Just another brick in the wall: unravelling the epigenetic mechanism underlying tumour initiation of testicular germ cell cancer

Abstract

Clarifying the genomic basis of human diseases and its many breakthroughs in cancer medicine has distracted our view from the importance and complexity of epigenomic information. A wall of dogmas awaiting their destruction was built: DNA methylation was proposed to occur passively but subsequently active DNA demethylation was discovered (Cedar, 1988). Histone methylation was thought to be irreversible until the first histone methylase, lysine-specific demethylase 1, was discovered and shown to provide essential cues for transcriptional regulation (Shi et al, 2004; Metzger et al, 2005). Subsequently, understanding the epigenome and its key writer enzymes, methylases and demethylases, provided important insights into pathomechanisms of aging, cancer and inflammation. The current study by Kristensen et al (2014) now closes another gap by providing evidence for an epigenetic mechanism driving intratubular germ cell neoplasia unclassified (ITGCNU), the precursor lesion for invasive testicular germ cell cancer (TGCC).