Coexpression of wild-type and variant oestrogen receptor mRNAs in a panel of human breast cancer cell lines.
Br J Cancer
; 71(5): 974-80, 1995 May.
Article
en En
| MEDLINE
| ID: mdl-7734323
Wild-type as well as variant oestrogen receptor (ER) mRNAs with exon 5 and 7 deleted were identified in a panel of human breast tumour cell lines by reverse transcriptase-polymerase chain reaction followed by dideoxynucleotide sequence analysis, and then quantitated by ribonuclease protection analysis. All cell lines categorised as ER+ by ligand-binding analysis expressed both wild-type and variant ER transcripts. Most cell lines classified as ER- did not express any ER transcript. However, three ER- cell lines (BT-20, MDA-MB-330 and T47Dco) expressed both wild-type and variant transcripts. A differential pattern of expression of wild type to variant was seen in both ER+ and ER- cell lines, however this pattern was not paralleled by differences in ligand-binding activity. Breast tumour cell lines previously classified as ER- expressed significantly lower levels of ER transcripts than did their ER+ counterparts. In view of these findings, as well as earlier reports that the exon 5 deletion ER variant encodes a dominant-positive receptor, it seems clear that some cell lines are misclassified as ER-, and express both wild-type and variant ER mRNAs, and that the overexpression of this variant may account, in part, for their oestrogen-independent phenotype.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias de la Mama
/
ARN Mensajero
/
Receptores de Estrógenos
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Neoplasias Hormono-Dependientes
Tipo de estudio:
Prognostic_studies
Límite:
Humans
Idioma:
En
Revista:
Br J Cancer
Año:
1995
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Reino Unido