Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 28
Filtrar
1.
J Gastroenterol Hepatol ; 34(9): 1497-1503, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31062380

RESUMO

BACKGROUND AND AIM: Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. Patients with FAP are screened for germline mutations of two genes, APC and MUTYH. However, limited data exist on the clinical characterization and genotypic spectrum of FAP in China. This study was aimed to determine APC and MUTYH mutational status in a small cohort of FAP probands in China and to characterize the genotype-phenotype correlation in mutated patients. METHODS: Mutation screening of 46 unrelated probands was performed using multigene panels by next-generation sequencing. Clinical data of the index were used to assess genotype-phenotype correlations. RESULTS: Overall, 42 out of 46 (91.30%) unrelated probands found mutations, including 35 (76.09%) with APC mutations, 3 (6.52%) with MUTYH mutations, and 4 (8.70%) with both APC and MUTYH mutations. Ten APC genetic alterations variants were novel. The hereditary pattern of the family with both APC and MUTYH mutations was autosomal dominant inheritance. Upper gastrointestinal polyp was the most common extracolonic manifestations. The onset time for patients with both APC and MUTYH mutations was earlier than MUTYH mutation carriers and similar to APC mutation carriers. But the age of carcinogenesis for patients with both APC and MUTYH mutations was later than APC mutation carriers and similar to MUTYH mutation carriers. CONCLUSION: In this study, we show the importance of using multigene panels that allow for a parallel comprehensive screening. We suggest that genetic testing of patients with suspected adenomatous polyposis syndromes should include APC and MUTYH gene mutation analyses simultaneously.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/genética , DNA Glicosilases/genética , Mutação , Polipose Adenomatosa do Colo/diagnóstico , Polipose Adenomatosa do Colo/etnologia , Povo Asiático/genética , Pequim/epidemiologia , Estudos de Associação Genética , Predisposição Genética para Doença , Hereditariedade , Humanos , Taxa de Mutação , Linhagem , Fenótipo
2.
Chin Med J (Engl) ; 132(4): 379-387, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30707177

RESUMO

BACKGROUND: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. METHODS: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome; recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. RESULTS: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. CONCLUSION: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists. TRIAL REGISTRATION: www.chictr.org.cn (No. ChiCTR-DDD-17013842).


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Radiologistas , Neoplasias Retais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Patologistas , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/mortalidade
3.
Oncologist ; 24(6): 812-819, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30181315

RESUMO

BACKGROUND: IBM Watson for Oncology (WFO), which can use natural language processing to evaluate data in structured and unstructured formats, has begun to be used in China. It provides physicians with evidence-based treatment options and ranks them in three categories for treatment decision support. This study was designed to examine the concordance between the treatment recommendation proposed by WFO and actual clinical decisions by oncologists in our cancer center, which would reflect the differences of cancer treatment between China and the U.S. PATIENTS AND METHODS: Retrospective data from 362 patients with cancer were ingested into WFO from April 2017 to October 2017. WFO recommendations were provided in three categories: recommended, for consideration, and not recommended. Concordance was analyzed by comparing the treatment decisions proposed by WFO with those of the multidisciplinary tumor board. Concordance was achieved when the oncologists' treatment decisions were in the recommended or for consideration categories in WFO. RESULTS: Ovarian cancer showed the highest concordance, which was 96%. Lung cancer and breast cancer obtained a concordance of slightly above 80%. The concordance of rectal cancer was 74%, whereas colon cancer and cervical cancer showed the same concordance of 64%. In particular, the concordance of gastric cancer was very low, only 12%, and 88% of cases were under physicians choice. CONCLUSION: Different cancer types showed different concordances, and only gastric cancers were significantly less likely to be concordant. Incidence and pharmaceuticals may be the major cause of discordance. To be comprehensively and rapidly applied in China, WFO needs to accelerate localization. ClinicalTrials.gov Identifier: NCT03400514. IMPLICATIONS FOR PRACTICE: IBM Watson for Oncology (WFO) has begun to be used in China. In this study, concordance was examined between the treatment recommendation proposed by WFO and clinical decisions for 362 patients in our cancer center, which could reflect the differences of cancer treatment between China and the U.S. Different cancer types showed different concordances, and only gastric cancers were significantly less likely to be concordant. Incidence and pharmaceuticals may be the major causes of discordance. To be comprehensively and rapidly applied in China, WFO needs to accelerate localization. This study may have a significant effect on application of artificial intelligence systems in China.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sistemas de Apoio a Decisões Clínicas , Medicina Baseada em Evidências/métodos , Oncologia/métodos , Neoplasias/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/normas , Inteligência Artificial , China/epidemiologia , Tomada de Decisão Clínica/métodos , Intervalo Livre de Doença , Medicina Baseada em Evidências/normas , Feminino , Humanos , Masculino , Oncologia/normas , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Estudos Retrospectivos
4.
PLoS One ; 12(1): e0169124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28046028

