ABSTRACT
Objective To investigate the different effect of exogenous leptin on estrogen receptor α,β mRNA in human breast tumor tissue in nude mice xenograft models. Methods We made nude mice xenograft models of MCF-7 human breast cancer cells cultured in vitro, then divided them into experimental group of]eptin( n = 30)and control group of normal saline( n = 30)randomly. The models of experimental group were injected subcutaneously the recombinant human leptin for 15 consecutive days, the models of control group were injected subcutaneously the same dose of normal saline. A real- time quantitative RT- PCR assay was developed to quantify the expression of estrogen receptor α, β mRNA in tumor tissue, using the relative quantitative analysis. Results The leptin-intervened nude mice xenograft models were safely established. The relative quantitation of estrogen receptor α mRNA was significantly higher in the leptin group than in the normal saline group ( P ＜ 0.01 ), the relative quantitation of estrogen receptor β mRNA was significantly lower in the leptin group than in the normal saline group ( P ＜ 0. 01 ). Conclusion The nude mice xenograft models can be safely intervened with human leptin by subcutaneous injection around tumor.Estrogen receptor is one of the targets of leptin in the progress of breast cancer. Exogenous human leptin can up- regulate the expression of estrogen receptor α and down- regulate the expression of the estrogen receptor βin nude mice xenograft models of human breast tumor.