Department of Radiation Oncology, Second Affiliated Hospital of Dalian Medical University, Dalian, China.
Cancer Biother Radiopharm. 2012 Feb;27(1):56-64. doi: 10.1089/cbr.2011.1003. Epub 2012 Jan 16.
Elemene (1-methyl-1-vinyl-2,4-diisopropenyl-cyclohexane) is a naturally occurring compound that can be isolated from the traditional Chinese medicinal herb Curcuma wenyujin. β-elemene, its active component, has recently been demonstrated to enhance the radiosensitivity of human cancer cell lines in vitro and of one animal tumor in vivo. The underlying mechanism, however, is still unclear. In this study, we demonstrated for the first time that β-elemene significantly improves the radiosensitivity of A549 lung adenocarcinoma xenograft in vivo as measured by tumor regrowth delay experiments. Our results showed that β-elemene, at 45 mg/kg, significantly inhibited radiation-induced expression of survivin and hypoxia-inducible factor (HIF)-1 α proteins. Because HIF-1 α is known to regulate survivin transcription and acts as upstream regulator of survivin, it is possible that β-elemene regulates the transcription of survivin through HIF-1 α. Our study suggests that β-elemene is a promising drug to enhance tumor radioresponse, and survivin and HIF-1 α are novel targets of β-elemene.
榄香烯（1-甲基-1-乙烯基-2,4-二异丙烯基环己烷）是一种天然存在的化合物，可从传统中药莪术中分离出来。其活性成分β-榄香烯最近已被证明可在体外增强人癌细胞系和一种动物肿瘤的放射敏感性。然而，其潜在机制尚不清楚。在这项研究中，我们首次证明β-榄香烯可通过肿瘤生长延迟实验显著提高 A549 肺腺癌细胞异种移植模型的放射敏感性。我们的结果表明，β-榄香烯（45mg/kg）可显著抑制放射诱导的存活素和缺氧诱导因子（HIF）-1α蛋白的表达。因为已知 HIF-1α调节存活素转录，并作为存活素的上游调节剂，因此β-榄香烯可能通过 HIF-1α调节存活素的转录。我们的研究表明，β-榄香烯是一种有前途的增强肿瘤放射反应的药物，存活素和 HIF-1α是β-榄香烯的新靶点。
