During one of Zach Sobiech’s hospital stays, he shared a room with a 9-year-old boy. Zach, who was 14 at the time, had been undergoing treatment for osteosarcoma, a rare bone cancer. His roommate had recently lost his leg to the same disease. Laura Sobiech knew the young boy’s struggles deeply troubled her son.

“He said, ‘Mom, if I had to die so that little boy could have his childhood back, I would do it,’ ” Laura recalled. “And he meant it. He wanted his suffering and his death to be for something.”

It already is.

Though he died in 2013 at the age of 18, the Lakeland teen left behind a legacy. Zach recorded “Clouds,” a farewell song for his family and friends. When it became a viral sensation, he designated proceeds from downloads of the song to osteosarcoma research at the University of Minnesota, where he was a patient.

The Zach Sobiech Osteosarcoma Fund crossed the million-dollar threshold last fall. Since its inception, the fund has increased the U’s resources for research on osteosarcoma tenfold and fueled significant breakthroughs in understanding and potentially treating the disease ­— led by Zach’s oncologist.

A promising new drug will undergo clinical trials later this year and U researchers hope they’ll soon be able to design more effective, customized therapies that minimize the punishing side effects of current treatments.

“It is very healing to see that Zach didn’t die in vain, that this legacy of his will affect other kids in the future,” said Zach’s mom. “That’s what he wanted.”

With recent news of a movie deal that could catapult Zach’s fame even further, scientists at the U stand to make even greater strides. Already, the groundbreaking work has positioned the U at the forefront of osteosarcoma research in the United States.

“We are one of the major centers,” said Zach’s oncologist Dr. Brenda Weigel, division director of pediatric hematology/oncology at the medical school. “That was not true prior to the Sobiech money.”

When the U received the first gift from Zach’s fund, Weigel rallied colleagues to examine the disease across disciplines. It was the start of what she calls the osteosarcoma dream team.

Her colleagues in pediatric oncology, epidemiology, surgery and veterinary medicine began comparing their research on osteosarcoma in mice, dogs, and humans, and found similarities that will help identify the genes that are critical to children with the disease.

“We were working in silos, independently,” said Subbaya Subramanian, who analyzes human tumors to develop predictors of their rapid growth. “Now, it’s a collaboration.”

Coming together

Because osteosarcoma is a rare disease, research has long been underfunded, making progress slow, said Weigel. “We’ve made huge advances in some childhood cancers, but with osteosarcoma, we are quite a bit behind.”

Though it’s the most common bone cancer in children, there are only about 600 diagnoses each year in the United States. It often starts as painful swelling, maybe a fracture, in legs or arms. Two-thirds of patients survive it, but not before a grueling treatment that involves 10 months of chemotherapy and surgery.

“Treatment for osteosarcoma hasn’t changed significantly in many decades, so patients need something new,” said David Largaespada, a pediatric hematology/oncology researcher.

His lab was the first to identify the genes that cause osteosarcoma to develop and spread. And, with the funds from Zach, he and fellow researcher Branden Moriarity are developing therapies that activate the immune system to target those genes.

“This collaboration has really accelerated and refined the approach,” said Jaime Modiano, who studies dogs with the disease to find potential treatments for humans. About half of his bone cancer budget came from the Sobiechs. “We were working on this before, but this opportunity filled the gas tank.”

It’s clear that in the age of crowdfunding, Zach’s story struck a nerve.

“What we are seeing in philanthropy is a lot of people trying to make a personal difference by telling stories in compelling ways,” said Sarah Youngerman, University of Minnesota Foundation spokeswoman. “Crowdfunding expands the tentacles in a way you can’t anticipate, and Zach’s story is an extreme example of that.”

In a relatively short time, the fund has been wildly successful in bringing in donations from individuals inspired by Zach.

“It’s pretty rare that we can raise that amount of money just for one type of cancer,” said HaiVy Thompson, spokeswoman for Children’s Cancer Research Fund, which houses Zach’s fund.

Zach recorded “Clouds,” the uplifting folk-pop tune in 2012, with only months left to live. The song quickly rose to the top of the iTunes singles chart, inspired celebrities to sing along in a video and still brings together thousands of people for yearly renditions at the Mall of America. Sales of the song, at 99 cents each, have brought in about a quarter of the overall funds.

“It’s just a dollar, and look what we’ve been able to accomplish,” Laura Sobiech said.

Weigel treasures a signed copy of Zach’s album. When he gave it to her, he told her he hoped it would lead to a cure.

“What’s really awe-inspiring is the vision of a young man who had the gift of music, and what he’s given back,” she said.

“A lot of people ask me, ‘How can you be a pediatric oncologist, how can you treat kids with cancer?’ Zach’s a reason why.”