Two drugs that are commonly used for chemotherapy, acted adversely on the immune system of mice. In particular, the formulations utilized in the process of tumor growth, which can diminish their effectiveness in the treatment of cancer, researchers have found in an article published in the current issue of Nature Medicine.
The researchers, led by Francois Giringelli from the National Institute of Health and Medical Research in Dijon, having studied the effect of these two drugs against cancer, as gemcitabine and fluorouracil, found them extremely dangerous side effect on the culture of a mixture of cancer cells and immune.
The immune system, as the scientists explain, has always been considered to be a kind of ally of chemotherapy drugs. Many doctors consider, in particular, that chemotherapy contributes to the weakening of protection cancerous tumor, allowing subsequently cells "medics" to destroy it.
Giringelli colleagues decided to test this claim, having spent observing the reaction of the immune cells to the appearance of a medium molecular fluorouracil or gemcitabine. Scientists at the time of the experiment followed by which cells die in culture, and what substances were allocated their living comrades.
As it turned out, the anti-cancer drugs do not help the immune system, but on the contrary, prevented her. It turned out that the main positive effect - the death of MDSC-cells that suppress the immune system, accompanied by a number of side effects.
In their decay products contained in the particular molecule interleukin-1 beta (IL1B). This causes the protein to synthesize another substance organism - interleukin-17, which stimulates the growth of cancerous tumor types. This factor has a negative impact on the ability of opposition body cancer.
This effect is presumed to scientists, can be neutralized, if the "off" gene Nlrp3, participating directly in the production of interleukin in the MDSC-cell death. To test this hypothesis, the researchers bred mice with a disabled gene Nlrp3.
Biologists in the experiment were injected into the muscles rodent cancer cells, allowing them to develop into a malignant tumor. The researchers then tried with injections of gemcitabine, fluorouracil cure her. The same procedure took place at the same time the mouse has a normal copy of the gene Nlrp3.
Thus, in the experience of biologists confirmed suspicions - mice with altered gene respond better to chemotherapy than their relatives with a "normal" gene.
Giringelli and his colleagues believe that this fact is quite possible to apply in practice, adding to the drugs for chemotherapy components that inhibit or neutralize interleukin its synthesis. This method will help to strengthen substantially its effectiveness, reducing harm to the body, characteristic of all chemotherapy treatments, as noted in the conclusion of the researchers.