title: Ultraviolet irradiation- and dimethyl sulfoxide-induced telomerase activity in ovarian epithelial cell lines.
abstract: Information about telomerase regulation is incomplete, especially since various studies suggest complexity in telomerase regulation. Given the important association between telomerase and cancer, it is imperative to design and develop a model system in which telomerase activity can be regulated and studied. We employed ultraviolet (UV) radiation or dimethyl sulfoxide (DMSO) to transiently induce telomerase activity in a telomerase-positive cell line and, most importantly, in a telomerase-negative cell line. UV- or DMSO-induced telomerase activity was associated with increased hTRT, but not hTR, mRNA transcription in the telomerase-negative cells. However, no changes in hTRT or hTR mRNA transcription were noted with UV- or DMSO-induced telomerase activity in the telomerase-positive cells. Inhibition of protein synthesis or the phosphotidyl inositol 3-kinase (PI3K) pathway suppressed telomerase induction and/or activity in all cell lines examined, suggesting telomerase activity was dependent on protein synthesis and PI3K-mediated phosphorylation. Furthermore, enhanced telomerase activity was limited to UV and DMSO, since a variety of chemotherapeutic agents failed to induce telomerase activity. Therefore, our data provide a useful culture model system to study telomerase regulation in telomerase-negative and -positive cell lines and from which to obtain information about telomerase as a target for cancer intervention.
authors: H. Lee Moffitt Cancer Center, University of South Florida, Tampa, Florida 33612, USA.
authors: M Y
authors: MY
authors: Alfonso-De Matte
authors: J Q
authors: JQ
authors: Cheng
authors: P A
authors: PA
authors: Kruk
mesh_terms: D004121:Dimethyl Sulfoxide / Q000494:pharmacology; D004847:Epithelial Cells / Q000201:enzymology* / Q000473:pathology; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects* / Q000528:radiation effects*; D006801:Humans; D010051:Ovarian Neoplasms / Q000201:enzymology* / Q000473:pathology; D010053:Ovary / Q000201:enzymology* / Q000473:pathology; D019098:Telomerase / Q000096:biosynthesis*; D014158:Transcription, Genetic / Q000187:drug effects / Q000528:radiation effects; D014407:Tumor Cells, Cultured; D014466:Ultraviolet Rays
chemical_list: D019098:Telomerase; D004121:Dimethyl Sulfoxide