Correlation between abnormal methylation of IGF-2 exon 9 and IGF-2 gene expression

Object To investigate the correlation of IGF-2 exon 9 CpG island methylation and the expression of IGF-2,and further explore the mechanism of Wilms tumor. Methods The IGF-2 exon 9 methylation status and IGF2 gene expression in 42 cases of Wilms tumor and corresponding normal tissues were detected by using methylation-sensitive restriction enzyme PCR and allele-specific IGF2 gene expression analysis.Results IGF-2 exon 9 methylation rate was 15% in W ilms tumor group, and 97% in normal tissue group. The difference was significant (P \u003c 0.01), and the difference in pathological type was also significantly different (P \u003c 0.01). Exon 9 unmethylated tissues showing biallelic expressions of IGF-2 were significantly higher than that of methylated tissues (P \u003c 0.05). Conclusion IGF-2 exon 9 unmethylation may be the cause of biallelic expression of IGF, which contritues to tumorigenesis in Wilms tumor.\r\n\r\nKey words: \r\nWilms tumors;  Insulin-like growth factor Ⅱ;  DNA methylation