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1.
Phytomedicine ; 12(8): 549-54, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16121514

RESUMO

OBJECTIVE: To evaluate the effects of Hochuekkito, a traditional Japanese and Chinese medicine, in the treatment of elderly patients with general weakness. To devise a suitable study design for assessing the clinical effectiveness of traditional herbal medicines. METHODS: Fifteen elderly patients (mean +/- SD: age 78.4 +/- 7.8; m/f 3/12) participated in this study. A multicenter, prospective, randomized, double-blind, placebo-controlled study with N of one and responder restricted design was performed. After the run-in period, the patients were divided into responders and non-responders. Only responders were entered in the study, and were randomized into three groups: an active-placebo group, a placebo-active group and an active-active group. The study consisted of two 6-week terms with a 2-week washout period in between. We assessed the Short Form 36 Health Survey (SF-36) and Profile of Mood States (POMS) as an endpoint of quality of life (QOL). In addition, we assessed the biodefense status by measuring the natural killer cytolytic activity (NK activity), IL-2 producing activity of peripheral lymphocytes, lymphocyte proliferating activity and lymphocyte cell-surface antigens. RESULTS: The physical component summary of the SF-36 analysis significantly improved in the Hochuekkito-treated group. Four components (A-H: anger-hostility, F: fatigue, T-A: tension-anxiety, C: confusion) out of six improved in the Hochuekkito-treated group in the POMS analysis. Lymphocyte proliferating activity improved in the Hochuekkito-treated group but not significantly. Concerning the surface antigens of peripheral lymphocytes, the population of CD3 positive cells and CD3CD4 double positive cells increased in the Hochuekkito-treated group. CONCLUSION: We revealed that Hochuekkito improved the QOL and immunological status of elderly patients with weakness by randomized controlled trial. Our study design might be useful for assessing the efficacy of traditional herbal medicine in the future.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Afeto , Idoso , Antidepressivos/administração & dosagem , Antidepressivos/farmacologia , Transtorno Depressivo/patologia , Método Duplo-Cego , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Feminino , Humanos , Japão , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Linfócitos T/efeitos dos fármacos , Resultado do Tratamento
2.
Phytomedicine ; 11(5): 404-10, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15330495

RESUMO

Keishi-bukuryo-gan (Gui-Zhi-Fu-Ling-Wan) (KBG) is a traditional Chinese/Japanese medical (Kampo) formulation that has been administered to patients with "Oketsu" (blood stagnation) syndrome. In the process of neuronal cell death induced by brain ischemia, excessive generation of nitric oxide (NO) free radicals is implicated in the neurotoxicity. In the present study, we examined the protective effects of KBG and its constituent medicinal plants against NO donors, sodium nitroprusside (SNP) and 2,2'-(hydroxynitrosohydrazino)bis-ethanamine (NOC18)-induced neuronal death in cultured rat cerebellar granule cells (CGCs). MTT assay showed cell viability to be significantly increased by the addition of KBG extract (KBGE) (100 microg/ml), Cinnamomi Cortex extract (CCE) (3, 10 and 30 microg/ml), Paeoniae Radix extract (PRE) (100 microg/ml) and Moutan Cortex extract (MCE) (10 and 30 microg/ml) compared with exposure to SNP (30 microM, 24 h) only. Also, cell viability was significantly increased by the addition of KBGE (100 and 300 microg/ml), CCE (30 and 100 microg/ml), PRE (100 and 300 microg/ml) and MCE (30 and 100 microg/ml) compared with exposure to NOC 18 (100 microM, 48 h) only. Persicae Semen extract and Hoelen extract did not protect against NO donor-induced neuronal death. These results suggest that KBG has protective effect against NO-mediated neuronal death in cultured CGCs and that it is derived from Cinnamomi Cortex, Paeoniae Radix and Moutan Cortex.


