MODL-03. THERAPEUTIC EFFICACY OF IMIPIRIDONES IN LYNCH SYNDROME-ASSOCIATED GLIOMAS

Abstract

Abstract INTRODUCTION Lynch Syndrome, a hereditary cancer syndrome linked to DNA mismatch repair gene mutations (MMRD), predisposes individuals to various cancers, including high grade gliomas (Lynch-HGG). Effective treatments for Lynch-HGGs are scarce, and suitable pre-clinical models are needed to identify novel therapeutic combinations. METHODS In this study, we generated patient-derived cell line models of Lynch-HGGs (n=3), characterized them through Western blot analysis for MMRD gene markers, and conducted genome and transcriptomic analyses. Murine models were then generated via intracranial injection of cultured cells expressing mCherry-luciferase reporter genes. Drug screening based on transcriptomic analysis was performed to identify potential therapeutic agents. RESULTS Our findings showed loss of MMRD protein consistent with the primary mutation, and a constant loss of P53, a tumor suppressor protein. One cell line, 7316-3058, exhibited an absence of NF1 expression, another critical tumor suppressor protein. Transcriptomic analysis unveiled upregulation in cell cycle processes and SUMOylation of DNA damage response and repair proteins. In vitro treatment with imipiridone compounds (ONC201 and ONC206) demonstrated varying degrees of drug response, with 7316-3058 displaying high sensitivity to the targeted inhibitor. Unfortunately, this therapeutic efficacy did not translate to the in vivo murine model, suggesting underlying mechanisms that impede drug efficiency. CONCLUSION In summary, we developed effective pre-clinical models of Lynch-HGG that can be used to screen different drug combinations targeted to treat these tumors. Furthermore, despite promising in-vitro data, we demonstrated the limited efficacy of imipiridones in treating Lynch-HGG in vivo, emphasizing the challenges in translating in vitro findings to in vivo contexts. This study contributes valuable insights to the development of effective therapeutic strategies for Lynch Syndrome-associated gliomas.