Significant anti-myeloma potential of green tea infusion and its component dihydromyricetin.

Multiple myeloma (MM) is a fatal hematological malignancy characterized by overgrowth of monoclonal plasma cells. Although green tea exhibits well-documented antitumor properties, its specific effects against MM remain poorly characterized. This study aimed to investigate the anti-myeloma activity of infusions from four representative green teas and identify their effective components. We found that apoptosis of MM cells was induced by green tea infusions in a concentration-dependent manner, with Biluochun tea infusion showing the most potent efficacy. An animal study showed that Biluochun tea infusion significantly reduced MM tumor size, downregulated the proliferation marker Ki-67, and increased TUNEL-positive apoptotic cells in MM tumor tissues. Furthermore, mass spectrometry analysis identified dihydromyricetin (DMY) as a pivotal distinguishing component of Biluochun among the four tea infusions. As expected, DMY induced apoptosis in MM cells in a concentration-dependent manner, accompanied by decreased mitochondrial membrane potential and elevated expression of cleaved caspase-3 and caspase-8. These findings indicate that DMY elicits anti-myeloma effects through activation of both the intrinsic mitochondrial and extrinsic apoptotic pathways. Collectively, this study provides preliminary preclinical evidence supporting the anti-myeloma activity of DMY in cell and xenograft mouse models, which lays a foundation for subsequent translational research exploring green tea-derived compounds against MM; further multilayered validation is required to confirm its clinical value.