Credit: Jason LaVeris/FilmMagic; Jon Kopaloff/FilmMagic

From one famous survivor to another.

Three years ago, Christina Applegate won her battle against breast cancer. And now, the Up All Night star, 39, is lending her support to Giuliana Rancic, who was recently diagnosed with early stage breast cancer herself.

"I'm here for her," Applegate told E! News of Rancic, 37, who revealed that she was diagnosed in August while preparing for a third round of IVF treatment.

 "I know that journey so well, how that feels [to get] that phone call," said Applegate, who was deemed "100 percent clear" of breast cancer in August 2008 after treatment and a radical, preventative double mastectomy. "I get what's she's going through."

Rancic, 37, is set to undergo a lumpectomy and several weeks of radiation and will "survive" thanks to early detection. She and husband Bill vow to resume their attempts to conceive once the ordeal is over.

"I started realizing I could be an example for women to not just be aware of breast cancer, but to act on it," Rancic said of her decision to go public with her news on The Today Show Monday. "To make an appointment, to give themselves an exam. Because truly, Ryan, the bottom line is, the earlier you find it, the better chance you have of survival."