Expression of estrogen receptor β mRNA in endometrial carcinoma and its significance / 中华妇产科杂志

ABSTRACT

Objective　To investigate the expression of estrogen receptor β (ERβ ) mRNA and its significance in endometrial carcinoma. Methods　Thirty-six normal and 45 cancer tissue samples of endometrium were obtained, and the RNA was isolated from the tissues by the acid guanidium thiocyanate-phenol-chloroform extraction method. Reverse-transcription polymerase chain reaction (RT-PCR) was used to amplify the ERβ exon 5 wild type mRNA (ERβ WT) and splicing variant mRNA (ERβ E5SV). Electrophoresis of polymerase chain reaction product was performed and the ratio of ERβ E5SV/ERβ WT was calculated. The sequencing of ERβ E5SV and ERβ WT was carried out by express DNA sequencer. Results　ERβ E5SV and ERβ WT were both expressed in normal endometrium and endometrial cancer tissues. A region of 139 bp from base pair 812 to 950 (the hormone-binding domain) was found to be deleted in ERβ E5SV sequence as compared to ERβ WT. The quantity of ERβ E5SV was more than that of ERβ WT in every normal endometrium, and was less in every endometrial cancer, the ratio of ERβ E5SV/ERβ WT was 2.47±0.99 in normal endometrium, and 0.55±0.12 in endometrial cancer (P<0.000 1). The ratio of ERβ E5SV/ERβ WT decreased with the grade from 1 to 3 (P<0.01). Conclusion　Overexpression of ERβ WT relative to ERβ E5SV may correlate with the genesis of endometrial carcinoma.