RESUMO
BACKGROUND: DNA hypermethylation is a common epigenetic finding in human cancers and is closely associated with transcriptional silencing. In the present study, we investigated the proportion of colorectal neoplasms that showed the adenoma-carcinoma progression and vimentin gene methylation. METHODS: Methylation status of the vimentin gene was examined in nontumoral mucosa, adenomas, and adenocarcinomas from 45 colorectal cancer patients who had adenoma and adenocarcinoma together. Methylation status was determined by bisulfite modification and the methylation-specific polymerase chain reaction. The expression of the vimentin gene product was also examined by immunohistochemistry. RESULTS: Promoter methylation of vimentin was detected in 80% (36 out of 45 cases) of adenocarcinomas, 82.2% (37 of 45) of adenomas, and 28.9% (13 of 45) of normal epithelia, and the difference between neoplastic and normal specimens was statistically significant (p < 0.001). However, no significant correlations were observed between methylation frequency and clinicopathologic variables. Immunohistochemically, vimentin expression was not observed in either normal epithelial cells or tumor cells. Protein expression and vimentin promoter methylation were not associated. CONCLUSIONS: The frequency of aberrant methylation of the vimentin gene was high in colonic adenomas and adenocarcinomas. This result suggests that the methylation status of vimentin may be clinically beneficial in screening for colorectal cancer patients and may be helpful in clarifying colorectal cancer biology.
Assuntos
Humanos , Adenocarcinoma , Adenoma , Biologia , Colo , Neoplasias Colorretais , DNA , Epigenômica , Células Epiteliais , Programas de Rastreamento , Metilação , Mucosa , Reação em Cadeia da Polimerase , Sulfitos , VimentinaRESUMO
BACKGROUND: HPV-other samples are designated as being positive on HPV-PCR, but negative when using specific HPV hybridization probes. We wanted to determine the types on the HPV-other samples by performing sequencing, and to know the pathologic status of the uterine cervix according to the HPV type detected on sequencing. METHODS: For HPV genotying, we used the commercially available HPV DNA Chip test, which contains 15 types of high-risk HPV and 9 types of low-risk HPV. The HPV DNA sequencing was performed for the HPV-other samples of 209 patients who subsequently underwent cervical biopsy. RESULTS: For 204 of the 209 samples, the HPV types detected by sequencing were absent types at used HPV DNA chip. For the remaining 5 samples, sequencing was impossible due to mixed peaks. HPV-81 (19.6%), HPV-61 (18.6%), HPV-62 (16.7%) and HPV-84 (13.9%) were frequently detected. For the HPV-81, -62, -71, and -72 samples, most of the samples displayed normal or LSIL. However, HPV-84 and -61 were more associated with HSIL or worse, as compared to the other types. Conclusion: HPV-81, -61, -62 and -84 were frequently found on sequencing analysis of the HPV-other samples. The pathologic status was diverse, according to the HPV type detected on sequencing.
Assuntos
Feminino , Humanos , Biópsia , Colo do Útero , Quimera , DNA , Análise de Sequência com Séries de Oligonucleotídeos , Papillomaviridae , Análise de Sequência de DNARESUMO
Malignant pleural effusion in multiple myeloma (MM) is extremely rare and is associated with poor prognosis. We experienced two cases of MM IgA type with malignant pleural effusion. The diagnoses were based on characteristic cytology and CD138 immunocytochemistry. The patients received several cycles of combination chemotherapy, since symptoms were more aggressive with an uncontrolled pleural effusion. We review the clinical features of these cases and literature concerning myelomatous pleural effusion.