RESUMO

Cancer stem cells (CSCs) are thought to be the "root" of cancer. Although stemness-related factors ALDH1A1 and Sox2 have been used as markers to identify gastric CSCs, the expression pattern and significance of these factors in gastric cancer have not been sufficiently demonstrated. In this study, the expressions of ALDH1A1 and Sox2 were detected by immunohistochemistry in 122 gastric cancer specimens. And the correlation between Sox2 or ALDH1A1 expression and clinicopathological parameters and overall survival data were analyzed. The positive rate of ALDH1A1 expression was 60%, but there was no significant difference between survival rates of ALDH1A1-positive and ALDH1A1-negative patients. Sox2 was expressed in 42% of specimens and was associated with poor prognosis of patients (P = 0.015). Stratified analysis showed that Sox2 expression correlated with shorter lifespan only in patients with cardiac gastric cancers (P = 0.002) or stage I or II gastric cancers (P = 0.002); but not in patients with non-cardiac cancers (P = 0.556) or stage III or IV gastric cancers (P = 0.121). Analysis on a database cohort validated the correlation between Sox2 expression and poor prognosis in stage II cancer. Also, expression of Sox2 was associated with lymphnode metastasis in patients with cardiac gastric cancer (P = 0.037). A multivariate analysis revealed that Sox2 was an independent prognostic factor in cardiac gastric cancer. Our results indicate that predictive value of Sox2 in gastric cancer is associated with cardiac cancer location and with early cancer stages (I and II).


Assuntos
Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição SOXB1/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aldeído Desidrogenase/genética , Família Aldeído Desidrogenase 1 , Estudos de Coortes , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Retinal Desidrogenase , Fatores de Transcrição SOXB1/genética , Neoplasias Gástricas/genética , Resultado do Tratamento
7.
Clin Endosc ; 48(5): 405-10, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26473124

RESUMO

BACKGROUND/AIMS: Early colorectal (CR) neoplasm can be cured by endoscopic submucosal dissection (ESD), but clinical experience and factors associated with complications from ESD for CR neoplasms in China have not been reported. METHODS: Seventy-eight cases of early CR neoplasm treated with endoscopic resection performed between December 2012 and December 2013 at Beijing Military General Hospital were included. Factors associated with ESD complications and procedure times were evaluated. RESULTS: The en bloc resection rate was 88.5% (69/78), tumor size was 32.1±10.7 mm, and procedure time was 71.8±49.5 minutes. The major complication was perforation, which occurred in 8.97% of the ESD procedures. Multivariate logistic regression analysis indicated that only tumor size (p=0.022) was associated with ESD perforation. Tumor size (p<0.001) and the non-lifting sign (p=0.017) were independent factors for procedure time, and procedure time (p=0.016) was a key factor for en bloc resection. After a median 10 months (range, 4 to 16) of follow-up, no patients had local recurrence. CONCLUSIONS: This study indicated that ESD is an applicable method for large early CR neoplasm in the colon and rectum. Tumor size and the non-lifting sign might be considerable factors for increased complication rate and procedural time of ESD.

