Immunosuppressant PG490 (triptolide) inhibits T-cell interleukin-2 expression at the level of purine-box/nuclear factor of activated T-cells and NF-kappaB transcriptional activation - Qiu,D.; Zhao,G.; Aoki,Y.; Shi,L.; Uyei,A.; Nazarian,S. (J Biol Chem, 1999)