Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 11 de 11
Filtrar
1.
Chinese Journal of Pathology ; (12): 332-337, 2022.
Artigo em Chinês | WPRIM | ID: wpr-935535

RESUMO

Objective: To assess the clinical features and treatment outcomes in patients with primary ovarian squamous cell carcinoma (POSCC). Methods: Fifteen patients with primary ovarian squamous cell carcinoma diagnosed from January 2009 to December 2018 in Cancer Hospital of the University of Chinese Academy of Sciences were collected. The expression of p16, hMLH1, hMSH2, hMSH6 and PMS2 in POSCC was detected by immunohistochemistry, and the status of high-risk human papillomavirus (HPV) by RNAscope test. Results: Squamous cell carcinoma with different degrees of differentiation was found in 15 cases, including three cases with high differentiation and 12 cases with medium to low differentiation. There were four cases with in situ squamous cell carcinoma, four cases with teratoma, one case with endometrial carcinoma/atypical hyperplasia, and one case with endometriosis. p16 was expressed in five cases (5/15), indicating coexisting high-risk HPV infection. There was no high-risk HPV infection in the remaining 10 cases, and p16 staining was negative. There was no deficient mismatch repair protein in all cases. The overall survival time (P=0.038) and progression free survival (P=0.045) of patients with high-risk HPV infection were longer than those without HPV infection. Conclusions: POSCC is more commonly noted in postmenopausal women and often occurs unilaterally. Elevated serological indexes CA125 and SCC are the most common finding. Morphologically, the tumors show variable degrees of differentiation, but the current data suggest that the degree of differentiation cannot be used as an independent prognostic index. High-risk HPV infection may be associated with the occurrence of POSCC, and that the prognosis of POSCC patients with HPV infection is better than that of patients without infection.


Assuntos
Feminino , Humanos , Carcinoma de Células Escamosas/patologia , Inibidor p16 de Quinase Dependente de Ciclina/análise , Imuno-Histoquímica , Infecções por Papillomavirus/diagnóstico , Prognóstico
2.
Rev. bras. ginecol. obstet ; 39(6): 288-293, June 2017. tab
Artigo em Inglês | LILACS | ID: biblio-898869

RESUMO

Abstract Objective To evaluate the expressions of biomarkers p16 and Ki-67 in low-grade (LG) or high-grade (HG) lesions, and to relate them to risk factors and the recurrence of these lesions. Methods A retrospective case-control study of 86 patients with LG and HG lesions who underwent a loop electrosurgical excision procedure (LEEP) between 1999 and 2004. The control group was composed of 69 women with no recurrence, and the study group, of 17 patients with recurrence. All patients were followed-up over a two-year period after surgery, and screened every six months, including cytology and colposcopy. Biopsy samples collected from LEEP were submitted to immunohistochemical analysis for p16 and Ki-67. The statistical analysis was performed using the Statistical Package for the Social Sciences software (SPSS, IBM-SPSS, Inc., Chicago, IL, US), with a significant p < 0.05. Results The biomarkers p16 and Ki-67, separately or combined, showed no relation to recurrence on the total analysis. However, evaluating specifically HG lesions, the positive expression (2+ and 3 + ) of p16/Ki-67 was associated with recurrence (0.010). In addition, p16 isolated was also more expressive in HG lesions (2+ and 3 + , p= 0.018), but it was unrelated to recurrence. Conclusion Proteins p16 and Ki-67, both isolated and combined, are not reliable primary markers for the recurrence of cervical lesions in the majority of LG lesions. However, analyzing only the group with prior diagnosis of HG lesions, the expressions of p16 and of p16/Ki-67 were associated with recurrence, and they may be useful in monitoring these cases.


