Amid the crowd at former UC Berkeley professor James Allison’s birthday party was a cancer survivor who owed her life to his newly developed treatment — the very same treatment that earned Allison a Nobel Prize in medicine Monday.

Before moving to work at the University of Texas MD Anderson Cancer Center, Allison helped spearhead the research in the campus department of molecular and cell biology’s division of immunology, of which he was the division head and department chair. He also spent 20 years as the director of the UC Berkeley Cancer Research Laboratory.

According to a press release from the MD Anderson Cancer Center, his treatment — which tackles malignant melanomas — focuses on treating the immune system, rather than attacking the tumor. It has since led several other therapies for other types of cancer, including lung and prostate cancer.

“I never dreamed my research would take the direction it has,” Allison said in the press release. “It’s a great, emotional privilege to meet cancer patients who’ve been successfully treated with immune checkpoint blockade. They are living proof of the power of basic science, of following our urge to learn and to understand how things work.”

Allison’s research began with a fascination about T cells and how they are activated and deactivated, David Raulet, a UC Berkeley immunology professor and former colleague of Allison, said. According to the press release, Allison’s key discovery was that T cells could be freed to attack cancer if a specific protein — CTLA-4 — was blocked. This discovery prompted him to develop an antibody that could obstruct it.

These principles guided the creation of Ipilimumab, a drug that was approved by the Food and Drug Administration to treat late-stage melanoma in 2011. The treatment’s results were unprecedented, and follow-up studies showed that 20 percent of recipients lived for at least three years, with some living up to more than 10 years.

“I’m honored and humbled to receive this prestigious recognition,” Allison said in the press release. “A driving motivation for scientists is simply to push the frontiers of knowledge. I didn’t set out to study cancer, but to understand the biology of T cells — these incredible cells travel to our bodies and work to protect us.”

Raulet said the road to Allison’s success was difficult, especially because many members of the medical community were skeptical about using the immune system to cure cancer, and many pharmaceutical companies were not interested in his work. Ultimately, Allison garnered the support of small biotech companies.

After much research, Allison worked on clinical trials, which took years because cancer patients need to be monitored following treatment, according to Raulet.

“It became clear this was going to really work,” Raulet said. “Many of those patients were cured and are still alive.”

He added that thousands of patients have been positively affected by the treatment.

“While immunotherapy has been a miracle cure for many people, it doesn’t yet work with all cancers,” said Russel Vance, a former colleague of Allison and current director of the UC Berkeley Cancer Research Laboratory. “Jim’s success has inspired those of us in the Cancer Research Lab at Berkeley to continue to work very hard to find the next cure.”