The ultimate goal is to develop a tumor to kill cancer cells and prevent their recurrence and to treatment of healthy cells intact. Recently, researchers began to try to develop for "cancer stem cells" to prevent relapse of drug, which survive after the traditional chemotherapy, may generate a new tumor.
A new cancer drug screening use Drosophila found that half of the stem cell targeting tumor recurrence chemotherapy drugs may produce side effects, including some of the FDA-approved drugs.
Experiments showed that some chemotherapy drugs will not only kill cancer stem cells in Drosophila, but can also cause excessive growth of normal stem cells. Because humans and Drosophila certain key biological mechanism similar, so this finding may explain why sometimes after cure of human tumors will grow back. It can also help us to select or develop safer chemotherapy drugs.
"We found that a group of chemotherapy drugs damage the normal stem cells in vivo microenvironment, which leads to excessive proliferation of stem cell responses." First author Michel Marc Stein says, she was originally a postdoctoral fellow at Harvard Medical School, is now Massachusetts Assistant Professor of Amherst College. "This side effect may contribute to tumor growth, but in fact the intention of these drugs are used to inhibit tumor growth."
"Stem cells are very sensitive to the environment, however, a lot of testing drugs targeting cancer stem cells in vitro or laboratory are carried out." Principal investigator professor of developmental biology at Harvard Medical School, the study Norbert. Swiss glass door, added: "Our findings underscore the importance of the study of these drugs in the body, this reflects the real situation in the human body environment." He said: "Drosophila may be a powerful drug screening done system, because it does not oversimplify the biological process. "
Unexpected discovery
Glass doors Swiss research team has created opportunities for an occasional fruit fly models. When the researchers found a cause Drosophila intestinal tumor growth when they investigated the phenomenon of different cellular signal transduction pathways. They realize that they can take advantage of these flies to test compounds inhibit tumor.
Marc Stein developed a simple screening method, which can quickly test hundreds or even thousands of known compounds and by confirming the 14 chemotherapy drugs in the human body also destroy tumors flies to verify the model .
She then normal flies the same 14 kinds of test drugs, with little or no effect on the expected results. Instead, she found door in the narrative called "accidental discovery":. "Incredible proliferation of stem cells," certain drugs caused a
The team believes that these drugs destroy the Drosophila gut a biological process that can be associated with cancer in humans associated with inflammation.
Po Rui doors and Max is determined based on their findings stem cells targeted chemotherapy drug classification: those inhibiting tumor without affecting normal stem cells as a class, and those who inhibit tumor also stimulate overgrowth of normal stem cells for another class. They proposed that the second type of drug may be combined with anti-inflammatory drugs to attempt to counteract the side effects, but a better option is to use a first type of drugs, the side effects can be completely avoided.
Next, the research team tested a collection of 6,100 kinds of drug candidates, and identified 10 flies can destroy tumors without the side effects of drugs.