Pittsburgh cancer center warns of cell phone risks PITTSBURGH - The head of a prominent cancer research institute issued an unprecedented warning to his faculty and staff Wednesday: Limit cell phone use because of the possible risk of cancer. Long, busy summer lies ahead of McCain and Obama While many people will work on their tans this summer, or on summer reading lists or on not working too hard, two exceptions -- John McCain and Barack Obama -- and their underlings will be working. Obama overtakes Clinton in Democratic superdelegates Barack Obama erased Hillary Rodham Clinton's once-imposing lead among superdelegates Saturday when he added more endorsements from the group of Democrats who will decide the party's nomination for president.