The Telomerase and Alternative Lengthening of Telomeres Mechanisms Regulate Laryngeal Cancer Cell Apoptosis via the PI3K/Akt Pathway.

PURPOSE: To investigate the possible telomerase and alternative lengthening of telomeres (ALT) mechanisms influencing the apoptosis of laryngeal squamous cells. MATERIALS AND METHODS: The effects of the telomerase mechanism were observed by knockdown of human telomerase reverse transcriptase (hTERT). The ALT mechanism was induced by silencing related genes including TRF2, RAD51, and NBS1. Effects of telomerase and ALT mechanisms on tumor development were confirmed by xenograft tumors model. Tumor cell apoptosis was investigated by flow cytometry and Hoechst staining. Caspase-3 activity assay and Western blot were performed to investigate the possible mechanisms. RESULTS: After silencing ALT- and telomerase mechanism-related genes, Bax and Bcl-2 were increased, and nuclear factor (NF)-κB translocation and PI3K/Akt phosphorylation were inhibited. CONCLUSIONS: The inhibition of telomere-related genes inhibited the growth of laryngeal squamous cell carcinoma by promoting cell apoptosis via the PI3K/Akt pathway.