Research may lead to a significant breakthrough in the battle against deadly brain tumors Groundbreaking research from Tel Aviv University may lead to a significant breakthrough in the battle against deadly brain cancer. To begin with, the researchers identified a failure in the brain's immune system, leading to the amplification of cell division and spread of Glioblastoma cancer cells. The failure results partially from the secretion of a protein called P-Selectin (SELP), which, when bound to its receptor on the brain immune cells, alters their function so that instead of inhibiting the spread of cancer cells, they do the opposite, enabling them to proliferate and penetrate brain tissues.