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1.
Hepatology ; 64(3): 774-84, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27082062

RESUMO

UNLABELLED: Angiogenesis inhibition by the vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) inhibitor sorafenib provides survival benefit in hepatocellular carcinoma (HCC); however, angiogenic escape from sorafenib may occur due to angiogenesis-associated fibroblast growth factor receptor (FGFR) pathway activation. In addition to VEGFR and PDGFR, dovitinib inhibits FGFR. Frontline oral dovitinib (500 mg/day, 5 days on, 2 days off; n = 82) versus sorafenib (400 mg twice daily; n = 83) was evaluated in an open-label, randomized phase 2 study of Asian-Pacific patients with advanced HCC. The primary and key secondary endpoints were overall survival (OS) and time to tumor progression (TTP) as determined by a local investigator, respectively. Patients included in the study were ineligible for surgical and/or locoregional therapies or had disease progression after receiving these therapies. The median OS (95% confidence interval [CI]) was 8.0 (6.6-9.1) months for dovitinib and 8.4 (5.4-11.3) months for sorafenib. The median TTP (95% CI) per investigator assessment was 4.1 (2.8-4.2) months and 4.1 (2.8-4.3) months for dovitinib and sorafenib, respectively. Common any-cause adverse events included diarrhea (62%), decreased appetite (43%), nausea (41%), vomiting (41%), fatigue (35%), rash (34%), and pyrexia (30%) for dovitinib and palmar-plantar erythrodysesthesia syndrome (66%) and decreased appetite (31%) for sorafenib. Subgroup analysis revealed a significantly higher median OS for patients in the dovitinib arm who had baseline plasma soluble VEGFR1 (sVEGFR1) and hepatocyte growth factor (HGF) below median levels versus at or above the median levels (median OS [95% CI]: sVEGFR1, 11.2 [9.0-13.8] and 5.7 [4.3-7.0] months, respectively [P = .0002]; HGF, 11.2 [8.9-13.8] and 5.9 [5.0-7.6] months, respectively [P = 0.0002]). CONCLUSION: Dovitinib was well tolerated, but activity was not greater than sorafenib as a frontline systemic therapy for HCC. Based on these data, no subsequent phase 3 study has been planned. (Hepatology 2016;64:774-784).


Assuntos
Antineoplásicos/uso terapêutico , Benzimidazóis/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Niacinamida/análogos & derivados , Compostos de Fenilureia/uso terapêutico , Quinolonas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Benzimidazóis/efeitos adversos , Benzimidazóis/farmacocinética , Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Ásia Oriental/epidemiologia , Feminino , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Pessoa de Meia-Idade , Niacinamida/efeitos adversos , Niacinamida/farmacocinética , Niacinamida/uso terapêutico , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Quinolonas/efeitos adversos , Quinolonas/farmacocinética , Sorafenibe , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
2.
JCO Precis Oncol ; 7: e2200211, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36603172

RESUMO

PURPOSE: In head and neck squamous cell carcinoma (HNSCC), HRAS mutation is a new actionable oncogene driver. We aimed to evaluate HRAS mutational variants, comutation profile, and survival outcomes of this molecularly defined population. METHODS: We leveraged four deidentified patient data sets with HRAS-mutant HNSCC, MD Anderson Cancer Center, Kura Oncology, Inc trial, Foundation Medicine, and American Association for Cancer Research GENIE v.12. Patient demographic information and clinical courses were extracted, when available, in addition to HRAS mutation type and co-occurring mutations. Survival outcomes were analyzed (Kaplan-Meier method). RESULTS: Two hundred forty-nine patients with HRAS-mutant HNSCC were identified from the four data sets. Median age ranged from 55 to 65 years, with a higher frequency in male patients (64%); the majority of HRAS-mutant HNSCC occurred in human papillomavirus-negative HNSCC. HRAS mutation patterns were similar across data sets; G12S was the most common (29%). Treatment responses to tipifarnib were not codon-specific. Compared with wild-type, significantly co-occurring mutations with HRAS were Casp8 (Fisher's exact test, P < .00013), TERT (P < .0085), and NOTCH1 (P < .00013). Analysis of clinical courses from the MD Anderson Cancer Center and Kura Oncology, Inc data sets demonstrated poor clinical outcomes with a high rate of recurrence following primary definitive treatment (50%-67% relapse < 6 months) and short disease-free survival (4.0 months; 95% CI, 1.0 to 36.0) and overall survival (OS; 15.0 months; 95% CI, 6.0 to 52.0). Use of tipifarnib in this data set demonstrated improved OS (25.5 months; 95% CI, 18.0 to 48.0). CONCLUSION: Oncogenic mutations in HRAS occur in 3%-4% of HNSCC, with G12S being the most frequent. Without targeted therapy, patients with HRAS-mutant HNSCC had poor clinic outcomes; observable trend toward improvement in OS has been noted in cohorts receiving treatments such as tipifarnib. The comutation pattern of HRAS-mutant in HNSCC is distinct, which may provide insight to future therapeutic combination strategies.


