Brussels, 31 Aug 2005
Scientists from the Flanders Interuniversity Institute for Biotechnology (VIB) have unveiled a breakthrough in cancer research. The researchers discovered the function of a mediator, protein Ptprv, involved in suppressing the development of tumours.
Using a mouse model, they have shown that the absence of the mediator makes the mice susceptible to the development of cancer. Through this research, the scientists are contributing to a better understanding of the molecular mechanisms that control tumour development.
The cell cycle is a vital, controlled process in our body. The cells that compose our body are constantly being replaced: old cells die and new ones are produced. In the course of this process, each cell goes through a well-organised series of phases. First, the hereditary material, or DNA, in the cell nucleus is duplicated. Next, the nucleus divides itself in half; and then the entire cell divides, and the daughter cells grow into completely new cells. Because it is crucial that this cell cycle runs perfectly, various control points have been built in to enable the cell to control the stability of the DNA. If the DNA becomes damaged, the cell cycle will come to a stop.
The p53 protein, a nuclear protein, plays an essential role in the regulation of the cell cycle, as it is responsible for stopping it. Normally, this happens at the end of the growth phase. But, if the DNA has been damaged or if other problems arise, p53 can also trigger programmed cell death. Because p53 can halt the further growth of cells, this protein plays an essential role in suppressing the development of tumours and blocking the onset of cancer. When cancer appears, the p53 protein is deactivated - either through an alteration or mutation in the gene itself, or through modified activity of the proteins that regulate p53 or that influence its activity.
Research by the Belgian team has revealed that the protein Ptprv works with p53. Under certain circumstances, p53 directly influences the production of Ptprv. In the case of DNA damage, Ptprv turns out to play a key role in stopping the cell cycle and also contributes to blocking the development of tumours. This important role for Ptprv has been demonstrated using mouse models. After exposure to carcinogens, mice that lack Ptprv develop cancer much more readily than other mice do. The findings of the Ghent researchers show that Ptprv is an essential player in preventing and counteracting cancer.
Although the team has elucidated its role in the development of cancer, the actual function of Ptprv has not yet been discovered. Further research may reveal whether Ptprv can provide new leads for the treatment of cancer. To download the abstract of the EMBO Journal paper, please: click here