Resumo Objetivo Avaliar as positividades dos biomarcadores p16 e Ki-67 em lesões de baixo grau (BG) ou de alto grau (AG), e relacioná-las com os fatores de risco e com a recidiva dessas lesões. Métodos Estudo retrospectivo caso-controle, com 86 pacientes com lesões de BG e AG, submetidas à conização por cirurgia de alta frequência entre 1999 e 2004. O grupo de controle foi constituído de 69 mulheres sem recidivas, e o grupo de estudo, de 17 pacientes que recidivaram. Todas as pacientes foram acompanhadas durante dois anos após a cirurgia, com controle a cada seis meses, incluindo citologia e colposcopia. As peças provenientes de cirurgia de alta frequência (CAF) foram submetidas a imunohistoquímica para p16 e Ki-67. A análise estatística foi realizada com o programa Statistical Package for the Social Sciences (SPSS, IBM-SPSS, Inc., Chicago, IL, EUA), com p significante quando < 0,05. Resultados Isoladamente ou em conjunto, p16 e Ki-67 não se relacionaram com as recidivas quando analisados na totalidade dos casos. Entretanto, avaliando especificamente as lesões de AG, a positividade (2+ e 3 + ) do conjunto p16/Ki-67 foi relacionada com recidiva (0,010). No mais, p16, isoladamente, foi também mais expresso nas lesões de AG (2+ e 3 + , p= 0,018), mas sem relação com recidiva. Conclusão Quando testadas na totalidade dos casos, as proteínas p16 e Ki-67, separadas ou em conjunto, se mostraram ineficientes como marcadores primários de recidiva de lesões precursoras. Entretanto, quando avaliadas somente no grupo diagnóstico prévio de lesão de AG, as expressões das proteínas p16 e p16/Ki-67 têm relação com a recidiva, e podem ser úteis no acompanhamento desses casos.


Assuntos
Humanos , Feminino , Lesões Pré-Cancerosas/diagnóstico , Biomarcadores Tumorais/análise , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/química , Antígeno Ki-67/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Recidiva Local de Neoplasia/diagnóstico , Estudos de Casos e Controles , Neoplasias do Colo do Útero/cirurgia , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Conização/métodos , Eletrocirurgia , Gradação de Tumores
3.
Rev. bras. ginecol. obstet ; 39(1): 21-25, Jan. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-843908

RESUMO

ABSTRACT Objective: To evaluate the diagnostic utility of the p16ink4a protein expression as a marker for adenocarcinoma of the cervix. Methods: In a cross-sectional study, p16ink4a expression was evaluated in 30 cervical biopsies from patients diagnosed with invasive adenocarcinoma from 2 reference clinics in Brazil, and compared with 18 biopsies of endocervical polyps (control cases). The performance of the tests for p16ink4a was evaluated using a conventional contingency table, and the Kappa (k) index was used to evaluate the agreement of the marker with the tissue diagnosis. Results: In total, 66% of the invasive adenocarcinoma cases were positive for p16ink4a. All of the adenomatous polyps cases used as negative controls were shown to be negative for p16ink4a. The marker showed a high sensitivity and a high negative predictive value. The Kappa index was good for p16ink4a (k 1/4 0.6). Conclusion: Considering the strong association between the p16ink4a marker and the cervical adenocarcinoma, its use represents an important tool for reducing incorrect diagnoses of adenocarcinoma and thereby avoiding overtreatment.


RESUMO Objetivo: Avaliar a utilidade diagnóstica da expressão da proteína p16ink4a como marcador de adenocarcinoma do colo. Métodos: Em estudo transversal, a expressão de p16ink4a foi avaliada em 30 biópsias cervicais de pacientes diagnosticadas com adenocarcinoma invasivo de colo uterino provenientes de dois serviços de referência no Brasil, comparando com achados em 18 biópsias de pólipos endocervicais (grupo de controle). Para avaliar a performance do teste, foi utilizada tabela de contingência convencional, e para avaliar a concordância com o diagnóstico, foi aplicado o índice de Kappa (k). Resultados: No total, 66% dos casos de adenocarcinoma invasivo foram positivos para p16ink4a. Todos os pólipos adenomatosos foram negativos para p16ink4a. O marcador mostrou uma alta sensibilidade e alto valor preditivo negativo. O índice de Kappa foi bom para p16ink4a (k 1/4 0.6). Conclusion: Considerando a forte associação entre o marcador p16ink4a e o adenocarcinoma cervical, seu uso representa uma ferramenta importante para reduzir o risco de diagnóstico incorreto de adenocarcinoma e, por conseguinte, evitar o excesso de tratamentos.


