Test for Telomerase Activity

About

High activity of the enzyme telomerase in cells indicates the uncontrolled proliferation of cells. As this is a characteristic of cancer cells, this biomarker can be used as a cancer diagnostic tool. Many of the current-ly available telomerase activity assays are based on the telomeric repeat amplification protocol (TRAP). However, this TRAP method requires whole protein extraction from tissue or cells, which can leave impurities behind, adversely affecting the diagnostic results. Another challenge with TRAP is the possibility of non-specific binding which may lead to false positives. Additionally, TRAP assays can be very costly and time consuming. There is therefore a need for a faster and cheaper alternative. Wits researchers have developed a telomerase assay kit for detecting telomerase activity in cells using functionalized gold nanoparticles (AuNPs). In addition, the researchers have developed a method for producing these gold nanoparticles, which are functionalized with a thiolated telomerase substrate. The detection technique utilized is that of a colorimetric analysis; whereby the activity of the telomerase enzyme determines the proximity of the gold nanoparticles to each other. The nanoparticles change the colour of the solution depending on this proximity, and thus provide information regarding the presence of cancerous cells. This method is quite sensitive as even a small change in telomerase activity, and therefore in gold nanoparticle size, could result in an observable colour change. This sensitivity, as well as the ability to be easily functionalized using different molecules, could make AuNPs a very useful biosensor in detecting telomerase activity, and ultimately diagnosing cancer.