11.
Shanghai Kou Qiang Yi Xue ; 23(5): 605-8, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25543608

RESUMO

PURPOSE: To investigate the distribution of oral candida species in head and neck cancer (HNC) patients treated with radiation therapy, and provide the basis for planning of clinical preventive measures. METHODS: Saliva was sampled from 60 HNC patients before, during and after radiation. Concomitantly, 60 healthy individuals whose age and sex matched that of the patient group were selected as control group. Oral candida carriages were quantitatively detected and the different candida species were identified by multiple measures such as CHROMagar candida culture medium and API 20C AUX yeast identification system. Then the differences between the two groups in terms of the candida detection rate and the distribution of each species of candida were analyzed with SPSS 17.0 software package. RESULTS: Xerostomia and dysphagia was found in 54 HNC patients during radiotherapy, radiation-induced oral mucotitis(RIOM) was found in 50 HNC patients,and oral candidiasis was found in 18 HNC patients; In radiation group, the detection rate of candida colonization during radiation was 56.7%, 63.3% postradiation, which showed significant differences compared with pre-radiation (X² =18.320,P<0.001 ); Among the 54 identified clinical isolates, candida albicans (n=42) was the most frequent, followed by candida parapsilosis (n=6), candida tropicalis (n=4) and candida glabrata (n=2). In radiation group, the oral candida pathogens detection rate was 30%, and candida colonization was 46.7%. CONCLUSIONS: The oral candida colonization rate was significantly higher in HNC patients after radiotherapy, which indicated that the candida infection may be closely related to RIOM.


Assuntos
Candida , Candidíase Bucal , Neoplasias de Cabeça e Pescoço/radioterapia , Candida albicans , Estudos de Casos e Controles , Humanos , Saliva
13.
J Gastroenterol Hepatol ; 29(4): 757-61, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24325649

RESUMO

BACKGROUND AND AIM: Endoscopic examinations carry a potential risk of cross-infection, and the traditional reprocessing method is time consuming. We evaluated the safety and efficacy of a novel disposable sheathed gastroscope system in clinical practice in comparison with the conventional gastroscope. METHODS: There were two phases in the study. In phase 1, 20 patients with hepatitis B were randomized into two groups: the sheathed group was examined with the novel disposable sheathed gastroscope (n = 10) and the conventional group with the conventional gastroscope (n = 10). Microbiologic tests were performed on each endoscope afterwards. In the second phase, 1120 patients were randomized again into the same two groups with 568 and 552 patients in the sheathed group and the conventional group, respectively. The time duration of the endoscopic procedure and reprocessing were measured. The pathology detection rate of endoscopic examinations, the patients' subjective feelings, and problems occurred during procedures were also recorded. RESULTS: The total instrument turn-around time in the phase 2 sheathed group (9.9 ± 1.3 min) was significantly shorter than the conventional group (39.0 ± 1.4 min, P = 0.000). The mean procedural time was slightly longer in the sheathed group than in the conventional group (4.9 ± 1.4 vs 4.1 ± 1.3 min, P = 0.000). However, the duration of endoscopic reprocessing was much shorter (4.9 ± 0.2 vs 35 ± 0.2 min, P = 0.000). No significant differences were observed in patient discomfort, optical clarity, or pathology detection rate. There were no complications in either group, and no microbial contamination was detected in phase 1 of the study. CONCLUSIONS: Compared with the conventional gastroscope, the novel disposable sheathed gastroendoscope is safe and more efficient in clinical practice.


