Dihydrotanshinone I Inhibits the Lung Metastasis of Breast Cancer by Suppressing Neutrophil Extracellular Traps Formation
Huan Zhao, Yi Liang, Chengtao Sun, Yufei Zhai, Xuan Li, Mi Jiang, Ruiwen Yang, Xiaojuan Li, Qijin Shu, Guoyin Kai, Bing Han
Abstract
Breast cancer (BC) is a common female malignancy, worldwide. BC death is predominantly caused by lung metastasis. According to previous studies, Dihydrotanshinone I (DHT), a bioactive compound in Salvia miltiorrhiza Bunge (S. miltiorrhiza), has inhibitory effects on numerous cancers. Here, we investigated the anti-metastatic effect of DHT on BC, where DHT more strongly inhibited the growth of BC cells (MDA-MB-231, 4T1, MCF-7, and SKBR-3) than breast epithelial cells (MCF-10a). Additionally, DHT repressed the wound healing, invasion, and migration activities of 4T1 cells. In the 4T1 spontaneous metastasis model, DHT (20 mg/kg) blocked metastasis progression and distribution in the lung tissue by 74.9%. DHT reversed the formation of neutrophil extracellular traps (NETs) induced by phorbol 12-myristate 13-acetate, as well as ameliorated NETs-induced metastasis. Furthermore, it inhibited Ly6G+Mpo+ neutrophils infiltration and H3Cit expression in the lung tissues. RNA sequencing, western blot, and bioinformatical analysis indicated that TIMP1 could modulate DHT acting on lung metastasis inhibition. The study demonstrated a novel suppression mechanism of DHT on NETs formation to inhibit BC metastasis.