Department of Environmental and Occupational Health, Liaoning Provincial Key Laboratory of Arsenic Biological Effect and Poisoning, School of Public Health, China Medical University, No. 77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning Province 110122, P. R. China.
Metallomics. 2018 Mar 1;10(3):486-495. doi: 10.1039/c7mt00305f. Epub 2018 Mar 12.
To understand the direct link between Cyclin D1, and nuclear factor of activated T cells 2 (NFAT2) and nuclear factor (NF)-κB in arsenic-treated bladder cells, as well as the association between MAPK and NFAT signaling, we determined whether or not the Ca/NFAT pathway is activated in an arsenic-treated normal urothelial cell line and determined the roles of NFAT and NF-κB signals in the regulation of Cyclin D1 expression. The SV-40 immortalized human uroepithelial cell line, SV-HUC-1, was treated with NaAsO for 24 h (0, 1, 2, 4, 8, and 10 μM) and 10, 20, 30, and 40 weeks (0 and 0.5 μM). We found that arsenite increased the intracellular Ca levels and induced NFAT2 nuclear translocation after treatment for 24 h. The level of NFAT2 mRNA and expression of total protein and nuclear protein were increased after long-term treatment with 0.5 μM arsenite for 30 and 40 weeks compared to the cells treated for 24 h. In addition, NF-κB p50 and p65 nuclear protein expression increased significantly in cells treated with 2-8 μM arsenite for 24 h, which was consistent with NFAT2 nuclear expression. Furthermore, an ERK inhibitor (U0126) significantly reduced the expression of NFAT2 nuclear protein, and an ERK and JNK inhibitor decreased the levels of p65 and p50 nuclear protein. Cyclin D1 is known as a proto-oncogene and the level of this protein was increased in SV-HUC-1 cells treated with arsenite for 24 h and long-term. An NFAT inhibitor (CsA) and NF-κB inhibitor (PDTC) all markedly reduced Cyclin D1 protein expression. Treatment with U0126 also significantly decreased Cyclin D1 protein expression while JNK and p38 inhibitors did not attenuate the arsenite-associated increase in Cyclin D1 protein expression. The results suggest that regulation of Cyclin D1 protein expression by arsenite in SV-HUC-1 cells is dependent on ERK/NFAT2 and ERK/NF-κB, but is not dependent on JNK or p38.
为了了解砷处理膀胱细胞中细胞周期蛋白 D1（Cyclin D1）与活化 T 细胞核因子 2（NFAT2）和核因子（NF）-κB 之间的直接联系，以及 MAPK 和 NFAT 信号之间的关联，我们确定了 Ca/NFAT 途径是否在砷处理的正常尿路上皮细胞系中被激活，并确定了 NFAT 和 NF-κB 信号在调节 Cyclin D1 表达中的作用。SV-40 永生化人尿上皮细胞系 SV-HUC-1 用 NaAsO 处理 24 小时（0、1、2、4、8 和 10 μM）和 10、20、30 和 40 周（0 和 0.5 μM）。我们发现亚砷酸盐在处理 24 小时后增加了细胞内 Ca 水平并诱导 NFAT2 核转位。与处理 24 小时的细胞相比，长期用 0.5 μM 亚砷酸盐处理 30 和 40 周后，NFAT2 mRNA 水平和总蛋白及核蛋白表达增加。此外，用 2-8 μM 亚砷酸盐处理 24 小时后，NF-κB p50 和 p65 核蛋白表达显著增加，与 NFAT2 核表达一致。此外，ERK 抑制剂（U0126）显著降低 NFAT2 核蛋白表达，ERK 和 JNK 抑制剂降低 p65 和 p50 核蛋白水平。Cyclin D1 是一种原癌基因，这种蛋白质的水平在 SV-HUC-1 细胞中用砷处理 24 小时和长期处理后增加。NFAT 抑制剂（CsA）和 NF-κB 抑制剂（PDTC）均显著降低 Cyclin D1 蛋白表达。用 U0126 处理也显著降低了 Cyclin D1 蛋白表达，而 JNK 和 p38 抑制剂不能减轻砷相关的 Cyclin D1 蛋白表达增加。结果表明，SV-HUC-1 细胞中砷对 Cyclin D1 蛋白表达的调节依赖于 ERK/NFAT2 和 ERK/NF-κB，但不依赖于 JNK 或 p38。