Assuntos
Humanos , Feminino , Adenocarcinoma/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/biossíntese , Neoplasias do Colo do Útero/metabolismo , Adenocarcinoma/química , Adenocarcinoma/patologia , Estudos Transversais , Inibidor p16 de Quinase Dependente de Ciclina/análise , Imuno-Histoquímica , Neoplasias do Colo do Útero/química , Neoplasias do Colo do Útero/patologia
4.
Rev. Col. Bras. Cir ; 43(1): 35-41, Jan.-Feb. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-779023

RESUMO

Objective: Io evaluate the expression of p16INK4a and p53 biomarkers in conization specimens from patients with high grade cervical intraepithelial neoplasia (HG-CIN), correlating them with the ability to predict the recurrence. Methods : we conducted a retrospective study of patients with HG-CIN in cervical biopsy treated with conization between January 1999 and January 2006 who had a minimum follow-up of 18 months. The expression of the p16 and p53 was assessed by tissue microarrays and correlated with disease recurrence. For analysis, we used the test of proportions (chi-square), considering value p<0.05, 95% CI and calculations of sensitivity, specificity and accuracy of these immunomarkers in predicting recurrence. Results : the series comprised 83 patients aged between 16 and 86 years (35±11.7), divided into two groups: 30 with HG-CIN recurrence (study group) and 53 without recurrence (control group). Mean age, parity, smoking and conization technique were similar in both groups. The p53 expression was present in 43% of the study group and 57% of the control group, and the p16 was present in 43% of the study group and in 57% of the control group (p>0.05). p53 had a positive predictive value (PPV) of 42% and negative predictive value (NPV) of 73%, sensitivity 70%, specificity of 47% and accuracy of 59%. The p16, PPV 42%, NPV 72%, sensitivity 66%, specificity of 49% and accuracy of 56%. Conclusion : immunohistochemistry expression of p53 and p16 showed low sensitivity and low specificity as predictors of HG-CIN recurrence after conization treatment.


Objetivo : avaliar a expressão dos biomarcadores p16INK4a e p53, nas peças de conização de pacientes com neoplasia intraepitelial cervical de alto grau (NIC-AG), correlacionando com a capacidade de predizer o risco de recorrência. Métodos : estudo retrospectivo de pacientes com NIC-AG em biópsia de colo uterino, tratadas por conização, entre janeiro de 1999 e janeiro de 2006 e seguimento mínimo de 18 meses. A expressão dos biomarcadores p16 e p53 foi avaliada através de técnica de microarranjos teciduais e correlacionada com a recorrência da doença. Para análise utilizou-se o teste das proporções (qui-quadrado), considerando valor p<0,05, IC95% e cálculos de sensibilidade, especificidade e acurácia destes imunomarcadores na predição de recorrência. Resultados : oitenta e três pacientes, idade entre 16 e 86 anos (35±11,7), divididas em dois grupos: 30 com recorrência da NIC-AG (grupo estudo) e 53 sem recorrência (grupo controle). A média de idade, paridade, hábito de fumar e técnica de conização foram semelhantes nos dois grupos. A expressão do p53 esteve presente em 43% do grupo estudo e 57% do grupo controle e para o p16 esteve presente em 43% do grupo estudo e 57% do grupo controle (p>0,05). O p53 apresentou valor preditivo positivo (VPP) de 42% e valor preditivo negativo (VPN) de 73%, sensibilidade de 70%, especificidade de 47% e acurácia de 59%. O p16, VPP de 42% e VPN de 72%, sensibilidade de 66%, especificidade de 49% e acurácia de 56%. Conclusão : a expressão imunoistoquiímica do p53 e do p16 apresentaram baixa sensibilidade e baixa especificidade como marcadores capazes de predizer a recorrência da NIC-AG tratada por conização.


Assuntos
Humanos , Feminino , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Neoplasias do Colo do Útero/química , Proteína Supressora de Tumor p53/análise , Displasia do Colo do Útero/química , Inibidor p16 de Quinase Dependente de Ciclina/análise , Recidiva Local de Neoplasia , Imuno-Histoquímica , Neoplasias do Colo do Útero/cirurgia , Neoplasias do Colo do Útero/patologia , Valor Preditivo dos Testes , Estudos Retrospectivos , Displasia do Colo do Útero/cirurgia , Displasia do Colo do Útero/patologia , Conização , Pessoa de Meia-Idade
5.
Indian J Pathol Microbiol ; 2012 Jul-Sept 55(3): 339-342
Artigo em Inglês | IMSEAR | ID: sea-142263

