Poster Presentation 31st Lorne Cancer Conference 2019

Development of an EGFR aptamer for targeted glioblastoma treatment (#196)

Emma M Hays 1 , Sarah Shigdar 1 , Aaron Schultz 1
  1. Deakin University, Waurn Ponds, VICTORIA, Australia

Glioblastoma is a highly malignant primary brain tumour, which remains mostly incurable despite advances in cancer treatments. The current therapeutic modalities are associated with severe off target effects, and poor quality of life. Targeted therapeutics hold the promise of providing effective treatment against glioblastoma, without harming the healthy brain tissue, or the rest of the body. However, the use of antibodies to treat glioblastoma has proven to be clinically unsuccessful, and associated with immunotoxicity in some patients. Therefore, an alternative targeting method is required. Chemical antibodies, better known as aptamers, function similarly to antibodies by binding to their target via shape recognition. They can easily be modified to carry drug compounds, and their small size, specificity and low immunogenicity make them ideal drug delivery candidates. This study aimed to develop an aptamer targeting the epidermal growth factor receptor (EGFR), and to assess the efficacy of novel chemotherapeutic compounds in vitro. Specificity and sensitivity of the EGFR aptamers was observed through confocal microscopy and flow cytometry. The EGFR aptamers were found to internalise in the EGFR positive cells lines, and not in the EGFR negative cell lines. MTT assays and flow cytometry were used to assess the efficacy of the novel chemotherapeutic compounds. Significant decreases in cell viability were seen across all cell lines. These results indicate the drug compounds are capable of inhibiting cell growth, however, the drugs did not preferentially target the glioblastoma cell lines and therefore need to be used in conjunction with the EGFR aptamer to ensure their delivery directly to the tumour cells, to increase treatment efficacy and reduce the off-target effects associated with chemotherapy.