Activation of LMP1 to Telomerase in Human Nasopharyngeal Cell Line, CNE1 and Related Regulation Mechanisms

Objective 　To explore the influence to telomerase activity and related regulation mechanisms of LMP1 in a NPC cell line, CNE1. Methods 　The expressions of LMP1, NF2κB, c2myc and hTERT, the lev2 el of hTERT mRNA and the telomerase activity were respectively detected by SP, RT2PCR and PCR2 EL ISA methods in NPC cell line CNE1, CNE1 GL (CNE1 t ransfected with an eukaryotic plasmid, PAT2 GFP2LMP1) and CNE22Z. Results 　(1) The expressions of LMP1, NF2κB, c2myc and hTERT in CNE1 GL is higher than those in CNE1 ( P < 0. 01) . Among three types of cells, the expressions of LMP1, NF2κB and c2myc and hTERT in CNE22Z was highest ( P < 0. 01 or P < 0. 05) . Pearson correlation analysis showed that the expressions between LMP1 and NF2κB, NF2κB and c2myc, LMP1 and c2myc in CNE1 GL were significantly correlated ( P < 0. 01 or P < 0. 05) . ( 2) The hTERT mRNA level in CNE1 GL was higher than that in CNE1, the difference was statistial significant ( P < 0. 01) ; the hTERT mRNA level in CNE22Z was highest in three types of cells ( P < 0. 01) . (3) The telomerase activity in CNE1 GL was high2 er than that in CNE1, the difference was statistical significant ( P < 0. 05 ) ; the telomerase activity in CNE1 GL was a little lower than that in CNE22Z( P > 0. 05) ; the telomerase activity in CNE22Z was high2 er than that in CNE1 ( P < 0. 01) . Conclusion 　LMP1 activates telomerase by activating hTERT t ranscrip2 tion. This process is possibly related to NF2κB activation by LMP1, upregulating the expression of c2myc by NF2κB and improving t ranscription level of hTERT by c2myc in CNE1 GL. Telomerase activation by LMP1 may be an important occurrence in the stage of tumorigeness of NPC.