RESUMO

Background: The repair of the immature squamous epithelium following HPV infection may mimic HSIL in adolescent women. Aim: to study the utility of p16 INK4a and Ki-67 in diagnosis of cervical squamous lesions in adolescents and young adults. Materials and Methods: In a cross-sectional study, the evaluation of p16 INK4a and Ki-67 immunohistochemistry was performed on 72 cervical biopsies of adolescents and young adults women diagnosed as negative for malignancy and intraepithelial lesion (NML) (n = 18) or positive for low grade (LSIL) (n = 31) and high grade (HSIL) (n = 23) squamous intraepithelial lesions in two references services in Fortaleza-Brazil. Data was evaluated using Fisher's test and Kappa index. Results: p16 INK4a was positive in 81% of HSIL, 19% of LSIL and in no NML (P < 0.0001). Ki-67 was positive in 74%, 32% and 5.5% of HSIL, LSIL and NML, respectively. p16 INK4a and Ki-67 in the diagnosis of HSIL showed high sensitivity and negative predictive value. Kappa index was very good for p16 INK4a (k = 0.72). Conclusions: In adolescents and young adults p16 INK4a alone or with Ki-67 represents important tool to reduce mistaken diagnosis of HSIL and to avoid overtreatment.


Assuntos
Adolescente , Biópsia , Brasil , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/patologia , Colo do Útero/patologia , Estudos Transversais , Inibidor p16 de Quinase Dependente de Ciclina/análise , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/patologia , Adulto Jovem
6.
Yonsei Medical Journal ; : 519-525, 2005.
Artigo em Inglês | WPRIM | ID: wpr-16554

RESUMO

Pancreatic cancer is a disease with poor prognosis mainly due to low resection rates and late diagnosis. To increase resectability and improve survival rates, a better understanding of pancreatic cancer pathogenesis and more effective screening techniques are required. New methods, such as genetic and molecular alterations, may suggest novel approaches for pancreatic cancer diagnosis and treatment. We immunohistochemically investigated 44 formalin-fixed, paraffin-embedded specimens of pancreatic ductal adenocarcinoma using monoclonal anti-p16 antibodies and monoclonal anti-p53 antibodies. The expressions of p16 and p53 proteins were compared using the Chi-square test with SPSS. Disease-free survival was analyzed using the Kaplan-Meier method, verified by the Log- Rank test. Loss of p16 expression was noted in 20 (45.5%) cases and aberrant p53 protein expression was detected in 14 (31.8%) cases. Loss of p16 expression was associated with a higher incidence of lymph node metastasis (p=0.040) and a more advanced stage (p=0.015), although there was no significant correlation between p16 expression and survival. Aberrant p53 protein expression correlated with histologic grade (p= 0.038). Disease-free survival rate was significantly lower in the aberrant p53 protein positive group compared to the negative group (p=0.029). From our results, we suggest that p53 is not a prognostic factor; however, p16 and p53 genes do play important roles in the progression of pancreatic ductal adenocarcinoma.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Genes p16 , Genes p53 , Imuno-Histoquímica , Estadiamento de Neoplasias , Neoplasias Pancreáticas/química , Inibidor p16 de Quinase Dependente de Ciclina/análise , Proteína Supressora de Tumor p53/análise , Caracteres Sexuais
7.
Journal of Korean Medical Science ; : 636-642, 2005.
Artigo em Inglês | WPRIM | ID: wpr-147613

RESUMO

Methylation of p16 is an important mechanism in cervical carcinogenesis. However, the relationship between cervical squamous cell carcinoma (SCC) and Epstein-Barr virus (EBV) remains controversial. Here, we explored whether EBV infection and/or p16 gene inactivation would play any role in cervical carcinogenesis. Eighty-two specimens included 41 invasive SCCs, 30 cervical intraepithelial neoplasm (CIN; CIN 1, 11 cases, CIN II, 3 cases, CIN III 16 cases) and 11 nonneoplastic cervices. EBV was detected by polymerase chain reaction (PCR) for EBNA-1 and in situ hybridization for EBER-1. The p16 methylation-status and the expression of p16 protein were studied by methylation-specific PCR and immunohistochemistry, respectively. The materials were divided into four groups: 1) nonneoplastic cervices, 2) CIN I, 3) CIN II-III and 4) invasive SCCs. p16 methylation and p16 immunoexpressions increased in CIN and invasive SCCs than nonneoplastic tissue. p16-methylation and p16-immunoreactivities were higher in the EBV-positive group (p=0.009, p<0.001) than in the EBV-negative group. EBV was detected more frequently in CIN and SCCs than nonneoplastic cervices. In conclusion, a correlation between p16 methylation, p16 immunoreactivity and the detection of EBV strongly suggested that the cooperation of EBV and p16 gene may play a synergic effect on cell cycle deregulation.


