Shannen Doherty hopes Princess Kate's cancer diagnosis will be a wakeup call for the public following weeks of conspiracy theories about the British royal's health.

The "Beverly Hills, 90210" star, who was diagnosed with breast cancer in 2015, took to Instagram to react to Princess Kate's announcement on Friday that she is battling cancer. The Princess of Wales, 42, stepped back from the public eye in January following planned abdominal surgery, which sparked many rumors about her health.

On Instagram, Doherty stressed the need for celebrities to have privacy while undergoing health challenges, writing that "being a public figure does not mean the public owns that person."

"We ALL have the right to go thru illness or life privately," she said. "The onslaught of conspiracy theories, ownership and plain morbid curiosity forced this person to explain herself before she had come to terms with it and explained to her children."

Doherty added that she prays this will be a "learning moment for us all to respect privacy of others regardless of being in the public eye." She also praised Princess Kate for her "strength" amid the "endless onslaught you've been under while going thru cancer."

Doherty has been battling cancer since 2015. After going into remission in 2017, it returned in 2019. Last year, she shared that the cancer had spread to her brain.

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"January 12, 2023. On January 5th, my ct scan showed (the cancer metastisized) in my brain," she said at the time. "January 12, the first round of radiation took place. My fear is obvious."

In November, Doherty shared with People that the cancer had spread to her bones, and in January, she said on the "Let's Be Clear" podcast that she was undergoing infusion treatment.

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"After four treatments, we didn't really see a difference and everybody wanted me to switch, and I just was like, 'We're gonna keep going with this and see,'" Doherty said. "After the sixth, seventh treatment we really saw it breaking down the blood-brain barrier. Do I call that a miracle? Yeah. For me, that happens to be a miracle right now. That I sort of rolled the dice and said, 'Let's keep going.'"

Princess Kate shared her cancer diagnosis on March 22 after Kensington Palace previously said she would step back from public duties until after Easter, which is on March 31st. The Princess of Wales said that after her "major abdominal surgery" in January, tests "found cancer had been present."

Olivia Munn, who recently revealed she has been privately battling breast cancer, also expressed support for Princess Kate, commenting on Instagram, "Thank you for showing what it's like to fight with grace and determination for yourself and for your family. Wishing you all the best."

Contributing: Taijuan Moorman and Brian Truitt, USA TODAY