Effects of Naturally Occurring Polymethyoxyflavonoids on Cell Growth, P-Glycoprotein Function, Cell Cycle, and Apoptosis of Daunorubicin-Resistant T Lymphoblastoid Leukemia Cells

ABSTRACT

Effects of polymethoxyflavonoids tangeretin and nobiletin and the related polyphenolic compounds baicalein, wogonin, quercetin, and epigallocatechin gallate on the cell growth, P-glycoprotein function, apoptosis, and cell cycle of human T lymphoblastoid leukemia MOLT-4 and its daunorubicin-resistant cells were investigated. The IC50 values of these compounds on the cell growth were 7.1–32.2 μmol/L, and the inhibitory effects were observed to be almost equal to the parent MOLT-4 and the daunorubicin-resistant cells. Tangeretin and nobiletin showed the strongest effects with the IC50 values of 7.1–14.0 μmol/L. These polymethoxyflavonoids inhibited the P-glycoprotein function and significantly influenced the cell cycle (p<.05), whereas they did not induce apoptosis.

Keywords: :

• Naturally occurring polymethoxyflavonoids
• MOLT-4 cell line
• Daunorubicin resistance
• P-glycoprotein function
• Cell cycle
• Apoptosis