A major problem in cancer treatment is the development of resistance to chemotherapeutic agents in tumor cells. Detection of effective prognostic biomarkers and targets are of crucial importance to the management of individualized therapies. However, quantitative analysis of the drug resistance gene had been difficult because of technical limitations. In this study, we designed and used a special hairpin deoxyribonucleic acid (DNA), which served as a beacon for detecting human drug resistance indicater. Upon hybridizing with the target mRNA, the hairpin DNA modified gold nanoparticle beacons (hDAuNP beacons) release the fluorophores attached at 5’end of the oligonucleotide sequence. The fluorescence properties of the beacon before and after the hybridization with the complementary DNA were confirmed in vitro. The hDAuNP beacons could be taken up by living cells with low inherent cytotoxicity and higher stability. hDAuNP beacon imaged by confocal laser scanning microscopy to detect the resistance gene expression. The detected fluorescence in MCF7and MCF7/ADR cells correlates with the specific drug resistance gene expression, which is consistent with the result from Q-PCR. Thus, this approach overcame many of the challenges of previous techniques by creating highly sensitive and effective intracellular probes for monitoring gene expression.

Date Published: 17 September 2014
PDF: 9 pages
Proc. SPIE 9230, Twelfth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2014), 92301U (17 September 2014); doi: 10.1117/12.2068780

Published in SPIE Proceedings Vol. 9230:
Twelfth International Conference on Photonics and Imaging in Biology and Medicine (PIBM 2014)
Qingming Luo; Lihong V. Wang; Valery V. Tuchin, Editor(s)