Telomerase activity in surgical specimens and fine-needle aspiration biopsies from hyperplastic and neoplastic human thyroid tissues

Trulsson, Lena; Velin, Asa K.; Herder, Anders; Söderkvist, Peter; Rüter, Anders; Smeds, Staffan

doi:10.1016/s0002-9610(03)00119-3

Cited by 14 publications

(11 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Telomerase activity was quantified using the real-time polymerase chain reaction-based Quantitative Telomerase Detection (QTD) Kit (Allied Biotech, Ijamsville, MD, USA) 19, 20 according to the manufacturer's protocol. Briefly, the CD34+ cells from the blood were collected, washed in PBS, and centrifuged for 30 minutes at 12 000×g at 4°C.…”

Section: Methodsmentioning

confidence: 99%

Regulation of Circulating Progenitor Cells in Left Ventricular Dysfunction

Boilson

Larsen

Harbuzariu

et al. 2010

Circ: Heart Failure

View full text Add to dashboard Cite

Background Reductions in numbers of circulating progenitor cells (CD34+ cell subsets) have been demonstrated in patients at risk for, or in the presence of, cardiovascular disease. The mediators of these reductions remain undefined. To determine whether neurohumoral factors might regulate circulating CD34+ cell subsets in vivo, we studied complementary canine models of left ventricular (LV) dysfunction. Methods and Results A pacing model of severe LV dysfunction and a hypertensive renal wrap (RW) model in which dogs were randomized to receive deoxycorticosterone acetate (DOCA) were studied. Circulating CD34+ cell subsets including hematopoietic precursor cells (HPCs:CD34+/CD45dim/VEGFR2-) and endothelial progenitor cells (EPCs:CD34+/CD45-/VEGFR2+) were quantified. Additionally, the effect of mineralocorticoid excess on circulating progenitor cells in normal dogs was studied. The majority of circulating CD34+ cells expressed CD45 dimly and did not express VEGFR2, consistent with an HPC phenotype. HPCs were decreased in response to pacing, and this decrease correlated with plasma aldosterone levels (Spearman Rank correlation = -0.67, p=0.03). In the RW model, administration of DOCA resulted in decreased HPCs. No changes were seen in EPCs in either model. Normal dogs treated with DOCA exhibited a decrease in HPCs in peripheral blood but not bone marrow associated with decreased telomerase activity. Conclusions This is the first study to demonstrate that mineralocorticoid excess, either endogenous or exogenous, results in reduction in HPCs. These data suggest that mineralocorticoids may induce accelerated senescence of progenitor cells leading to their reduced survival and decline in numbers.

show abstract

Section: Methodsmentioning

confidence: 99%

Regulation of Circulating Progenitor Cells in Left Ventricular Dysfunction

Boilson

Larsen

Harbuzariu

et al. 2010

Circ: Heart Failure

View full text Add to dashboard Cite

show abstract

“…Others have reported that the TA activity from cytological specimens from thyroid aspiration biopsy is less than that from tissue samples, and also that the TA enzyme itself may be sensitive to temperature fluctuations and may be easily degraded by proteinase and nuclease [31]. In clinically less aggressive papillary thyroid carcinoma which has low TA activity, or negative alternative lengthening of telomeres [32], colloid protein in the test sample may lead to an increased risk for false-negative results [33] Whether or not these effects have crucial consequences, thyroid tissue specimens seem to have less TA expression.…”

Section: Discussionmentioning

confidence: 99%

Thyroglobulin may affect telomerase activity in thyroid follicular cells

Nagasaka

Oda

Nakai

et al. 2009

Journal of Enzyme Inhibition and Medicinal Chemistry

View full text Add to dashboard Cite

Telomerase (TA) activity is known to be present in malignant tumor cells, but not in most somatic differentiated cells. TA shows relatively high activity in thyroid cancer cells, but reports vary. This fact prompted us to elucidate whether cell component inhibitors of TA in the thyroid follicles can modulate its activity. The activity of TA extracted from Hela cells was inhibited by mixing with the supernatant fraction of human thyroid tissue extract. To examine the effect of iodine, thyroid hormones ('-T3 and '-T4) and human thyroglobulin (hTg) contained in the thyroid follicles, '-T3, '-T4 and hTg were added to the TRAP assay system in vitro, using TA from Hela cells. Iodine, '-T3 and '-T4 did not affect TA activity, but hTg inhibited the TA activity in a dose-dependent manner (IC 50 of hTg: ca 0.45 mM: inhibiting concentration of hTg was from 0.15 mM to 3.0 mM). The hTg inhibition was not evident in the RT-PCR system, suggesting no effect of hTg on Taq DNA polymerase activity. The hTg inhibition of TA activity was attenuated by dNTP but not significantly by TS primer. These data suggest that hTg contained in thyroid follicular cells of various thyroid diseases may affect the TA activity measured in biopsied thyroid specimens, and that the reduction of the TA activity by hTg may induce slow progression and growth, and low grade malignancy of thyroid cancer, particularly differentiated carcinoma.

show abstract

“…These cells have been shown to be telomerase positive [11,59] which has given rise to false positives in several clinical studies [7,12,36,50,56,60,61]. Magnetic beads have been used in either positive (human epithelial antigen positive cells) or negative (CD45 positive cells) selection to separate epithelial cancer cells from activated lymphocytes and blood-related products.…”

Section: Discussionmentioning

confidence: 99%

A novel magnetic bead‐based assay with high sensitivity and selectivity for analysis of telomerase in exfoliated cells from patients with bladder and colon cancer

Rothacker

Ramsay²,

Ciznadija

et al. 2007

Electrophoresis

View full text Add to dashboard Cite

Telomerase activity is elevated in more than 85% of cancer cells and absent in most of the normal cells and thus represents a potential cancer biomarker. We report its measurement in colon and bladder cancer cells captured using antibody-coated magnetic beads. The cells are lysed and telomerase activity is detected using a biosensor assay that employs an oligonucleotide containing the telomerase recognition sequence also covalently coupled to magnetic beads. Telomerase activity is measured by the incorporation of multiple biotinylated nucleotides at the 3'-end of the oligonucleotide strands during elongation which are then reacted with streptavidin-conjugated horseradish peroxidase. A luminescent signal is generated when hydrogen peroxidase is added in the presence of luminol and a signal enhancer. LOD experiments confirm sensitivity down to ten cancer cell equivalents. The telomerase assay reliably identified patient samples considered by an independent pathological review to contain cancer cells. Samples from normal healthy volunteers were all telomerase negative. The assay, which is amenable to automation, demonstrated high sensitivity and specificity in a small clinical cohort, making it of potential benefit as a first line assay for detection and monitoring of colon and bladder cancer.

show abstract

Telomerase activity in surgical specimens and fine-needle aspiration biopsies from hyperplastic and neoplastic human thyroid tissues

Cited by 14 publications

References 22 publications

Regulation of Circulating Progenitor Cells in Left Ventricular Dysfunction

Regulation of Circulating Progenitor Cells in Left Ventricular Dysfunction

Thyroglobulin may affect telomerase activity in thyroid follicular cells

A novel magnetic bead‐based assay with high sensitivity and selectivity for analysis of telomerase in exfoliated cells from patients with bladder and colon cancer

Contact Info

Product

Resources

About