-67, or p53 and either disease-free survival or overall survival. Exploratory analyses did not reveal a convincing explanation for these results that are in conflict with the published literature. Notable interactions were observed. In particular, high Ki-67 levels were associated with increased (decreased) survival in patients with low (high) TS intensity. Patients whose tumors stained positively for p53 seemed to benefit substantially from the use of adjuvant chemotherapy compared with those who were not treated (P =.05). CONCLUSION: This retrospective investigation failed to demonstrate a significant association between TS, Ki-67, or p53 staining and clinical outcome.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias do Colo/química , Antígeno Ki-67/análise , Timidilato Sintase/análise , Proteína Supressora de Tumor p53/análise , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Colectomia , Neoplasias do Colo/enzimologia , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida
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