Her rep, Leslie Sloane, tells TMZ ... "It is with a heavy heart that I confirm the passing of actress Shannen Doherty. On Saturday, July 13, she lost her battle with cancer after many years of fighting the disease."

Sloane continued ... "The devoted daughter, sister, aunt and friend was surrounded by her loved ones as well as her dog, Bowie. The family asks for their privacy at this time so they can grieve in peace."

In 2015, Shannen was diagnosed with breast cancer, but her disease went into remission for a period before returning two years later.

At the time, she told "Good Morning America," "It's going to come out in a matter of days or a week that I'm stage 4. So my cancer came back, and that's why I'm here. I don't think I've processed it. It's a bitter pill to swallow in a lot of ways."

Of course, Shannen became a household name for her role as Brenda Walsh in the popular 90s TV show "Beverly Hills, 90210." She left '90210' after 4 years, but made several guest appearances as Brenda in the 2008 reboot of the program.

She also landed a role as Prue Halliwell in "Charmed," but she exited the show after the third season in 2001. Then she went into reality TV, starring in "Breaking Up with Shannen Doherty" and being a contestant on "Dancing with the Stars."

Shannen was 53.