Assuntos
Feminino , Humanos , Carcinoma de Células Escamosas/genética , Estudo Comparativo , Inibidor p16 de Quinase Dependente de Ciclina/análise , Metilação de DNA , DNA Viral/genética , Infecções por Vírus Epstein-Barr/genética , Antígenos Nucleares do Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Imuno-Histoquímica , Hibridização In Situ , Reação em Cadeia da Polimerase , Lesões Pré-Cancerosas/genética , RNA Viral/genética , Neoplasias do Colo do Útero/genética
8.
Saudi Medical Journal. 2004; 25 (12): 1922-30
em Inglês | IMEMR | ID: emr-68552

RESUMO

Inactivation of p53 and p16 tumor suppressor genes, and apoptosis which is crucial in carcinogenesis have commonly been studied in oral squamous cell carcinoma [OSCC]. However, their prognostic value has not yet been clearly established. This study was conducted in the Department of Oral Pathology, Faculty of Dentistry, Gazi University, Ankara, Turkey during the period 2002 to 2003 on formalin-fixed paraffin embedded tissue specimens of 12 lip and 18 intraoral primary squamous cell carcinoma cases. The expression of p53 and p16 proteins were studied by immunohistochemistry, and the apoptosis by TdT-mediated dUTP-biotin nick end-labeling [TUNEL] methods. The possible prognostic value of p53, p16 expression and apoptotic index [AI] value in OSCC were examined on the basis of their correlation with mode of invasion [MI] grading system. Seven lip [58%] and 9 intraoral cancer [50%] cases showed p53 positivity; where 5 lip [42%] and 15 intraoral cancer [83%] cases showed loss of p16 protein. P53 positive cases increased parallel to MI grade where the AI value decreased. There was not any correlation either between p16 expression and MI grade or AI value. The mean AI value was found as 1,884. Apoptotic index values were higher in invasive site of tumors, and it was statistically significant in MI grade 2 OSCC cases. Apoptotic index value of both central and invasive sites were lowest in MI grade 4 cases. The present findings revealed that p53 mutations alone, may play a role in pathogenesis of lip cancers but not in intra OSCC. P16 may have a greater role in the development of intra OSCC. P53 positivity and low AI value may be a predictor of poor prognosis in OSCC


Assuntos
Humanos , Masculino , Feminino , Carcinoma de Células Escamosas/patologia , Neoplasias Labiais/patologia , Apoptose/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/análise , Invasividade Neoplásica
9.
Yonsei Medical Journal ; : 722-728, 2002.
Artigo em Inglês | WPRIM | ID: wpr-160896

RESUMO

The ability of viral oncoproteins to subvert cell cycle checkpoints may constitute a mechanism by which viral oncoproteins induce genetic instability. HPV 16 E6 and E7 disrupt cell cycle checkpoints, particularly affecting nearly all cyclin-dependent kinase inhibitors linked to the G1- and G2- checkpoints, in each case by means of a different mechanism. HPV 16 E7 shows homology with the pRb binding sites of cyclin D1, which consequently releases E2F. In addition, E7 directly binds to p21, and releases PCNA and other S-phase promoting genes. In turn, released E2F activates cyclin E, and cyclin E accelerates p27 proteolysis as a function of the antagonistic reaction of its own inhibitor. The induction of p16 expression is assumed to be indirectly associated with E7, which is upregulated only after prolonged inactivation of Rb. HPV 16 E6 decreased the fidelity of multiple checkpoints controlling both entry into and exit from mitosis, with the mechanism of p53 inactivation. In addition, HPV 16 E6 increased the sensitivity to chemically induced S-phase premature mitosis and decreased mitotic spindle assembly checkpoint function. Alongside the impressive advances made in the understanding of the molecular mechanisms, which HPV disrupts, the validity of these conclusions should be evaluated in the diagnostic and prognostic fields.


