【Animal modeling】-Nude mouse prostate cancer metastasis model

  [Modeling mechanism] Even after transplantation due to immunodeficiency, nude mice undergoing human tumor xenotransplantation will grow well. The morphological and functional characteristics of human tumors transplanted into nude mice are basically the same as those before transplantation. Human prostate cancer should be inoculated into nude mice with LNCaP cells, and allograft between mice should be used to establish a nude mouse xenograft model of human prostate cancer.

  [Modeling method]

  1. BALB/c male nude mice are 3-5 weeks old and weigh 18-23 g. Human prostate cancer LNCaP cell line.

  2. Digest and recover LNCaP cells in the logarithmic growth phase, and take a small amount of cell fluid to make the cell concentration close to 1×1000000000/ml. The nude mouse was anesthetized with ether, and 200 μl of cell solution was sucked with a 1 ml syringe and injected into the armpit of the nude mouse. Observe the implantation site every day to understand the incubation period and growth rate of tumor growth. When the diameter of the tumor becomes about 10mm, the subcutaneous solid tumor is excised and cut in half with a scalpel. One is fixed with formaldehyde for pathological examination, and the other is placed on a plate and incubated with F-12. Wash with liquid. Remove the necrotic tissue in the middle, remove the muscles and blood vessels around the tumor tissue at the same time, select the live cells at the edges, cut into approximately 1 cubic millimeter aliquots, wash 3 times with culture medium, and place them naked under the skin of the mouse forelimbs for allograft Transplantation and passage, transplanted into nude mice and kept sterile, when the transplanted tumor grows to 8-10 mm, I went to experiment.

  3. Model test (1) Growth curve of transplanted tumor: 10 days after cell inoculation and 5 days after transplantation, regularly observe the growth rate of the tumor and measure its length (a) and width (b). Calculate the volume of the tumor. ②Tumor histopathological examination: embed the tumor fixed with 10% formaldehyde solution in cold paraffin, cut the tissue for routine hematoxylin-eosin (H&E) staining and immunohistochemical examination.

  [Characteristics of the model] LNCaP cells were subcutaneously inoculated into the forelimbs of nude mice and passed between the allograft and the tumor mass. The success rate of tumor transplantation in nude mice reached 100%.

  [Model evaluation and application] The advantages of transplanted tumor models are high success rate, short cycle, consistent tumor growth rate, small individual differences, similar host survival time and body response, and simple objective judgment. The disadvantage is that, unlike the primary tumor of the human body, it cannot fully represent the biological characteristics of the primary tumor. It is more suitable for drug efficacy screening and the study of prostate cancer metastasis mechanism.