Platyphylloside Isolated from Betula platyphylla is Antiproliferative and Induces Apoptosis in Colon Cancer and Leukemic Cells

Abstract

Betula platyphylla bark has been evaluated for the treatment of dermatitis, inflammatory conditions, and cancer. Diarylheptanoids are the major constituents of the B. platyphylla bark and possess various pharmacological effects. Our previous study confirmed the selective antiproliferative effect of platyphylloside (BPP) isolated from B. platyphylla on colon cancer and leukemic cells using 60 different cancer cell lines from thr National Cancer Institution (NCI). In line with previous reports, this study focuses on the apoptotic pathway of BPP, a phenolic glycoside composed of two aromatic rings joined by a seven-carbon chain. Cytotoxicity assays in solid tumor and blood cancer cell models demonstrated that BPP possesses potent antiproliferative activity. The level of apoptosis increased with BPP treatment, causing cell cycle arrest at the G1 phase along with the downregulation of IκBα phosphorylation and BCL-2, as well as upregulation of cleaved caspase 3 and BAX proteins. In addition, BPP displayed potent mitochondrial depolarization effects in Jurkat cells. The combined findings revealed that the cytotoxic effects of BPP were mediated by intracellular signaling, possibly through a mechanism involving the upregulation of mitochondrial reactive oxygen species (ROS). Thus, BPP could be a potential multitarget therapeutic agent in leukemia and colon cancer.