A new theory on cancer-inducing mechanism.
A new theory on cancer-inducing mechanism.
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关于癌症诱导机制的新理论。
DOI：
10.1038/bjc.1953.8
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发表时间：
1953-03
影响因子：
8.8
通讯作者：
NORDLING, C O
中科院分区：
文献类型：
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作者：
NORDLING, C O
最近在遗传学和病理学方面的研究表明，导致突变的因素与导致或促成癌症发展的因素之间存在惊人的一致性。自20世纪20年代以来，Bauer（1949）、Strong（1949）等人倡导的一个较为突出的理论声称，最初的癌细胞只不过是一个受某种基因突变影响的普通细胞。对这一理论的主要反对意见之一是，它不能解释癌症发生频率的年龄变化。对此，Bauer（1949）认为，突变细胞显然在很长一段时间内保持潜伏状态，直到新的特性变得明显，这种现象可以被诊断为癌症。Bauer发现，x射线癌的平均潜伏期为9年，石蜡癌为12年，苯胺癌为18年，水手癌（由太阳辐射引起）为40年。然而，肉瘤和白血病的早期发生并不符合潜伏期的概念。此外，假定潜伏期的长短取决于突变是由太阳射线引起的还是由x射线引起的，似乎有些不合理。此外，对于大多数类型的癌症，不同年龄的发病率是如此之高，以至于我们不得不考虑平均潜伏期为70年或更长，以便解释男性癌症死亡率的实际年龄频率曲线。这些事实仍然使该领域许多最有能力的权威难以毫无保留地接受突变理论。Dahlberg（1943）对年龄和癌症之间的关系提出了完全不同的解释。他认为恶性肿瘤随着年龄的增长越来越容易发展。这意味着，对于肿瘤细胞的发展，必须发生一定数量的细胞分裂，每一次分裂之间都有一定的时间间隔。所有关于慢性刺激促进细胞分裂的癌变影响的经验似乎都有力地支持了这一理论。于是问题就产生了，在细胞不同分裂之间的间隔期间，发生的过程的性质是什么。根据Timof6eff-Ressofsky、Delbruck和Zimmer（1935）在1934年提出的、薛定谔（1944）讨论过的理论，突变就是这样一个过程，它在每一个大的细胞群中不断地进行。根据这一理论，突变是由与构成温度的运动有关的正常分子碰撞以及来自其他种类的能量供应引起的，例如x射线。如果让足够多的细胞在足够长的时间内存活，其中一些细胞必然会发生基因突变。如果细胞繁殖——换句话说，如果有问题的组织生长或自我更新——突变的细胞就有可能大量繁殖。在这种情况下是可能的
RECENT research in genetics and pathology has shown an amazing consistency between the agents causing mutations and those causing-or contributing to the development of-cancer. One of the more prominent theories, which since the 1920's has been advocated by Bauer (1949), Strong (1949) and others, claims that the original cancerous cell is nothing but an ordinary cell affected by genetic mutation of some kind. One of the main objections to this theory has been that it does not explain the age variation of the cancer frequency. In reply, Bauer (1949) contends that the mutated cells apparently remain latent during a long period until the new qualities become evident and the phenomenon can be diag-nosed as cancer. Bauer has found this period of latency to average 9 years for X-ray cancer, 12 years for paraffin cancer, 18 years for aniline cancer and 40 years for seaman's cancer (caused by solar radiation). The early occurrence of sarcoma and of leukaemia, however, does not conform to the idea of a latent period. Moreover, it appears somewhat unreasonable to suppose that the length of the latency period would depend upon whether the mutation is caused by sun-rays or by X-rays. Writh most forms of carcinoma, furthermore, the frequency at different ages is such that wre are compelled to consider average latency periods of 70 years or more, inorder to explain the actual age frequency curve of cancer mortality in man. These facts still makeit difficult for many of the most competent authorities in the field to accept the mutation theory without reservations. Dahlberg (1943) has advanced a completely different explanation concerning the relationship between age and cancer. He expressed the opinion that malignant tumours develop increasingly easily with rising age. This implies that, for the development of tumourous cells, it is necessary for a certain number of cellular divisions to have taken place, between each of which there has been a certain period of time. All experience concerning the cancerous influence of chronic irritations promoting cellular divisions seems strongly to support this theory. The question then arises of thenature of the process taking place in the cellsduring the intervals betweentheir various divisions. According to the theory advanced in 1934 by Timof6eff-Ressofsky, Delbruck and Zimmer (1935) and discussed by Schroedinger (1944), mutations constitute sucha process, which goes on incessantly in every large group of cells. Mutations are caused, according to this theory, by the normal molecular collisions in connection with the movements constituting temperature, as well as by other kinds of energy supply originating from, for example, X-rays. If a large enough number of cells is allowed a sufficiently long period of time, gene mutations will necessarily occur in someof them. If the cells propagatein other words, if the tissue in question grows or renews itself-it is possible that the mutated cells will multiply in great number. In this case it is probable