Telomerase is an enzyme that maintains telomere length by adding telomeric sequence repeats onto chromosome ends. The telomerase ribonucleoprotein complex consists of two essential components, a reverse transcriptase and an RNA molecule that provides the template for telomeric repeat synthesis. A common secondary structure of vertebrate telomerase RNA has been proposed based on a phylogenetic c...

The correlation between telomerase activity, telomere lengths, and cellular replicative capacity has led to the theory that maintenance of telomere lengths by telomerase acts as a molecular clock to control replicative capacity and senescence. Regulation of this molecular clock may have applications in the treatment of cell aging and tumorigenesis, although little is presently known about the r...

Telomerase activation plays a crucial role in the immortalization of human cells and carcinogenesis; however, the temporal and pathophysiological aspects of the activation in vivo are poorly understood. We found telomerase activity not only in malignant tumors (91%) but also in most benign (60%) and premalignant (89%) skin tumors. This suggests the involvement of telomerase activation in a cruc...

Telomere studies in carcinomas have been extensively reported for prognostic utility and effective methods for targeting telomerase therapy has been described, but efficacy of telomerase inhibitor remained unknown in sarcoma cells. In this study, we investigated the effects of telomerase inhibitor cationic porphyrin TMPyP4 on telomerase activity, telomere length, cell growth, and apoptosis in o...

We have identified telomerase activity in extracts of three evolutionarily diverse kinetoplastid species: Trypanosoma brucei, Leishmania major, and Leishmania tarentolae. Telomerase activity was initially detected in extracts from insect form cells of all three kinetoplastid species by using a modification of the one-tube telomere repeat amplification protocol [Kim, N., et al. (1994) Science 26...

Telomerase has been recognized as a common factor in most tumor cells, and in turn a distinctive feature with respect to non-malignant cells. This feature has made telomerase a promising target for cancer therapy. Telomerase studies revealed that it is a multi-subunit complex possessing different levels of regulation, including control of expression, phosphorylation state, assembly and transpor...

carcinogenesis is a multistep process characterized by the gradual accumulation of genetic changes that ultimately lead to cancer. these genetic mutations can impart limitless replicative potential to the cancer cells making them immortal. telomeres are repeat nucleotide sequence ttaggg that are present at the end of chromosomes. its functions are to protect the chromosomal ends and to ensure t...

Telomerase plays a significantly important role in keeping the telomere length of a chromosome. Telomerase overexpresses in nearly all tumor cells, suggesting that telomerase could be not only a promising biomarker but also a potential therapeutic target for cancers. Therefore, numerous efforts focusing on the detection of telomerase activity have been reported from polymerase chain reaction (P...

Human uterine endometrium undergoes a complex pattern of changes in proliferation and secretory activity during the menstrual cycle. In the present study, telomerase activity in normal endometrium was examined using a non-radioisotope PCR-based telomeric repeat amplification protocol assay. Various levels of telomerase activity were detected in the 60 normal endometrial samples examined, depend...

INTRODUCTION Telomerase repairs the telomeric ends of chromosomes and is active in nearly all malignant cells. Hepatitis C virus (HCV) is known to be oncogenic and potential interactions with the telomerase system require further study. We determined the effects of HCV infection on human telomerase reverse transcriptase (TERT) expression and enzyme activity in primary human hepatocytes and cont...