Objectives. In order to identify the relationship between telomerase and the biological effect of radiation injury,and investigate the role of human telomerase catalytic subunit gene (hEST2) reverse transcriptase(RT) ...Objectives. In order to identify the relationship between telomerase and the biological effect of radiation injury,and investigate the role of human telomerase catalytic subunit gene (hEST2) reverse transcriptase(RT) segment in the expression of telomerase activity. Methods. Tumor HeLa cells, KB cells and A431 cells were employed to measure the change in telomerase activity after 60Co- ray irradiation at RNA level and protein level. Quantitative PCR and Northern blotting were used to determine the expression of hEST2 RT segment that encodes seven motifs of the human telomeres, a PCR- based telomeric repeat amplification protocol (TRAP)was used to assay telomerase activity after exposure to radiation. Results. Both of telomerase activity and the expression hEST2 RT segment were decreased with increasing dosage of radiation. In addition, testing the expression of motifs domain is similar to the measurement of telomerase activity. Conclusion. The detection of the hEST2 RT segment by Northern blotting and quantitative PCR are new methods for testing telomerase activity. Furthermore, radiation can cause a dose- dependent decrease in telomerase activity. The effect of radiation on telomerase is one possible reason for the death of cancer cells after irradiation.展开更多
To screen specific antitumor drugs targeting telomerase catalytic subunit (hEST2), 12 different hEST2 antisense oligonucleotides were designed based on hEST2 mRNA second structure and transfected into tumor cell lines...To screen specific antitumor drugs targeting telomerase catalytic subunit (hEST2), 12 different hEST2 antisense oligonucleotides were designed based on hEST2 mRNA second structure and transfected into tumor cell lines by the lipofectin-mediated method. Cell growth activity was evaluated by MTT assay. HEST212 was picked out and its specificity, antitumor tree and continuous effect were analyzed. The results showed that hEST212 had promising anti-tumor activity in vitro, hEST2 can be used as a pratical target and an antisense drug candidate for cancer.展开更多
文摘Objectives. In order to identify the relationship between telomerase and the biological effect of radiation injury,and investigate the role of human telomerase catalytic subunit gene (hEST2) reverse transcriptase(RT) segment in the expression of telomerase activity. Methods. Tumor HeLa cells, KB cells and A431 cells were employed to measure the change in telomerase activity after 60Co- ray irradiation at RNA level and protein level. Quantitative PCR and Northern blotting were used to determine the expression of hEST2 RT segment that encodes seven motifs of the human telomeres, a PCR- based telomeric repeat amplification protocol (TRAP)was used to assay telomerase activity after exposure to radiation. Results. Both of telomerase activity and the expression hEST2 RT segment were decreased with increasing dosage of radiation. In addition, testing the expression of motifs domain is similar to the measurement of telomerase activity. Conclusion. The detection of the hEST2 RT segment by Northern blotting and quantitative PCR are new methods for testing telomerase activity. Furthermore, radiation can cause a dose- dependent decrease in telomerase activity. The effect of radiation on telomerase is one possible reason for the death of cancer cells after irradiation.
基金This work was supported in part by the National Natural Science Foundation of China (Grant No. 39870879)the State "863" High-Tech Project (Grant Nos.102-08-04-01 and 2001AA215261) the Key Project from the Committee of Beijing Science Technology (Gra
文摘To screen specific antitumor drugs targeting telomerase catalytic subunit (hEST2), 12 different hEST2 antisense oligonucleotides were designed based on hEST2 mRNA second structure and transfected into tumor cell lines by the lipofectin-mediated method. Cell growth activity was evaluated by MTT assay. HEST212 was picked out and its specificity, antitumor tree and continuous effect were analyzed. The results showed that hEST212 had promising anti-tumor activity in vitro, hEST2 can be used as a pratical target and an antisense drug candidate for cancer.
