Baramiya M G
Department of Histology, Cytology and Embryology, Saratov State Medical University, Saratov, Russia.
Gerontology. 2000 Nov-Dec;46(6):328-32. doi: 10.1159/000022186.
The mechanisms of the development of cancer in old age and also the mechanisms of aging are not well understood. This paper tries to interpret consequences of malignant tissue transformation from the viewpoint of aging, or in other words, from an insufficient cell adaptation to the needs of repair and proliferation.
A hypothesis is presented that a unified but quite opposite at different stages of ontogenesis mechanism is the basis of atypical growth and embryonic development. In the beginning of a malignant dedifferentiation is an insufficiency of an effective self-renovation and disturbed preservation of its adaptation capability. The suppression of regenerating cell proliferation is the primary event of the development of a dedifferentiated tissue growth. The transformation of normal cells into tumor cells is an adaptive reaction in reply to a shortage of self-regeneration capability and repair. Allowing for the process of rebirth, i.e. the complete restoration of tissues leading to the restrain of senescence proceeds by the type of embryonic growth of tissues, the possibility to use the potential of transformed cells for restraining senescence is proposed. The latter will permit to direct the process of transformation to an integrated growth channel, to prevent the clinical phenomenon of malignancy, and use the potential of transformed cells for realization of the self-renovation program and program of unlimited life duration of the whole organism.
By a stimulation or compensation of the age-induced shortage of cell metabolism, two effects can be expected: prevention of cancer and retardation of aging.
老年癌症发生的机制以及衰老机制尚未完全明了。本文试图从衰老的角度,或者换句话说,从细胞对修复和增殖需求的适应不足的角度来解释恶性组织转化的后果。
提出一种假说,即一种在个体发育不同阶段统一但又截然相反的机制是异常生长和胚胎发育的基础。恶性去分化开始时,有效的自我更新不足且其适应能力的维持受到干扰。再生细胞增殖的抑制是去分化组织生长发展的首要事件。正常细胞向肿瘤细胞的转化是对自我再生能力和修复不足的一种适应性反应。考虑到重生过程,即组织的完全恢复从而导致衰老的抑制是通过组织的胚胎生长类型进行的,因此提出利用转化细胞的潜能来抑制衰老的可能性。后者将允许将转化过程引导至整合生长通道,防止恶性肿瘤的临床现象,并利用转化细胞的潜能来实现自我更新程序和整个生物体无限寿命的程序。
通过刺激或补偿年龄引起的细胞代谢不足,可以预期两种效果:预防癌症和延缓衰老。