Assuntos
Humanos , Quimioterapia Combinada , Imunoglobulina A , Imuno-Histoquímica , Mieloma Múltiplo , Derrame Pleural , Derrame Pleural Maligno , PrognósticoRESUMO
BACKGROUND: This study was designed to examine the prevalence of aberrant promoter methylation in a selected panel of genes potentially involved in lymphoid tumors. METHODS: The promoter hypermethylation status of MGMT, DAPK1, hMLH1, CDH1, SHP1, and HIC1 was measured by methylation-specific PCR for 82 cases of B-cell lymphoma. Immunohistochemical staining using MGMT and SHP1 antibodies was conducted on 43 out of 82 cases. RESULTS: The number of MGMT aberrant methylations was lower in diffuse large B-cell lymphoma (DLBCL) than in other malignant lymphomas. The methylation of DAPK1 was frequently detected in follicular lymphoma (FL), marginal zone B-cell lymphoma (MZL) and DLBCL. With one exception, methylation of hMLH1 was not observed in B-cell lymphomas. The methylation frequency of CDH1, and HIC1 was similar in B-cell lymphomas. However, the methylation of SHP1 gene was more frequently observed in cases of FL, DLBCL, and MZL than in chronic lymphocytic lymphoma. MGMT and SHP1 promoter methylation were inversely correlated with the protein expression observed upon immunohistochemical staining. CONCLUSIONS: Aberrant promoter methylation of multiple genes occurs with variable frequency throughout the B-cell lymphomas, and methylation of hMLH1 is rarely observed in B-cell lymphomas.
Assuntos
Anticorpos , Linfócitos B , DNA , Metilação de DNA , Leucemia Linfocítica Crônica de Células B , Linfoma , Linfoma de Células B , Linfoma de Zona Marginal Tipo Células B , Linfoma Folicular , Metilação , Reação em Cadeia da Polimerase , PrevalênciaRESUMO
Splenic metastasis from gynecologic tumors is extremely rare, especially in the absence of apparent disease at other sites. We report two patients that underwent splenectomy for a solitary splenic metastasis from uterine cervical carcinoma. In case 1, a 54-year-old woman with FIGO Stage IIb squamous cell carcinoma of the uterine cervix treated with radiotherapy and chemotherapy developed a solitary splenic metastasis 10 months after initial treatment. In case 2, a 46-year-old woman with FIGO Stage IIb adenocarcinoma of the uterine cervix treated with radiotherapy and chemotherapy was found to have a solitary splenic metastasis 11 months after treatment. Thus all abdominal organs including the spleen must be evaluated for metastases during follow-up of gynecologic tumors.
Assuntos
Feminino , Humanos , Adenocarcinoma , Metástase NeoplásicaRESUMO
BACKGROUND: Angiogenesis, which is essential for tumor growth, is known to occur in the extravascular stroma. However, vascular structures were noted in intravascular tumor emboli in surgical specimens. This prompted our investigation of the frequency and morphology of angiogenesis in tumor emboli. METHODS: Hematoxylin-eosin stained specimens were reviewed for tumor emboli, in 21 cases of stomach adenocarcinoma and 22 cases of colon adenocarcinoma. The cases were examined with immunohistochemistry using antibodies against epithelial antigen (cytokeratin), endothelial antigens (CD31, CD34), lymphatic endothelial antigen (D2-40), and proliferation-associated antigen (MIB1). RESULTS: Endothelial cells were observed in 16 tumor emboli among four (19.1%) of the 21 cases of stomach adenocarcinoma and in 32 tumor emboli among four (18.2%) of the 22 cases of colon adenocarcinoma. The endothelial cells in the tumor emboli showed papillary ingrowth from the vessel wall, formation of vascular lumens, scattered distribution, or surface coating of the emboli. Some of the endothelial cells in the tumor emboli were D2-40-positive, and some were MIB1- positive. CONCLUSIONS: These findings demonstrated that angiogenesis occurs in intravascular tumor emboli as well as in the extravascular stroma. Angiogenesis in the tumor emboli may reflect an active process and may facilitate tumor growth.
