Life Sciences Commons^™

Role Of Stat3/5 And Bcl-2/Xl In 2-Methoxyestradiol-Induced Endoreduplication Of Nasopharyngeal Carcinoma Cells, Cm Ting, Ck Wong, Rn Wong, Kw Lo, Aw Lee, Gs Tsao, Ml Lung, N.K. Mak

Professor MAK, Nai Ki

2-methoxyestradiol (2ME2), an endogenous metabolite of 17-b-estradiol, has been shown to induce apoptosis and cell cycle arrest in various tumor models. We have previously shown that 2ME2 induced endoreduplication in a welldifferentiated nasopharyngeal carcinoma (NPC) HK-1 and a poorly differentiated C666-1 cell line. In the present study, we studied the survival factors involved in 2ME2-induced endoreduplicating NPC cells. In the HK-1 cells, knockdown of BcL-xL expression by siRNA resulted in the reduction of endoreduplication and an increase in the percentage of apoptosis. Further mechanistic study revealed that 2ME2 enhanced the expression of the phosphorylated form of STAT5 (p-STAT5-Y694), but not …