Assuntos
Neoplasias de Cabeça e Pescoço , Carcinoma de Células Escamosas de Cabeça e Pescoço , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Mutação , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas p21(ras)/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética
3.
J Clin Oncol ; 39(17): 1856-1864, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-33750196

RESUMO

PURPOSE: Mutations in the HRAS (mHRAS) proto-oncogene occur in 4%-8% of patients with recurrent and/or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). Tipifarnib is a farnesyltransferase inhibitor that disrupts HRAS function. We evaluated the efficacy of tipifarnib in patients with R/M mHRAS HNSCC. METHODS: We enrolled 30 patients with R/M HNSCC in a single-arm, open-label phase II trial of tipifarnib for mHRAS malignancies; one additional patient was treated on an expanded access program. After an ad hoc analysis of the first 16 patients with HNSCC with mHRAS variant allele frequency (VAF) data, enrollment was limited to those with a mHRAS VAF of ≥ 20% (high VAF). The primary end point was objective response rate. Secondary end points included assessing safety and tolerability. Patients received tipifarnib 600 or 900 mg orally twice daily on days 1-7 and 15-21 of 28-day cycles. RESULTS: Of the 22 patients with HNSCC with high VAF, 20 were evaluable for response at the time of data cutoff. Objective response rate for evaluable patients with high-VAF HNSCC was 55% (95% CI, 31.5 to 76.9). Median progression-free survival on tipifarnib was 5.6 months (95% CI, 3.6 to 16.4) versus 3.6 months (95% CI, 1.3 to 5.2) on last prior therapy. Median overall survival was 15.4 months (95% CI, 7.0 to 29.7). The most frequent treatment-emergent adverse events among the 30 patients with HNSCC were anemia (37%) and lymphopenia (13%). CONCLUSION: Tipifarnib demonstrated encouraging efficacy in patients with R/M HNSCC with HRAS mutations for whom limited therapeutic options exist (NCT02383927).


Assuntos
Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Mutação de Sentido Incorreto , Proteínas Proto-Oncogênicas p21(ras)/genética , Quinolonas/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proto-Oncogene Mas , Quinolonas/efeitos adversos , Adulto Jovem
4.
Clin Cancer Res ; 14(22): 7564-8, 2008 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19010875

RESUMO

PURPOSE: Nuclear factor-kappaB (NF-kappaB) is constitutively expressed in many acute myelogenous leukemia (AML) cells and AML stem cells. Ex vivo treatment of AML cells with inhibitors of NF-kappaB results in diminished AML cell survival and enhances the cytotoxic effects of chemotherapeutic agents. The purpose of this study was to determine if standard anti-inflammatory agents modulate AML cell nuclear NF-kappaB when administered in conjunction with induction chemotherapy. EXPERIMENTAL DESIGN: Patients with newly diagnosed AML were treated with dexamethasone, choline magnesium trisalicylate, or both for 24 hours prior to and 24 hours following initiation of standard induction chemotherapy. AML cell nuclear NF-kappaB was measured at baseline, 24, and 48 hours. RESULTS: Choline magnesium trisalicylate +/- dexamethasone decreased nuclear NF-kappaB, whereas dexamethasone alone was associated with an increase in nuclear NF-kappaB in AML cells. CONCLUSIONS: These results show the feasibility of NF-kappaB modulation in conjunction with induction chemotherapy for patients with AML using inexpensive readily available medications. A follow-up study to determine the effects of NF-kappaB modulation on clinical end points is warranted.


