Cryptotanshinone (Tanshinone c) is a natural product derived from Salvia miltiorrhiza and can inhibit STAT3 (IC50=4.6 μM). Cryptotanshinone has antitumor activity.

STAT3:4.6 μM

方法：人肺癌细胞 H446 用 Cryptotanshinone (5-20 µM) 处理 24-72 h，使用 CCK-8 assay 检测细胞活力。
结果：Cryptotanshinone 以浓度和时间依赖的方式显著抑制 H446 细胞的生长。48 h 后，Cryptotanshinone 在 10 µM 下抑制 H446 细胞生长 40%。[1]
方法：人肺癌细胞 A549 用 Cryptotanshinone (20 µM) 处理 48 h，使用 Western Blot 检测靶点蛋白表达水平。
结果：Cryptotanshinone 处理后，G2/M 期相关蛋白细胞周期蛋白 B1、CDK1 和 CDC25C 的表达下调，而 p21 (CIP1/WAF1) 上调。关于凋亡相关蛋白，Cryptotanshinone 处理后，Bcl-2 的表达下调，而 p53 和 Bax 的表达上调。[2]

方法：为研究对梗阻性肾脏炎症和氧化应激的影响，将 Cryptotanshinone (50-100 mg/kg) 灌胃给药给构建单侧输尿管梗阻 (UUO) 模型的 C57/BL6 小鼠，每天一次，持续十四天。
结果：Cryptotanshinone 可以通过调节 NF-κB 和 Nrf-2/HO-1 信号通路来改善炎症和氧化应激，从而保护肾间质纤维化。[3]

STAT3-dependent dual-luciferase assay: HCT-116 cells are transiently transfected with reporter plasmid having the STAT3-binding element for regulating luciferase assay. Cells are treated with Cryptotanshinone for 24 hours at a concentration range of 0.2 to 50 μM. After treatment, cells are harvested in 20 μL of passive lysis buffer and luciferase activity is evaluated by the Dual Luciferase Reporter Assay kit on Wallac Victor2. The concentration of Cryptotanshinone that inhibits the luciferase activity by 50% represents IC50 value.

Cells are exposed to Cryptotanshinone for 24 or 48 hours. For the determination of cell proliferation, the cell proliferation reagent WST-1 is added and WST-1 formazan is quantitatively measured at 450 nm using an ELISA reader.(Only for Reference)