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arXiv · 1505.01375

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

Abstract

Development of a tumor is known to be a result of accumulation of DNA changes in somatic cells. However, the processes of how DNA changes are produced and how they accumulate in somatic cells are not clear. DNA changes include two types: point DNA mutations and chromosome changes. However, point DNA mutations (DNA mutations) are the main type of DNA changes 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 the process of aging of a genome DNA. Repeated cell injuries and repeated cell regenerations are the two preconditions for tumor-development. For cancer prevention, a moderate and flexible living style is advised.

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Jicun Wang-Michelitsch, Thomas M. Michelitsch. 2015-05-06. Cell transformation in tumor-development: a result of accumulation of Misrepairs of DNA through many generations of cells. https://arxiv.org/abs/1505.01375

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