A new study from the University of Copenhagen has demonstrated that selenium found in garlic and broccoli impacts on cancer by slowing down the immune response. The research findings were published in the Journal of Biological Chemistry and detailed the impact on the immune response.
The immune system normally reacts by removing foreign bodies including cancer cells from the body. Some cancer cells have developed an adaptive mechanism blocking the immune system’s ability to recognize them, allowing cancer to develop unabated. Other cancer cells overexpress immunostimulatory molecules in liquid form. Such over-stimulation has a negative impact on the immune system:
“You can say that the stimulating molecules over-activate the immune system and cause it to collapse, and we are, of course, interested in blocking this mechanism. We have now shown that certain selenium compounds, which are naturally found in, e.g., garlic and broccoli, effectively block the special immunostimulatory molecule that plays a serious role for aggressive cancers such as melanoma, prostate cancer and certain types of leukemia,” said Professor Søren Skov, Department of Veterinary Disease Biology, University of Copenhagen.
The focus of this study was on the NGK2D ligands, consisting of eight variants. One variant is able to assume liquid form and causes significant serious problems once the cancer is fully developed. The entire bloodstream is, so to speak, infected, and the molecule is therefore used as a marker of serious illness.
“Molecules are found both on the surface of the cancer cells and dissolved in the blood of the affected person. We are now able to show that selenium compounds appear to have a very beneficial effect when it comes to neutralising the special variant of the NGK2D ligand — both in soluble form and when the molecule is placed on the cell surface,” said Professor Søren Skov.
“The overexpression seen in cancers such as melanoma, prostate cancer and certain types of leukemia significantly impairs the immune system. If we can find ways to slow down the over-stimulation, we are on the right track. The new results are yet another small step towards better cancer drugs with fewer adverse effects,” said Søren Skov.
M. Hagemann-Jensen, F. Uhlenbrock, S. Kehlet, L. Andresen, C. Gabel-Jensen, L. Ellgaard, B. Gammelgaard, S. Skov. The Selenium Metabolite Methylselenol Regulates the Expression of Ligands That Trigger Immune Activation through the Lymphocyte Receptor NKG2D. Journal of Biological Chemistry, 2014; 289 (45): 31576 DOI: 10.1074/jbc.M114.591537