Epithelial To Mesenchymal Transition and Irradiation

Despite the fact that radiotherapy is one of the main therapeutic modalities in cancer treatment, some studies suggest that fractionated radiotherapy might confer radioresistance through epithelial‐mesenchymal transition (EMT), and its efficacy is restricted by this process. The EMT is a biological process that allows polarized epithelial cells to undergo multiple biochemical changes, and enable them to exhibit mesenchymal cells phenotype. This process is associated with downregulation of epithelial cell surface markers such as E-cadherin and upregulation of mesenchymal cell surface markers such as N-cadherin. The cells undergo the EMT process lose their adhesiveness to basement membrane, defined epithelial morphology and cell-cell connections. eventually this process leads to tumor recurrence and metastasis. The EMT process is classified into three different subtypes: the first one is associated with implantation and embryo formation; the second type occurs during wound healing; tissue regeneration and organ fibrosis, and the third type takes place in epithelial cancer cells that implies cancer progression and metastasis. Different stimulants such as hypoxia, growth factor signaling, tumor-stromal cell interactions and ionizing radiation can trigger the EMT process. Ionizing radiation could trigger different signaling pathways associated with EMT, and cells become resistant to radiation by this way. Different types of natural materials could inhibit the EMT process by various ways. These components can be used as proper partners in radiotherapy, chemotherapy and enhance treatment efficacy. For example, Genistein is a small, biologically active flavonoid that poses EMT inhibitory effects in different cell lines.

کلیدواژه ها:

Epithelial to Mesenchymal Transition (EMT) ، Ionizing Radiation ، ، Radioresistance