Assuntos
Anti-Inflamatórios/administração & dosagem , Colina/análogos & derivados , Dexametasona/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , NF-kappa B/biossíntese , Salicilatos/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Colina/administração & dosagem , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , NF-kappa B/efeitos dos fármacos
5.
Leuk Res ; 32(12): 1842-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18614230

RESUMO

Allogeneic hematopoietic stem cell transplantation provides curative therapy for some patients with advanced hematologic malignancies. Disease response after allogeneic transplant is, at least in part, mediated by donor immune cells. In this report we describe a cellular therapy using haploidentical peripheral blood stem cells administered after very low dose total body irradiation (TBI) (100cGy). The donor cells were anticipated to be rejected, so no graft-versus-host (GVHD) prophylaxis was used. Patients with persistent disease beyond 8 weeks could be further treated with infusions of irradiated haploidentical donor cells. Of the 10 patients enrolled in the study, durable engraftment of allogeneic cells was seen in one patient. Two patients with resistant relapsed acute myelogenous leukemia (AML) had a disease response. Analysis of T cell reactivity from one patient who achieved a complete response but did not have durable engraftment of donor cells indicated that disease response was associated with the generation of host-derived anti-leukemic cytotoxic CD8+ T cells that reacted with an AML-associated proteinase 3 epitope. Results from this patient suggest that allogeneic therapy induced a host anti-tumor response associated with cytotoxic T cells reactive with a low affinity self-antigen.


Assuntos
Neoplasias Hematológicas/cirurgia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/sangue , Antígenos CD34/sangue , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Complexo CD3/sangue , Linfócitos T CD8-Positivos/imunologia , Transplante de Células , Feminino , Citometria de Fluxo , Neoplasias Hematológicas/imunologia , Humanos , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/cirurgia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/cirurgia , Linfoma não Hodgkin/imunologia , Linfoma não Hodgkin/cirurgia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Doadores de Tecidos , Expansão de Tecido/métodos , Coleta de Tecidos e Órgãos/métodos , Transplante Homólogo
6.
Oncogene ; 21(45): 6877-83, 2002 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-12362270

RESUMO

A wealth of cytogenetic data has demonstrated that numerous somatic genetic changes are involved in the pathogenesis of human lung cancer. Despite the complexity of the genomic changes observed in these neoplasms, recurrent chromosomal patterns have emerged. In this review, we summarize chromosomal alterations identified in small cell and non-small cell lung cancer, using classical and molecular cytogenetic techniques. These analyses have uncovered a set of chromosome regions implicated in lung cancer development and progression. However, many of the target genes remain unknown. Newer technology, such as array-CGH, when combined with cDNA microarrays and tissue microarrays, will facilitate the integration of genomic and gene expression data and pave the way toward a molecular classification of lung carcinomas. The molecular implications of consistent chromosome imbalances found in lung cancer to date are also discussed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma de Células Pequenas/genética , Aberrações Cromossômicas , Neoplasias Pulmonares/genética , Humanos , Cariotipagem , Hibridização de Ácido Nucleico
7.
Int J Oncol ; 26(3): 691-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15703825

RESUMO

The elevated incidence of breast cancer in women has been associated with prolonged exposure to high levels of estrogens. Our laboratory has demonstrated that treatment of the immortalized human breast epithelial cells MCF-10F with 17beta-estradiol (E2) or its metabolites 4-hydroxy-estradiol (4-OH-E2) and 2-hydroxy-estradiol (2-OH-E2) induces phenotypical changes indicative of neoplastic transformation. The MCF-10F cells treated with E2, 2-OH-E2 and 4-OH-E2 form colonies in agar methocel and lost their ductulogenic capacity in collagen matrix, expressing phenotypes similar to those induced by the carcinogen benz(a)pyrene (BP). To investigate whether these phenotypic changes were associated with genomic changes, MCF-10F cells treated with either E2, 2-OH-E2, or 4-OH-E2 at different doses (0.007 nM, 70 nM and 3.6 microM) were analyzed using a combination of standard G-banding and comparative genomic hybridization (CGH). Whereas no aneuploidy was observed in any of the transformed cells, the CGH revealed instead that only cells treated with 4-OH-E2 at the highest concentration (3.6 microM) exhibited DNA gains at 8q24, 9q34 and 20q13 and losses at 13q21.


