Other celebrities announced Wednesday include Denzel Washington, Renee Zellweger, Kathy Bates and Richard Branson. Kareem Abdul-Jabbar, Lance Armstrong and Elizabeth Edwards were previously announced as participants. Performers will include Green Day's Billie Joe Armstrong, Neil Diamond, The Edge, Herbie Hancock, Lady Antebellum and Leona Lewis.
Queen Latifah, Martina McBride and Stevie Wonder were among those already announced. Clooney, in particular, is a fundraising heavyweight. At Sunday's Emmy Awards, he accepted the Bob Hope Humanitarian Award for efforts on behalf of victims of this year's earthquake in Haiti, the 2004 tsunami in Indonesia and the Sept. 11 attacks.
"Stand Up to Cancer" is aimed at raising money to speed up innovative cancer research, according to movie producer Laura Ziskin ("Spider-Man"), who is a cancer survivor and co-founder of the Stand Up to Cancer group.