title: Measurement of telomerase activity in dog tumors.
abstract: Telomeres are specific structures present at the end of liner chromosomes. DNA polymerase can not synthesize the end of liner DNA and, as a result, the telomeres become progressively shortened by successive cell divisions. To overcome the end replication problem, telomerase adds new telomeric sequences to the end of chromosomal DNA. The enzyme activity is undetectable in most normal human adult somatic cells, in which shortening of the telomere is thought to limit the somatic-cell life span. In contrast to normal somatic cells, many human tumors possess telomerase activity. The present study looked at whether telomerase activity might serve as a marker for canine tumors. Telomerase activity was measured using the telomeric repeat amplification protocol assay. Normal dog somatic tissues showed little or no telomerase activity, while normal testis exhibited a high level of telomerase activity. We measured telomerase activity in tumor samples from 45 dogs; 21 mammary gland tumors, 16 tumors developed in the skin and oral cavity, 7 vascular tumors and 1 Sertoli cell tumor. Greater than 95% of the tumor samples contained telomerase activity (3-924 U/2 micrograms protein). The results obtained in this study indicated that telomerase should be a useful diagnostic marker for a variety of dog tumors, and it may serve as a target for antitumor chemotherapy.
authors.affiliation: Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, University of Tokyo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yazawa
authors.forename: M
authors.initials: M
authors.lastname: Okuda
authors.forename: A
authors.initials: A
authors.lastname: Setoguchi
authors.forename: R
authors.initials: R
authors.lastname: Nishimura
authors.forename: N
authors.initials: N
authors.lastname: Sasaki
authors.forename: A
authors.initials: A
authors.lastname: Hasegawa
authors.forename: T
authors.initials: T
authors.lastname: Watari
authors.forename: H
authors.initials: H
authors.lastname: Tsujimoto
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000662:veterinary; D000236:Adenoma / Q000201:enzymology / Q000662:veterinary; D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis*; D002277:Carcinoma / Q000201:enzymology / Q000662:veterinary; D002280:Basal Cell Carcinoma / Q000201:enzymology / Q000662:veterinary; D002294:Carcinoma, Squamous Cell / Q000201:enzymology / Q000662:veterinary; D017931:DNA Primers / Q000737:chemistry; D004283:Dog Diseases / Q000175:diagnosis* / Q000201:enzymology; D004285:Dogs; D004587:Electrophoresis, Agar Gel / Q000662:veterinary; D006393:Hemangiopericytoma / Q000201:enzymology / Q000662:veterinary; D006394:Hemangiosarcoma / Q000201:enzymology / Q000662:veterinary; D008297:Male; D015674:Mammary Neoplasms, Animal / Q000201:enzymology; D009062:Mouth Neoplasms / Q000201:enzymology / Q000662:veterinary; D009369:Neoplasms / Q000175:diagnosis / Q000201:enzymology / Q000662:veterinary*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D012878:Skin Neoplasms / Q000201:enzymology / Q000662:veterinary; D019098:Telomerase / Q000032:analysis*; D013736:Testicular Neoplasms / Q000201:enzymology / Q000662:veterinary; D019043:Vascular Neoplasms / Q000201:enzymology / Q000662:veterinary
chemical_list: D014408:Biomarkers, Tumor; D017931:DNA Primers; D019098:Telomerase