Notaro Antonietta, Sabella Selenia, Pellerito Ornella, Di Fiore Riccardo, De Blasio Anna, Vento Renza, Calvaruso Giuseppe, Giuliano Michela
1. Laboratory of Biochemistry, Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Polyclinic, Palermo, Italy.
2. Laboratory of Cellular and Developmental Genetics, Department of Molecular Biology, Medical Biochemistry and Pathology, Faculty of Medicine, Université Laval, Québec, Canada.
Int J Biol Sci. 2014 Apr 8;10(5):466-78. doi: 10.7150/ijbs.8337. eCollection 2014.
The synthetic cannabinoid WIN 55,212-2 is a potent cannabinoid receptor agonist with anticancer potential. Experiments were performed to determine the effects of WIN on proliferation, cell cycle distribution, and programmed cell death in human osteosarcoma MG63 and Saos-2 cells. Results show that WIN induced G2/M cell cycle arrest, which was associated with the induction of the main markers of ER stress (GRP78, CHOP and TRB3). In treated cells we also observed the conversion of the cytosolic form of the autophagosome marker LC3-I into LC3-II (the lipidated form located on the autophagosome membrane) and the enhanced incorporation of monodansylcadaverine and acridine orange, two markers of the autophagic compartments such as autolysosomes. WIN also induced morphological effects in MG63 cells consisting in an increase in cell size and a marked cytoplasmic vacuolization. However, WIN effects were not associated with a canonical apoptotic pathway, as demonstrated by the absence of specific features, and only the addition of TRAIL to WIN-treated cells led to apoptotic death probably mediated by up-regulation of the tumor suppressor factor PAR-4, whose levels increased after WIN treatment, and by the translocation of GRP78 on cell surface.
合成大麻素WIN 55,212-2是一种具有抗癌潜力的强效大麻素受体激动剂。进行了实验以确定WIN对人骨肉瘤MG63和Saos-2细胞增殖、细胞周期分布和程序性细胞死亡的影响。结果表明，WIN诱导G2/M期细胞周期阻滞，这与内质网应激的主要标志物（GRP78、CHOP和TRB3）的诱导有关。在处理过的细胞中，我们还观察到自噬体标志物LC3-I的胞质形式转化为LC3-II（位于自噬体膜上的脂化形式），以及单丹磺酰尸胺和吖啶橙（自噬隔室如自溶酶体的两种标志物）的掺入增加。WIN还在MG63细胞中诱导了形态学效应，表现为细胞大小增加和明显的细胞质空泡化。然而，WIN的作用与经典的凋亡途径无关，这通过缺乏特定特征得以证明，并且只有在WIN处理的细胞中添加TRAIL才导致凋亡死亡，这可能是由肿瘤抑制因子PAR-4的上调介导的，PAR-4的水平在WIN处理后增加，并且通过GRP78在细胞表面的转位。
