Effects of triiodothyronine on estrogen receptor-? and thyroid hormone receptor-? in breast cancer cells / 中国癌症杂志

ABSTRACT

Background and purpose:The effects of triiodothyronine(T3)on breast cancer remain unclear.The aim of this study was to investigate the expression and correlation of estrogen receptor-?(ER-?)and thyroid hormone receptor-?(TR-?)in breast cancer cell lines,and to determine the changes of relevant receptors expression and its possible mechanism due to T3 treatment.Methods:Real-Time PCR was used to analyze the expressions of ER-? and TR-? at mRNA level in seven breast cancer cell lines.The expression level of retinoid X receptor-?(RXR-?)and these two receptors after T3 treatment were determined as well.The gene profile was further determined in SK-BR-3 cells treated with T3.Results:The expressions of ER-? and TR-? were quite low in SK-BR-3,MDA-MB-231 and MDA-MB-435 cells,but high in MCF7,BT20,BT474 and T47D cells.ER-?,TR-? and RXR-? were upregulated due to T3 treatment in ER-?(-)cells,but not in ER-?(+)cells.In SK-BR-3 cells,T3 treatment led to up-regulation of E2F1,TGF-?1R,TGF-?2R and hTERT,but down-regulation of TGF-?1 and p21.Conclusions:The expressions of ER-? and TR-? are correlated in breast cancer cells;the effect of T3 treatment on hormone receptors is associated with endogenous ER-? level.