DALLAS — As her sister was dying from breast cancer, Nancy G. Brinker made a promise to her: She would do everything she could to wipe out the disease.

Brinker fulfilled that solemn commitment by founding a breast cancer charity in 1982 that grew into the world’s largest — a national fundraising powerhouse that has invested more than $740 million in research and $1.3 billion in services such as screening and education over the last three decades.

Now Brinker, the public face of Susan G. Komen for the Cure, is stepping down as CEO, about six months after the organization’s hotly debated decision to stop giving grants to Planned Parenthood for breast screenings. The move to withdraw the funding was quickly reversed after an onslaught of criticism but ended up stirring anger on both sides of the abortion debate.

Brinker, 65, will move to a new role focusing on fundraising and strategic planning once a new senior executive has been found.

“She’s wanting now to kind of get away from the day-to-day operation as CEO,” said Komen spokeswoman Andrea Rader. She said Brinker will concentrate on “growing the global work, working on the strategy and of course raising the funds,” and she will still have “a major role in the organization.”

On Wednesday, the group also announced that Komen President Liz Thompson will step down next month, and two board members are leaving as well.

They are just the latest departures. After the Planned Parenthood episode, at least a half-dozen other high-ranking executives resigned, and organizers of many Race for the Cure events — the group’s signature fundraiser — have seen participation decline.

Rader said neither Thompson nor Brinker was available to answer questions today. But she insisted their moves were not the result of the Planned Parenthood decision, saying that Brinker, who has served as CEO since 2009, wanted a different focus.

Thompson, she said, had been thinking of making a change for a while but had agreed to stay on until the controversy died down.

Among those who publicly opposed cutting off Planned Parenthood were some Komen affiliates, including the one for Oregon and southwest Washington, which saw its chief executive resign in the aftermath. The group issued a statement saying it views this week’s leadership changes as “part of the process of moving past the distraction of earlier this year.”

Since February, “supporters have expressed disappointment but also tremendous resolve and a renewed determination,” said Devon Downeysmith, an assistant manager for the affiliate. “The silver lining is that we’ve really been able to reinforce what our mission is, how we save lives and how we provide critical care.”

Downeysmith said the organization was grateful for all that Brinker had done and “how she’s turned the promise to her sister into a global movement.”

Komen had said it had adopted criteria excluding Planned Parenthood from future breast-screening grants because Planned Parenthood was the subject of an investigation launched by a Florida congressman at the urging of anti-abortion groups.

After the decision was made public, much of the anger focused on Komen policy chief Karen Handel, who had opposed abortion as a Republican candidate for Georgia governor. When Komen restored the funding, Handel resigned and said she stood by the decision to pull funding.

In a statement accepting Handel’s resignation, Brinker said the organization had “made mistakes in how we have handled recent decisions and take full accountability for what has resulted.”

Handel said the discussion had started before she arrived there last year because the charity was concerned that some Roman Catholic dioceses had discouraged believers from giving to Komen because it supported Planned Parenthood.

The Komen organization started as a small gathering in Brinker’s living room. Brinker herself was diagnosed with breast cancer in 1984 and helped change breast cancer from a taboo subject to a public cause that drew women into the streets to raise money, many of them dressed in the group’s signature pink.

Brinker and her sister grew up in Peoria, Ill. By the late 1970s, Brinker was living in Dallas, part of the executive training program at luxury retailer Neiman Marcus. Komen, who was three years older, was raising her family in Peoria, working as a part-time model.

After her sister’s death in 1980, Brinker knew she had work to do.

“It wasn’t going to be enough to raise money from some very wealthy people. We needed to change the culture,” Brinker told The Associated Press in a 2007 interview. “We needed to approach this as an eradication of an entire disease.”

In 1981, she married Dallas businessman Norman Brinker, who built a worldwide casual dining empire that included Chili’s restaurants. Although they divorced in 2000, Nancy Brinker said he remained supportive of her efforts with Komen for the Cure and was a lifetime member of the board. He died in 2009.

Brinker served as U.S. ambassador to Hungary from 2001 to 2003 and then as U.S. chief of protocol from 2007 to 2009, overseeing protocol matters for visiting heads of state and presidential travel abroad.

While Brinker was in those posts, she was “always with us but not in an official capacity,” and in the years before that “she did everything,” Rader said.

Rader acknowledged that the controversy had caused some people to donate their money elsewhere. But she said supporters who were upset are returning.

As the Planned Parenthood issue recedes into the past, many people “remember that Komen helped their mother. Or they remember the research, or they hear the story of somebody in the community who couldn’t afford her surgery and we helped them, and they’re more than willing to support it,” she said.

Rader also noted that the organization has made several important changes, including creating an affiliate leadership council and adding a second affiliate spot on the board after Brinker’s son, Eric Brinker, left the board this spring at the end of his term.

Ann Greenhill, executive director of Komen’s greater Fort Worth affiliate said that she trusts the decisions from headquarter and feels like “we’ve moved forward.”

“They are so thoughtful in the changes that they are making, especially after the controversy,” said Greenhill, who added that while the changes at the top may “appease some people, in my heart I know that’s not the reason they did this.”

She said Brinker is especially suited for her new role: “In the early days, people talk about when she was on the phone and she would not take `no’ from people for an answer when they were not going to support Komen.”

“She would not hang up the phone. Boy, she has the passion.”

Associated Press Writer Linda Stewart Ball contributed to this report.