Roles of histone methyl-modifying enzymes in development and progression of cancer

Retroviral insertional mutagenesis in mice is considered a powerful forward genetic strategy to identify disease genes involved in cancer. Our high-throughput screens led to frequent identification of the genes encoding the enzymes engaged in histone lysine methylation. Histone methylation can positively or negatively impact on gene transcription, and then fulfill important roles in developmental control and cell-fate decisions. A tremendous amount of progress has accelerated the characterization of histone methylations and the enzymes that regulate them. Deregulation of these histone methyl-modifying enzymes has been increasingly recognized as a hallmark of cancer in the last few years. However, in most cases, we have only limited understanding for the molecular mechanisms by which these enzymes contribute to cancer development and progression. In this review, we summarize the current knowledge regarding some of the best-validated examples of histone lysine methyltransferases and demethylases associated with oncogenesis and discuss their potential mechanisms of action.