Open AccessHypomethylation of the XIST Gene Promoter in Prostate Cancer
Author(s) -
Thilo Laner,
Wolfgang A. Schulz,
Rainer Engers,
Mirko Müller,
Andrea R. Florl
Publication year - 2005
Publication title -
oncology research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.267
H-Index - 57
eISSN - 1555-3906
pISSN - 0965-0407
DOI - 10.3727/096504005776404607
Subject(s) - xist , dna methylation , biology , prostate cancer , prostate , cancer research , methylation , gene , cancer , chromoplexy , bisulfite sequencing , pca3 , promoter , gene expression , genetics , microbiology and biotechnology , x chromosome , x inactivation
In a process denoted "global hypomethylation" repetitive DNA sequences like LINE-1 retrotransposons become hypomethylated in human cancers, including a subset of prostate carcinomas. It is less well known to what extent single-copy sequences are affected by this phenomenon. Therefore, we have analyzed methylation and expression of the XIST gene by bisulfite sequencing and real-time RT-PCR. The promoter of this single-copy gene is strongly methylated in normal male cells, including leukocytes and normal prostate. In prostate cancer tissues and particularly in cell lines, partial hypomethylation was observed paralleling that of LINE-1 sequences. Weak XIST expression was found in normal prostate tissues, but none in leukocytes. Only slight increases in expression of this gene were found in cancer tissues and cell lines. Our data suggest that hypomethylation in prostate cancer is indeed "global," affecting repeat and unique sequences in parallel. Detection of partially hypomethylated XIST alleles in prostate cancer tissues might be useful for the identification of cases with pronounced hypomethylation, which tend to be more aggressive.