Intrathecal Anti-cancer Drug Screening for Diffuse Midline Gliomas

Introduction: Diffuse midline gliomas (DMGs) have extremely poor survival rates and typically exhibit the H3K27M mutation, resulting in low chemotherapy response. DMGs often have a more intact blood-brain barrier, complicating drug delivery. While various methods (such as nasal delivery, convection-enhanced delivery, focused ultrasound, and nanobionic carriers) have been explored, the clinical transformation process remains lengthy. Intrathecal injection is one of the oldest and most mature techniques in neurosurgery. Therefore, we aim to screen drug therapies suitable for intrathecal injection using a new organoid model to simulate drug effects in cerebrospinal fluid and expedite the clinical transition.

Methods: Complete a literature review and search the MCE drug compound database for drugs previously used for clinical intrathecal injection. Establish primary cell lines with mutations including H3K27M in vitro and establish a human posterior brainstem cell line (hPPC) from aborted embryos. Conduct high-throughput (Cell-Titer) and high-content drug screening in these cell lines, performing visual pharmacomic analysis. Remove ineffective drugs to form the intrathecal potential anti-cancer drug library (ITAC). Develop DMG organoids and perform personalized drug screening to identify the most sensitive drugs.

Results: A compounds library for intrathecal use, consisting of 57 drugs deemed safe by prior clinical reports, was established. Five DMG primary cell lines, one H3 wild-type brainstem glioblastoma cell line, and one hPPC cell line were developed. In vitro, high-throughput drug screening and high-content verification were conducted. Ineffective narcotic analgesics and drugs harmful to hPPC were eliminated, leaving 41 drugs for the ITAC library. Six clinically used intrathecal drugs and one combination therapy were selected for high-content screening on organoids from H3K27M mutant DMG patients, ultimately identifying the most sensitive therapy.

Conclusion : We established a drug library of ITAC drugs suitable for central nervous system tumor screening. In this library, six clinically used intrathecal drugs and one combination therapy demonstrated potential efficacy in DMG, thereby shortening the clinical transformation process. Additionally, the use of organoids has enabled surrogate drug testing for patients. We are currently seeking applications to conduct corresponding clinical trials.