(AP) - Adam Yauch, the gravelly voiced Beastie Boys rapper and the most conscientious member of the seminal hip-hop group, has died. He was 47.

Yauch's representatives confirmed that the rapper died Friday morning in New York after a nearly three-year battle with cancer.

Also known as MCA, Yauch was diagnosed with a cancerous salivary gland in 2009. At the time, Yauch expressed hope it was "very treatable," but his illness caused the group to cancel shows and delayed the release of their 2011 album, "Hot Sauce Committee, Pt. 2."

He hadn't performed in public since 2009 and was absent when the Beastie Boys were inducted into the Rock and Roll Hall of Fame last month.

"Adam Yauch was a pioneer who broke ground with his music and introduced hip-hop to a wider audience," said Terry Stewart, president of the Rock and Roll Hall of Fame.

The Brooklyn-born Yauch created the Beastie Boys with high school friend Michael "Mike D" Diamond. Originally conceived as a hardcore punk group, it became a hip-hop trio soon after Adam "Ad-Rock" Horovitz joined. They released their chart-topping debut "Licensed to Ill" in 1986, a raucous album led by the anthem "(You Gotta) Fight for Your Right (To Party!)".

Russell Simmons, whose Def Jam label released "Licensed to Ill," said on his website: "Adam was incredibly sweet and the most sensitive artist, who I loved dearly. I was always inspired by his work."

In the seven studio albums that followed, the Beastie Boys expanded considerably and grew more musically ambitious. Their follow-up, 1989's "Paul's Boutique," ended any suggestion that the group was a one-hit wonder. Extensive in its sampling and sonically layered, the album was ranked the 156th greatest album ever by Rolling Stone magazine in 2003.

The Beastie Boys would later take up their own instruments - a rarity in hip-hop - on the album "Check Your Head" and subsequent releases.

The trio of white Jewish kids established themselves as one of the most respected groups in hip-hop at a time when white rappers were few.

Introducing the group at the Rock Hall, Public Enemy rapper Chuck D said the Beastie Boys "broke the mold."

"The Beastie Boys are indeed three bad brothers who made history," Chuck D said. "They brought a whole new look to rap and hip-hop. They proved that rap could come from any street - not just a few."

Yauch also went under the pseudonym Nathanial Hornblower when working as a filmmaker. He directed numerous videos for the group, as well as the 2006 concert film "Awesome: I F----- Shot That!" He also co-founded the film distribution company Osciolloscope Laboratories, named after his New York studio.

Yauch is survived by his wife, Dechen Wangdu, and his daughter, Tenzin Losel Yauch.