Assuntos
Adenocarcinoma , Anticorpos , Colo , Células Endoteliais , Imuno-Histoquímica , EstômagoRESUMO
Claudin-7 has recently been suggested to be a distal nephron marker. We tested the possibility that expression of claudin-7 could be used as a marker of renal tumors originating from the distal nephron. We examined the immunohistochemical expression of claudin-7 and parvalbumin in 239 renal tumors, including 179 clear cell renal cell carcinoma (RCC)s, 29 papillary RCCs, 20 chromophobe RCCs, and 11 renal oncocytomas. In addition, the methylation specific-PCR (MSP) of claudin-7 was performed. Claudin-7 and parvalbumin immunostains were positive in 3.4%, 7.8% of clear cell RCCs, 34.5%, 31.0% of papillary RCCs, 95.0%, 80.0% of chromophobe RCCs, and 72.7%, 81.8% of renal oncocytomas, respectively. The sensitivity and specificity of claudin-7 in diagnosing chromophobe RCC among subtypes of RCC were 95.0% and 92.3%. Those of parvalbumin were 80.0% and 88.9%. The expression pattern of claudin-7 was mostly diffuse in chromophobe RCC and was either focal or diffuse in oncocytoma. All of the cases examined in the MSP revealed the presence of unmethylated promoter of claudin-7 without regard to claudin-7 immunoreactivity. Hypermethylation of the promoter might not be the underlying mechanism for loss of its expression in RCC. Claudin-7 can be used as a useful diagnostic marker in diagnosing chromophobe RCC and oncocytoma.
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Humanos , Biomarcadores Tumorais/metabolismo , Células Tumorais Cultivadas , Distribuição Tecidual , Sensibilidade e Especificidade , Reprodutibilidade dos Testes , Néfrons/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Membrana/análise , Neoplasias Renais/diagnóstico , Carcinoma de Células Renais/diagnóstico , Adenoma Oxífilo/diagnósticoRESUMO
BACKGROUND: Elevated levels of microsatellite alterations at selected tetranucleotide repeat regions (EMAST) have been recently described, and they are a distinct type of microsatellite instability (MSI). We investigated the prevalence of EMAST in squamous cell carcinoma (SCC) of the uterine cervix and we determined the correlation between EMAST and the clinicopathologic parameters, HPV infection and the p53 mutation. METHODS: We examined the 3 mono-, 3 di-, and 5 tetranucleotide repeat markers in 47 cases of SCC, and we performed immunohistochemical staining for p53. HPV detection and genotyping was performed using a commercially available HPV DNA chip. RESULTS: Thirteen out of 47 cases (27.7%) were EMAST(+) with at least one of five tetranucleotide repeat markers. However, MSI at mono- and dinucleo- tide markers was noted in only one case (2.1%). EMAST was not related with stage, size, lymph node metastasis, vascular/lymphatic invasion or the depth of invasion. Positive immunostaining for p53 was significantly more common in EMAST(+) tumors than in the EMAST(-) tumors (p=0.04). HPV-infection was positive in 32 cases. EMAST was not correlated with the state of HPV infection state or the HPV genotype. CONCLUSIONS: 27.7% of the invasive SCCs of the uterine cervix exhibited EMAST, and EMAST in the SCC of the uterine cervix was significantly associated with the p53 mutation.
Assuntos
Feminino , Carcinoma de Células Escamosas , Colo do Útero , Genótipo , Linfonodos , Instabilidade de Microssatélites , Repetições de Microssatélites , Metástase Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , PrevalênciaRESUMO
BACKGROUND: Giant cell tumors (GCT(s)) of bone are benign but can be locally aggressive neoplasms. Their clinical behavior has been difficult to predict on the basis of histology alone. This study investigated the neovascularization and expression of vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase-9 (MMP-9) in GCT(s) of bone; in addition we evaluated their relationship to clinical behavior. METHODS: We evaluated the microvessel number and density in 33 samples of giant cell tumor using CD34 immunohistochemistry. In addition, we examined the immunohistochemical expression of VEGF and MMP-9. RESULTS: The microvessel number alone, not the microvessel density, had statistical association with the clinical stage of GCT(s) (p=0.045). The proportion of cases with strong expression of VEGF increased with advancing clinical stage, however, these results were not statistically significant (p=0.257). The percentage of the cases with strong expression of MMP-9 also increased with advancing clinical stage and this was statistically significant (p=0.022). CONCLUSIONS: These results suggest that intratumor microvessel count and the expression of MMP-9 correlate with GCT stage. Evaluation of their expression may therefore provide prognostic information on the aggressive behavior of GCT(s) of bone.
