Detection of DNA methylation of HYAL2 gene for differentiating malignant from benign thyroid tumors / 南方医科大学学报

OBJECTIVE@#To assess the value of DNA methylation level of HYAL2 gene as a molecular marker for differential diagnosis of malignant and benign thyroid tumors.@*METHODS@#DNA methylation of HYAL2 gene in tissue specimens of 190 patients with papillary thyroid cancer (PTC) and 190 age- and gender-matched patients with benign thyroid tumors was examined by mass spectrometry, and the protein expression of HYAL2 was detected immunohistochemically for another 55 pairs of patients. Logistic regression analysis was performed to calculate the odds ratio (OR) and evaluate the correlation of per 10% reduction in DNA methylation with PTC. Receiver operating characteristic (ROC) curve analysis was performed and the area under curve (AUC) was calculated to assess the predictive value of alterations in HYAL2 methylation.@*RESULTS@#Hypomethylation of HYAL2_CpG_3 was significantly correlated with early-stage PTC (OR=1.51, P=0.001), even in stage I cancer (OR=1.42, P=0.007). Age-stratified analysis revealed a significantly stronger correlation between increased HYAL2_CpG_ 3 methylation and early-stage PTC in patients below 50 years than in those older than 50 years (OR: 1.89 vs 1.37, P < 0.05); ROC analysis also showed a larger AUC of 0.787 in younger patients. The results of immunohistochemistry showed that patients with PTC had significantly higher protein expressions of HYAL2 than patients with benign tumors.@*CONCLUSION@#The alterations of DNA methylation level of HYAL2 gene is significantly correlated with early-stage PTC, suggesting the value of DNA methylation level as a potential biomarker for differentiation of malignant from benign thyroid tumors.

Expression of Endogenous Beta Retroviruses and Hyal-2 mRNA in Immune Organs of Fetuses and Lambs / 中国病毒学·英文版

Endogenous beta retroviruses (enJSRV) are highly homologous with Jaagsiekte sheep retrovirus (exJSRV),this exogenous retrovirus is the aetiological agent of ovine pulmonary adenocarcinoma (OPA).The aim of this study was to clarify the function of enJSRV and the immunological mechanisms of its corresponding antibody,that is undetectable in JSRV-infected ovine serum.The expression of enJSRV envelope protein and Hyal-2 mRNA in immune organs and lungs of ovine fetuses and lambs were analyzed by Real-Time reverse transcription PCR and In Situ Hybridization using specific probes.In Situ Hybridization results indicated that the enJSRV envelope protein and Hyal-2 mRNA were expressed in thymus,spleen,mesenteric lymph nodes and lungs at different times,while no positive signals were detected in the negative controls.On the other hand,results from Real-Time reverse transcription PCR analysis showed that in 130d fetuses and 3d newborn lambs the enJSRV mRNA levels were much higher in organs associated with the immune system than that in lungs,especially in the thymus and spleen,but levels of Hyal-2 mRNA expression was not significantly different in all collected tissue.These results provided evidence from an immunology point of view to understand why the circulating antibodies against exJSRV are undetectable in JSRV-infected ovine,and will help to unravel the pathogenesis of JSRV-infected ovine.