Julius Erving never shies away from a challenge.

Give credibility to the upstart ABA? Check. Win an NBA MVP? Check. Bring the first NBA title to Philadelphia since Wilt? Check. Make the slam dunk contest a staple of the NBA? Check.

There is, however, one challenge Dr. J has not conquered yet. It may also be the challenge Erving has fought hardest for the longest period of time.

The doctor fights for the cures.

Underneath his dunks, reverse layups and afro hairstyles lies another side of Erving. It was side NBA fans knew little about during Dr. J's playing days. Each time Erving took the court, he did so with disease on his mind.

At age 19, while a freshman at UMass, Erving lost his 16-year-old brother, Marvin, to lupus erythematosus, a systemic autoimmune disease. When he was 34, his older sister, Alexis, passed away of colon cancer at age 37.

Erving won three titles (two ABA, one NBA), four MVP Awards (three ABA, one NBA) and the first recorded slam dunk contest in basketball history. Those moments do not resonate in his mind with the same color and emotion as the sudden deaths of his brother and sister.

"I lost them in the ultimate fashion," Erving said in a phone interview. "When you lose someone who's the closest person in your world, and you do it twice to these untreatable disorders, it's something that becomes a part of you."

Erving played 16 professional seasons in his Hall of Fame career, but the glory was not just for him. While Erving's afro soared through the air and ignited crowds across the nation, he was playing not just for himself, but for his loved ones as well. Dr. J lost his two biggest fans before the end of his career, but they never left his soul on the court.

"Of course I thought of them," he said of his playing days. "My family, they're always with me. I always think of dedicating the next step I take to them."

That's why Erving has worked with the Philadelphia Tri-State Chapter of the Lupus Foundation of America to create the Julius Erving Fund, which supports research and treatment to those affected by Lupus. Erving has raised money for cancer research, cancer treatment and worked with the Special Olympics. He has also been involved with the Hempstead New York Salvation Army since his childhood in Nassau County, N.Y.

It is fitting Erving will be honored Friday at the Harold Pump Foundation's 12th annual gala in Los Angeles. The foundation, under its mission "to raise funds and create awareness for the treatment and cure of cancer,” has given about $4.8 million to charity in its 12-year existence. Past honorees have included Muhammad Ali, Denzel Washington, Jerry West, Hank Aaron, Magic Johnson and Bill Russell. Sandy Koufax and Joe Namath are among Erving's 2012 fellow honorees.

Dana and David Pump, along with their mother, Carole, started the foundation in 2000 to their father, Harold, who died of Lymphoma in 1999. The twin brothers can relate to Erving's experiences losing loved ones to cancer and lupus, a disease that can increase the likelihood of cancer. Dana and David believe Erving is a prime representation of what the foundation stands for.

"I think when he talks that night, he can talk about his life experience," David said in a phone interview, along with Dana. "Cancer's touched everyone in that room in some way, some form."

Erving has attended the event for a few years now, and he introduced Hank Aaron, a 2010 honoree. The Doctor is appreciative of the award, but he does not want his personal accomplishments to overshadow the accomplishments of the Harold Pump Foundation as a whole.

"It's a high honor," Erving said. "We know that the ultimate beneficiary of the evening will be the hospital and the patients who are being treated for cancer. The gathering is just second to none and for a good cause."

That hospital, the Northridge Hospital Medical Center in Los Angeles, has received $4.2 million from the Harold Pump Foundation in the past 12 years.

At this year’s event, the foundation expects to raise $1.5 million.

Other attendees expected Friday include Joe Torre, Tony LaRussa, Jim Brown Pete Rose, Oscar Robertson, Jamie Foxx, Larry King, Jerry Rice, former president of Mexico Vicente Fox and Allen Iverson. According to the Pump brothers, Kareem Abdul-Jabbar and Isiah Thomas are scheduled to present Dr. J's award.

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Erving says a wide variety of famous faces coming together to fight for a cause can have a meaningful impact on others.

"I think all the athletes coming together under one roof, that's more important than the titles we have," he said. "The beneficiary, that's the biggest thing. Everyone there is a giver in some way, shape or form."

The Pump Brothers can only smile in amazement at their foundation's success. A seed that started with a $1 million commitment a dozen years ago has turned into one of the most influential fundraising organizations in Hollywood. With the money raised at Friday's event, the foundation could soon cross the $6 million barrier in terms of money given to charity. For Erving to talk about the importance of Hall of Fame athletes and him at the event, the Pumps have come a long way. "Ron Cey was our biggest celebrity, year one. We thought we hit a home run," David said.

While the Pump twins admit they are still humbled by Erving and his peers, they understand the importance of having such high-profile names at their events. Like Erving, they believe the celebrities and athletes set a powerful example for others.

"The awareness is priceless,” David said. "I think by these stars lending names to the foundation, it gives awareness in the community about what the Harold Pump Foundation is doing. I think it's bigger than the athletes, our star power."

"There's a huge difference between what you raise and what you give," Dana says. "I am so passionate and up front about the amount of money we’ve given away to charity. These guys, are childhood idols, have helped."

For Erving, raising money to fight lupus and cancer is not a chore, but a passion. He plans to continue lending his hand to charity and hopes to spread lupus and cancer awareness.

In terms of donating to Lupus and cancer awareness or volunteering for charity, Erving has a message for those on the fence: "We're all affected by this. Do what you can. And don't think twice about it. Just do it."

Erving is also currently a spokesperson for CORD:USE, a life sciences and services company focused upon providing proven high quality stem cell therapeutics to patients in need.

"I'm presently very, very humbled I’m involved with the company," he says. "We work very diligently to improve the quality of life and in come cases change the lives of those affected."

As the legend goes, Dr. J received his nickname at Roosevelt High School in Roosevelt, N.Y., during the 1960s. He called teammate Leon Saunders the professor, and Saunders, in turn, called Erving the doctor. The nicknames stuck with Erving and Saunders when they played together at UMass, and eventually for Erving, in ABA and NBA.

More than four decades later, it looks like there may have been some foreshadowing in Erving's nickname. When the basketball world needed holes filled, Erving arrived to patch them up. When deadly diseases such as lupus and cancer need a role model to fight for the cures, who better to call upon than the doctor himself?

"He's iconic. He's one of the greatest players of all-time," David said. "We had Michael Jordan, we had Larry Bird, and in his generation, still today, he's The Doctor. I think by The Doctor lending his hand and being there, he'll make a difference."

Sure, 30,026 points, 10,525 rebounds and the cradle dunk left an effect on the NBA. But it may be nothing compared to the lives Erving saves in his fight against cancer and lupus.

Think about that the next time you buy a pair of Converses.

-- To donate to the Harold Pump Foundation's fight against cancer, click here.

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