SYDNEY (AFP) - Australian scientists have discovered pineapple molecules can act as powerful anti-cancer agents and said the research could lead to a new class of cancer-fighting drugs. Scientists at the Queensland Institute of Medical Research (QIMR) said their work centred on two molecules from bromelaine, an extract derived from crushed pineapple stems that is used to tenderise meat, clarify beers and tan hides. One of the molecules, CCZ, stimulates the body's immune system to target and kill cancer cells, the other, CCS, blocks a protein called Ras, which is defective in 30 percent of all cancers. QIMR researcher Tracey...