MODEL RELEASED. 3-D molecular modelling. Two researchers wearing 3-D (3 dimensional) glasses to view a molecule on a computer screen. The molecule is the protein topoisomerase II, and is involved in untangling DNA. Some anti-cancer drugs work by blocking this protein. The small box on top of the monitor sends the 3-D graphical information to the glasses on an infra-red beam. The molecule can be rotated to view specific sites and areas. This type of modelling allows the researchers to see the active sites of the molecule, and find the optimum configuration for the intended reactions. This is cheaper and easier than actually making the drugs and testing them in the laboratory.