Assuntos
Infecção Hospitalar/prevenção & controle , Equipamentos Descartáveis , Contaminação de Equipamentos/prevenção & controle , Segurança de Equipamentos , Gastroscópios , Adulto , Carga Bacteriana , China , Desinfecção , Equipamentos Descartáveis/microbiologia , Gastroscópios/microbiologia , Hepatite B/prevenção & controle , Vírus da Hepatite B/isolamento & purificação , Humanos , Controle de Infecções/métodos , Masculino , Risco , Fatores de Tempo
14.
Cell Oncol (Dordr) ; 36(3): 225-31, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23640085

RESUMO

BACKGROUND: Lynch syndrome (or HNPCC) is a colorectal cancer syndrome caused by germline mutations in either one of the DNA mismatch repair (MMR) genes hMLH1, hMSH2, hMSH6 or hPMS2. Mutations in hMLH1 and hMSH2 are most prevalent. Here we aimed to determine the cancer risk of MMR gene mutation carriers and, in addition, the efficacy of colonoscopy surveillance in Chinese Lynch syndrome family members with and without MMR gene mutations. METHODS: A Lynch syndrome family registry encompassing 106 families in Northern China was recently established. Detailed pedigree data for each family were collected and hMLH1 and hMSH2 gene mutation analyses were performed. Germ-line mutations were identified in probands from 42 of these families, and additional genetic analyses were performed in each member of these 42 families to identify mutation and non-mutation carriers. Among the family members included, 180 received colonoscopy and the remaining cases were followed without colonoscopy. RESULTS: Overall 54.8 % of the Lynch syndrome family members carried MMR gene mutations, and these mutation carriers exhibited significantly higher colorectal cancer and other Lynch syndrome-associated cancer risks as compared to non-mutation carriers. The cumulative risk for all Lynch syndrome-related cancers at age 70 was 93.8 % for both hMLH1 and hMSH2 mutation carriers, and 81.7 % and 93.1 % for colorectal cancer at this age, respectively. Whereas 43 of 102 (42.2 %) mutation carriers exhibited significant colonoscopy findings, including 10 colorectal cancers, none of 78 non-mutation carriers exhibited significant findings, and no cancers were detected. In addition, in the mutation carriers, colonoscopy surveillance led to the detection of more early stage cancers than in the non-surveillance group (70.0 % versus 36.5 %, p < 0.01). CONCLUSION: In Lynch syndrome family members, we recommend pre-symptomatic MMR gene mutation analysis in order to identify high risk individuals for colonoscopy surveillance.


Assuntos
Povo Asiático/genética , Colonoscopia , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA/genética , Análise Mutacional de DNA , Mutação/genética , Adulto , Idoso , China/epidemiologia , Família , Feminino , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Fatores de Risco
16.
Electron. j. biotechnol ; 13(5): 6-7, Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591888

RESUMO

Microsatellites, or simple sequence repeats (SSRs), in expressed sequence tags (ESTs) provide an opportunity for low cost SSR development. We looked for EST-SSRs in 403,511 ESTs (generated by 454 sequencing and representing 70,654 contigs and 52,082 singletons) from soybean globular stage embryos. Among 122,736 unique ESTs, 3,729 contained one or more SSRs. In total, 3,989 SSRs were identified including 304 mono, 1,374 di, 2,208 tri, 70 tetra, 13 penta and 20 hexanucleotide SSRs. Thirty three EST-SSRs were selected for primer design and polymorphism analysis using twenty soybean cultivars and one wild-type soybean. Successful amplification was obtained using 21 of these primer pairs, 11 of which detected polymorphisms in these soybean cultivars. These results demonstrated that 454 high throughput sequencing is a powerful tool for molecular marker development. From the 3,989 identified SSRs we expect to obtain a large number of makers with polymorphism among different soybean cultivars, which would be useful for analysis of genetic diversity and maker assisted selection in the soybean breeding programs.


