Plasmids, siRNAs, shRNAs, and reagents
PES1 conditional KO mice
PES1 KO MCF7 cells
Cell culture and transfection
Mass spectrometry
Co-immunoprecipitation
GST/His pull-down assay
Fast protein liquid chromatography
Immunofluorescence
Cell cycle synchronization
RNA binding protein IP assay
RNA pull-down assay
Quantitative RT-PCR
TRAP assay
IP-TRAP
Direct telomerase activity assay
TRF assay
SA-β-gal staining
BrdU incorporation assay
Population doubling levels
Cell proliferation assay
Apoptosis analysis
Immunohistochemistry
Trial experiments or similar experiments done previously were used to assess sample size with adequate statistical power. Statistical significance in SA-β-gal staining, PDLs, and BrdU incorporation assay was assessed by two-tailed Student’s t test. The correlation of PES1 expression with telomerase activity and telomere length was determined using the Mann-Whitney test. The correlation between PES1 expression and SA-β-gal staining in clinical samples was determined using Fisher’s exact test. All statistical tests were two-sided. Statistical calculations were performed using SPSS 18.0. In all assays, P < 0.05 was considered statistically significant.