Although E<sub>2</sub> and E<sub>3</sub> were equally efficacious and potent on the endogenous ERE-containing pS2 promoter in the MCF-7 BUS breast cancer cell line co-expressing ERα and ERβ, E<sub>1</sub> was less efficacious and potent than E<sub>2</sub>.
Expression of the pS2 gene which is transcriptionally controlled by oestrogens in the breast cancer cell line MCF-7 is oestrogen independent in stomach mucosa.
Genomic sequencing indicates a correlation between DNA hypomethylation in the 5' region of the pS2 gene and its expression in human breast cancer cell lines.
Nonetheless, these results collectively suggest that the novel PS-2 alleles described here, especially R71W, affect PS-2 function and may potentially confer a moderate risk of susceptibility to breast cancer.
The pS2 gene product was firstly identified as an oestrogen-induced molecule in a breast cancer cell line, while recent studies demonstrate a close association with mucus-secreting epithelia.
The pS2 gene encodes for a small cysteine-rich protein, and was originally found by differential screening of a cDNA library from the human breast carcinoma cell line, MCF-7.
The aim of this study was to determine whether expression of mRNA for the pS2 gene in breast cancer could contribute useful information on disease behaviour and survival at medium-term follow-up.
The expression of the pS2 gene, which is induced by estrogen in the breast cancer cell line MCF-7, has been investigated in breast cancers by using pS2 mRNA determination in tumor specimens and immunocytochemistry to identify pS2 protein in paraffin-embedded sections.
The human pS2 gene, whose expression is restricted to breast cancer cells, and whose transcription is induced by oestrogen in the human breast cancer cell line MCF-7, has been cloned from both placental and MCF-7 cell DNA.
These data clearly indicate that the breast-cancer-associated pS2 protein also plays an as yet undetermined role in the tumorigenesis of human colorectal carcinomas.