Telomerase-mediated apoptosis of chicken lymphoblastoid tumor cell line by lanthanum chloride.

To investigate the biological effects of lanthanum on chicken lymphoid tumors, cultures of the MDCC-MSB1 chicken lymphoblastoid cell line were treated with 2.5 mM lanthanum chloride for 2 days at 12-h intervals. The apoptotic cells were detected using the TdT-mediated dUTP nick end labeling assay and flow cytometer analysis. The telomerase activity and the chTERT mRNA expression levels of the MDCC-MSB1 cells were examined. The results showed that MDCC-MSB1 cell apoptosis occurred after incubation for 12 to 48 h induced by 2.5 mM LaCl(3). Consistent with the apoptosis results, telomerase activities in LaCl(3)-treated cells significantly decreased (P < 0.05) compared with 0 h group. Furthermore, the transcription of chTERT gene in MDCC-MSB1 cell was significantly inhibited in LaCl(3) treatment group (P < 0.05). These results suggest that the decrease of the chTERT transcription and telomerase activity play an important role in the La-induced apoptosis in chicken lymphoid tumor.