Assuntos
Aneuploidia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Transformação Celular Neoplásica , Dano ao DNA , Estradiol/farmacologia , Hibridização de Ácido Nucleico , Mama/citologia , Mama/patologia , Relação Dose-Resposta a Droga , Células Epiteliais , Feminino , Humanos , Fenótipo , Células Tumorais Cultivadas
8.
Cancer Genet Cytogenet ; 163(1): 81-5, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16271962

RESUMO

Hybrid tumors of the kidney are not rare. Previous studies of hybrid renal tumors have been valuable for the understanding of the pathogenesis and progression pathways of renal cell neoplasm. In this paper we describe the morphologic, immunohistochemical, and genetic features of 2 oncocytomas with evolving papillary renal cell carcinoma (PRCC) in a nephrectomy specimen of a 60-year old male. The patient was referred for urologic oncology consultation after the incidental discovery of a renal tumor. Nephrectomy was performed and two separate masses were present grossly. The tumors were stained with hematoxylin and eosin, cytokeratin 7 and vimentin. Genetic studies included conventional metaphase cytogenetics and fluorescence in situ hybridization (FISH). Morphologically, both tumors were oncocytomas with numerous microscopic papillary nests and psammoma bodies. Papillary carcinoma nests were highlighted with cytokeratin 7 and vimentin positivity and were more prominent in the larger tumor. Conventional cytogenetics and FISH demonstrated loss of chromosomes Y and 1 and gains of chromosome 7. We postulate that the PRCC represents a neoplastic progression by the gain of chromosome 7 oncocytoma with -Y and -1.


Assuntos
Adenoma Oxífilo/genética , Carcinoma Papilar/genética , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Par 7 , Cromossomos Humanos Y , Neoplasias Renais/genética , Adenoma Oxífilo/patologia , Carcinoma Papilar/patologia , Progressão da Doença , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Neoplasias Renais/patologia , Masculino , Metáfase , Pessoa de Meia-Idade
9.
Clin Cancer Res ; 10(21): 7290-6, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15534104

RESUMO

PURPOSE: Loss of the methylthioadenosine phosphorylase (MTAP) gene at 9p21 is observed frequently in a variety of human cancers. We have shown previously that MTAP can act as a tumor suppressor gene and that its tumor suppressor function is related to its effect on polyamine homeostasis. Ornithine decarboxylase is a key enzyme in the regulation of polyamine metabolism. The aim of this study is to analyze MTAP and ornithine decarboxylase (ODC) expression in primary pancreatic tumor specimens. EXPERIMENTAL DESIGN: We measured MTAP and ODC activity in protein extracts derived from 30 surgically resected tumor samples and eight normal pancreas samples. In a subset of six samples, we also examined MTAP DNA using interphase fluorescence in situ hybridization. In addition, we examined the effect of the ODC inhibitor difluoromethylornithine on two pancreatic adenocarcinoma-derived cell lines. RESULT: MTAP activity was 2.8-fold reduced in adenocarcinomas and 6.3-fold reduced in neuroendocrine tumors compared with control pancreas. Conversely, ODC activity was 3.6-fold elevated in adenocarcinomas and 3.9-fold elevated in neuroendocrine tumors compared with control pancreas. Using interphase fluorescence in situ hybridization, we found in tumor samples that 43 to 75% of the nuclei had lost at least one copy of MTAP locus, indicating that loss of MTAP activity was at least partially because of deletion of the MTAP locus. We also show that inhibition of ODC by difluoromethylornithine caused decreased cell growth and increased apoptosis in two MTAP-deleted pancreatic adenocarcinoma-derived cell lines. CONCLUSIONS: MTAP activity is frequently lost, and ODC activity is frequently elevated in both pancreatic adenocarcinoma and neuroendocrine tumors. Inhibition of ODC activity caused decreased cell growth and increased apoptosis in pancreatic tumor-derived cell lines. These findings suggest that MTAP and polyamine metabolism could be potential therapeutic targets in the treatment of pancreatic cancer.


