Xihuang pill suppresses triple-negative breast cancer via regulating AXL/TGF-β1/RhoA/ROCK and ERK pathway

Xihuang pill (XHP), a traditional prescription for treating "Ru yan (breast cancer)" for 270 years, has the efficacies of clearing heat and improving blood circulation. Previous research has demonstrated that XHP yields significant therapeutic effects in the management of triple-negative breast cancer (TNBC).

To explore and validate the usage of a traditional Chinese medicine formula XHP in combating TNBC by epithelial-mesenchymal transition (EMT) and apoptosis mechanisms.

The cytotoxic effects of XHP were evaluated using the CCK-8 assay after incubating with 4T1 and MDA-MB-231 TNBC cell lines. WB assay was conducted to detect the expression of proteins associated with EMT and apoptosis signaling pathways, elucidating the mechanism by which XHP inhibits TNBC. DAPI staining, and mitochondrial membrane potential (MMP) assays (JC-1) were utilized to further confirm the effect of apoptosis in TNBC. Moreover, morphological examination, wound healing assays, and transwell experiments were used to investigate the EMT properties of XHP. Besides, this study constructed 4T1-xenograft model to assess the anti-tumor efficacy of XHP, while the underlying mechanism was revealed by H&E staining.

XHP suppressed tumor growth and metastasis in Balb/c transplanted tumor model by inducing EMT and apoptosis. XHP modulated the expression of the AXL/TGF-β1/RhoA/ROCK pathway, reducing tumor cell EMT, and influencing the ERK signaling pathway. Moreover, XHP inhibited the expression level of Bcl2, Bax and caspase 9 to promote apoptosis in tumor cells. These phenomena eventually manifested as inhibiting the proliferation and migration of TNBC cells.

XHP inhibits TNBC and regulates EMT and apoptosis phenotypes by regulating the AXL/TGF-β1/RhoA/ROCK and ERK pathways. Therefore, it could be further utilized in the discovery of anti-cancer drugs.