Kou Yanni, Wang Shujie, Ma Yanjie, Zhang Ning, Zhang Zixiong, Liu Qian, Mao Yang, Zhou Rui, Yi Dongrong, Ma Ling, Zhang Yongxin, Li Quanjie, Wang Jing, Wang Jinhui, Zhou Xile, He Chunnian, Ding Jiwei, Cen Shan, Li Xiaoyu
Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
Front Pharmacol. 2022 May 24;13:881938. doi: 10.3389/fphar.2022.881938. eCollection 2022.
Long interspersed nuclear element 1 (LINE-1) is a dominant autonomous retrotransposon in human genomes which plays a role in affecting the structure and function of somatic genomes, resulting in human disorders including genetic disease and cancer. LINE-1 encoded ORF1p protein which possesses RNA-binding and nucleic acid chaperone activity, and interacts with LINE-1 RNA to form a ribonucleoprotein particle (RNP). ORF1p can be detected in many kinds of tumors and its overexpression has been regarded as a hallmark of histologically aggressive cancers. In this study, we developed an In-Cell Western (ICW) assay in T47D cells to screen the compounds which can decrease the expression of ORF1p. Using this assay, we screened 1,947 compounds from the natural products library of Target Mol and Selleckchem, among which three compounds, Hydroxyprogesterone, 2,2':5',2″-Terthiophene and Ethynyl estradiol displayed potency in diminishing LINE-1 ORF1p expression level. Further mechanistic studies indicated the compounds act by affecting LINE-1 RNA transcription. Notably, we demonstrated that the compounds have an inhibitory effect on the proliferation of several lung and breast cancer cell lines. Taken together, we established a high throughput screening system for ORF1p expression inhibitors and the identified compounds provide some clues to the development of a novel anti-tumor therapeutic strategy by targeting ORF1p.
长散在核元件1（LINE-1）是人类基因组中占主导地位的自主逆转座子，在影响体细胞基因组的结构和功能方面发挥作用，导致包括遗传疾病和癌症在内的人类疾病。LINE-1编码的ORF1p蛋白具有RNA结合和核酸伴侣活性，并与LINE-1 RNA相互作用形成核糖核蛋白颗粒（RNP）。ORF1p可在多种肿瘤中检测到，其过表达被视为组织学上侵袭性癌症的标志。在本研究中，我们在T47D细胞中开发了一种细胞内western（ICW）检测方法，以筛选能够降低ORF1p表达的化合物。利用该检测方法，我们从Target Mol和Selleckchem的天然产物库中筛选了1947种化合物，其中三种化合物，羟孕酮、2,2':5',2″-三联噻吩和乙炔雌二醇在降低LINE-1 ORF1p表达水平方面表现出效力。进一步的机制研究表明，这些化合物通过影响LINE-1 RNA转录发挥作用。值得注意的是，我们证明了这些化合物对几种肺癌和乳腺癌细胞系的增殖具有抑制作用。综上所述，我们建立了一种针对ORF1p表达抑制剂的高通量筛选系统，所鉴定的化合物为开发以ORF1p为靶点的新型抗肿瘤治疗策略提供了一些线索。
