Telomerase activity in malignant ovarian tumors with deregulation of cell cycle regulatory proteins.
Using a semiquantitative telomeric repeat amplification protocol assay, telomerase-positive frequencies and enzyme levels were measured. Out of 95% of 49 human ovarian tumors, the highest level of telomerase activity was observed in malignant tumors. Furthermore, by immunohistochemical staining of cell cycle regulatory proteins (pRB, p16, cyclin D1, cyclin E and p53) at the G1 checkpoint, we evaluated the relation between each protein alterations and the levels of telomerase activity. We could not demonstrate a clear relation with each molecule except for cyclin E, but suggesting that aberrant accumulation of these proteins was considered as a reason for telomerase deregulation, which may play an essential role in the pathway of telomerase regulation.
Terasawa
K
K
Department of Obstetrics and Gynecology, Sapporo Medical University, School of Medicine, Hokkaido, Japan.
Sagae
S
S
Takeda
T
T
Ishioka
S
S
Kobayashi
K
K
Kudo
R
R
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018797:Cell Cycle Proteins / Q000378:metabolism*; D019938:Cyclin D1 / Q000032:analysis; D019927:Cyclin E / Q000032:analysis; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis; D005260:Female; D016193:G1 Phase; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D009367:Neoplasm Staging; D010051:Ovarian Neoplasms / Q000201:enzymology* / Q000473:pathology; D016133:Polymerase Chain Reaction / Q000379:methods; D019098:Telomerase / Q000378:metabolism*; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D018797:Cell Cycle Proteins; D019927:Cyclin E; D019941:Cyclin-Dependent Kinase Inhibitor p16; D016159:Tumor Suppressor Protein p53; D019938:Cyclin D1; D019098:Telomerase