Assuntos
Cerebelo/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Fitoterapia , Plantas Medicinais , Substâncias Protetoras/farmacologia , Animais , Isquemia Encefálica/induzido quimicamente , Isquemia Encefálica/prevenção & controle , Sobrevivência Celular/efeitos dos fármacos , Cerebelo/citologia , Cinnamomum , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Nitroprussiato , Compostos Nitrosos , Paeonia , Polyporales , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/uso terapêutico , Prunus , Ratos , Ratos Wistar
3.
Int J Oral Maxillofac Surg ; 31(4): 414-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12361076

RESUMO

The loss of heterozygosity (LOH) in tumour suppressor gene loci such as p53, retinoblastoma (rb) and adenomatous polyposis coli (apc) were analyzed in oral cancer tissues with matched controls by employing polymerase chain reaction based/restriction fragment length polymorphism (PCR-RFLP), variable number of tandem repeats (PCR-VNTR) analysis and microsatellite assay. The PCR-RFLP analysis showed an infrequent LOH in rb (17%), p53 (11%) and apc (10%) loci in these cases. The microsatellite assay also revealed only a low frequency of LOH in the microsatellite markers such as TP53 (25%), D5S505 (10%) and D3S1067 (0%) in the same samples. In contrast to the present study, similar studies from Western countries have reported a high frequency of LOH in p53, rb and apc genes in oral cancer tissues. The present preliminary study indicates that the gene aberration by LOH may be an insignificant mechanism in Indian oral cancers with respect to the tumour suppressor genes examined.


Assuntos
Carcinoma de Células Escamosas/genética , Genes Supressores de Tumor/fisiologia , Perda de Heterozigosidade , Neoplasias Bucais/genética , Adulto , Idoso , Carcinoma de Células Escamosas/epidemiologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genes APC/fisiologia , Genes do Retinoblastoma/genética , Genes p53/genética , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Epidemiologia Molecular , Neoplasias Bucais/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
4.
J Exp Clin Cancer Res ; 21(3): 377-82, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12385581

RESUMO

Acetylation of core histones is closely linked to transcriptional activation of various genes. The acetylation levels of nucleosomal histones can be modified through a balance of histone acetyltransferases and deacetylases. To elucidate the role of histone acetylation in human gastric carcinogenesis, we studied the status of histone H4 acetylation in gastric carcinoma tissues and corresponding non-neoplastic mucosa. The status of histone acetylation was assessed by examining the expression of acetylated histone H4 through Western blotting and immunohistochemistry using an anti-acetylated histone H4 antibody. The levels of acetylated histone H4 expression were obviously reduced in 72% (13/18) of gastric carcinomas in comparison with non-neoplastic mucosa by Western blotting. In immunohistochemistry, acetylated histone H4 was clearly detected in the nuclei of both non-neoplastic epithelial and stromal cells, whereas the levels of acetylated histone H4 were heterogeneous or reduced in 66% (38/57) of gastric carcinomas and 46% (6/13) of gastric adenomas. Reduced expression of acetylated histone H4 was also observed in some areas of intestinal metaplasia adjacent to carcinomas. Reduction in the expression of acetylated histone H4 was significantly correlated with advanced stage, depth of tumor invasion and lymph node metastasis. These results suggest that low levels of histone acetylation may be closely associated with the development and progression of gastric carcinomas, possibly through alteration of gene expression.


Assuntos
Adenocarcinoma/metabolismo , Adenoma/metabolismo , Histonas/metabolismo , Neoplasias Gástricas/metabolismo , Acetilação , Adenocarcinoma/patologia , Adenoma/patologia , Western Blotting , Células Epiteliais/patologia , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Técnicas Imunoenzimáticas , Mucosa Intestinal/patologia , Metástase Linfática , Invasividade Neoplásica , Neoplasias Gástricas/patologia , Células Estromais/patologia
5.
Oncogene ; 20(55): 7987-91, 2001 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-11753681

