The growth rates of glioblastoma patient-derived xenografts vary widely. To help facilitate planning for experiments, the Mayo Clinic Brain Tumor Patient-Derived Xenograft National Resource has tabulated the approximate growth rates of each PDX line.
For flank tumors, these estimates are based on the frequency that flank tumors are passaged in the PDX National Resource colony. This time reflects the time for 100 microliters of mechanically disaggregated tumor tissue diluted 1:1 in reduced growth factor Matrigel to grow to IACUC limits of 2,000 mm3 volume.
Thus, the rate of tumor growth for a specific experiment would likely be different depending on the amount of cells, the handling of the cells when they're injected in the flank, and the size criteria for harvest.
For orthotopic tumors, short-term explant cultures that were developed from flank tumor tissue were trypsinized and counted. For this, 300,000 cells suspended in 3 microliters of saline were injected into the right basal ganglia.
For each PDX model, the median time to reach a moribund state is reported for a cohort of five to 10 mice with orthotopic tumors.