Akademik Veri Yönetim Sistemi
International Journal of Cancer Research and Prevention, cilt.8, sa.4, ss.575-588, 2015 (Scopus)
© 2015 Nova Science Publishers, Inc.Thyroid cancer is the most common cancer of the endocrine system. A majority of patients with thyroid cancer show a good prognosis after surgery and radioiodine ablation. However, the treatment of radio-resistant papillary type of undifferentiated anaplastic, and of medullary type thyroid cancers is still unsatisfactory. Therefore, there is a great need for better understanding of the thyroid carcinogenesis and improving the treatment of patients who are resistant to conventional therapy. Recent investigations in molecular field identified specific genetic and epigenetic alterations in different types of thyroid tumors. Thyroid carcinomas commonly contain one of the small number of recurrent genetic mutations. The differentiation and proliferation properties of thyroid cancer cells are also strongly influenced by epigenetic alterations, which are thought to be equally, if not more, important than mutational events in the formation and progression of human cancer. Epigenetic regulation is a phenomenon that refers to changes in the gene expression without altering the DNA sequence itself. Epigenetic modifications are acquired throughout life and are depend on environmental clues such as diet, lifestyle and toxin exposure. They are widely known for their reversibility. Epigenetic alterations are typically divided into three categories that are DNA methylation, histone post-translational modifications and deregulation of expression pattern of microRNAs. Epigenetically silenced tumor suppressor genes and activated oncogenes are the major targets of the researchs in cancer field. Encouraging preliminary results have been obtained with epigenetic treatment strategies in several forms of cancer. The epigenetic changes that occur in thyroid carcinomas (often in combination with genetic alterations) is expected to reveal more effective ways to treat tumors of this type that fail to respond to currently available treatment modalities. This chapter provides an inside look to genetic and epigenetic alterations recognized in thyroid cancer as target for new therapeutic approaches.