title: Activity of telomerase and extracellular regulated protein kinases in parental and drug resistant cells of leukemia and ovarian cancer.
abstract: In order to study the role of telomerase and extracellular regulated protein kinase (ERK) in drug-resistance of leukemia and ovarian cancer cells, telomeric repeat amplification protocol (TRAP) assay and bioluminescence analysis were used for qualitative analysis or quantitative detection of telomerase activity respectively, and Western blot was used to detect the expression level of phosphorylatedly activated ERK(1) and ERK(2) protein in the parental and drug resistant cells of leukemia and ovarian cancer. In addition, chemotherapy sensitivity to HRT or DDP was evaluated by MTT assay. The difference of cell cycle distribution between parental cell and drug-resistant cell was analyzed by flow cytometry. The results showed that the drug resistant cells were of higher percentage in G(0)/G(1) phase compared with the parental cell lines. Telomerase activity and phosphorylatedly activated ERK(1) and ERK(2) protein expression level were higher in drug-resistant cells than in parental cell. It is suggested that the increasing number of the drug resistant cells in G(0)/G(1) phase may be considered as a sign of drug resistance. The up-regulation of telomerase activity and phosphorylatedly activated ERK(1) and ERK(2) protein expression level may play an important role in drug resistance of leukemia and ovarian cancer cell lines.
authors.affiliation: Department of Hematology, Tongji Hospital, Tongji Medical College, Huazhong Scientific and Technical University, Wuhan 430030, China.
authors.forename: Deng-Ju
authors.initials: DJ
authors.lastname: Li
authors.forename: Yao-Zhen
authors.initials: YZ
authors.lastname: Zhang
authors.forename: Dong-Hua
authors.initials: DH
authors.lastname: Zhang
mesh_terms: D002453:Cell Cycle; D019008:Drug Resistance, Neoplasm; D005260:Female; D018922:HL-60 Cells; D006801:Humans; D007938:Leukemia / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D019950:Mitogen-Activated Protein Kinase 1 / Q000032:analysis* / Q000502:physiology; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000032:analysis* / Q000502:physiology; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D010766:Phosphorylation; D019098:Telomerase / Q000378:metabolism*
chemical_list: D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D019098:Telomerase