Division of Endocrinology and Metabolism, Department of Internal Medicine, College of Medicine, Hallym University, Chuncheon 200-704, Republic of Korea.
J Endocrinol Invest. 2013 Dec;36(11):1099-104. doi: 10.3275/9099. Epub 2013 Sep 27.
Aim of the present study was to evaluate the effect of apigenin in combination with BRAFV600E inhibitor PLX4032 on cell survival, and to investigate the influence of Akt inhibition on the combined effect of apigenin and PLX4032 in ATC cells harboring BRAFV600E. In 8505C and FRO cells harboring BRAFV600E, after treatment of apigenin and PLX4032, the cell viability decreased, and the percentage of dead cells increased in a time- and concentration-dependent manner, respectively. In apigenin- and PLX4032- treated cells, compared with apigenin alone-treated cells, the cell viability was lessened, and the percentage of dead cells was multiplied. In the addition of PLX4032 to apigenin, compared with the treatment of apigenin alone, the protein levels of cleaved PARP-1 and cleaved caspase-3 were elevated, and phospho-ERK protein levels were reduced, and the protein levels of total ERK, c-Myc, BRAF, phospho-Akt, phospho-p70S6K and phospho-4EBP1 were not varied. Compared with the treatment of PLX4032 alone, phosphop70S6K protein levels were reduced, and the other protein levels were not altered. Phospho-ERK protein levels were reduced only in 8505C cells. Under the co-treatment of apigenin and PLX4032, administration of the PI3K inhibitor wortmannin further decreased the cell viability, and increased the percentage of dead cells. In conclusion, our results suggest that PLX4032 augments apigenin-induced cytotoxicity in ATC cells harboring BRAFV600E. Moreover, Akt suppression potentiates the combined effect of apigenin and PLX4032 in ATC cells harboring BRAFV600E.
本研究旨在评估芹菜素联合 BRAFV600E 抑制剂 PLX4032 对细胞存活的影响，并研究 Akt 抑制对 BRAFV600E 阳性 ATC 细胞中芹菜素和 PLX4032 联合作用的影响。在携带 BRAFV600E 的 8505C 和 FRO 细胞中，芹菜素和 PLX4032 处理后，细胞活力呈时间和浓度依赖性下降，死亡细胞比例增加。在芹菜素和 PLX4032 处理的细胞中，与单独用芹菜素处理的细胞相比，细胞活力降低，死亡细胞比例增加。在添加 PLX4032 到芹菜素中，与单独用芹菜素处理相比，裂解的 PARP-1 和裂解的 caspase-3 蛋白水平升高，磷酸化 ERK 蛋白水平降低，总 ERK、c-Myc、BRAF、磷酸化 Akt、磷酸化 p70S6K 和磷酸化 4EBP1 蛋白水平没有变化。与单独用 PLX4032 处理相比，磷酸化 p70S6K 蛋白水平降低，其他蛋白水平没有改变。只有在 8505C 细胞中，磷酸化 ERK 蛋白水平降低。在芹菜素和 PLX4032 的共同处理下，给予 PI3K 抑制剂wortmannin 进一步降低了细胞活力，增加了死亡细胞的比例。综上所述，我们的结果表明，PLX4032 增强了 BRAFV600E 阳性 ATC 细胞中芹菜素诱导的细胞毒性。此外，Akt 抑制增强了 BRAFV600E 阳性 ATC 细胞中芹菜素和 PLX4032 的联合作用。
