Apoptosis and cell cycle

Apoptosis, a form of programmed cell death, is used to eliminate individual cells surrounded by normal cell population. It is a controlled way of cell death in which the cell actively participates by conducting precise, gene-regulated program of self-destruction, that is, cell 'suicide.' Active synthesis of macromolecules is necessary during this process. Death of individual cells is necessary to maintain a balance in living systems, so the process of apoptosis is continuously present in the body, which allows normal development, tissue homeostasis, and many other physiological processes. The molecular mechanisms that regulate apoptosis are functionally linked to other cellular mechanisms, such as control of the cell cycle, cell proliferation and differentiation, genomic stability and cellular metabolism. Damage to the DNA molecule, caused both spontaneously and under the influence of various chemical and physical agents, leads to the cell cycle arrest and activation of mechanisms that repair the damage. Depending on the type and extent of the damage, the cell either continues progression through the cell cycle, or activates the mechanisms that lead to apoptosis. Disturbances in the regulation of apoptosis and cell cycle present the molecular and biological basis of many diseases. Because of the importance of these processes during the development and progression of tumors, their use as biological markers is one of the main strategies in the formation of therapeutic approaches for the treatment of cancer