Magnesium Lithospermate B Inhibits Colorectal Cancer Cell Progression Through JAK2-STAT3 Signaling

Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second leading cause of cancer death worldwide. The discovery of new effective therapeutic drugs is always a priority. Magnesium lithospermate B (MLB), a native polyphenol acid, is the major component of the aqueous extracts from Danshen, a traditional Chinese medicine derived from the dry root and rhizome of Salvia miltiorrhiza. MLB has been reported to have antioxidant, anti-inflammatory, and ion channel-regulating activities in several diseases, including cardiovascular, renal, and neuronal diseases. However, the effect of MLB on cancer progression has not been reported. In this study, a series of cellular and molecular experiments were conducted on two CRC cell lines (HCT116 and SW480) to investigate the effects of. The results demonstrated that MLB exerted inhibitory effects on cell proliferation, migration, and invasion. The administration of 50 mg/kg MLB inhibited tumor growth in HCT116 cells in xenografted models. Importantly, we found that MLB treatment inhibited the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway, and activation of JAK2-STAT3 signaling with interleukin 6 or overexpression STAT3 significantly suppressed the inhibitory effect of MLB. These findings provide evidence that MLB could inhibit CRC cell progression in vitro and might serve as a potential therapeutic drug for the treatment of CRC.