Assuntos
Etiquetas de Sequências Expressas , Glycine max/genética , Genes de Plantas , Marcadores Genéticos , Repetições de Microssatélites , Reação em Cadeia da Polimerase , Polimorfismo Genético , Análise de Sequência de DNA
17.
Zhonghua Yi Xue Za Zhi ; 90(8): 535-9, 2010 Mar 02.
Artigo em Chinês | MEDLINE | ID: mdl-20367965

RESUMO

OBJECTIVE: To investigate the characteristics of APC gene germline mutation in Chinese patients with familial adenomatous polyposis (FAP). METHODS: The genomic DNA was extracted from peripheral venous blood drawn from probands of 14 Chinese FAP families from Beijing, Hebei, Henan, Anhui, Inner Mongolia, Shanxi and Fujian. The APC gene was amplified by PCR and underwent direct sequencing. Large fragment deletion was detected by multiplex ligation-dependent probe amplification (MLPA) only in micromutation-negative samples found by sequencing. RESULTS: APC gene micromutations were found in 9 probands and the micromutation detection rate was 64.3%, including 6 frameshift mutations, 2 splicing mutations and 1 nonsense mutation. Large fragment deletions of APC gene were detected in 2 probands (14.3%). The total mutation detection rate of micromutation and large fragment deletion was 78.6%. Four novel micromutations and 2 novel large fragment deletions were found, including c.2336-2337insT, c.3923-3929delAAGAAAA, c.532-2A > T, c.4179-4180GAdelinsT, large fragment deletions of exons 11 and 10A and large fragment deletion of exon 15 start. CONCLUSIONS: In Chinese FAP patients, the germline mutation type of APC gene is variable; the majority is of frameshift mutation. The most common mutation site is exon 15. The mutation detection rate of APC gene can be boosted effectively by direct sequencing in combination with MLPA.


Assuntos
Polipose Adenomatosa do Colo/genética , Genes APC , Técnicas de Amplificação de Ácido Nucleico/métodos , Adolescente , Adulto , Povo Asiático/genética , Criança , Éxons , Feminino , Deleção de Genes , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Sonda Molecular , Dados de Sequência Molecular , Mutação , Linhagem , Adulto Jovem
18.
World J Gastroenterol ; 16(12): 1522-6, 2010 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-20333795

RESUMO

AIM: To study the characteristics of APC (adenomatous polyposis coli) gene germline mutation in Chinese patients with familial adenomatous polyposis (FAP). METHODS: APC gene from 14 FAP families was amplified by polymerase chain reaction (PCR) and underwent direct sequencing to determine the micromutation type. For the samples without micromutation, the large fragment deletion of APC gene was examined by multiplex ligation-dependent probe amplification (MLPA). RESULTS: There were gene micromutations in 9 families with a micromutation detection rate of 64.3% (9/14), including 6 frameshift mutations (66.7%), 1 nonsense mutation (11.1%) and 2 splicing mutations (22.2%). Large fragment deletions were detected by MLPA in 2 families. The total mutation detection rate of micromutations and large fragment deletions was 78.6% (11/14). CONCLUSION: The detection rate of APC gene germline mutation can be improved by direct sequencing combined with MLPA large fragment deletion detection.


Assuntos
Polipose Adenomatosa do Colo/genética , Genes APC , Mutação , Polipose Adenomatosa do Colo/etnologia , Adolescente , Adulto , Povo Asiático/genética , Criança , China/epidemiologia , Códon sem Sentido , Análise Mutacional de DNA , Éxons , Feminino , Mutação da Fase de Leitura , Deleção de Genes , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fatores de Risco , Adulto Jovem
19.
BMC Plant Biol ; 10: 3, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-20047695

