Endocrine Abstracts

Objective: The tumor suppressor gene methylation lead to gene silencing, it plays an important role in thyroid tumor occurrence and development. This study examined the tumor suppressor gene (PTEN, RASSF1A, DAPK, RARβ2) DNA methylation and mRNA expression status in the peripheral blood of patients with nodular thyroid disease. Discuss its clinical significance. For the benign and malignant thyroid nodules early identification of molecular diagnosis is based.

Method: Select in September 2007–December 2011 a total of 200 cases of nodular thyroid disease diagnosed (including 66 cases of patients with nodular goiter, 50 cases of thyroid adenoma, 24 cases of thyroid cancer and 60 cases of normal control group as a research object, mining fasting venous blood, by the specificity MSPPCR methods to detect PTEN, RASSF1A, DAPK and RARβ2 methylation, by RT-PCR method to detect the peripheral blood of the four genes mRNA expression using SPSS 13.0 statistical software.

Result: In the high methylation status of DAPK, RARβ2, PTEN, RASSF1A gene in the peripheral blood of thyroid cancer, adenoma and nodular goitre patients, and to compare the methylation rate of thyroid cancer>adenoma>nodular goiter. Tip the four gene promoter methylation is common in molecular biological events in the peripheral blood of thyroid tumors. Closely related to the occurrence and development of thyroid tumors. The four genes mRNA expression in the peripheral blood of thyroid cancer and adenoma reduce or even missing, and was negatively correlated with four gene methylation. Tip four genes promoter methylation may be one of the reasons causing gene expression to reduce the missing. The four genes promoter methylation and mRNA expression is realated with lymph node metastasis in thyroid cancer patients. No relationship between nodule size, calcification and ECT.

Conclusion: MSP and RT-PCR method combined detection of nodular thyroid disease in peripheral blood of tumor suppressor gene RARβ2, of DAPK and PTEN, RASSF1A gene methylation and expression.For early malignant and benign thyroid nodules to identify the diagnosis. Determination of MSPDNA and RNA in peripheral blood play an important role in tumor early diagnosis, cancer screening and other aspects.