Changes in telomerase activity decreases in MCF-7 cells during apoptosis induced by sodium butyrate.
- Author:
Ling XI
1
;
Ming-Fu WU
;
Jian-Hong WU
;
Fu-Jun LI
;
Yun-Ping LU
;
Jian-Feng ZHOU
;
Ding MA
Author Information
- Publication Type:Journal Article
- MeSH: Apoptosis; drug effects; Breast Neoplasms; enzymology; pathology; Butyrates; administration & dosage; pharmacology; Cell Line, Tumor; DNA-Binding Proteins; biosynthesis; genetics; Dose-Response Relationship, Drug; Humans; RNA, Messenger; biosynthesis; genetics; Telomerase; biosynthesis; genetics; metabolism; Time Factors
- From: Chinese Journal of Oncology 2005;27(1):9-12
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate telomerase activity of MCF-7 mammary cancer cells during apoptosis induced by sodium butyrate (SB) in vitro and its mechanism.
METHODSThe proliferative activity of MCF-7 cells was assessed by morphology and MTT assay. Cell apoptosis was confirmed by DNA fragmentation and phosphatidylserine (PS) externalization. Telomerase activity was examined by TRAP-ELISA. The expression status of telomerase subunits was analyzed by RT-PCR.
RESULTSA time- and dose-dependent inhibition was detected in MCF-7 cells treated with SB. At 72 hr after SB (2.5 mmol/L) treatment, MCF-7 cells were apoptotic with a rate of 84.3% by flow cytometric assay (AnnexinV/PI double staining). Apoptosis was also confirmed by DNA fragmentation. Telomerase activity and expression level of hTERT, the key subunit of telomerase, decreased at 24-hour time point after SB treatment. No significant changes were observed in the expression of hTR and hTP, the other two subunits of telomerase.
CONCLUSIONTelomerase activity decreases in MCF-7 cells during apoptosis induced by sodium butyrate. The underlying mechanism might be related to the down regulation of hTERT transcription.
