Association between Long Interspersed Nuclear Element-1 Methylation and Relative Telomere Length in Wilms Tumor

Chin Med J (Engl). 2015 Nov 20;128(22):3055-61. doi: 10.4103/0366-6999.169071.


Background: DNA hypomethylation of long interspersed nuclear elements-1 (LINEs-1) occurs during carcinogenesis, whereas information addressing LINE-1 methylation in Wilms tumor (WT) is limited. The main purpose of our study was to quantify LINE-1 methylation levels and evaluate their relationship with relative telomere length (TL) in WT.

Methods: We investigated LINE-1 methylation and relative TL using bisulfite-polymerase chain reaction (PCR) pyrosequencing and quantitative PCR, respectively, in 20 WT tissues, 10 normal kidney tissues and a WT cell line. Significant changes were analyzed by t-tests.

Results: LINE-1 methylation levels were significantly lower (P < 0.05) and relative TLs were significantly shorter (P < 0.05) in WT compared with normal kidney. There was a significant positive relationship between LINE-1 methylation and relative TL in WT (r = 0.671, P = 0.001). LINE-1 Methylation levels were significantly associated with global DNA methylation (r = 0.332, P < 0.01). In addition, relative TL was shortened and LINE-1 methylation was decreased in a WT cell line treated with the hypomethylating agent 5-aza-2'-deoxycytidine compared with untreated WT cell line.

Conclusion: These results suggest that LINE-1 hypomethylation is common and may be linked to telomere shortening in WT.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Child
  • Child, Preschool
  • DNA Methylation / genetics
  • Female
  • Humans
  • Long Interspersed Nucleotide Elements / genetics*
  • Male
  • Polymerase Chain Reaction
  • Telomere / genetics*
  • Wilms Tumor / genetics*