Cell transformation in tumor-development: a result of accumulation of Misrepairs of DNA through many generations of cells

Development of a tumor is known to be a result of accumulation of DNA mutations in somatic cells. However, the processes of how DNA mutations are produced and how DNA mutations accumulate in somatic cells are not completely known. There are several types of DNA mutations; however point mutations are the main type of mutations that can remain and accumulate in cells. Severe DNA injuries are the causes for DNA mutations; however Misrepair of DNA is an essential process for transforming a DNA injury into a “survivable and inheritable” DNA mutation. In somatic cells, Misrepair of DNA is the main source of DNA mutations. Since the surviving chance of a cell by Misrepair of DNA is low, accumulation of DNA mutations can take place only possibly in the cells that can proliferate. Tumors can only develop in the tissues that are regenerable. The accumulation of Misrepairs of DNA needs to proceed in many generations of cells, and cell transformation from a normal cell into a tumor cell is a slow and long process. However, once a cell is transformed, especially when it is malignantly transformed, the deficiency of DNA repair and the rapid cell proliferation will accelerate the accumulation of DNA mutations. The process of accumulation of DNA mutations is actually a process of aging of a genome DNA. Repeated injuries and repeated regenerations of cells are the two preconditions for tumor-development. For cancer prevention, a moderate and flexible living style is beneficial.