Gallagher C H, Greenoak G E, Reeve V E, Canfield P J, Baker R S, Bonin A M
Aust J Exp Biol Med Sci. 1984 Oct;62 ( Pt 5):577-88. doi: 10.1038/icb.1984.55.
The mutagenicity of some samples of a commonly used sunscreen, 2-ethylhexyl-p-methoxycinnamate (2-EHMC), led to these studies of its potential carcinogenicity in the HRA/Skh hairless mouse. In a daily treatment regime, repeated for 9 weeks, groups of mice were painted on the dorsum with 2-EHMC, and were then exposed to low doses of one of two artificial ultraviolet (UV) light sources. Mice were also treated with UV alone and with 2-EHMC alone. The accumulated UV exposure alone produced tumours in 40-100% of mice. However, 2-EHMC-treated mice were protected. Subsequent treatment of the 2-EHMC-protected mice, and mice previously treated with 2-EHMC alone, with the tumour promoter, croton oil, produced tumours on a significant number of animals. We conclude that 2-EHMC protects from UV tumorigenesis in the absence of a tumour promoter. However, although tumours appeared on only 4 out of 160 2-EHMC-treated mice exposed to UV, the carcinogenic process had been initiated in others, as application of the tumour promoter, croton oil, produced tumours. Statistical analysis of the incidence of promoted tumours inferred that prior irradiation with UV may not have been implicated. Therefore, 2-EHMC itself may initiate tumours in this strain of hairless mouse.
一种常用防晒剂对甲氧基肉桂酸 2 - 乙基己酯（2 - EHMC）某些样品的致突变性引发了对其在 HRA/Skh 无毛小鼠中潜在致癌性的这些研究。在为期 9 周的每日处理方案中，给几组小鼠背部涂抹 2 - EHMC，然后使其暴露于两种人工紫外线（UV）光源之一的低剂量照射下。还分别对小鼠单独进行紫外线处理以及单独使用 2 - EHMC 处理。仅累积紫外线照射使 40% - 100%的小鼠产生肿瘤。然而，经 2 - EHMC 处理的小鼠受到了保护。随后对经 2 - EHMC 保护的小鼠以及之前仅用 2 - EHMC 处理过的小鼠，使用肿瘤促进剂巴豆油进行处理，导致大量动物产生肿瘤。我们得出结论，在没有肿瘤促进剂的情况下，2 - EHMC 可预防紫外线诱导的肿瘤发生。然而，尽管在 160 只经 2 - EHMC 处理并暴露于紫外线的小鼠中只有 4 只出现肿瘤，但致癌过程在其他小鼠中已经启动，因为使用肿瘤促进剂巴豆油产生了肿瘤。对促进性肿瘤发生率的统计分析推断，先前的紫外线照射可能与此无关。因此，2 - EHMC 本身可能在这种无毛小鼠品系中引发肿瘤。
