辐射暴露引起癌症的想法需要重新审视的原因
1Department of Molecular Biosciences, Radiation Effects Research Foundation, Hiroshima, Japan.
International journal of radiation biology
|April 22, 2024
概括
辐射暴露可能通过诱导早期发病而导致癌症,不一定通过增加癌症发病率. 这挑战了长期以来关于辐射致癌的突变诱导理论.
科学领域:
- 辐射致癌的发生是放射性致癌.
- 癌症流行病学癌症流行病学
- 突变理论是关于突变的.
背景情况:
- 传统观点认为,辐射通过致癌突变引起癌症.
- 最近的观察挑战了这一点,表明现有癌症的早期发病.
研究的目的:
- 批判性地审查支持辐射致癌的突变诱导理论的研究.
- 评估实验设计和数据分析在辐射致癌研究中的有效性.
主要方法:
- 对已发表的关于辐射致癌性的论文进行批判性审查.
- 分析实验设计,包括观察持续时间和年龄调整.
- 检查与癌症发病有关的剂量反应数据.
主要成果:
- 确定了误导性的实验设计:研究提前结束和不适当的年龄调整.
- 年龄调整,旨在弥补辐射缩短生命的影响,掩盖了早期癌症发病.
- 用终身观察对老鼠进行的实验表明,由于辐射而导致的瘤死亡率没有显著增加.
结论:
- 辐射暴露可能会导致自发性癌症的早期发病,而不是增加癌症比例.
- 人类流行病学数据支持早期发病假设.
- 早期发病模式适用于随年龄增长的恶性瘤,但不适用于儿童白血病或甲状腺癌等短延迟疾病.
相关概念视频
Biological Effects of Radiation
15.4K
All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. The most serious biological damage results when these radioactive emissions fragment or ionize molecules. For example, α and β particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. When these particles strike and penetrate matter, they...
15.4K
Mutations
37.1K
Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations can be characterized in a number of different ways: whether and how they alter the amino acid sequence of the protein, whether they occur over a small or large area of DNA, and whether they occur in somatic cells or germline cells.
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
37.1K
Cancer Prevention
6.2K
Several factors can increase the risk of cancer in an individual. About 50% of cancer cases can be prevented by adopting a healthy lifestyle, regular exercise, eating healthy, and following a modest cancer prevention diet. Epidemiological studies have consistently shown that populations with vegetable and fruit-rich diets have reduced the incidence of cancer. On the other hand, populations who have a diet rich in animal fat, red meat, junk food, or high calories are predisposed to cancer.
Some...
Some...
6.2K
Mutagenicity and Carcinogenicity
1.3K
Mutagenicity and carcinogenicity refer to the ability of drugs to cause genetic defects and induce cancer, respectively. The International Agency for Research on Cancer (IARC) classifies agents into four groups based on their carcinogenic potential. Group 1 agents are known human carcinogens; group 2A agents are probably carcinogenic to humans; group 3 agents lack data to support their role in carcinogenesis; and group 4 includes agents for which data support that they are not likely to be...
1.3K
Skin Cancer
4.1K
Skin cancer is a type of cancer that occurs when there is an abnormal growth of skin cells, usually triggered by damage to the DNA within the skin cells. It is primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Skin cancer is the most common type of cancer worldwide, and its incidence continues to rise.
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
Basal Cell Carcinoma (BCC): BCC is the most common type of skin cancer, accounting for about 80% of cases. It typically develops in...
4.1K
Mechanisms of Retrovirus-induced Cancers
5.1K
Retroviruses are RNA viruses that have been shown to cause cancers in diverse species, including chickens, mice, cats, and monkeys. The RNA genomes of these viruses are first reverse-transcribed into single and then double-stranded DNA (dsDNA) copies. This dsDNA called proviral DNA then integrates into the host genome. Subsequently, the host cell transcribes the proviral DNA in concert with the chromosomal DNA. This leads to the production of viral RNA and proteins that assemble at the host...
5.1K


