Adam Yauch, a rapper and founder of the pioneering and multimillion-selling hip-hop group the Beastie Boys, died on Friday in Manhattan. He was 47.

His mother, Frances Yauch, confirmed his death. He had been treated for cancer of the salivary gland for the last three years.

With a scratchy voice that grew scratchier through the years, Mr. Yauch rapped as MCA in the Beastie Boys, who were inducted into the Rock and Roll Hall of Fame this year. They offered many listeners in the 1980s their first exposure to hip-hop. They were vanguard white rappers who helped extend the art of sampling and gained the respect of their African-American peers.

While many hip-hop careers are brief, the Beastie Boys appealed not only to the fans they reached in the 1980s but to successive generations, making million-selling albums into the 2000s. They grew up without losing their sense of humor or their ear for a party beat.