Assuntos
Feminino , Humanos , Neoplasias do Colo do Útero/patologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/análise , Fase G1 , Fase G2 , Proteínas dos Microfilamentos/análise , Infecções por Papillomavirus/patologia , Papillomaviridae , Antígeno Nuclear de Célula em Proliferação/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Infecções Tumorais por Vírus/patologia
10.
Journal of Korean Medical Science ; : 424-432, 2001.
Artigo em Inglês | WPRIM | ID: wpr-79892

RESUMO

Deranged expression of cell cycle modulators has been reported to contribute to the development and progression of hepatocellular carcinoma (HCC). However, their expression patterns remain poorly understood in hepatitis B virus (HBV)-related HCC, which constitutes about 65-70% of HCC in Korea. The aims of this study were to evaluate the expressions of G1-S modulators in HBV-related HCCs and dysplastic nodules (DNs), and to correlate with the histopathologic features of HCCs. Immunohistochemical expressions of cyclin D1, cyclin E, p53, p27, p21, p16, Rb, and PCNA proteins were investigated in 80 HCCs and 22 DNs. Cyclin D1 overexpression showed positive relationships with advanced tumor stage, poor differentiation, larger tumor size, microvascular invasion, intrahepatic meta-stasis, no tumor capsule formation, infiltrative growth, aberrant p53 expression, and high PCNA labeling index (LI) of HCC (p<0.05). Aberrant p53 expression showed positive relationship with poor differentiation of HCC (p<0.01). Expression of cyclin D1 or p53 was not observed in DNs. The p27 LI and p16 LI were lower in HCCs with intrahepatic metastasis (p<0.05). Cyclin D1 overexpression and aberrant p53 expression could be associated with the progression of HBV-related HCC, and might have a less crucial role in the DN-HCC sequence. In addition, elevated expression of p27 and p16 proteins might have inhibitory action to the intrahepatic metastasis of HBV-related HCC.


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Carcinoma Hepatocelular/química , Ciclina D1/análise , Fase G1 , Hepatite B/complicações , Imuno-Histoquímica , Neoplasias Hepáticas/química , Proteínas dos Microfilamentos/análise , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/virologia , Antígeno Nuclear de Célula em Proliferação/análise , Inibidor p16 de Quinase Dependente de Ciclina/análise , Proteína Supressora de Tumor p53/análise , Proteína do Retinoblastoma/análise , Fase S
11.
Journal of Korean Medical Science ; : 555-559, 2000.
Artigo em Inglês | WPRIM | ID: wpr-150734

RESUMO

Recent evidence shows that transcriptional silencing as a consequence of hypermethylation of CpG islands is an important mechanism in the inactivation of p16INK4 tumor suppressor gene. This study is designed to clarify the significance of p16INK4 hypermethylation in 23 cases of glioblastomas (GBMs) by methylation-specific polymerase chain reaction (PCR) and p16 immunostaining. Fourteen cases (60.9%) out of 23 GBMs revealed hypermethylation on p16. p16 immunostaining revealed that 13 (93%) of these 14 hypermethylation cases showed complete loss of immunoreactivity and only one (7%) case retained immunoreactivity. Among 9 methylation-negative cases, 4 were immunonegative, which might be related to mutations or deletions other than hypermethylation. The most significant finding was that of 17 cases with immunonegativity, 13 cases (76.5%) showed hypermethylation. We reconfirmed that p16 hypermethylation may be one of the major mechanisms of tumorigenesis of GBMs and the results between the methylation specific-PCR study and p16 immunostaining had a good correlation.


Assuntos
Adulto , Feminino , Humanos , Masculino , Regiões 5' não Traduzidas/metabolismo , Regiões 5' não Traduzidas/genética , Elementos Antissenso (Genética) , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/química , Ilhas de CpG/fisiologia , Metilação de DNA , Inativação Gênica/fisiologia , Glioblastoma/patologia , Glioblastoma/genética , Glioblastoma/química , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/análise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA