TCF21Methylation And Clinical Potential In Bladder Carcinoma Therapy

Objective: Bladder cancer is a common malignant tumor, there are about150,000people death around the world each year. So far, there are no moleculartargeted drugs available for the treatment of this disease. TCF21(TranscriptionFactor21) is a tumor suppressor gene encoding a transcription factor21.Methylation of TCF21gene in head and neck cancer, lung cancer and renal cellcancer, has been reported, however, TCF21gene methylation and its clinicalapplication potential in bladder cancer have not been fully explained, especially themethylation of TCF21gene in the quantitative detection of bladder cancer not beenreported. The aim of this study on the relationship between TCF21gene methylationand expression, and characterization of TCF21gene methylation in bladder cancer, isto prove that the quantitative detection of TCF21gene methylation in urinesediments of bladder cancer, can become one of the important means of thediagnosis and prognosis in bladder cancer therapy.Methods: Bladder cancer cell line5637treated by demethylating reagentDecitabine and Zebularine in vitro experiments was conducted, then TCF21genemethylation levels of bladder cancer cell line5637were detected quantitatively bypyrosequencing, TCF21mRNA and protein levels of bladder cancer cell line5637were detected by double labeling fluorescent probe technique and Western-blotmethod respectively; TCF21gene methylation levels in83cases of bladder cancertissues and19cases of normal bladder tissues were detected by pyrosequencing,Mann-Whitney U Test statistical method was used in TCF21gene methylation levelsof bladder cancer tissues compared with gender, age, smoking history, tumor gradeand stage five clinical parameters, Spearman Correlation statistical method was usedto analyze the correlation between TCF21gene methylation levels and patient age,tumor grade and stage three clinical parameters in bladder cancer tissues; TCF21gene methylation levels in33cases of bladder cancer urine sediments and10casesof normal urine sediments were detected by pyrosequencing, Mann-Whitney U Test statistical method was used in TCF21gene methylation levels of bladder cancerurine sediments compared with gender, age, smoking history, tumor grade and stagefive clinical parameters, Spearman Correlation statistical method was used toanalyze the correlation between TCF21gene methylation levels and patient age,tumor grade and stage three clinical parameters in bladder cancer urine sediments,the receiver operating characteristic (ROC) was used in the diagnosis of TCF21genemethylation levels compared with bladder cancer tissues and urine sediments.Results: The present study revealed that treatment of bladder cancer cell line5637with the demethylating reagent Decitabine and Zebularine resulted in adecrease in TCF21gene methylation levels and an increase in TCF21mRNA andprotein expression; Furthermore, TCF21methylation levels in bladder cancer tissueswere significantly higher than those of the normal, and also higher than those ofpatients with renal cell carcinoma, there were age differences in TCF21genemethylation levels; TCF21methylation levels in the bladder cancer urine sedimentswere significantly higher than those of the normal, there were tumor gradedifferences in TCF21gene methylation level, there were correlation between tumorgrade and TCF21gene methylation levels, the areas under TCF21ROC curves ofbladder cancer tissues and urine sediments were higher than the reference value, butthe TCF21specificity of bladder cancer urine sediments was higher than that ofbladder cancer tissues.Conclusion: This study demonstrates that abnormal methylation levels ofTCF21CpG islands play an important role in the regulation of TCF21expression;TCF21gene can be used as a biomarker for diagnosis and prognosis in bladdercancer therapy; The quantitative detection of TCF21gene methylation levels inbladder cancer urine sediments, is likely to be one of the important means of thediagnosis and prognosis in bladder cancer.