Actor Luke Wilson, 'He's Just Not That Into You''s Ginnifer Goodwin, and "Heroes" star Greg Grunberg gathered at one leg of the Amgen Tour of California to bring awareness to a good cause.

In celebration of the Breakaway From Cancer initiative, and in partnership with Stand Up To Cancer (SU2C), the stars turned out to support the racers and draw attention to the battle against cancer. Luke is an ambassador for Amgen's Breakaway from Cancer initiative and SU2C. Plus, Amgen's Stuart Arbuckle tells ET more about the important cause.

"My own mom is a cancer survivor, and I know how much the support and love of her family and friends has meant to her," Ginnifer said to the crowd at the event.

"It's a real honor to be here, and I just want to thank everyone for making a real effort to come out here today for such a great cause," Luke added.

Stage 7 of the Amgen Tour of California included five, five-mile laps near the area around the Rose Bowl in Pasadena, Calif. -- where Levi Leipheimer (USA) of Astana had the overall lead heading into the next leg of the race in San Diego County, where he eventually won his third Tour of California.

For more information on, visit Stand Up To Cancer at www.standup2cancer.org -- or Breakaway From Cancer at www.breakawayfromcancer.com.