Assuntos
Tumor de Células Gigantes do Osso , Tumores de Células Gigantes , Células Gigantes , Imuno-Histoquímica , Metaloproteinase 9 da Matriz , Metaloproteinases da Matriz , Microvasos , Prognóstico , Fator A de Crescimento do Endotélio VascularRESUMO
A metastatic carcinoma of the small intestine is rare. Here, the case study of an 80-year-old lung carcinoma patient, with generalized peritonitis due to neoplastic perforation of the small intestine is reported. Pathological studies of a small intestinal mass revealed a metastatic anaplastic carcinoma arising from the lung. Patients with known lung carcinoma, who develop abdominal complaints, should be examined thoroughly. Although it is very difficult to diagnose and treat a metastatic carcinoma of the small intestine, in our judgment, with a greater awareness of this neoplasm, more cases may be diagnosed in the early stages, leading to improved rates of survival.
Assuntos
Idoso de 80 Anos ou mais , Humanos , Carcinoma , Intestino Delgado , Julgamento , Neoplasias Pulmonares , Pulmão , Metástase Neoplásica , PeritoniteRESUMO
BACKGROUND: While neurofibromas have generally been regarded as polyclonal hyperplastic lesions, it remains unclear whether the tumor is a true neoplasm or a hyperplastic lesion. METHODS: Determination of clonality by X chromosome inactivation pattern was investigated in twenty-one cases of neurofibroma employing enzyme digestion and PCR of the HUMARA gene. The histological, immunohistochemical, and ultrastructural characteristics of the tumors were also examined. RESULTS: Immunohistochemically, most of the tumor cells showed vimentin and S-100 protein positivity. Axons were demonstrated by neurofilament protein positivity and were seen mainly at the periphery and rarely in the central portion of the tumor. Ultrastructurally, the tumors were composed of a variety of cell types: perineurial cells, Schwann cells, fibroblasts, and axons. X chromosome inactivation analysis was completed on thirteen out of fifteen cases in which DNA was successfully extracted. Of thirteen neurofibromas that were heterozygous at the HUMARA loci, eleven showed a polyclonal pattern. The remaining two cases were considered as indeterminate for clonality because of unequal band intensity and failure to obtain the normal control DNA. CONCLUSION: The results from this study suggest that neurofibromas are polyclonal in origin and might be a neoplastic lesion comprising non-neoplastic cells among constituent components.
