5-[(4-Ethylphenyl)methylene]-2-thioxo-4-thiazolidinone

c-Myc is a proto-oncogene that plays an important role in cell proliferation, differentiation, and apoptosis. 5-[(4-Ethylphenyl)methylene]-2-thioxo-4-thiazolidinone [10058-F4] is a cell-permeable thiazolidinone compound that specifically inhibits the c-Myc-Max interaction/dimerization at 64 µM, preventing c-Myc-dependent gene expression and cell proliferation. 10058-F4 inhibits tumor cell growth and proliferation in a c-Myc-dependent manner both in vitro and in vivo. 10058-F4 induces cell-cycle arrest (G0/G1 phase) and apoptosis. 10058-F4 has been found to also upregulate cyclin-dependent kinase (CDK) inhibitors, p21 and p27. In addition to c-Myc, 10058-F4 inhibits the nuclear Myc protein, N-Myc, at 50 µM, inducing arrest, apoptosis, and differentiation in neuroblastoma cells overexpressing the gene for N-Myc. This compound can be used to delineate novel actions of Myc proteins, especially those related to lipid and glucose metabolism. 10058-F4 downregulates human telomerase reverse transcriptase and enhances chemosensitivity in several human cancer cell lines.