Assuntos
Tumores Neuroendócrinos/enzimologia , Ornitina Descarboxilase/biossíntese , Ornitina Descarboxilase/fisiologia , Neoplasias Pancreáticas/enzimologia , Purina-Núcleosídeo Fosforilase/genética , Purina-Núcleosídeo Fosforilase/fisiologia , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Apoptose , Western Blotting , Linhagem Celular Tumoral , Cromossomos Humanos Par 9 , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , DNA/metabolismo , Humanos , Hibridização in Situ Fluorescente , Modelos Biológicos , Tumores Neuroendócrinos/metabolismo , Neoplasias Pancreáticas/metabolismo , Poliaminas/química
10.
Cancer Biol Ther ; 14(6): 546-55, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23760497

RESUMO

PDCD2 is an evolutionarily conserved eukaryotic protein with unknown function. The Drosophlia PDCD2 ortholog Zfrp8 has an essential function in fly hematopoiesis. Zfrp8 mutants exhibit marked lymph gland hyperplasia that results from increased proliferation of partially differentiated hemocytes, suggesting Zfrp8 may participate in cell growth. Based on the above observations we have focused on the role of PDCD2 in human cancer cell proliferation and hypothesized that aberrant PDCD2 expression may be characteristic of human malignancies. We report that PDCD2 is highly expressed in human acute leukemia cells as well as in normal hematopoietic progenitors. PDCD2 knockdown in cancer cells impairs their proliferation, but not viability relative to parental cells, supporting the notion that PDCD2 overexpression facilitates cancer cell growth. Prospective analysis of PDCD2 in acute leukemia patients indicates PDCD2 RNA expression correlates with disease status and is a significant predictor of clinical relapse. PDCD2's role in cell proliferation and its high expression in human malignancies make it an attractive, novel potential molecular target for new anti-cancer therapies.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Leucemia Mieloide Aguda/metabolismo , Recidiva Local de Neoplasia/metabolismo , Proteínas Reguladoras de Apoptose/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Expressão Gênica , Técnicas de Silenciamento de Genes , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide Aguda/patologia , Estudos Prospectivos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
Am J Respir Crit Care Med ; 167(7): 976-82, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12411287

RESUMO

Lymphangiomyomatosis (LAM) is characterized by the proliferation of abnormal smooth muscle cells and cystic degeneration of the lung. LAM affects almost exclusively young women. Although lung transplantation provides effective therapy for end-stage LAM, there are reports of LAM recurrence after lung transplantation. Whether these recurrent LAM cells arise from the patient or the lung transplant donor is an area of controversy. We used microsatellite marker fingerprinting and TSC2 gene mutational analysis to study a patient with recurrent LAM after single-lung transplantation. The DNA microsatellite marker pattern indicated the presence of patient-derived LAM cells in the allograft. A somatic one base pair deletion in exon 18 of the TSC2 gene was identified in pulmonary and lymph node LAM cells before transplantation. The same mutation was in the recurrent LAM, demonstrating that the recurrent LAM was derived from the patient. Fluorescence in situ hybridization revealed that cells immunoreactive with the monoclonal antibody HMB-45 did not contain a Y chromosome. These data indicate that histologically benign LAM cells can migrate or metastasize in vivo to the transplanted lung. In addition, the patient had no evidence of a renal angiomyolipoma at autopsy and therefore demonstrated for the first time that somatic TSC2 mutations cause LAM in patients without angiomyolipomas.


Assuntos
Neoplasias Pulmonares/cirurgia , Transplante de Pulmão , Linfangioleiomiomatose/cirurgia , Recidiva Local de Neoplasia/etiologia , Adulto , Alelos , Sequência de Bases , Biomarcadores Tumorais/genética , Biópsia , Cromossomos Humanos Par 16/genética , Cromossomos Humanos Y/genética , DNA de Neoplasias/genética , Éxons/genética , Feminino , Genes Supressores de Tumor , Heterozigoto , Humanos , Perda de Heterozigosidade/genética , Pulmão , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundário , Linfonodos , Linfangioleiomiomatose/genética , Linfangioleiomiomatose/patologia , Repetições de Microssatélites/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/secundário , Complicações Pós-Operatórias/etiologia , Proteínas Repressoras/genética , Falha de Tratamento , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor
13.
Carcinogenesis ; 25(11): 2053-9, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15240509

