| Objection: Telomerase, a unique ribonucleoprotein with reverse transcriptase activity, and its RNA component acts as the template and the telomeric DNA sequences synthesized by telomerase.The abnormal construction and behavior of telomerase has been shown to be pivotal in the control of cellular life span and the multiplication of some cancer. Lots of datas proved that telomerase activity has been found in 85% of all human cancers, but not in most somatic cells and benign tumor tissues. Many schola rs thought that the proliferation of some cancers could be restrained by the inhibitors of telomerase, telomerase has been explored as a promising biomarker and target in cancer diagnosis and therapy. From the 1990s, many strategyies of gene therapy aiming at inhibiting telomerase activity has been put forward. The inhibitors expected to be empoldered that can inhibit the telomerase activity and the genic expression. So that cancer can be cured.Human hepatocellular carcinoma (HCC) and nasopharyngeal carcinoma (NPC) are the critical diseases threatening human health. They have high incidence rate in Guangxi.However there is no effective treatment at present and the chemotherapy can often bring the drug resistance and side effect. Therefore, investigating the new biotherapeutic method with light side effect is the objective of medical workers.The development of telomerase researching may provid new method for the therapy of cancer. To discuss the mechanism of telomerase inhibitors on cancer, human hepatocelluar cancer cell line SMMC-7721 and nasopharyngeal carcinoma (NPC) cell line LXC treated by 8 telomerase inhibitors were studied.The telomerase activity inhibited by inhibitors was evaluated. Methods: First, combining real-time quantitative PCR with TRAP assay and SYBR-Green I, a novel method (FQ-TRAP assay ) quantitative detecting telomerase activity was established in the present study . Second, cultured cells were harvested at log phase.Cells were treated by telomerase inhibitors and were divided into nine groups ASODN, HASODN, NODN, HNODN, EGCG, AZT, ADM, ATRA and control without treating. The various concentration of drugs was used in each group. The proliferation of carcinoma cells and the cytotoxicity of drugs were observed by MTT assay. The optimized concentration and time of telomerase inhibitors decided by MTT assay. Third, the telomerase activity of carcinoma cells treated by telomerase inhibitors was detected by FQ-TRAP assay. Fourth,the apoptosis of carcinoma cells treated by telomerase inhibitors was detected by TUNEL methods and analyzed by flow cytometry(FCM)assay.At last, the change of molecule structural in carcinoma cells treated by telomerase inhibitors were monitored by raman spectra assay. Results: The telomerase activity of 100 cells in cell extract was detected by a novel real-time quantitative telomerase detection method (FQ-TRAP).The FQ-TRAP is a sensitive, special and repetitive method of telomerase activity assay. Carcinoma cells under various time treated with telomerase inhibitors, with the increasing of concentration and the prolong of time of inhibitors, the surviving rate of cells reduced step by step. Except that NODN and control, the growth of carcinoma cells inhibited by all of the rest drugs. When the SMMC-7721 cells were treated with ASODN,HASODN,HNODN,EGCG,AZT,ADM,ATRA for 48h, the inhibiting rate of SMMC-7721 cells was 54.20%,58.40%,47.40%,60.00%,50.00%,50.00% and 54.40% respectively, the appropriate concentration of drugs was 6μmol/L,5μmol/L,5μmol/L,125mg/L,20mmol/L,1.25mg/L and 10μmol/L respectively. When the LXC cells were treated with ASODN,HASODN,HNODN,EGCG,AZT,ADM,ATRA for 48h, the inhibiting rate of LXC cells was 54.52%,56.52%,40.29%,54.87%,51.31%,56.31% and 54.61% respectively, the appropriate concentration of drugs was 6μmol/L,5μmol/L,5μmol/L,250mg/L,10mmol/L,2.5mg/L and 10μmol/L respectively. Telomerase activity of carcinoma cells treated with vavious telomerase inhibitors were detected by FQ-TRAP assay.Except ASODN, NODN groups on LXC cells, the do...
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