The Seattle-based Fred Hutchinson Cancer Research Center has announced an unrestricted $15 million gift, the largest in its history, from Seattle native Robert M. "Bob" Arnold.

In making the gift, Arnold, a retired banking executive and former member of the cancer center's board of trustees, said he was inspired by the example of his late mother, Seattle philanthropist Grace Heffernan Arnold, a longtime advocate of the Pacific Northwest Research Foundation, the first private nonprofit biomedical research organization in the Northwest. In honor of the gift, the center's public health sciences division facility will be named the Robert M. Arnold Building.

"Helping research was so important to my mother," said Arnold in a statement. "Over the years, it's carried great weight for my entire family. I can't think of a better way to give tribute to my mother than by supporting Fred Hutchinson."

"In his leadership role, Bob understands that running one of the most prestigious medical research facilities in the nation, with its world-class scientists and state-of-the-art technology, carries a significant price tag," said Carl Behnke, chair of the Hutchinson's board of trustees. "His magnanimous gift will provide seed money to fuel new research and help millions of patients and families worldwide."