RESUMO

BACKGROUND: MicroRNAs (miRNAs) are a new class of small, endogenous RNAs that play a regulatory role in the cell by negatively affecting gene expression at the post-transcriptional level. miRNAs have been shown to control numerous genes involved in various biological and metabolic processes. There have been extensive studies on discovering miRNAs and analyzing their functions in model species, such as Arabidopsis and rice. Increasing investigations have been performed on important agricultural crops including soybean, conifers, and Phaselous vulgaris but no studies have been reported on discovering peanut miRNAs using a cloning strategy. RESULTS: In this study, we employed the next generation high through-put Solexa sequencing technology to clone and identify both conserved and species-specific miRNAs in peanuts. Next generation high through-put Solexa sequencing showed that peanuts have a complex small RNA population and the length of small RNAs varied, 24-nt being the predominant length for a majority of the small RNAs. Combining the deep sequencing and bioinformatics, we discovered 14 novel miRNA families as well as 75 conserved miRNAs in peanuts. All 14 novel peanut miRNAs are considered to be species-specific because no homologs have been found in other plant species except ahy-miRn1, which has a homolog in soybean. qRT-PCR analysis demonstrated that both conserved and peanut-specific miRNAs are expressed in peanuts. CONCLUSIONS: This study led to the discovery of 14 novel and 22 conserved miRNA families from peanut. These results show that regulatory miRNAs exist in agronomically important peanuts and may play an important role in peanut growth, development, and response to environmental stress.


Assuntos
Arachis/genética , MicroRNAs/genética , RNA de Plantas/genética , Clonagem Molecular , Sequência Conservada , Etiquetas de Sequências Expressas , Genoma de Planta , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA
20.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-299430

RESUMO

<p><b>OBJECTIVE</b>To investigate cyclooxygenase-2 (COX-2) expression and its relationship with mismatch repair (MMR) protein expression and microsatellite instability (MSI) in hereditary nonpolyposis colorectal cancer (HNPCC).</p><p><b>METHODS</b>A total of 28 cases of colorectal adenoma and 14 cases of colorectal carcinoma were collected between July 2003 and July 2007 from 33 HNPCC families. Sporadic colorectal adenoma (n=32) and carcinoma patients (n=24) served as controls. With samples of tumor tissues and normal colonic mucosa collected from the patients, the protein expressions of COX-2 and MMR (hMLH1, hMSH2, and hMSH6) were examined with immunohistochemical assay. Frequency of MSI in five standard MSI loci BAT25, BAT26, D2S123, D5S346, and D17S250 were analyzed by means of polymerase chain reaction.</p><p><b>RESULTS</b>The rate of COX-2 high-expression was 53.6% (15/28) and 42.9% (6/14) in HNPCC adenoma and carcinoma; 62.5% (20/32) and 91.7% (22/24) in sporadic adenoma and carcinoma, respectively. That rate was lower in HNPCC carcinoma than in sporadic carcinoma (Pü0.05). MMR-deletion rate and percentage of high-frequency MSI (MSI-H) in HNPCC carcinoma were higher than those in sporadic colorectal carcinoma [both 71.4% (10/14) vs. 12.5% (3/24), both Pü0.01]. Among the 10 MMR-deficient HNPCC carcinoma patients, COX-2 low-expression was observed in 8 cases (80.0%), while COX-2 high-expression was observed in all of the 4 MMR-positive HNPCC carcinoma cases (Pü0.05). In comparison to MMR positive HNPCC carcinoma, HNPCC adenoma, and sporadic carcinoma, COX-2 expression was significantly lower in corresponding MMR-deficient cases (all Pü0.05). The rates of COX-2 low-expression in HNPCC adenoma, HNPCC carcinoma, and sporadic carcinoma with MSI-H were significantly higher than those in the cases with microsatellite stability (all Pü0.05).</p><p><b>CONCLUSION</b>COX-2 is expressed at a low level in HNPCC carcinoma, different from the high COX-2 expression in sporadic carcinoma.</p>


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pareamento Incorreto de Bases , Sequência de Bases , Neoplasias Colorretais Hereditárias sem Polipose , Genética , Ciclo-Oxigenase 2 , Genética , Primers do DNA , Reparo do DNA , Imuno-Histoquímica , Repetições de Microssatélites , Genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...