On July 4, American researchers published a report on the website of the journal “Nature” (Nature) that they found that an important reason why drugs for cancer tumors often fail to achieve the expected results is likely to be the presence of healthy cells in the tumor microenvironment to provide the corresponding conditions for cancer cells, so that it can resist drugs and survive. Tumor microenvironment refers to the local infiltration of tumor immune cells, mesenchymal stromal cells and secreted active media and cancer cells together constitute the local internal environment, which includes many healthy cells. Researchers from the Broad Institute and other institutions in the United States said in a report that they observed the response of cancer tumors to drugs and found that some drugs can obviously kill cancer cells cultured separately in a test tube, but the actual treatment is always poor. The researchers said they simulated the tumor microenvironment in test tubes, culturing both cancer cells and healthy cells before using the drugs in question, and the results showed that those drugs that were effective against isolated cancer cells were much less effective in this case, suggesting that the cancer cells would take advantage of healthy cells in the surrounding environment to resist the drugs. The researchers therefore suggest that when treating cancer tumors, it is necessary not only to administer drugs to the tumor tissue itself, but also to pay attention to measures to weaken the link between cancer cells and healthy cells.