American Association for Cancer Research
10780432ccr190955-sup-219416_2_table_5712334_pw8w3n.docx (28.41 kB)

Supplementary Table S2 from Mechanisms and Antitumor Activity of a Binary EGFR/DNA–Targeting Strategy Overcomes Resistance of Glioblastoma Stem Cells to Temozolomide

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journal contribution
posted on 2023-03-31, 21:09 authored by Zeinab Sharifi, Bassam Abdulkarim, Brian Meehan, Janusz Rak, Paul Daniel, Julie Schmitt, Nidia Lauzon, Kolja Eppert, Heather M. Duncan, Kevin Petrecca, Marie-Christine Guiot, Bertrand Jean-Claude, Siham Sabri

Table S2 summarizes IC50s of TMZ, gefitinib or ZR2002 for various GSCs.


Canadian Cancer Society Research Institute

Cancer Research Society



Glioblastoma (GBM) is a fatal primary malignant brain tumor. GBM stem cells (GSC) contribute to resistance to the DNA-damaging chemotherapy, temozolomide. The epidermal growth factor receptor (EGFR) displays genomic alterations enabling DNA repair mechanisms in half of GBMs. We aimed to investigate EGFR/DNA combi-targeting in GBM. ZR2002 is a “combi-molecule” designed to inflict DNA damage through its chlorethyl moiety and induce irreversible EGFR tyrosine kinase inhibition. We assessed its in vitro efficacy in temozolomide-resistant patient-derived GSCs, mesenchymal temozolomide-sensitive and resistant in vivo–derived GSC sublines, and U87/EGFR isogenic cell lines stably expressing EGFR/wild-type or variant III (EGFRvIII). We evaluated its antitumor activity in mice harboring orthotopic EGFRvIII or mesenchymal TMZ-resistant GSC tumors. ZR2002 induced submicromolar antiproliferative effects and inhibited neurosphere formation of all GSCs with marginal effects on normal human astrocytes. ZR2002 inhibited EGF-induced autophosphorylation of EGFR, downstream Erk1/2 phosphorylation, increased DNA strand breaks, and induced activation of wild-type p53; the latter was required for its cytotoxicity through p53-dependent mechanism. ZR2002 induced similar effects on U87/EGFR cell lines and its oral administration significantly increased survival in an orthotopic EGFRvIII mouse model. ZR2002 improved survival of mice harboring intracranial mesenchymal temozolomide-resistant GSC line, decreased EGFR, Erk1/2, and AKT phosphorylation and was detected in tumor brain tissue by MALDI imaging mass spectrometry. These findings provide the molecular basis of binary EGFR/DNA targeting and uncover the oral bioavailability, blood–brain barrier permeability, and antitumor activity of ZR2002 supporting potential evaluation of this first-in-class drug in recurrent GBM.