Abstract: Objective To establish a transplantable tumor strain of medulloblastoma in vivo from cell-line-derived xenograft (CDX) and to analyze the growth and pathological characteristics of the transplanted tumor model. Methods A previously established medulloblastoma cell line(PUMC-MB1) was utilized to construct CDX. The cultured cell suspension was injected into the right axilla of SCID mice subcutaneously with dosage as 5×10⁶ cells/mouse. The mice were sacrificed when the diameter of CDX reached around 1.5 cm. The xenografts were harvested and transplanted to other mice with the same number of cells. The process was repeated 10 times. The growth characteristics of transplanted medulloblastoma and survival curve of tumor-bearing mice at passage 10 were observed. The pathological characteristics of transplanted tumor were analyzed. Results The transplantable strain of medullo- blastoma with stable in vivo properties was named PUMC-MBT1. The successful rate of tumor transplantation was 100% at passage 10. The subcutaneous mass could be palpated 14 days after injection. The diameters of subcutaneous xenograft could reach about 1.5 cm 29 days after injection. Tumor-bearing mice died 50 days after injection. HE sections demonstrated that the transplanted PUMC-MBT1 belonged to classic medulloblastoma and the positive rate of Ki-67, Syn and NeuN were 80%-90%, 40%-50% and 20%-30% respectively. Conclusions A successful animal model of medulloblastoma is established with easy manipulation, characteristic features of classic medulloblastoma, so it is a potential technology for in vivo research.

Key words: medulloblastoma, cell-line-derived xenograft (CDX), tumor strain