Establishment Of A Highly Metastatic Model Of Colorectal Cancer Through In Vivo Selection And Its Cell Line

In this study, we aimed to establish a highly metastatic model of colon cancer in mice. as to human colorectal cancer cell, we established a human colorectal cancer postoperative metastasis model in nude mice. As to colon cancer cell of mice, we expect to gain highly metastatic model by selection in vivo, which was high, steady, and intuitionistic metastasis, and to establish its cell line. We investigated their biological characteristics so as to provide a useful animal model for the study of metastatic mechanism and the treatment of colorectal cancer.The main results are as follows,1) To establish a human colorectal cancer postoperative metastasis model in nude mice. Tumor cell line HCT-116 of human colorectal adenocarcinoma was inoculated subcutaneously into nude mice to develop an implantation tumor, which was then used to establish the colorectal cancer metastasis model. Histological intact tumor tissue was then harvested and implanted subcutaneously to the 28 nude mice. Four weeks later, 15 of them were randomly selected as experimental group and had tumor resection. The rest were assigned to the control group. The information of mice survival and tumor metastasis rates were collected. Mice in the control group died after 9 weeks with 23%(3/13) of them had lung metastasis. While in the experimental group, the metastasis rates in lung, lymph node, and spleen were 100% (15/15), 100%(15/15) and 33.3%(5/15) respectively at the end of 17 weeks when mice were sacrificed. This model provide valuable data to study of mechanism of colorectal cancer metastasis and treatment of human colon cancer .2) To establish a highly metastatic model of colorectal cancer in mice by selection of metastasis.Histologically intact C26 mice colorectal cancer tissues were subcutaneously implanted into the mice. In order to gain visible metastatic focus, NOD-SCID mice, immunodeficiency mice were first selected and undertaken tumor resection when tumor reached 1.5cm in diameter. Screening was conducted according to the method of subcutaneous implantation→lung metastasis→subcutaneous inoculation→lung metastasis. Then the same steps were duplicated in natural mice.Tumorgenicity,invasion, metastasis and morphological characteristics of the implanted tumors were studied by light microscopy, electron microscopy, tumor marker and flow cytometry. Highly metastatic models of mice colorectal cancer were...