Assuntos
Axônios , Digestão , DNA , Fibroblastos , Imuno-Histoquímica , Neurofibroma , Reação em Cadeia da Polimerase , Proteínas S100 , Células de Schwann , Vimentina , Inativação do Cromossomo XRESUMO
BACKGROUND: Tumors are usually considered to be clonal progeny of single transformed cells. Carcinosarcomas and malignant mixed epithelial tumors are examples where controversies exist regarding the singularity or multiplicity of their cell of origin. METHODS: The authors examined the clonality of carcinosarcomas (7 cases) and malignant mixed epithelial tumor (5 cases) in female patients by X-chromosome inactivation as a marker. Each component of the tumors were picked up by the laser capture microscope. The polymorphic exon 1 CAG trinucleotide repeat in the X-linked human androgen receptor (HUMARA) gene was amplified by a polymerase chain reaction before and after treatment of the methylation-sensitive endonuclease HpaII. RESULTS: Eleven cases were informative for clonality determination. Six out of seven carcinosarcomas and three out of four malignant mixed epithelial tumors revealed the same patterns of X-chromosome inactivation, which suggests that they are monoclonal. In contrast, the patterns of X-chromosome inactivation were different between the two tumor components in each cases of carcinosarcoma and malignant mixed epithelial tumor, indicating that they are of polyclonal origin. CONCLUSIONS: These observations show that although most of carcinosarcomas and malignant mixed epithelial tumors are of monoclonal origin, some of them are of polyclonal origin. This finding suggests that these tumors are genuinely polyclonal, and that they originated in the neoplastic transformation of more than one somatic cells
Assuntos
Feminino , Humanos , Carcinossarcoma , Desoxirribonuclease HpaII , Éxons , Reação em Cadeia da Polimerase , Receptores Androgênicos , Repetições de TrinucleotídeosRESUMO
BACKGROUND: Malignant cell nuclei, in general, have increased amounts of heterochromatin and decreased electron densities of euchromatin, making the chromatin pattern coarser than that of benign cell nuclei. The chromatin pattern in benign and malignant cells, however, is barely explained in terms of molecular structure. In this study, the chromatin pattern of metaplastic and carcinomatous squamous cells of the uterine cervix was correlated with transcriptional activity by ultrastructural autoradiography. METHODS: Punch-biopsied tissues were cultured with 3H-uridine for 5 minutes and processed for electron microscopy. Thin sections of the tissues on nickel grids were covered with photosensitive emulsion and kept cold in a dark room for 10 to 16 weeks. After development and staining, the tissues were observed by electron microscopy. RESULTS: The nuclei of the metaplastic squamous cells consisted mostly of euchromatin. A few silver grains were observed, mainly at the periphery of the nuclei. The nuclei of the carcinomatous cells had increased amounts of heterochromatin along the nuclear membrane, and also in the euchromatin area. Silver grains were observed mainly at the boundary between the heterochromatin and euchromatin. CONCLUSION: These findings suggest that an increased amount of heterochromatin in carcinomatous cells results in an increase of the boundary area between the heterochromatin and euchromatin, an area which may be a transcriptionally active site.
Assuntos
Feminino , Autorradiografia , Domínio Catalítico , Núcleo Celular , Grão Comestível , Colo do Útero , Cromatina , Eucromatina , Heterocromatina , Microscopia Eletrônica , Estrutura Molecular , Níquel , Membrana Nuclear , RNA Mensageiro , PrataRESUMO
PURPOSE: Dysplasia or flat adenoma of the stomach is regarded as a precancerous lesion. However, the frequency and the evolutionary process of malignant transformation of gastric dysplasia are still debated. In order to see whether the lesion was a monoclonal or a polyclonal proliferation, clonality was assayed by X-linked HUMARA polymorphism. MATENRIALS AND METHODS: DNA was extracted from the paraffin-embedded tissue of 16 consecutive cases of endoscopic biopsy, eight of which supplied both dysplastic and nondysplastic tissue for comparison. HUMARA was amplified by PCR with or without pretreatment with methylation- sensitive restriction enzyme, HpaII. The amplification products were electrophoresed on polyacrylamide gel and silver-stained. RESULTS: Among the 16 cases, 13 cases were informative and 3 cases noninformative. Of the 13 cases, one case showed skewed lyonization, rendering 12 cases to be analyzed further. A monoclonal band pattern was noted in 2 cases, and a polyclonal band pattern in 10 cases. A review of the histopathologies of the monoclonal and the polyclonal cases did not reveal features discriminating the two groups. CONCLUSION: These results suggest that gastric dysplasia is a disease entity heterogeneous in the genetic level, and many cases may be non-neoplastic.
