Research shows that human cells can undergo only a certain number of divisions in vitro until the DNA telomeric ends are successively selleck bio shortened with every cell division [12]. In some cases senescence is selleck chem overcome in the cell by carcinogen or virus-induced transformation, a complex process, which results in altered morphology and growth properties [16]. Most of the changed cells cease to divide and die, thus become immortal [17-19]. Telomerase activity was detected in unicellular eukaryotes, and it was considered to be responsible for the stability of telomere length [16-23]. Further early 1990s research Inhibitors,Modulators,Libraries on human cells, connected telomerase activity and held it responsible for the proliferation of human cancer cells [24].
Thus increased telomerase activity can provide important qualitative and quantitative results for cancer studies [24].
Its detection has been determined using various bioanalytical assays and techniques.The very first detections of telomerase were direct Inhibitors,Modulators,Libraries telomerase activity assays, which included an oligonucleotide (as a substrate for the elongation process of telomerase), a cell extract, and a deoxynucleotide triphosphate (dNTP) mixture [25]. Using end-labeled substrate oligonucleotides Inhibitors,Modulators,Libraries or by incorporation of radioactive dNTP precursors, the activity of telomerase was analyzed [25-26]. This technique suffered from sensitivity problems. To measure the telomerase activity more affectively, a lot of the radioactive precursors had to be used [25-26]; this makes it unfavorable for routine use.
An alternative method, which increased Inhibitors,Modulators,Libraries Inhibitors,Modulators,Libraries the sensitivity of telomerase for its detection, Inhibitors,Modulators,Libraries was proposed by Kim et al [8], and is known as the telomeric repeat amplification protocol (TRAP). The ribonucleoprotein enzyme telomerase uses its RNA as a template for the synthesis of TTAGGG repeats at the end of the chromosomes [20-22]. After each TTAGGG repeat unit, telomerase pauses to reposition on its internal RNA template before it synthesizes the next repeat [21].The generated ladder consists of 6 nucleotide units at a given time. The added repeat units by telomerase can be analyzed by using PCR amplification Inhibitors,Modulators,Libraries which uses the telomerase substrate (TS) oligonucleotide as the forward primer, and an oligonucleotide which is able to anneal to the telomeric repeats (CX) as the reverse primer [8].
A recent review article published by Fajkus Inhibitors,Modulators,Libraries [27] summaries the TRAP Batimastat technique and its Dacomitinib limitations.
www.selleckchem.com/products/brefeldin-a.html A number of modified TRAP techniques were developed to account for its drawbacks [24-33]. Recent developments in bioelectronics and bionanotechnology [37-50] result in novel analytical procedures allowing the analysis of telomerase activity with an extremely blog of sinaling pathways high sensitivity without the TRAP assay or the PCR step. The present review paper is aimed to give a short overview of these novel methods.2.