Microarray-based mRNA expression profiling of leukemia cells treated with the flavonoid, casticin.

Natural polyphenols play an important role in tumor inhibition. We used a doxorubicin-sensitive acute T-lymphoblastic leukemia cell line (CCRF-CEM) and its multidrug-resistant subline (CEM/ADR5000) to evaluate the activity of 15 plant polyphenols isolated in our laboratory (hypericin and pseudohypericin, verbascoside, ellagic acid, casticin, kaempferol-3-O-(2'',6''-di-E-p-coumaroyl)-glucopyranoside, kaempferol-3-O-(3,4-diacetyl-2,6-di-E-p-coumaroyl) -glucopyranoside, tiliroside, salvianolic acid B, oleuropein, rosmarinic acid, bergenin) or of others from commercial sources (curcumin, epigallocatechin-3-gallate, silymarin). Casticin was the most potent compound (IC50 values of 0.28 ± 0.02 μM in CCRF-CEM and 0.44 ± 0.17 μM in CEM/ADR5000 cells. The IC50 values of the other compounds tested ranged from 1.52 μM to 164.1 μM. A microarray-based mRNA expression profiling of CCRF-CEM cells treated with casticin was performed in order to identify genes with altered expression following casticin treatment. Networks related to NF-κB, p38MAPK, histones H3 and H4, and follicle stimulating hormone were identified.