The Study Of Death-Associated Protein Kinase Alterations In Circulating DNA Of Transitional Cell Carcinoma Of The Bladder: Promoter Methylation And Homozygous Deletion

The expression of death-associated protein kinase in the transitional cell carcinoma of the bladderObjective To investigate the expression of death-associated protein kinase in the transitional cell carcinoma of the bladder and the relation to the cause and the clinical stage of tumors.Methods Immunohistochemistry and RT-PCR were used to study the expression of death-associated protein kinase protein and mRNA in 45 tumor tissue and 20 peritumor tissue. To investigate the relationship between the gene expression with the cause and clinical stage of tumor.Results Under the immunohistochemistry study, there were 17 of 45 tumor cases reveal the decrease of death-associated protein kinase protein(superficial 2 cases, invasion 15 cases), 20 peritumor tissue have normal protein expression; Under the RT-PCR study, there were 15 of 45 tumor cases reveal the decrease of death-associated protein kinase mRNA(superficial 1 cases, invasion 14 cases), 20 peritumor tissue have normal mRNA expression. The expression of death-associated protein kinase in tumor tissue were significantly lower than that of peritumor tissue(P﹤0.01), and the expression of death-associated protein kinase were significantly decrease in higher clinical stage tumor to lower ones(P﹤0.01).Conclusion The low expression of death-associated protein kinase was related with the cause and clinical stage of transitional cell carcinoma of the bladder. Death-associated protein kinase maybe a novel marker of transitional cell carcinoma of the bladder for diagnosis and prognosis. The study of death-associated protein kinase(DAPK) alterations in circulating DNA of transitional cell carcinoma of the bladder(TCCB): Promoter methylationObjective To investigate the promoter methylation of death-associated protein kinase in the transitional cell carcinoma of the bladder, elucidate the relationship between promoter methylation with gene silence and the biological behavior of the transitional cell carcinoma of the bladder.Methods We collected vein blood samples from 45 cases primary transitional cell carcinoma of the bladder, and 30 cases urinary stone as control group. The circulating DNA was extracted by DNA EXTRACTION KIT from GENTRA. The promoter primer was designed by software, and the method of methylation special PCR(MSP) was set up to analyze the promoter methylation of death-associated protein kinase. Combination with previous studies and the clinical data, the the relationship between promoter methylation with gene silence and tumor biological behaviour should be elucidated better.Results In this study we have examined 45 transitional cell carcinoma of the bladder for promoter methylation using MSPCR, 10 of 45 cases(22%) had promoter hypermethylation. There was 1case was superficial and the other 9 were invasive. From all above methylation cases, there were 9cases appeared gene silence. The control group was no anomaly during the inveatigation. Statistical analysis suggested that promoter methylation of death-associated protein kinase were significantly associated with low expression or deletion of death-associated protein kinase(P<0.05), and invasive transitional cell carcinoma of the bladder (P<0.05).Conclusion The Promoter methylation of death-associated protein kinase are important factor that influence of death-associated protein kinase expression. The detections of promoter methylation in circulating DNA of transitional cell carcinoma of the bladder could estimate the stage of transitional cell carcinoma of the bladder in early periods, and it should be a micro-invasive examinations for nonage diagnosis of transitional cell carcinoma of the bladder. The study of death-associated protein kinase(DAPK) alterations in circulating DNA of transitional cell carcinoma of the bladder(TCCB): Promoter homozygous deletionObjective To investigate the promoter homozygous deletion of death-associated protein kinase in the transitional cell carcinoma of the bladder, elucidate the relationship between promoter homozygous deletion with gene silence and the biological behavior of the transitional cell carcinoma of the bladder.Methods We collected vein blood samples from 45 cases primary transitional cell carcinoma of the bladder, and 30 cases urinary stone as control group. The circulating DNA was extracted by DNA EXTRACTION KIT from GENTRA. The promoter primer was designed by software, and the method of differential PCR was set up to analyze the promoter homozygous deletion of death-associated protein kinase. Combination with previous studies and the clinical data, the relationship between promoter homozygous deletion with gene silence and tumor biological behaviour should be elucidated better.Results In this study we have examined 45 transitional cell carcinoma of the bladder for promoter homozygous deletion using differential PCR, 6 of 45 cases(13.3%) had promoter homozygous deletion. There was 1 case was G2 and the other 5 were G3. All above homozygous deletion cases appeared gene silence. The control group was no anomaly during the investigation. Statistical analysis suggested that promoter homozygous deletion of death-associated protein kinase were significantly associated with low expression or deletion of death-associated protein kinase(P<0.01), and clinical grade of transitional cell carcinoma of the bladder (P<0.01). Conclusion The Promoter homozygous deletion of death-associated protein kinase areimportant factor that influence of death-associated protein kinase expression. The detections of promoter homozygous deletion in circulating DNA of transitional cell carcinoma of the bladder could estimate the clinical grade of transitional cell carcinoma of the bladder in early periods, and it should be a micro-invasive examinations for nonage diagnosis of transitional cell carcinoma of the bladder.