Seems just like old times. The cast of "The Mary Tyler Moore Show" will reunite on the small screen, and they've got none other than Valerie Harper making it to the party -- a sure-to-be-poignant, funny and treasured moment in the wake of her revelation that she has been diagnosed with terminal brain cancer.

Per Deadline, the sitcom confab is set to happen in an upcoming episode of "Hot in Cleveland," where series star Betty White will be joined her old "MTMS" pals Mary Tyler Moore, Cloris Leachman, Georgia Engel (who's already got a regular guest stint on the show), along with Harper.

Valerie Harper: I have terminal brain cancer

This will mark Moore's second appearance on the show and, reportedly, the gals' first reunion since "MTMS" bid adieu in 1977.

In the episode, which is supposedly set to shoot on April 5, White's old cohorts will play her former teammates on a squad called GLOB -- aka The Gorgeous Ladies of Bowling -- who reunite years after a falling-out over inflated egos. (Is everyone feeling an awesome strike, here?)

Earlier this month, Harper announced that she had been diagnosed with leptomeningeal carcinomatosis -- a rare cancer attacking the fluid-filled membrane enveloping the brain -- and that doctors had given her between three and six months to live.

Valerie Harper opens up about terminal brain cancer diagnosis on TODAY

But the actress says she's determined not to let her illness define her remaining days.

"I'm not dying until I do. I promise I won't," she told the TODAY show two weeks ago. "More than hopeful, I have an intention to live each moment fully."

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CBS Photo Archive / Getty Images

Actresses Valerie Harper, left, and Mary Tyler Moore in 1975.

Actress Valerie Harper may have a positive outlook on her diagnosis of terminal brain cancer, but her on-and-off-screen BFF Mary Tyler Moore can't help but feel down.

"I'm absolutely devastated by this news," the "Mary Tyler Moore Show" star, who underwent surgery for a brain tumor in May 2011, told People magazine. "Valerie has given so much joy, laughter and love to the world. I join her fans and send much love and positive thoughts to her and her family during this difficult time."

Harper recalled phoning Moore the day before her news went public.

Valerie Harper: I have terminal brain cancer

"She said, 'What's up?' I said, 'It's incurable cancer.' She said, 'Val, I'm so sorry,'" Harper told the mag, who first broke the news in its latest issue. Before ending their phone call, "Mary said, 'One day at a time,'" says Harper. "That's how we've got to live our lives. That's the best we can do."

Harper explained that numerous tests showed she had leptomeningeal carcinomatosis, a rare disorder in which cancer cells metastasize into the fluid-filled membrane enveloping the brain. Doctors have given her "as little as three months left to live."

"I don't think of dying," she told People. "I think of being here now."

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Slideshow: Valerie Harper

David Livingston / Getty Images Contributor

Launch slideshow

Everett Collection

Happy 75th birthday, Mary Tyler Moore. You might just make it after all.

Mary Tyler Moore turns 75 today, but to millions of Americans, she's still 32, forever driving from her small hometown to Minnesota's Twin Cities on a sunny freeway in 1970. How will she make it on her own? This world is awfully big, and girl, this time she's all alone.

But she had determination, moxie, smarts, charm, and something Lou Grant hated -- spunk.

After all, she'd already captured America's hearts in another beloved show when she played Laura Petrie, New Rochelle's "hostess with the mostess" on "The Dick Van Dyke Show." There's something magical about this scene, in which she dances in her famed capri pants. What, your parents' parties didn't involve conga drums and elaborately choreographed dances in the living room? Ours either, but this show made us wish they did.

Before "Dick Van Dyke," a teenage MTM played the goofy little sprite Happy Hotpoint in dozens of appliance commercials. You might not recognize her here. (Watch the whole ad though if you want a classic 1956 spiel on dishwashers.)

She was a million miles from Laura Petrie or Mary Richards in 1980's "Ordinary People," which earned her an Oscar nomination. Just watch the trailer (and wow, did that movie have a heckuva cast all the way around) and see her brittle, repressed Beth trying to hold things together. Not exactly the mother Laura or Mary would have turned out to be.

But of course, we can't forget "The Mary Tyler Moore Show." I grew up in Minnesota in the 1970s, and although only the opening credits were shot there, it was still a point of pride for residents. If you go to downtown Minneapolis, you can still eat at the very restaurant table (marked with a plaque) in the IDS Crystal Court where Mary and then-husband Grant Tinker are seen dining in the credits.

Everyone knew where the house was that was shown as Mary's, and also knew the real reason why Mary moved to an apartment in later seasons. When the studio came back to film the same giant lakeside home's exterior, its owner hung an "IMPEACH NIXON" banner on the home, forcing them to shoot elsewhere (it was 1973, after all).

I once interviewed one of the Toughskins-clad schoolkids who appear in the credits crossing a street with Mary and a school patrol. He was just walking home from school with friends one day, he said, when a man yelled "Hey! You kids wanna be on TV?" Half the gang scattered, and half stuck around and when ordered, crossed the street while Mary strode along with them, clutching a grocery bag. I sometimes wonder if the half that scattered know exactly what they missed out on.

 There are too many classic "MTM" scenes to share, but Chuckles the Clown gets mentioned more than any other, and for good reason. Watch the bit where Mary scolds Murray for cracking wise -- "A man has DIED!" -- and then see if you can't feel her embarrassment when it turns out she's the one who can't stop laughing. Until the moment she's told to laugh, when of course she bursts into tears.

What's your favorite Mary Tyler Moore character, scene or line? Tell us in the comments or on Facebook.

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