Label-free detection of telomerase activity using guanine electrochemical oxidation signal

Date

2007-11-15

Author

Eskiocak, Ugur
Ozkan-Ariksoysal, Dilsat
Ozsoz, Mehmet
Öktem, Hüseyin Avni

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

137
views

0
downloads

Telomerase is an important biomarker for cancer cells and its activation in 85% of all cancer types confers a clinical diagnostic value. A label-free electrochemical assay based on guanine oxidation signal to measure telomerase activity is described. This developed technology combined with a disposable sensor, carbon graphite electrode (CGE), and differential pulse voltammetry (DPV) was performed by using PCR amplicons with/without telomeric repeats as the guanine oxidation signal observed at +1.0 V measured after the immobilization of PCR products. Guanine oxidation signal was chosen as a measure of telomerase activity because a substantial increase in the number of guanines was introduced by the action of telomerase which adds hexameric repeats (TTAGGG)(n) that contain 50% guanine. The developed assay was shown to specifically measure telomerase activity from cell extracts, and elongation rates increased linearly in a concentration dependent manner. Telomerase activity could be detected in cell extracts containing as low as 100 ng/mu L of protein. All of the electrochemical measurements were also confirmed with the conventional TRAP-silver staining assay. Rapidity, simplicity, and the label-free nature of the developed assay make it suitable for practical use in quantitative determination of telomerase activity from clinical samples for diagnosis of cancer.

Subject Keywords

Analytical Chemistry

URI

https://hdl.handle.net/11511/45989

Journal

ANALYTICAL CHEMISTRY

DOI

https://doi.org/10.1021/ac071014r

Collections

Department of Biology, Article

Suggestions

OpenMETU
Core

Label-free enrichment of MCF7 breast cancer cells from leukocytes using continuous flow dielectrophoresis Arslan, Zeynep Caglayan; Yalcin, Yagmur Demircan; Külah, Haluk (2022-04-01) Circulating tumor cells (CTCs) present in the bloodstream are strongly linked to the invasive behavior of cancer; therefore, their detection holds great significance for monitoring disease progression. Currently available CTC isolation tools are often based on tumor-specific antigen or cell size approaches. However, these techniques are limited due to the lack of a unique and universal marker for CTCs, and the overlapping size between CTCs and regular blood cells. Dielectrophoresis (DEP), governed by the in...
Acyl chain length and charge effect on Tamoxifen-lipid model membrane interactions Bilge, Duygu; KAZANCI, NADİDE; Severcan, Feride (Elsevier BV, 2013-05-22) Tamoxifen (TAM), which is an antiestrogenic agent, is widely used during chemotherapy of breast, pancreas, brain and liver cancers. In this study, TAM and model membrane interactions in the form of multilamellar vesicles (MLVs) were studied for lipids containing different acyl chain length and different charge status as a function of different TAM (1, 6, 9 and 15 mol%) concentrations. Zwitterionic lipids namely dipalmitoyl phosphatidylcholine (DPPC), and dimyristoylphosphatidylcholine (DMPC) lipids were use...
Development of a solid-phase microextraction LC-MS/MS method for determination of oxidative stress biomarkers in biofluids Kahremanoglu, Kubra; Temel, Ezgi Rana; Korkut, Tamara Ecem; Nalbant, Atakan Arda; Baştuğ Azer, Bersu; Durucan, Caner; Volkan, Mürvet; Boyacı, Ezel (Wiley, 2020-04-03) Recently the connection between oxidative stress and various diseases, including cancer and Alzheimer's, attracts notice as a pathway suitable for diagnostic purposes. 8-Oxo-deoxyguanosine and 8-oxo-deoxyadenosine produced from the interaction of reactive oxygen species with DNA become prominent as biomarkers. Several methods have been developed for their determination in biofluids, including solid-phase extraction and enzyme-linked immunosorbent assays. However, still, there is a need for reliable and fast...
Comprehensive native glycan profiling with isomer separation and quantitation for the discovery of cancer biomarkers Hua, Serenus; An, Hyun Joo; Özcan Kabasakal, Süreyya; Ro, Grace S.; Soares, Stephanie; DeVere-White, Ralph; Lebrilla, Carlito B. (Royal Society of Chemistry (RSC), 2011-01-01) Glycosylation is highly sensitive to the biochemical environment and has been implicated in many diseases including cancer. Glycan compositional profiling of human serum with mass spectrometry has already identified potential biomarkers for several types of cancer and diseases; however, composition alone does not fully describe glycan stereo-and regioisomeric diversity. The vast structural heterogeneity of glycans presents a formidable analytical challenge. We have developed a method to identify and quantif...
Isomer-specific chromatographic profiling yields highly sensitive and specific potential N-glycan biomarkers for epithelial ovarian cancer Hua, Serenus; Williams, Cynthia C.; Dimapasoc, Lauren M.; Ro, Grace S.; Özcan Kabasakal, Süreyya; Miyamoto, Suzanne; Lebrilla, Carlito B.; An, Hyun Joo; Leiserowitzf, Gary S. (Elsevier BV, 2013-03-01) Aberrant glycosylation has been observed for decades in essentially all types of cancer, and is now well established as an indicator of carcinogenesis. Mining the glycome for biomarkers, however, requires analytical methods that can rapidly separate, identify, and quantify isomeric glycans. We have developed a rapid-throughput method for chromatographic glycan profiling using microfluidic chip-based nanoflow liquid chromatography (nano-LC)/mass spectrometry. To demonstrate the utility of this method, we ana...

Citation Formats

U. Eskiocak, D. Ozkan-Ariksoysal, M. Ozsoz, and H. A. Öktem, “Label-free detection of telomerase activity using guanine electrochemical oxidation signal,” ANALYTICAL CHEMISTRY, pp. 8807–8811, 2007, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/45989.