Clooney, Will Smith join anti-cancer telethon
Other celebrities announced Wednesday include Denzel Washington, Renee Zellweger, Kathy Bates and Richard Branson.
Performers include Green Day's Billie Joe Armstrong, Neil Diamond, The Edge, Herbie Hancock, Lady Antebellum and Leona Lewis.
"Stand Up to Cancer" will air Sept. 10 at 8 p.m. Eastern on ABC, CBS, Fox, NBC and a number of cable channels.
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