RESUMO

AKT is frequently activated in various cancers, but its involvement in lung tumor development and progression is not well established. We examined AKT activity by immunohistochemistry in 110 non-small cell lung carcinomas (NSCLCs) using tissue microarrays. AKT activation was observed in 56 (51%) tumors. To further validate activation of the AKT pathway in this series, we examined the phosphorylation status of the mammalian target of rapamycin (mTOR) and forkhead (FKHR), two downstream targets of AKT. Positive staining for phospho-mTOR and phospho-FKHR were detected in 74% and 68% of tumors, respectively, and was significantly associated with activation of AKT. Tumors positive for phosphorylated (active) AKT were present with a similar frequency in low stage (I/II) and high stage (III/IV) tumors, raising the possibility that AKT activation occurs early in tumor progression. We therefore examined AKT activity in 25 bronchial epithelial lesions from 12 patients at high risk of lung cancer. Metaplastic/dysplastic areas showed AKT activity, whereas normal and hyperplastic bronchial epithelia exhibited little or no activity. Since some bronchial epithelial lesions may develop into invasive cancers, we examined the effect of AKT on invasiveness of lung cancer cells, using an in vitro cell invasion assay. Transfection of NSCLC cells with wild-type AKT increased invasiveness in response to hepatocyte growth factor, whereas transfection with dominant negative AKT abrogated this effect. Collectively, these data suggest that AKT activation is a frequent and early event in lung tumorigenesis, which may enhance risk of progression to malignancy. Thus, AKT represents a potentially important target for chemoprevention in individuals at high risk of NSCLC.


Assuntos
Neoplasias Brônquicas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Neoplasias Pulmonares/enzimologia , Lesões Pré-Cancerosas/enzimologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adulto , Idoso , Neoplasias Brônquicas/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Ativação Enzimática , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fosforilação , Lesões Pré-Cancerosas/patologia , Proteínas Quinases/metabolismo , Serina-Treonina Quinases TOR
14.
Mol Carcinog ; 39(4): 234-46, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15057875

RESUMO

Transformation of the human breast epithelial cells (HBEC) MCF-10F with the carcinogen benz(a)pyrene (BP) into BP1-E cells resulted in the loss of the chromosome 17 p13.2 locus (D17S796 marker) and formation of colonies in agar-methocel (colony efficiency (CE)), loss of ductulogenic capacity in collagen matrix, and resistance to anti-Fas monoclonal antibody (Mab)-induced apoptosis. For testing the role of that specific region of chromosome 17 in the expression of transformation phenotypes, we transferred chromosome 17 from mouse fibroblast donors to BP1-E cells. Chromosome 11 was used as negative control. After G418 selection, nine clones each were randomly selected from BP1-E-11neo and BP1-E-17neo hybrids, respectively, and tested for the presence of the donor chromosomes by fluorescent in situ hybridization and polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) analyses. Sensitivity to Fas Mab-induced apoptosis and evaluation of transformation phenotype expression were tested in MCF-10F, BP1-E, and nine BP1-E-11neo and BP1-E-17neo clones each. Six BP1-E-17neo clones exhibited a reversion of transformation phenotypes and a dose dependent sensitivity to Fas Mab-induced apoptosis, behaving similarly to MCF-10F cells. All BP1-E-11neo, and three BP1-E-17neo cell clones, like BP1-E cells, retained a high CE, loss of ductulogenic capacity, and were resistant to all Fas Mab doses tested. Genomic analysis revealed that those six BP1-E-17neo clones that were Fas-sensitive and reverted their transformed phenotypes had retained the 17p13.2 (D17S796 marker) region, whereas it was absent in all resistant clones, indicating that the expression of transformation phenotypes and the sensitivity of the cells to Fas-mediated apoptosis were under the control of genes located in this region.


Assuntos
Apoptose , Mama/citologia , Transformação Celular Neoplásica/genética , Cromossomos Humanos Par 17/genética , Células Epiteliais/citologia , Receptor fas/metabolismo , Animais , Benzo(a)pireno/toxicidade , Mama/enzimologia , Mama/patologia , Divisão Celular/genética , Células Cultivadas , Cromossomos Humanos Par 11/genética , Células Clonais/citologia , Células Clonais/enzimologia , Colágeno/metabolismo , Ensaio de Unidades Formadoras de Colônias , Células Epiteliais/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/enzimologia , Humanos , Células Híbridas/citologia , Hibridização in Situ Fluorescente , Cariotipagem , Camundongos , Repetições de Microssatélites/genética , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Telomerase/metabolismo , Transfecção , Receptor fas/genética , Receptor fas/imunologia
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