Plant research may help understand cancer

Jan 10 2005

The development of cancer is a complex process with a number of different causes. The root problem is loss of control in the cell division process. A fundamental biological process, cell division can be studied in many organisms.

Researchers from the Flanders Interuniversity Institute for Biotechnology (VIB) connected with Ghent University are studying cell division in plants and thereby uncovering general principles. They are now revealing the importance of the DEL1 protein in the control of cell division in the Arabidopsis plant. The scientists suspect that the human variant of this protein, E2F7, performs the same essential function in human cells. Their research is bringing to light a potentially new class of genes that can suppress the growth of tumors.

Our body is constructed of cells that contain the hereditary material (DNA) distributed among chromosomes - 46 in human cells. Under normal circumstances, our body's cells divide continuously in a very controlled manner: every cell division is preceded by a doubling of the DNA, so that, after division, two cells are formed, each containing 46 chromosomes. But sometimes this process goes wrong, giving rise to cells with an incorrect number of chromosomes. Such an occurrence can undermine the precise control system governing cell division, so that the cell begins to divide without restraint, turning into a cancer cell.

In a small plant like Arabidopsis (or the mouse ear cress), processes such as DNA doubling and cell division are also subject to a complex control system. The VIB research group, under the direction of Lieven De Veylder and Dirk Inzé, is studying cell division in Arabidopsis during the plant's development and, in particular, the function of the DEL1 protein in the cell division process. For this study, they modified plants genetically so that they no longer produced DEL1. The researchers saw that the cells of these modified plants contained noticeably more DNA than the cells of normal Arabidopsis plants. By shutting down DEL1, a doubling of the cell's DNA is no longer automatically followed by cell division. Their research demonstrates the importance of DEL1 in the control mechanism of DNA doubling and cell division.

De Veylder and Inzé suspect that the E2F7 protein - the human counterpart to DEL1 - performs a function in human cells analogous to that of DEL1 in Arabidopsis. According to these scientists, an error in E2F7 could lead to cells containing too many chromosomes, and thus to cancer cells. They want to develop this line of reasoning further with a partner in cancer research in order to better understand the factors that underlie cancer.

http://www.vib.be/