Assuntos
Adenoma , Biópsia , DNA , Reação em Cadeia da Polimerase , Estômago , Inativação do Cromossomo XRESUMO
BACKGROUND: Proliferative lesions of the stomach were investigated by in situ hybridization using RNA probes for telomerase components and compared with the results by TRAP (telomeric repeat amplification protocol) assay. METHODS: RNA probes for hTR (human telomerase RNA component) and hTERT (mRNA coding for a catalytic subunit of human telomerase) were made by cloning and in vitro transcription. The probes were applied for in situ hybridization in 23 cases of adenocarcinoma of the intestinal type and adjacent dysplasia, and in the normal and metaplastic mucosa of the stomach. RESULTS: Telomerase activity by TRAP was positive in all cases of adenocarcinoma, most cases of dysplasia, and many cases of normal mucosa. hTR in situ hybridization showed positive staining in the adenocarcinoma cells, dysplastic cells, a few cells in the proliferation zone of the normal mucosa, and a few infiltrated lymphocytes. hTERT showed positive staining in the same cells. CONCLUSIONS: Telomerase is expressed in most cases of dysplastic lesions and is thought to be acquired in the early steps of carcinogenesis. The expression is noted in a few cells of the normal proliferative zones and the infiltrated lymphocytes, emphasizing the importance of in situ detection of telomerase at the cell level.
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Humanos , Adenocarcinoma , Carcinogênese , Domínio Catalítico , Codificação Clínica , Células Clonais , Clonagem de Organismos , Hibridização In Situ , Linfócitos , Mucosa , Reação em Cadeia da Polimerase , Sondas RNA , RNA , RNA Mensageiro , Estômago , TelomeraseRESUMO
Mesoblastic nephroma is a benign neoplasm of the kidney, which is usually diagnosed during the first six months of life. Incidence in adults is exceedingly rare. We report herein a case of mesoblastic nephroma that occurred in the upper pole of the right kidney of a 39-year-old woman. It was a round mass measuring 3X3X2 cm in dimension. Microscopically, it consisted of uniform spindle cells with foci of hyalinization and dystrophic calcification. Tubular structures were entrapped in the tumor. Upon immunohistochemical staining, the spindle cells were found to be positive for smooth muscle actin, desmin, and vimentin. The epithelial cells of the entrapped tubules were positive for cytokeratin. On electron microscopic examination, the spindle cells demonstrated smooth muscle differentiation identified by indented nuclei, microfilaments beneath the cell membrane, dense bodies, and basal lamina-like materials.
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Adulto , Feminino , Humanos , Citoesqueleto de Actina , Actinas , Membrana Celular , Desmina , Células Epiteliais , Hialina , Incidência , Queratinas , Rim , Músculo Liso , Nefroma Mesoblástico , VimentinaRESUMO
We report three autopsy cases of congenital cytomegalovirus (CMV) infection in fetuses with a review of literature. The clinical manifestations in these cases of congenital CMV infection include intrauterine fetal death, hydrops fetalis, and CMV pneumonia associated with cardiovascular defect. The pathological characteristics were as follows: 1) the kidney was the most frequently involved organ, followed by lung and liver, 2) CMV inclusions were found predominantly in epithelial cells and to a lesser degree in endothelial cells, 3) intrahepatic bile duct epithelial cells were frequently involved, and 4) inflammatory reaction around CMV inclusions was not prominent in the early stage of pregnancy. Diagnostic confirmation was obtained by in situ hybridization (ISH) using a biotinylated CMV-DNA probe, which demonstrated intranuclear inclusions and sometimes recognized cells that did not show intranuclear inclusion.
