Figure 1.

Natural product Glaucarubin specifically inhibits the growth of MCPyV-positive MCC MKL-1 cells. (A) Chemical structure of glaucarubin, a compound from the NCI Natural Product Set IV plate of identified to be toxic in MKL-1 MCC cells. (B) Assay of cell viability in the MCPyV-positive MCC cell line MKL-1; variant MCPyV-negative MCC cell lines UISO, MCC13, and MCC26; and primary HDFs subjected to the indicated concentrations for three days at 37 °C in 5% CO₂. Cell viabilities were measured by cellTiter-GLO 3D cell viability assay (Promega). The growth curves were generated using GraphPad Prism software. (C) IC50 (μM) concentrations of glaucarubin for MCCs and HDF cells.