*Deciphering and Targeting Epigenetics in Cancer Metastasis DOI: http://dx.doi.org/10.5772/intechopen.106584*

metastatic cancer cells and the properties of metastatic tumor microenvironments are a great entry point to prevent cancer metastasis. As a result, several related drugs involved in cancer metastasis to treat cancer came into being. For instance, gefitinib and erlotinib are tyrosine kinase inhibitors (TKIs) that target activating epidermal growth factor receptor (EGFR) mutations and can improve overall survival by inhibiting metastasis in non-small cell lung cancer (NSCLC) [14, 15]. In general, cancer metastasizes to bone, liver, lung, and brain at an advanced stage, which is difficult for clinicians to destroy the secondary tumor. This is an urgent task and of great significance to patients. Thus, cancer biologists are working to deepen their understanding of epigenetic mechanisms in cancer metastasis to develop better therapy.

Although these drugs mentioned above contribute to clinical improvements in cancer patients, there exist some challenges. The first obstacle is that tumor heterogeneity, one of the characteristics of malignant tumors, which leads to the differences in immune characteristics, growth rate, aggressive ability, sensitivity to drugs, prognosis, and other phenotypic aspects after taking the same drugs. That means precision medicine and personalized medicine are the points of future medical development. Besides, the vast majority of genetic changes of epigenetics are inactivating mutations that are inherently difficult to treat, even though cancer biologists are designing drugs to interfere with adaptive mechanisms. Epigenetics provides a novel insight for researchers to improve the prognosis and survival of patients.

In this review, we summarize the procedures and routes of cancer metastasis as well as the roles of epigenetics including lncRNA, DNA methylation, and histone modifications in common metastases including bone, liver, lung, and brain, followed by discussing about potentials and limitations of epigenetics-related molecules in diagnosis, therapy, and prognosis.
