Baohuoside I Suppresses Invasion of Cervical and Breast Cancer Cells through the Downregulation of CXCR4 Chemokine Receptor Expression

Buyun Kim and Byoungduck Park

Abstract

More than 90 percent of cancer-mediated deaths are due to metastasis, but the mechanisms that control metastasis remain poorly understood. Thus, the therapy targeting this process has been challenged constantly, but no therapy has yet been approved. CXC chemokine receptor 4 (CXCR4), a Gi protein-coupled receptor for the CXC chemokine ligand (CXCL) 12/stromal cell derived factor (SDF) 1α, is known to be expressed in various tumors. Recently, the CXCL12/CXCR4 axis has emerged as a key mediator of tumor metastasis; therefore, the possibility that identification of CXCR4 inhibitors can be a promising strategy for abrogating metastasis has been considered. In this report, we investigate baohuoside I, a component of Epimedium koreanum, as a regulator of CXCR4 expression as well as function in cervical cancer and breast cancer cells. We observed that baohuoside I downregulated CXCR4 expression in a dose- and time-dependent manner in HeLa cells. Treatment with a pharmacological proteasome and lysosomal inhibitors did not have a substantial effect on baohuoside I’s ability to suppress CXCR4 expression. When we investigated the

 Materials Baohuoside I (99% pure) was purchased from Biopurify Phytochemicals Ltd. (Chengdu, China).