Department of Hematology, Affiliated Hospital of Chengde Medical University, Chengde, Hebei, China.
Department of Hematology, Affiliated Hospital of Chengde Medical University, Chengde, Hebei, China.
Biomed Pharmacother. 2020 Jul;127:110167. doi: 10.1016/j.biopha.2020.110167. Epub 2020 Apr 25.
To investigate the effects of valproic acid (VPA) on autophagic flux in multiple myeloma (MM) cells.
Cell proliferation was assayed by the Cell Counting Kit-8 assay. The qRT-PCR was used to measure the expressions of LC3-II at mRNA level. Autophagic flux was measured by LC3-II turnover using western blot analysis and flow cytometry using the fluorescent dye Cyto-ID. An assay using the RFP-GFP-LC3 tandem construct was performed to monitor autophagic flux. Cell proliferation assay showed that VPA could inhibit the proliferation of MM cells and the inhibitory effects were enhanced with the extension of time. The qRT-PCR and western blot showed that the expression level of LC3-II in the VPA plus CQ group was significantly higher than that in CQ group. Cyto-ID autophagy test showed that the intracellular average fluorescence intensity in VPA plus CQ group was significantly higher than that in control and VPA group (all p < 0.001). The results of RFP-GFP-LC3 tandem construct showed that the numbers of yellow puncta and red puncta in VPA group was higher than that in control group.
VPA could inhibit the proliferation of MM cells and the inhibitory effects were enhanced with the extension of time. VPA could enhance autophagic flux in MM cells, and the increase of autophagosomes was caused by autophagy enhancement rather than inhibition. These findings provided rationale for the treatment of MM with VPA.
研究丙戊酸（VPA）对多发性骨髓瘤（MM）细胞自噬流的影响。
用细胞计数试剂盒-8 法检测细胞增殖。用 qRT-PCR 法测量 LC3-II 在 mRNA 水平的表达。用 LC3-II 周转的 Western blot 分析和流式细胞术使用荧光染料 Cyto-ID 来测量自噬流。使用 RFP-GFP-LC3 串联构建体进行测定以监测自噬流。细胞增殖试验表明，VPA 可抑制 MM 细胞的增殖，且随着时间的延长，抑制作用增强。qRT-PCR 和 Western blot 表明，VPA+CQ 组的 LC3-II 表达水平明显高于 CQ 组。Cyto-ID 自噬试验表明，VPA+CQ 组的细胞内平均荧光强度明显高于对照组和 VPA 组（均 p<0.001）。RFP-GFP-LC3 串联构建体的结果表明，VPA 组的黄色斑点和红色斑点数量高于对照组。
VPA 可抑制 MM 细胞的增殖，且随着时间的延长，抑制作用增强。VPA 可增强 MM 细胞的自噬流，自噬体的增加是由于自噬增强而不是抑制所致。这些发现为 VPA 治疗 MM 提供了依据。
