The inability of cancer drugs to destroy metastatic tumors is the major reason why cancer therapy fails. Even though the process of drug design has become exceedingly sophisticated in recent years, there is not a single drug available that is 100% effective against metastatic cancer. Resistance to treatment with anticancer drugs results from a variety of factors including individual variations in patients and somatic/genetic differences in tumors, even those from tissue of origin. Although it is a generally accepted fact that the majority of cancers arise from a single precursor cell, it is naive to consider that tumor is a collection of genetically identical cells. Genetic instability and accumulation of mutations are important hallmarks of cancer cells. This means that dividing cancer cells are able to acquire genetic and epigenetic changes that will favor their malignant phenotype. In view of this, it is fair to say that the cells in a given tumor may be similar but not identical. Therefore, when treated with a drug, the sensitive cells in a tumor succumb to the toxic effects of the drug, and resistant cells continue to survive and multiply. The tumor, which re-grows from these residual resistant cells, is not sensitive to the original drug.
具體描述
讀後感
評分
評分
評分
評分
用戶評價
相關圖書
本站所有內容均為互聯網搜索引擎提供的公開搜索信息，本站不存儲任何數據與內容，任何內容與數據均與本站無關，如有需要請聯繫相關搜索引擎包括但不限於百度，google,bing,sogou 等
© 2025 book.quotespace.org All Rights Reserved. 小美書屋 版权所有