H. Ohlsson et al., Identification of two estrogen regulated genes associated with growth regulation of human breast cancer, MOL C ENDOC, 182(1), 2001, pp. 1-11
We have identified two estrogen regulated gene products in the E-2 growth i
nhibited human breast cancer xenograft, T61, one showing 100% homology to t
he human BAC clone RP11-112E16, the other 100% homology to the human CPR3/D
NJ3 gene, Verification by Northern blot analyses showed an up-regulation of
the BAC clone RP11-112E16 and the CPR3/DNJ3 mRNAs upon E-2 treatment, Trea
tment of T61 tumors with tamoxifen. leading to static tumor growth, also in
creased the expression of the BAC clone RP11-112E16 and the CPR3/DNJ3 mRNAs
. A similar association between growth inhibition and BAC clone RP11-112E16
and CPR3/DNJ3 mRNA induction was observed in MCF-7 cells treated with ICI
182.780. In MCF-7 cells, treatment with E-2 resulted in growth stimulation
concomitant with a decrease in the BAC clone RP11-112E16 and CPR3/DNJ3 mRNA
expression. Treatment with a combination of E-2 and ICI 182.780 abolished
the anti-estrogen induced increase in BAC clone RP11-112E16 and CPR3/DNJ3 m
RNA expression, indicating that regulation of the gene products is mediated
through the ER. The association between growth inhibition and BAC clone RP
11-112E16 or CPR3/DNJ3 mRNA expression was Supported by high expression of
both gene products in brain tissue, Further investigations are ongoing to c
larify the biological function of these two gene products. (C) 2001 Elsevie
r Science Ireland Ltd. All rights reserved.