The hip-hop world isn't the only one mourning the loss of Beastie Boys' Adam 'MCA' Yauch. Madonna is also devastated by the death of Yauch, who passed away Friday, May 4, at 47 years old.

The Beastie Boys opened for Madge on the 1985 Virgin Tour, and the Queen of Pop told The Associated Press (via TMZ) that the Beastie Boys were "integral to the musical revolution that was happening to me at the time." The 'MDNA' singer said that Yauch's passing was "sad" and asked God to bless his family.

Yauch passed away at New York Presbyterian Hospital following a nearly three-year cancer battle. He was conscious and surrounded by his loved ones, including his parents, in-laws, wife and daughter. Yauch had been hospitalized since April 14, when the Beastie Boys were inducted into the Rock and Roll Hall of Fame.

Yesterday, Yauch's mother spoke out about the death of her beloved son. “He was a very courageous person,” Frances Yauch said. “He was hopeful to the very end.”