*2.7. In Vivo Xenograft Model*

A tumor sample from a GBM patient with TMZ resistance was used to establish the TMZ-resistant mouse model for in vivo evaluation according to previously established protocols [15]. In brief, NOD/SCID mice were anaesthetized (10 mg/kg, ketamine/xylazine and buprenorphine, 0.05 mg/kg, before and after injection). TMZ-resistant LN18 GBM cells (5 <sup>×</sup> 105 cells) were stereotactically injected into the right striata of the mice. One week postinjection, the mice were randomly divided into vehicle, pacritinib (100 mg/kg, five times/week), TMZ (30 mg/kg, five times/week), or the combination of pacritinib (100 mg/kg) and TMZ (30 mg/kg) groups. Both drugs were administered via oral gavage. Mice were humanely sacrificed by sodium pentobarbital at the end of the experiments. The tumor presence and size were determined in the mice via necropsy and cranial dissection. Tumor samples were harvested for further analysis. The tumor size (average area) was determined from cross sections of the tumor samples. Image J software was used for calculating the tumor size. The animal study protocol was approved by the Animal Care and User Committee at Taipei Medical University (Affidavit of Approval of Animal Use Protocol# Taipei Medical University—LAC-2017-0512).
