CHICAGO (CBS) — An abused German Shepherd who captured the hearts of tens of thousands of people was being remembered Thursday for his contributions to humans, after succumbing to cancer earlier this week.

Mr. Brown was on the verge of being euthanized by Chicago Animal Care & Control before volunteers at Hopeful Tails Animal Rescue in Aurora took him in over the summer.

“He had a great smile. He was a very personable and charming dog,” said volunteer Chris Ulreich, who fostered Mr. Brown.

It turned out Mr. Brown had cancer, and he had his front left leg amputated. Thousands followed his story on Facebook, including people suffering cancer.

“A lot of what his page was about was living life to the fullest, enjoying the small pleasures every day. A lot of his posts, and bucket lists, and silly smiles, and different things we would post were just about him enjoying everyday things,” she said.

Ulreich said Mr. Brown’s followers found strength in a dog who had a rough life, and a good support network.

“There was a ton of love and support for him on social media,” she said.

Mr. Brown also took part in a clinical study at Yale University.

“We actually made two trips out to Connecticut to get a canine cancer vaccine,” she said.

The dog died on Monday. Urleich said there are no regrets about the time, money, and effort spent treating Mr. Brown.