Adam Yauch, better known to fans as "MCA" of the seminal hip-hop trio the Beastie Boys, has died after a long-standing battle with cancer. He was 47-years-old.

The Brooklyn-born rapper was diagnosed in July 2009 with cancer in his salivary gland and had been undergoing treatment ever since then., Russell Simmons' website, first reported his death.

Yauch co-founded the Beastie Boys in 1979 as a hardcore punk band. In 1986, they released 'Licensed to Ill' and exploded on the scene as a full-fledged hip-hop group. From there, they released a series of influential albums, including 'Paul's Boutique,' 'Check Your Head' and 'Ill Communication,' further shaping the genre.

In addition, Yauch was a staunch supporter of the Free Tibet movement and organized the Tibetan Freedom Concerts in the late 1990s.

Yauch was reportedly too ill to attend the Beastie Boys' induction into the Rock and Roll Hall of Fame in April and his treatments delayed the release of the band's most recent album 'Hot Sauce Committee, Pt. 2.' He is survived by his wife, Dechen Wengdu, and their daughter, Losel.

Update: MCA's publicist just released a statement confirming the death, writing, "It is with great sadness that we confirm that musician, rapper, activist and director Adam 'MCA' Yauch ... passed away in his native New York City this morning after a near-three-year battle with cancer. He was 47 years old."

Update: The Beastie Boys website has an official obit.