AB091. Establishment and application of brainstem glioma organoids.

BACKGROUND: Traditional preclinical experiments on brainstem gliomas mainly rely on patient-derived primary cell lines, but there are problems such as low success rate in establishment and inability to preserve tumor heterogeneity, which limit the clinical transformation. As a new type of in vitro tumor model, organoids have similar structure and function to the original tumor, requiring less tissue for cultivation, with short cycle and high success rate, which is particularly suitable for brainstem glioma biopsy. There is currently no precedent for the successful construction of brainstem glioma organoid models. This new established organoid provides us a more robust preclinical tool for comprehending the pathogenesis and conducting drug screening for this kind of disease.

METHODS: Cultivate patient-derived brainstem glioma organoids in vitro, verify the genetic fidelity and consistency of the organoids through morphological experiments as well as sequencing technology. Then explore the evolutionary direction of multiple types of brainstem gliomas through pseudo-time series analysis. Complete drug screening, natural killer (NK) cell co-culture, oncolytic virus therapy, and other treatments based on organoids in vitro, and evaluate the efficacy. Complete co-culture of organoids and Institute of Cancer Research (ICR) mouse brain slices in vitro. Establish patient-derived organoid xenograft (PDOX) mouse models derived from organoids in vivo.

RESULTS: The establishment of organoids of all types of brainstem gliomas was completed for the first time in the world, with a total of 41/48 organoid models derived from patients, with a success rate of 85.4%, covering all segments and pathological types. The results of morphological experiments and sequencing showed that the genetic characteristics of organoids were highly consistent with those of tumor tissues. Drug screening tests for temozolomide and panobinostat were completed in vitro, and NK cell co-culture and oncolytic virus therapy testing were achieved. Co-culture of brainstem glioma organoids and mouse brain slices was achieved in vitro. Furthermore, a PDOX model of brainstem glioma was established.

CONCLUSIONS: Brainstem glioma organoids can be established maturely, stably, and reliably, and can be used for preclinical drug testing for patients. Animal models derived from brainstem glioma organoids have broad preclinical experimental value.