ImClone Systems Inc. (IMCL), Novartis AG (NVS), Eli Lilly & Co. (LLY) and Genentech Inc. (DNA) are among the drug companies set to showcase their efforts in the battle against cancer at a large medical meeting beginning Friday.The American Society of Clinical Oncology is holding its five-day annual meeting in Chicago, where more than 25,000 cancer doctors are expected to hear the latest in cancer research. As usual, some of the most eagerly awaited data are for drugs that treat the top killers – cancers of the lung, breast and colon.