Lung metastasis of human choriocarcinoma in mice: establishment of experimental metastatic model and its biological characteristics / 中华妇产科杂志

ABSTRACT

Objective To establish a satisfactory lung metastasis model of human choriocarcinoma using severe combined immunedeficient(SCID)mice and explore the appropriate cell concentration for the model.Methods Forty SCID mice aged between 5-6 weeks were randomly difided into four groups.1×107 cells/ml ×0.1 ml.5×106 cells/ml×0.2 ml and 1×106 cells/ml×0.1 ml of human choriocarcinoma cells JEG-3 were respectively injected in SCID mice of experimental groups by lateral tail vein,the remain group was assigned to the control group.The status and weisht of mice were observed every three days.When these mice were being dying.the size and the number of the lesions of lung metastasis in every mouse were inspected with Micro CT.After Micro CT inspection,the SCID mice were executed dissected to note whether there were tumors on all organ surfaces witll naked eyes.then made pathological sections from the metastaticfoci of fresh lung tissues,and cultured primarily cells and purified cells and passaged cells isolated from the same metastastic foci.The pathological sections were observed under the microscope.The special antigen human chorionic gonadotropin-beta subunit(β-hCG)of the choriocareinoma cells was immunohistochemically detected in the pathological sections and the cells out of cultured primarily cells.The chromosomes of the cells out of cultured primarily cells were analysed.Results Of the group inoeutated 1×107 cells/ml×0.1 ml.all mice died when inoculating.In the group of 5×106 cells/ml×0.2 ml,when inoculating, 3 mice died; the remain 7 mice were being dying on ( 18. 0 ±2. 0) days after injection. 5 of them, there were 1 - 3 lesions of lung metastasis after Micro CT inspection in each mice, and the diameter of the tumors lesions reached 1.5 - 3.5 ram, which was choriocarcinoma confirmed by pathological sections.The special antigen β-hCG was detected by immunohistoehemical method in the pathological sections of pulmonary tissue with tumor and in the cells, which were purified and passaged from being cultured primarily cells isolated from metastastic foci of fresh lung tissues from the SCID mice. The chromosome numbers of these cells out of cultured primarily ceils were variety from 19 to 128, and medal numbers were variety from 70 to 79. Conclusions We successfully established the lung metastatic model of human choriocarcinoma in SCID mice by injecting JEG-3 cells into lateral tail vein, of which 5 × 106 cells/ml × 0. 2 ml is the suitable concentration and volume for the model.