β-榄香烯通过上调P53蛋白表达促进外泌体释放来对抗人类肺癌。

β-Elemene against human lung cancer via up-regulation of P53 protein expression to promote the release of exosome.

作者信息

Li Jianying, Liu An, Wang Yili

机构信息

Department of Respiratory Disease, Affiliated Xi'an Central Hospital, Medical school of Xi'an Jiaotong University, Xi'an, Shaanxi Province 710003, China; Center of Cancer Research, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710003, China.

Department of Surgery, Affiliated Xi'an Central Hospital, Medical school of Xi'an Jiaotong University, Xi'an, Shaanxi Province, 710003, China.

出版信息

Lung Cancer. 2014 Nov;86(2):144-50. doi: 10.1016/j.lungcan.2014.08.015. Epub 2014 Aug 29.

DOI:10.1016/j.lungcan.2014.08.015

PMID:25204604

Abstract

BACKGROUND

β-Elemene, a novel antitumor plant drug extracted from the traditional Chinese medicinal herb Zedoary, has been shown to be effective against a wide variety of tumors. Recent studies have indicated that β-elemene can inhibit the growth of lung cancer cells; however, the exact mechanism of β-element's action in lung cancer remains largely unknown. In the present study, the antitumor effect of β-elemene on human lung cancer cells and the mechanism involved has been investigated.

METHODS

The inhibitory effects of β-elemene on cell growth were measured by Trypan Blue exclusion and MTT assay. Flow cytometric analysis was used to detect the cells' apoptotic rate. The expression of P53 mRNA and protein were measured by RT-PCR and Western blot analysis, respectively. Exosomes were isolated by differential centrifugation steps and analyzed by electron microscopy and western blotting. P53 knockdown cells were established through transfection with P53 siRNA. To investigate the effect of β-elemene on the tumor growth in vivo, a Xenograft nude mouse model was established by injecting the A549 cells into the back of a BABL/c nude mouse.

RESULTS

β-Elemene markedly inhibited growth and induced apoptosis in lung cancer cells. The levels of the anti-apoptotic genes Bcl-2 and Bcl-xl in A549 cells decreased, while expression of P53 and production of exosomes increased after β-elemene treatment. Further siRNA studies suggested that the effect of β-elemene on A549 cells is dependent on P53 expression. Exosomes derived from A549 cultured with a human lung cancer cell line exhibited decreased tumor cell proliferation. The in vivo study demonstrated that β-elemene inhibited tumor growth, and up-regulated the expression of P53 and the release of exosome.

CONCLUSION

Our results demonstrated β-elemene acts on lung cancer cells in a P53 dependent manner and exosomes are involved in the regulation of cell proliferation.

摘要

背景

β-榄香烯是一种从传统中药材莪术中提取的新型抗肿瘤植物药，已被证明对多种肿瘤有效。最近的研究表明，β-榄香烯可抑制肺癌细胞的生长；然而，β-榄香烯在肺癌中的具体作用机制仍不清楚。在本研究中，我们研究了β-榄香烯对人肺癌细胞的抗肿瘤作用及其相关机制。

方法

采用台盼蓝排斥法和MTT法检测β-榄香烯对细胞生长的抑制作用。采用流式细胞术分析检测细胞凋亡率。分别用RT-PCR和Western blot分析检测P53 mRNA和蛋白的表达。通过差速离心步骤分离外泌体，并通过电子显微镜和蛋白质印迹法进行分析。通过转染P53 siRNA建立P53基因敲低细胞。为了研究β-榄香烯对体内肿瘤生长的影响，将A549细胞注射到BABL/c裸鼠背部建立异种移植裸鼠模型。

结果

β-榄香烯显著抑制肺癌细胞的生长并诱导其凋亡。β-榄香烯处理后，A549细胞中抗凋亡基因Bcl-2和Bcl-xl的水平降低，而P53的表达和外泌体的产生增加。进一步的siRNA研究表明，β-榄香烯对A549细胞的作用依赖于P53的表达。用人肺癌细胞系培养的A549来源的外泌体显示肿瘤细胞增殖减少。体内研究表明，β-榄香烯抑制肿瘤生长，并上调P53的表达和外泌体的释放。