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Objective To assess the correlation of promoter methylation of DAPK1,RAR-β and MGMT with cervical lesions from cytology to histology,and to reveal the clinical value of DNA methylation in diagnosis of cervical intraepithelial neoplasia (CIN).Methods A total of 103 random-selected cervical samples were collected from residual liquid-based cytology specimens after clinical use in cytopathological diagnosis in outpatient clinic of obstetrics and gynecology,Peking Union Medical Collage Hospital from March 2010 to October 2010.Informed consent was obtained from each woman before the initiation of the study.The methylation seusitive-high resolution melt (MS-HRM) assay was used to evaluate promoter methylation of three genes ( DAPKI,RAR-β and MGMT) in 103 biopsy-confirmed liquid-based cervical cytology samples.Methylation levels and high-risk HPV DNA loading ( HC Ⅱ values) were analyzed in relation to both cytological and histological diagnosis.Results The methylation level of all three genes showed significant difference among the different cytological groups ( P =0.000,0.011 and 0.002,respectively).The methylation level of DAPK1 and RAR-β showed significant difference among the different histological groups ( P =0.000 and 0.021 ),while there was no significant difference for MGMT.DAPK1 methylation levels was 1.47％ in the CIN Ⅱ/high-grade precancerous lesions group,and 20.98％ in the normal/CIN I groups ( P =0.000 ),but there was no significant difference between CIN I/high-grade precancerous lesions and normal/CIN Ⅰ groups for RAR-β and MGMT.The combination of DAPK1/HR-HPV loading showed a sensitivity of 0.825 and an area under the receiver operating characteristic curve (ROC) curve (AUC) of 0.695 as diagnostic methods for detecting CIN Ⅱ/high-grade precancerous lesions.Conclusions DNA methylation such as DAPK1 and RAR-β,in combination with HR-HPV detection,may serve as biomarkers to detect CIN Ⅱ/high-grade precancerous lesions.Detection of methylated DNA from liquid-based cervical cytology specimens is technically feasible with the MS-HRM assay.
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BACKGROUND: While qualitative analysis of methylation has been reviewed, the quantitative analysis of methylation has rarely been studied. We evaluated the methylation status of CDKN2A, RARbeta, and RASSF1A promoter regions in non-small cell lung carcinomas (NSCLCs) by using pyrosequencing. Then, we evaluated the association between methylation at the promoter regions of these tumor suppressor genes and the clinicopathological parameters of the NSCLCs. METHODS: We collected tumor tissues from a total of 53 patients with NSCLCs and analyzed the methylation level of the CDKN2A, RARbeta, and RASSF1A promoter regions by using pyrosequencing. In addition, we investigated the correlation between the hypermethylation of CDKN2A and the loss of p16INK4A immunoexpression. RESULTS: Hypermethylation of CDKN2A, RARbeta, and RASSF1A promoter regions were 16 (30.2%), 22 (41.5%), and 21 tumors (39.6%), respectively. The incidence of hypermethylation at the CDKN2A promoter in the tumors was higher in undifferentiated large cell carcinomas than in other subtypes (p=0.002). Hyperrmethylation of CDKN2A was significantly associated with p16INK4A immunoexpression loss (p=0.045). With regard to the clinicopathological characteristics of NSCLC, certain histopathological subtypes were found to be strongly associated with the loss of p16INK4A immunoexpression (p=0.016). Squamous cell carcinoma and undifferentiated large cell carcinoma showed p16INK4A immunoexpression loss more frequently. The Kaplan-Meier survival curves analysis showed that methylation level and patient survival were barely related to one another. CONCLUSION: We quantitatively analyzed the promoter methylation status by using pyrosequencing. We showed a significant correlation between CDKN2A hypermethylation and p16INK4A immunoexpression loss.
Subject(s)
Humans , Carcinoma, Large Cell , Carcinoma, Non-Small-Cell Lung , Carcinoma, Squamous Cell , DNA Methylation , Evaluation Studies as Topic , Genes, p16 , Genes, Tumor Suppressor , Incidence , Kaplan-Meier Estimate , Lung , Methylation , Promoter Regions, Genetic , Receptors, Retinoic Acid , Sequence Analysis, DNA , Tumor Suppressor ProteinsABSTRACT
Objective To illustrate the clinical relevance of distinct PML-RARα fusion gene isoforms in acute promyelocytic leukemia (APL). Methods The nested reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect the long (L) or short (S) PML-RARα fusion gene isoforms in 92 newly diagnosed APL so as to evaluate the clinical feature, therapeutic reaction and prognosis of the two fusion gene isoforms. Results PML-RARα fusion gene was positive in all 92 APL patients, of which 52(56.5 %) was L type and 40 (43.5 %) was S type. There were no significant differences between L type and S type in the aspect of sex, age, white blood cell count,the percentage of bone marrow blasts plus promyeloeytes and chromosome before treatment. And there were no significant differences between the two isoforms in complete remission (CR) rate, the time of getting CR as well as the occurrence of retinoic acid syndrome (RAS), disseminated intravascular coagulation (DIC), intraeranial hemorrhage. Also, there were no significant differences in overall survival rate (OS) and relapse-free survival rate (RFS) between the two isoforms. Conclusion PML-RARα fusion gene isoforms in APL were not correlated with clinical therapeutic effect or prognosis.
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Objective: To investigate the effect of retinoic acid on the differentiation and development of B lymphocytes, and explore the mechanism of vitaminA in increasing the production of antibodies. Method: In vitro cultured cells from children’s normal mesentery lymph nodes, before and after administration of retinoic acid or retinoic acid antagonist, the changes of cell surface markers were analyzed by flowcytometry to observe the differentiation and maturation of B cells. Results: During culture in vitro, the percent of mature CD19+IgM+ B cells increased and relatively immature CD19+IgM- B cells decreased gradually, and the changes were especially obvious at 48 h. The administration of retinoic acid further increased the percent of CD19+IgM+ B cells, and the enhancement was markedly at 24 and 48 h (P
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Objective To study level of the expression of RAR? mRNA in the skin lesions of patients with psoriasis vulgaris. Methods The biopsies were taken from skin lesions in 20 patients with psoriasis vulgaris and the skin of 10 normal controls, and levels of RAR? mRNA were investigated with RT-PCR. Results The level of RAR?mRNA was significanlly lower in the epidermis of patients with psoriasis vulgaris than that in the control(P
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Objective To study the level of expression of RAR?/RXR?mRNA in skin lesions of patients with psoriasis vulgaris.Methods The skin biopsies were collected fro mskin lesions in 20cases of psoriasis vulgaris and 10normal controls.Expression o f RAR?/RXR?mRNA was detected by RT -PCR.Results Expression levels of RXR?mRNA were 0.19760?0.0933in epiderm ides from psoriatic lesions,which were markedly lower than those in normal controls(0.5867?0.0132)(P0.05).Conclusion The results indicate that decreased expression of RXR?mRNA might be related to the pathogen esis of psoriasis.