RESUMO

Neoplastic progression in Barrett's esophagus is a multi-step process in which the metaplastic columnar epithelium sequentially evolves through a metaplasia-dysplasia-carcinoma sequence. The expression and DNA copy number of key cell cycle regulatory genes in paired normal and Barrett's esophagus samples was evaluated. Protein levels were evaluated in 60 formalin-fixed, paraffin-embedded human tissues by immunohistochemistry. DNA copy number from 20 fresh tissue pairs was analysed by Southern blot analysis. All normal mucosal samples expressed the p27(kip1) protein, but did not display appreciable nuclear staining for p16(kip4), p21(cip1) or cyclins D1 and E. Barrett's metaplastic specimens displayed increased expression levels of p16(kip4) (74%), p21(cip1) (89%) and cyclins D1 (43%) and E (37%). p27 protein was absent in three cases. There was a significant correlation between the expression of p16(kip4) and cyclin E, and p21(cip1) and p27(kip4) with cyclin D1. DNA analysis did not reveal any amplification or deletion of these genes. Acid suppression, however, was associated with significantly lower expression levels of key cell cycle proteins. Increased expression of key cell cycle regulatory genes appears to occur early in the neoplastic progression associated with Barrett's esophagus. Treatment with proton pump inhibitors appears to alter this increased expression.


Assuntos
Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Ciclo Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores da Bomba de Prótons , Adulto , Idoso , Idoso de 80 Anos ou mais , Antiulcerosos/farmacologia , Esôfago de Barrett/tratamento farmacológico , Ciclina D1/genética , Ciclina E/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Inibidores Enzimáticos/uso terapêutico , Feminino , Dosagem de Genes , Genes Supressores de Tumor , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Antígeno Nuclear de Célula em Proliferação/genética , Bombas de Próton/metabolismo
6.
Clin Cancer Res ; 7(12): 4067-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11751503

RESUMO

CD44 variant exon (CD44v) 3 is a heparan sulfate-binding isoform of CD44. The role of CD44v3 in invasion and metastasis associated with heparan sulfate in colon cancer cell lines and cases of colon cancer was examined. Expression of CD44v3 mRNA and protein was observed in five of six human colorectal cancer cell lines. Colo320 and WiDr cells expressed CD44v3 at high levels. Heparan sulfate treatment increased the invasive activity of Colo320 and WiDr cells to rates 14.3 and 12.6 times higher, respectively, than that of untreated cells. However, heparan sulfate treatment did not affect cell growth. Repression of CD44v3 protein production by antisense S-oligodeoxynucleotide treatment reduced the binding affinities and capacities for heparan sulfate by Colo320 and WiDr cells in comparison with that of control cells, and it also reduced the invasiveness of both cell lines to one-fifth that of control cells. In heparan sulfate-treated Colo320 cells, the levels of CD44v3 protein in the Triton X-100-insoluble fraction and moesin-precipitated fraction were increased, suggesting that heparan sulfate treatment facilitates association of CD44 molecules with the cytoskeleton. Immunohistochemical analysis showed CD44v3 to be expressed in 21 of 37 (57%) colorectal cancer cases. Positive CD44v3 expression was associated with more advanced pathological stage and poorer prognosis than negative CD44v3 expression. These data support a role for CD44v3 in invasion and metastasis by colorectal carcinoma cells.


Assuntos
Antígenos CD/genética , Neoplasias do Colo/patologia , Éxons , Variação Genética , Heparitina Sulfato/farmacologia , Receptores de Hialuronatos/genética , Sequência de Bases , Divisão Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Neoplasias do Colo/cirurgia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Citoesqueleto/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Heparitina Sulfato/farmacocinética , Humanos , Cinética , Invasividade Neoplásica , Oligodesoxirribonucleotídeos Antissenso/genética , Isoformas de Proteínas/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Tionucleotídeos , Fatores de Tempo , Células Tumorais Cultivadas
7.
Differentiation ; 68(1): 13-21, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11683489

RESUMO

Inactivation of nuclear retinoic acid receptor beta (RARbeta) expression is implicated in tumorigenesis. We hypothesized that loss of RARbeta in gastric cancer cells may occur as a result of multiple factors, including epigenetic modifications which alter RARbeta promoter chromatin structure. We examined hypermethylation of CpG islands present in the RARbeta promoter by methylation-specific PCR and the expression of RARbeta in gastric cancer cell lines and tissues. Three (MKN-28, -45 and -74) out of eight gastric cancer cell lines had a loss of RAR expression associated with promoter methylation. RARbeta expression was retrieved in these cell lines by treatment with 5-azacytidine or by the histone deacetylase inhibitor trichostatin A. Promoter hypermethylation was detected in 64% (7/11) of gastric carcinoma tissues with reduced expression of RARbeta, whereas it was detected in 22% (2/9) of tumors with retained RARbeta expression. To investigate the functions of exogenous RARbeta in gastric cancer cells, we transfected a retroviral RARbeta expression vector (LNSbeta) into MKN-28 cells that have hypermethylation of the RARbeta promoter. Overexpression of RAR in MKN-28 cells appeared to regulate the expression of DNA methyltransferase and DNA demethylase and the acetylation of hitone H4. These results suggest that the transcriptional inactivation of the RARbeta by promoter CpG hypermethylation is frequently associated with gastric carcinoma. Our data also suggests that DNA methylation plays a pivotal role in establishing and maintaining an inactive state of RARbeta by rendering the chromatin structure inaccessible to the transcription machinery.


Assuntos
Ilhas de CpG , Metilação de DNA , Receptores do Ácido Retinoico/genética , Neoplasias Gástricas/genética , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Proteína de Ligação a CREB , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Transativadores/metabolismo , Transfecção , Células Tumorais Cultivadas
8.
Prostate ; 49(1): 19-29, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11550207

RESUMO

BACKGROUND: We determined whether treatment of metastatic prostate cancer cells with doxorubicin (DOX) and interferon-alpha (IFN-alpha) prevented the emergence of highly undifferentiated tumor cells. METHODS: The state of cell differentiation was determined by analysis of prostate-specific antigen (PSA), E-cadherin, keratin, and vimentin. RESULTS: Human prostate cancer LNCaP-LN3 cells growing in culture as multicell spheroids expressed higher levels of E-cadherin and E-cadherin-associated beta-catenin than LNCaP-LN3 cells growing as monolayers. Treatment of cells with DOX downregulated PSA, E-cadherin, and keratin, and upregulated expression of vimentin and vascular endothelial growth factor (VEGF) mRNA. While treatment of cells with IFN-alpha did not alter gene expression, the addition of IFN-alpha to cultures treated with DOX produced synergistic toxicity and abrogated the changes in gene expression observed in cells treated with DOX alone. CONCLUSIONS: Treatment with IFN-alpha and DOX should be further explored as a therapeutic strategy for androgen-insensitive prostate cancer.


Assuntos
Antineoplásicos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Transformação Celular Neoplásica , Doxorrubicina/farmacologia , Interferon-alfa/farmacologia , Neoplasias da Próstata/patologia , Androgênios/farmacologia , Caderinas/análise , Caderinas/biossíntese , Interações Medicamentosas , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Humanos , Queratinas/análise , Queratinas/biossíntese , Masculino , Antígeno Prostático Específico/análise , Antígeno Prostático Específico/biossíntese , Células Tumorais Cultivadas , Regulação para Cima , Vimentina/análise , Vimentina/biossíntese
9.
Int J Oncol ; 19(3): 507-12, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11494028

RESUMO

Telomeric repeat binding factor 1 (TRF1) and 2 (TRF2) may play key roles in the maintenance of telomere function. TRF1 negatively regulates telomere elongation, while TRF2 protects the chromosome ends by inhibiting end-to-end fusions. We examined the expression of TRF1 and TRF2 in 20 gastric carcinomas by reverse transcription polymerase chain reaction and then analyzed the relation with telomerase activity and other telomerase components such as human telomerase reverse transcriptase (TERT), human telomerase RNA component (hTR), human telomerase-associated protein (TEP1) and TRF1-interacting, ankyrin-related ADP-ribose polymerase (tankyrase) as well as TRF1-interacting nuclear protein 2 (TIN2). Of 20 gastric carcinomas examined, 10 (50%) and 12 (60%) expressed TRF1 and TRF2 at higher levels than did non-neoplastic mucosa, respectively. No obvious correlation was observed between TRF1 expression and telomerase activity or expression of TERT, hTR and TEP1. Carcinomas with high TRF1 expression expressed significantly higher levels of tankyrase and TIN2 than did those with low TRF2 expression (p<0.05). The telomerase activities and the levels of TERT, hTR and TEP1 showed tendency to be lower in tumors expressing TRF1 at low levels, although it was not significant. On the other hand, carcinomas with short telomere length (shorter than 2 Kbp) expressed significantly stronger telomerase activities and higher TRF1 expression (p<0.05) and tended to express TRF2 and TIN2 at higher levels than those with long telomere length. The results suggest that gastric carcinomas with short telomeres need high levels of telomerase activity and large quantity of TRFs and TIN2, whereas those with long telomeres do not require high levels of telomerase activity and telomere associated proteins.


Assuntos
Proteínas de Ligação a DNA/genética , Neoplasias Gástricas/genética , Tanquirases , Proteínas de Ligação a Telômeros , Telômero/genética , Idoso , Idoso de 80 Anos ou mais , Primers do DNA/química , Proteínas de Ligação a DNA/metabolismo , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Telomerase/genética , Telomerase/metabolismo , Telômero/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas , Proteína 2 de Ligação a Repetições Teloméricas
10.
J Pathol ; 194(3): 341-8, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11439367

RESUMO

Loss of PTEN (phosphatase and tensin homologue deleted from chromosome 10) function has been implicated in the progression of several types of cancer. Allele loss close to the PTEN locus occurs in sporadic colon cancer and germline PTEN mutations cause Cowden disease, an inherited cancer syndrome characterized by an increased incidence of gastrointestinal tract lesions that can progress to colorectal carcinoma. However, although PTEN is a good candidate for involvement in the pathogenesis of sporadic colon cancer, previous analyses have not revealed a high frequency of somatic mutations in colorectal tumours. Alternative mechanisms which could lead to a loss of PTEN expression in colon cancer have not been investigated. This study monitored PTEN mRNA and protein levels in a panel of 50 tumour tissues obtained from 35 patients with sporadic colon cancer. RT-PCR and immunohistochemistry were used to evaluate the expression of mRNA and protein, respectively, in normal, adenoma and adenocarcinoma colorectal tissues as well as in metastatic lesions. To overcome the problem of heterogeneity and normal stromal cell contamination in homogenized tissue specimens, specific cell types were isolated by microdissection prior to PCR analysis. No loss of PTEN expression was evident in any of the colon tissues examined. PTEN protein was localized exclusively in the cytoplasm of normal and tumour cells and no correlation of immunostaining intensity and tumour stage or grade was revealed. As with previous deletion and mutation analyses, the present study suggests that loss of PTEN expression is not prevalent in sporadic colon cancer.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/secundário , Neoplasias Colorretais/genética , Neoplasias Colorretais/secundário , Monoéster Fosfórico Hidrolases/genética , RNA Mensageiro/análise , Proteínas Supressoras de Tumor , Adenoma/genética , Animais , Western Blotting/métodos , Deleção de Genes , Humanos , Imuno-Histoquímica/métodos , Camundongos , Camundongos Nus , Transplante de Neoplasias , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Oncol Rep ; 8(4): 791-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11410785

RESUMO

Chromosomal instability in colorectal cancers is associated with functional loss of a mitotic check point partly due to mutations of the Bub1, one of the mitotic check point genes. However, mutation of coding sequences of human Bub1 gene has not been fully elucidated in gastric carcinomas. We performed sequencing analysis on reverse transcriptase-polymerase chain reaction (RT-PCR) product of the Bub1 cDNA (entire coding sequence) from 5 human gastric carcinomas as well as on genomic PCR products of Bub1 kinase domain from 7 gastric carcinoma tissues. Although sequencing analysis of the Bub1 cDNA revealed several point mutations in 2 gastric carcinoma cases, we could not confirm the mutations by analyzing genomic DNA. Furthermore, genomic DNA sequencing revealed no mutations in the kinase domain of the Bub1 gene in any gastric carcinoma examined. These results suggest that mutational inactivation of the Bub1 gene might not play a key role in human stomach carcinogenesis.


Assuntos
Adenocarcinoma Mucinoso/genética , Adenocarcinoma/genética , Mutação , Proteínas Quinases/genética , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Adenocarcinoma Mucinoso/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ciclo Celular/genética , Análise Mutacional de DNA , Primers do DNA/química , DNA de Neoplasias/análise , DNA de Neoplasias/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Proteínas Serina-Treonina Quinases , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/patologia
15.
Int Rev Cytol ; 204: 49-95, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11243597

RESUMO

Genetic and epigenetic alterations of multiple cancer-related genes and molecules are implicated in the development and progression of human gastric carcinomas. Reactivation of telomerase, inactivation of p53 tumor suppressor gene, overexpression of cyclin E, and reduced expression of p27 KIP1 by disorganized degradation in proteasome are common events of both well-differentiated and poorly differentiated gastric adenocarcinomas. Inactivation of hMLH1 mismatch repair gene by CpG hypermethylation resulting in microsatellite instability, amplification of c-erbB2 oncogene, inactivation of APC tumor suppressor gene, and K-ras mutations are preferentially associated with well-differentiated gastric cancer. Conversely, reduction or loss of E-cadherin and catenins by both mutation and CpG hypermethylation and K-sam and c-met oncogene amplification are necessary for the development and progression of poorly differentiated or scirrhous gastric carcinomas. Interaction between cancer cells expressing c-met and hepatocyte growth factor from stromal cells is implicated in morphogenesis of gastric cancer.


Assuntos
Neoplasias Gástricas/genética , Animais , Substâncias de Crescimento , Humanos , Metástase Neoplásica/genética , Neoplasias Gástricas/patologia , Telomerase , Telômero
16.
Jpn J Cancer Res ; 92(1): 42-50, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11173543

RESUMO

Expression of retinoic acid receptor beta (RARbeta) is reported to be absent or down-regulated in oral squamous cell carcinomas. Recently, we found that the growth-inhibitory effect of 9-cis-retinoic acid (9CRA) on oral squamous cell carcinoma may depend on the expression levels of endogenous RARbeta. In order to clarify the role of RARbeta in growth and differentiation, we transfected RARbeta expression vector into oral squamous carcinoma cell lines, HSC-4 and Ho-1-N-1. Both RARbeta-transfected cell lines displayed growth inhibition. Moreover, RARbeta-transfected clones underwent morphological changes, and RARbeta-transfected HSC-4 clones underwent apoptosis even in the absence of 9CRA treatment. In contrast, RARbeta-transfected Ho-1-N-1 clones exhibited cell cycle arrest without undergoing apoptosis initially; however, apoptosis was induced in these cells after 6 days of 9CRA treatment. RARalpha and RARgamma expression was reduced at both the protein and mRNA levels in RARbeta transfectants, whereas the expression of retinoid X receptor alpha (RXRalpha) was not altered. RARb transfectants exhibited alterations in the levels of cell cycle-associated proteins, histone acetyltransferase (HAT) and apoptosis-associated proteins. After 6 days of 9CRA treatment, RARbeta transfectants overexpressed Waf1 / Cip1 / Sdi1 / p21, Kip1 / p27, chk1, p300 / CBP, BAX, Bak, Apaf 1, caspase 3 and caspase 9. Conversely, E2F1, cdc25B and HDAC1 were down-regulated in these transfectants. In addition, histone H4 acetylation was induced in RARb transfectants. These findings suggest that histone acetylation mediated by histone acetyltransferase and p300 / CBP may play a role in the growth arrest and apoptosis induced by RARbeta transfection in oral squamous cell carcinoma.


Assuntos
Antineoplásicos/farmacologia , Apoptose/fisiologia , Carcinoma de Células Escamosas/metabolismo , Ciclo Celular/efeitos dos fármacos , Neoplasias Bucais/metabolismo , Receptores do Ácido Retinoico/metabolismo , Tretinoína/farmacologia , Alitretinoína , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/fisiopatologia , Divisão Celular/efeitos dos fármacos , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/fisiopatologia , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/genética , Receptor alfa de Ácido Retinoico , Transfecção , Células Tumorais Cultivadas/efeitos dos fármacos
17.
Gastric Cancer ; 4(3): 113-21, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11760076

RESUMO

Although histopathological diagnosis is extremely useful for the definitive as well as the supportive diagnosis of gastric cancer in clinical practice, it is limited in certain respects. Over the past 15 years, integrated research in molecular pathology has clarified the details of genetic and epigenetic abnormalities of cancer-related genes in the course of the development and progression of gastric cancer. These abnormalities, which include telomerase activation, genetic instability, and abnormalities in oncogenes, tumor suppressor genes, cell-cycle regulators, cell adhesion molecules, and DNA repair genes, could be effective markers in the molecular diagnosis of gastric cancer. It is possible that the molecular analysis of these alterations in histopathology specimens may overcome deficiencies in diagnoses that depend only on histomorphology, and, consequently, we may be able to improve the differential diagnosis of cancer, obtain information on the grade of malignancy, and identify patients at high risk of developing multiple primary cancers. In Hiroshima, we have established a system of molecular-pathological diagnosis as a routine service; about 5,000 lesions of the stomach have been subjected to this diagnosis, and much useful information has been obtained. In the near future, genetic analysis by means of DNA microarray may become routine in the diagnosis of gastric cancer. Genetic analysis of histopathology specimens may make clear the characteristics of individual cancers; indicating the common and specific features of molecular pathogenesis that may be directly connected with gene therapy or molecular-targeted therapy. By analyzing the relationship between single-nucleotide polymorphisms and cancer susceptibility, we will be able to obtain information on cancer prevention from histopathology samples.


Assuntos
Adenocarcinoma/genética , Adenoma/genética , DNA de Neoplasias/análise , Neoplasias Gástricas/genética , Adenocarcinoma/patologia , Adenoma/patologia , Previsões , Marcadores Genéticos , Humanos , Japão , Biologia Molecular/métodos , Neoplasias Gástricas/patologia , Fatores de Tempo
18.
Pathobiology ; 69(4): 219-24, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12007281

RESUMO

The MRE11 complex (MRE11, RAD50, NBS1) are required for the repair of DNA double-strand breaks and have another important function in regulating telomere length. The silent information regulator (Sir) proteins required for telomere position effect also bind telomeres. hRap1 protein is a human ortholog of yeast Rap1 which regulates telomere length by interacting with TRF2 and is recruited to telomeres by TRF2. We examined the expression of the MRE11 complex (MRE11, RAD50, NBS1), Sir2 and hRAP1 in 20 gastric carcinomas by reverse transcription polymerase chain reaction and then analyzed the relation between telomerase activity and other telomerase components such as human telomerase reverse transcriptase (TERT), human telomerase RNA component (hTR), human telomerase-associated protein (TEP1), telomeric repeat binding factor 1 (TRF1), TRF2- and TRF1-interacting, ankyrin-related ADP-ribose polymerase (tankyrase) as well as TRF1-interacting nuclear protein 2 (TIN2). Of twenty gastric carcinomas examined, 13 (65%), 14 (70%), 16 (80%), 12 (60%) and 13 (65%) expressed MRE11, RAD50, NBS1, Sir2 and hRap1 at higher levels than corresponding nonneoplastic gastric mucosa, respectively. No obvious correlation was observed between MRE11 complex expression and telomerase activity or expression of TERT, hTR, TEP1, tankyrase and TIN2. Carcinomas with high TRF1 expression expressed significantly higher levels of MRE11 and RAD50 than those with low TRF1 expression (p < 0.05). On the other hand, carcinomas with high TRF2 expression expressed significantly higher levels of MRE11, NBS1 and hRap1 than those with low TRF2 expression (p < 0.05). These results suggest that gastric carcinomas with high TRF1 and TRF2 expression may need a large quantity of the MRE11 complex. Moreover, gastric carcinomas with high TRF1 expression may require a large quantity of hRap1.


