Determining the estrogen‐sensitivity of the ER‐alpha mRNA half‐life in human breast cell lines

Abstract

In two normal estrogen-responsive tissues mammalian endometrium and fish liver, the ER-alpha mRNA half-life increases in response to estrogen treatment. However, Mary Beth Martin and colleagues (1998) found estrogen treatment decreased the ER-alpha mRNA stability in the MCF7 breast cancer cell line. The goal of this research was to test the estrogen-sensitivity of the half-life for the ER-alpha mRNA in other breast cancer cell lines and in a normal breast epithelial cell line. Thus in addition to MCF7 cells, we tested two estrogen-responsive breast cancer cell lines, BT474 and T47D, and the normal estrogen-responsive breast epithelial cell line, HCC1500. 17beta-estradiol treated (6hrs) cells were harvested after exposure to actinomycin D for various times (0.5 to 6 hours) and the total RNA was isolated using a Qiagen RNeasy kit. The isolated RNA was used in quantitative real time RT-PCR in order to determine the half-life of the ER-alpha mRNA. Preliminary data indicates that ER-alpha mRNA half-life decreases similarly in the tested breast cancer cell lines but increases in the normal breast epithelial cell line.