33P - The screening and characterization of aptamer against gefitinib-resistant cells

Date 07 May 2017
Event ELCC 2017
Session Poster Display Session
Topics Immunotherapy
Thoracic malignancies
Therapy
Presenter Yuh-Ling Chen
Citation Annals of Oncology (2017) 28 (suppl_2): ii9-ii13. 10.1093/annonc/mdx089
Authors Y. Chen, J. Wu, T. Hong
  • National Cheng Kung University, 70101 - Tainan/TW

Abstract

Background

The EGFR tyrosine kinase inhibitor (TKI) gefitinib serves as first-line drug for patients with advanced non-small cell lung cancer (NSCLC) harboring EGFR mutation. The challenge of this target therapy is the acquired resistance due to T790M mutation after gefitinib treatment. Aptamers are single-strand DNA molecules that form 3D structures and specifically bind to target components. In this study, we wanted to isolate aptamers with recognition ability for gefitinib-resistant NSCLC cells and look for another mechanism that contributes to the acquired resistance that is not caused by T790M mutation.

Methods

We used PC9 (gefitinib-sensitive cells) and PC9-IR (gefitinib-resistant cells with no T790M mutation) cells to select specific aptamers that bound to membrane proteins which were overexpressed in PC9-IR cells. We used suction-type microfluidic control module to perform cell-systematic evolution of ligands by exponential enrichment (Cell-SELEX) and obtained some aptamers that had more affinity to bind to PC9-IR. We examined the specificity of the aptamers and observed whether aptamers could bind to cell membranes of PC9-IR. In addition, we tested the cell cytotoxicity of the aptamers.

Results

We obtained the aptamer, AP16-23F, which had greater affinity to bind to PC9-IR. In order to test whether AP16-23F could recognize the cells with gefitinib resistance, we used AP16-23F to isolate cells from PC9 by fluorescence-activated cell sorting (FACS). The results showed that the cells selected by AP16-23F were more resistant to gefitinib.

Conclusions

We have isolated an aptamer with specificity for binding and capturing gefitinib-resistant NSCLC cells. This aptamer may be useful for drug resistance detection and may have the potential to deliver anti-cancer drug to gefitinib-resistant cells in the future.

Clinical trial identification

Legal entity responsible for the study

National Cheng Kung University

Funding

Ministry of Science and Technology, Taiwan

Disclosure

All authors have declared no conflicts of interest.