Assuntos
Carcinoma/enzimologia , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Endodesoxirribonucleases/metabolismo , Proteínas Nucleares , Proteínas de Saccharomyces cerevisiae , Neoplasias Gástricas/enzimologia , Proteínas de Ligação a Telômeros , Telômero , Idoso , Idoso de 80 Anos ou mais , Carcinoma/genética , Carcinoma/patologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/genética , Endodesoxirribonucleases/genética , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Feminino , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Complexo Shelterina , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Telomerase/metabolismo , Proteína 1 de Ligação a Repetições Teloméricas
19.
Am J Pathol ; 157(5): 1523-35, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11073812

RESUMO

We determined whether hyperplastic mucosa adjacent to colon cancer contributes to neoplastic angiogenesis. Surgical specimens of human colon cancer (40 Dukes' stage B and 34 Dukes' stage C) were analyzed by immunohistochemistry for expression of proliferative and angiogenic molecules. The mucosa adjacent to Dukes' stage C tumors (but not Dukes' stage B tumors) had a higher Ki-67 labeling index and a higher expression of epidermal growth factor receptor and transforming growth factor-alpha than distant mucosa. The expression levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8, and the vascular density in the adjacent mucosa were similar to those in the tumor lesions and significantly higher than those in the distant mucosa. The expression of interferon-beta inversely correlated with the level of pro-angiogenic molecules and the vascular density. The injection of metastatic human colon cancer cells and murine colon cancer cells into the cecal wall of mice induced hyperplastic changes in the adjacent mucosa which expressed higher levels of epidermal growth factor receptor, basic fibroblast growth factor, and vascular endothelial growth factor, and lower levels of interferon-beta than did the control mucosa, which directly correlated with the degree of hyperplasia. These data suggest that metastatic human colon cancer cells can induce hyperplasia in the adjacent mucosa, which in turn produces angiogenic molecules that contribute to neoplastic angiogenesis.


Assuntos
Colo/irrigação sanguínea , Colo/patologia , Neoplasias do Colo/irrigação sanguínea , Mucosa Intestinal/irrigação sanguínea , Mucosa Intestinal/patologia , Neovascularização Patológica/patologia , Animais , Neoplasias do Colo/patologia , Humanos , Hiperplasia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estadiamento de Neoplasias , Transplante de Neoplasias , Neovascularização Patológica/metabolismo , Células Tumorais Cultivadas
20.
Int J Cancer ; 88(6): 992-7, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11093826

RESUMO

The effect of trichostatin A (TSA), histone deacetylase inhibitor, on cell growth and the mechanism of growth modulation was examined in 8 gastric and 3 oral carcinoma cell lines which included 9-cis-retinoic acid resistant (MKN-7 and Ho-1-N-1) and IFN-beta resistant cell lines (MKN-7, -28 and -45). TSA inhibited growth in all cell lines examined. Apoptotic cell death was confirmed by apoptotic ladder formation and induction of a cleaved form (85 kDa) of poly (ADP-ribose) polymerase (PARP) induction. TSA enhanced the protein expression of p21(WAF1), CREB-binding protein, cyclinE, cyclin A, Bak and Bax, while it reduced the expression of E2F-1, E2F-4, HDAC1, p53 and hyperphosphorylated form of Rb. Furthermore, TSA induced morphological changes, such as elongation of cytoplasm and cell-to-cell detachment, in gastric and oral carcinoma cell lines. These results suggest that TSA may inhibit cell growth and induce apoptosis of gastric and oral carcinoma cells through modulation of the expression of cell cycle regulators and apoptosis-regulating proteins.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Ácidos Hidroxâmicos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2 , Apoptose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Divisão Celular/efeitos dos fármacos , Fragmentação do DNA , Resistencia a Medicamentos Antineoplásicos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas de Membrana/metabolismo , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Proteína Killer-Antagonista Homóloga a bcl-2 , Proteína X Associada a bcl-2
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