Shandong Provincial Key Laboratory of Radiation Oncology, Shandong Cancer Hospital affiliated to Shandong University, Shandong Academy of Medical Sciences, 440 Ji-Yan Road, Jinan, 250117, Shandong Province, People's Republic of China.
Key Laboratory of Animal Resistance Research, College of Life Science, Shandong Normal University, 88 East Wenhua Road, Jinan, Shandong, People's Republic of China.
J Exp Clin Cancer Res. 2019 Jun 7;38(1):239. doi: 10.1186/s13046-019-1249-1.
Temozolomide-perillyl alcohol conjugate (NEO212), a novel temozolomide (TMZ) analog, was previously reported to exert its anti-cancer effect in non-small cell lung cancer (NSCLC), and human nasopharyngeal carcinoma (NPC), etc.. In the current study, we intend to illuminate the potential anticancer property and the underly mechanisms of NEO212 in ovarian cancer cells.
The cytotoxicity of NEO212 was detected by MTT, colony formation analysis and xenograft model. The proteins involved in cell proliferation, DNA damage, autophagy and lysosomal function were detected by western blots; mitochondria, lysosome and autophagosome were visualized by TEM and/or immunofluorescence; Apoptosis, cell cycle analysis and mitochondrial transmembrane potential were detected by flow cytometry. TFEB translocation was detected by immunofluorescence and western blot.
NEO212 has the potential anticancer property in ovarian cancer cells, as evidence from cell proliferation inhibition, G/M arrest, DNA damage, xenograft, mitochondrial dysfunction and apoptosis. Importantly, we observed that although it induced significant accumulation of autophagosomes, NEO212 quenched GFP-LC3 degradation, down-regulated a series of lysosome related gene expression and blocked the autophagic flux, which significantly facilitated it induced apoptosis and was largely because it inhibited the nuclear translocation of transcription factor EB (EB).
NEO212 inhibited TFEB translocation, and impaired the lysosomal function, implying NEO212 might avoid from autophagy mediated chemo-resistance, thus proposing NEO212 as a potential therapeutic candidate for ovarian cancer.
替莫唑胺-叶绿醇缀合物（NEO212）是一种新型替莫唑胺（TMZ）类似物，先前已报道其在非小细胞肺癌（NSCLC）和人鼻咽癌（NPC）等中的抗癌作用。在本研究中，我们旨在阐明 NEO212 在卵巢癌细胞中的潜在抗癌特性和作用机制。
通过 MTT、集落形成分析和异种移植模型检测 NEO212 的细胞毒性。通过 Western blot 检测参与细胞增殖、DNA 损伤、自噬和溶酶体功能的蛋白质；通过 TEM 和/或免疫荧光观察线粒体、溶酶体和自噬体；通过流式细胞术检测细胞凋亡、细胞周期分析和线粒体膜电位。通过免疫荧光和 Western blot 检测 TFEB 易位。
NEO212 对卵巢癌细胞具有潜在的抗癌特性，表现在细胞增殖抑制、G/M 期阻滞、DNA 损伤、异种移植、线粒体功能障碍和凋亡。重要的是，我们观察到，尽管它诱导了大量自噬体的积累，但 NEO212 抑制了 GFP-LC3 的降解，下调了一系列溶酶体相关基因的表达并阻断了自噬流，这显著促进了它诱导的细胞凋亡，主要是因为它抑制了转录因子 EB（EB）的核易位。
NEO212 抑制了 TFEB 的易位，破坏了溶酶体功能，这表明 NEO212 可能避免了自噬介导的化疗耐药，因此提出 NEO212 可能是卵巢癌的潜在治疗候选物。
