Abstract 1445: A nuclear localizing peptide that targets glioblastoma

Abstract Glioblastoma (GBM) is one of the most aggressive and fatal primary brain neoplasms with a median survival of less than 15 months even after current standard of cares including surgical resection, radiotherapy and systemic therapy. Although systemic anticancer agents, such as temozolomide, are used as the standard of care for GBM, therapeutic efficacy is limited due to the off-target systemic toxicity of traditional chemotherapeutics. Targeted systemic therapy is emerging as an important treatment strategy for cancer therapy. Phage display peptide library was used to discover peptides that undergo endocytosis in GBM. We have identified a novel peptide that accumulates intracellularly in multiple GBM cell lines. Intracellular localization was quantified by FACS analysis of the FITC-labeled peptide. As compared to untreated GBM cells, D54, U251 and SF295 human GBM cell lines treated with 5.55 µM of peptide-FITC conjugate showed a significant FITC-positive shift on FACS analysis with 83%, 85% and 71% of cells internalizing the peptide, respectively. Confocal laser scanning microscopy experiments further confirm the intracellular targeting of the FITC-peptide in D54, U251 and SF295 GBM cell lines with associated peptide nuclear localization. Further studies are underway to elucidate the microscopic biodistribution of the nuclear homing peptide (NHP) in GBM mouse models. This work is significant as a novel cell surface, intracellular or nuclear binding partner may be identified for peptide-targeted cancer drug therapy. Furthermore, the NHP has potential to be translated to the clinic as targeted therapy for GBM patients in the form of a peptide-drug conjugate. Citation Format: Calvin D. Lewis, Abhay Singh, Vaishali Kapoor, Dennis E. Hallahan. A nuclear localizing peptide that targets glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1445.