Methylation Change Of Mir-203 Gene And Its Significance In Hazakh's Esophageal Squamous Cell Carcinoma In Xinjiang Province, China

Objective:To detect the methylation status of miR-203 gene of the Hazakh's esophageal squamous cell carcinoma, non-cancerous adjacent tissue and normal esophageal squamous epithelium, and explore the correlation and significance between the methylation of CpG islands of miR-203 and ESCC.Methods:The genomic DNA of 191 samples, including 99 cases of esophageal squamous cell carcinoma (ESCC),46 cases of non-cancerous adjacent tissue (NCAT) and 46 cases of normal esophageal squamous epithelium (NESE), were modified by the EZ DNA MethylationTM Kit. The CpG islands methylation status of miR-203 gene of 191 cases was detected by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). All of the methylation data were analyzed by the software of Cluster3.0, GraphPad Prism 5 and SPSS 16.0.Results:1. Comparison of the methylation rate of miR-203₁5 among ESCC, NCAT and NESE: miR-203₁5 were hypermethylated in ESCC and NCAT, and there were 10 CpG units, which were CpG₇.8, CpG₁0, CpG₁1, CpG₁2, CpG₁4, CpG₁5.16, CpG₁7.18.19.20, CpG₂2.23, CpG₂4 and CpG₃1.32, were correlated with the occurrence of ESCC of Hazakh in Xinjiang Province (p<0.05). At the same time, the average methylation rate of the 10 CpG units in ESCC and NCAT were higher than NESE. But, the Comparison between ESCC and NCAT there were 2 CpG units among the 10 CpG units (CpG₁0, CpG₁1), which NCATs were higher than ESCC.2. Comparison between the methylation rate of miR-203₁5 and Clinical pathology characteristic:Comparing with gender, there were no CpG unit of miR-203₁5 had difference (p>0.05). Comparing with age, methylation status of CpG₂2.23 was correlated positively with it. Comparing with tumor position, methylation status of CpG₃1.32 had difference (p<0.05) and the average methylation rate was hypomere> midpiece> epimere. Comparing with tumor type, methylation status of CpG₂4 had difference (p<0.05). Comparing with differentiation degree, methylation status of CpG₁7.18.19.20 had difference (p<0.05) and the average methylation rate was moderately differentiated> well-differentiated> poorly differentiated. Comparing with metastasis of lymph node and TNM staging, there were no CpG unit of miR-203₁5 had difference (p>0.05). 3. Comparison between the methylation rate of miR-203₁5 and HPV16 infection:methylation status of CpG₁5.16, CpG₁7.18.19.20 had differences between HPV16-positive and HPV16-negative (p<0.05) and the average methylation rate was HPV16-positive> HPV16-negative.Conclusions:1.The methylation status of miR-203₁5 in ESCC and NCAT has a higher level than in NESE.2. There are 10 CpG units have been hypermethylated and it may be a molecular event in earlier Hazakh's ESCC.3. Hypermethylation of CpG₁5.16, CpG₁7.18.19.20 of miR-203 may correlate with the infection of HPV16 and participate the occurrence and development of Hazakh's ESCC together.