Assuntos
Feminino , Humanos , Masculino , Gravidez , Autopsia , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/congênito , Doenças Fetais , Complicações Infecciosas na GravidezRESUMO
We report three autopsy cases of congenital cytomegalovirus (CMV) infection in fetuses with a review of literature. The clinical manifestations in these cases of congenital CMV infection include intrauterine fetal death, hydrops fetalis, and CMV pneumonia associated with cardiovascular defect. The pathological characteristics were as follows: 1) the kidney was the most frequently involved organ, followed by lung and liver, 2) CMV inclusions were found predominantly in epithelial cells and to a lesser degree in endothelial cells, 3) intrahepatic bile duct epithelial cells were frequently involved, and 4) inflammatory reaction around CMV inclusions was not prominent in the early stage of pregnancy. Diagnostic confirmation was obtained by in situ hybridization (ISH) using a biotinylated CMV-DNA probe, which demonstrated intranuclear inclusions and sometimes recognized cells that did not show intranuclear inclusion.
Assuntos
Feminino , Humanos , Masculino , Gravidez , Autopsia , Infecções por Citomegalovirus/virologia , Infecções por Citomegalovirus/patologia , Infecções por Citomegalovirus/congênito , Doenças Fetais , Complicações Infecciosas na GravidezRESUMO
The purpose of this study is to obtain the clinicopathological characteristics of replication error-positive (RER ) gastric adenocarcinoma in Korean, and to identify the significance of RER in adenoma stage of gastric carcinogenesis. Microsatellite instability was examined at D2S71, D2S119, D3S1067, D6S87, D11S905, DM, AR, VWF, HPRT, and BAT-26 loci. Frameshift mutation of BAX gene was analyzed in RER tumors. Normal and tumor DNA of 76 cases of gastric carcinoma and 25 cases of adenoma were examined. RER was found in 8 of 76 cases (10.5%), and it was more frequently found in adenocarcinoma of female (17.7%) than those of male (4.8%). The frequency of RER was not different between the histologic types, age of the patient, anatomical location of the carcinoma, and the stage. The RER found in adenoma suggests that RER contributes to the malignant transformation early in the adenoma stage of the gastric carcinogenesis. None of the RER tumors revealed frameshift mutation of the BAX gene.
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Feminino , Humanos , Masculino , Adenocarcinoma , Adenoma , Carcinogênese , DNA , Mutação da Fase de Leitura , Hipoxantina Fosforribosiltransferase , Instabilidade de MicrossatélitesRESUMO
BACKGROUND: The coronary stent reduces acute coronary arterial occlusion and late restenosis during and after coronary intervention. However, stent thrombosis and restenosis are still major limitations in widespread use of coronary stent. Local drug delivery with use of heparin-coated stent will be a new approach reducing the incidence of stent thrombosis and restenosis. In order to evaluate the effects of heparin-coated stent on stent restenosis, heparin-coated stents were compared with control stents in a porcine coronary stent restenosis model. METHODS: Stent overdilation injury (stent:artery= 1.3:1.0) was performed with bare Wiktor (Group I, n=10) and heparin-coated Wiktor (Group II, n=20) stents (HEPAMEDTM, Medtronics, U.S.A.) in porcine coronary arteries. Follow-up quantitative coronary angiography (QCA) was performed at 4 weeks after stenting and histopathologic assessments of stented porcine coronary arteries were compared in both groups. RESULTS: 1) On QCA, percent diameter stenosis was significantly higher in Group I than in Group II (16.3+/-6.62% vs. 9.6+/-5.06%, p<0.05). 2) Injury score of stented porcine coronary artery was not different in both groups (1.26+/-0.23 vs. 1.20+/-0.22). 3) Pathologic area stenosis of stented artery was higher in Group I than in Group II (41.6+/-12.5% vs. 27.1+/-9.9%, p<0.005). 4) Neointimal area was higher in Group I than in Group II (4.58+/-1.41 mm2 vs. 2.57+/-1.07 mm2, p<0.05). 5) By immunohistochemistry, proliferating cell nuclear antigen (PCNA) index was higher in Group I compared with in Group II (11.2+/-6.75% vs. 6.3+/-4.14%, p<0.05). CONCLUSIONS: Heparin-coated stent is effective in the prevention of late coronary stent restenosis in a porcine coronary stent restenosis model, which may be related with the inhibition of neointimal cell proliferation.