动物实验,肿瘤 z-bo 2020-08-21 572

　　The National Cancer Institute (NCI) announced that the NCI-60 cell line, which has been used by researchers around the world for 25 years, will be "retired" at the end of this spring. It will be replaced by donations from cancer patients and cultured in mice. Of new tumor samples.

　　According to the website of "Nature" magazine, the NCI-60 cell line is a cancer cell sample group used for anticancer drug testing. It helps scientists refresh their understanding of cancer. But today, the NCI-60 cell line has been cultured for thousands of generations and has adapted to the plastic petri dish environment completely different from the original environment, and the genetic composition and behavior of the cells have changed.

　　For this reason, NCI decided to switch to the "human-derived tumor tissue xenograft (PDX)" model, which means implanting small tumors from patients into experimental mice to better simulate their native growth environment. The tumors thus cultivated can also be transplanted to other mice. NCI can provide human tumor cells cultured in these mice to researchers, including data on the gene composition and gene expression pattern of each tumor, as well as the treatment history of the donor.

　　NCI’s approach also reflects a broader trend: some institutions have begun to build PDX model libraries. NCI’s initial goal is to have 1,000 PDX models, and the current number has reached about one-third, but it is expected that when the model library is opened, only 75 will be available to users. In addition, EurOPDX, composed of 16 European institutions, is said to have 1,500 PDX models; the Jackson Laboratory in the United States has 450 PDX models; pharmaceutical companies are not far behind. Novartis released a drug screening tool last year using 1,000. PDX model. Compared to previous cell culture methods or the use of genetically modified mice, these models can help scientists better study the genetic complexity of cancer.

　　Regarding whether mice can be used as a "stand-in" to screen the most effective individual treatment plan, Jackson Laboratory CEO Edison Liu said that the process of cultivating PDX is very slow and the donated patients cannot benefit yet, but Novartis’s approach is Researching a large number of PDX models has great application potential.

　　But the disadvantage of PDX is that it is unavoidable to reject human cells cultured in mice. Researchers are currently working to develop a genetically modified mouse model that can mimic the complete human immune system.