The shocking and heartbreaking loss of Beastie Boys member Adam Yauch (MCA) today left stars speechless ... except, of course, when those speeches are 140 characters or less. Yauch passed away at the age of 47 today, May 4. The rapper was battling cancer in the parotid gland, which is the largest of the salivary glands, as well in a lymph node. The 'Intergalactic' rapper had undergone both surgery and radiation as part of his therapy. Yauch is survived by his wife Dechen and daughter Tenzin Losel, as well as bandmates Adam Horowitz (Ad-Rock) and Mike Diamond (Mike D). Snoop Dogg and Estelle were some of the very first to express their condolences for the Brooklyn-bred MCA, while other MCs like Ludacris and artists like Justin Timberlake were quick to follow suit, rapidly creating the "#RIPMCA" hashtag. Here are some Twitter tributes to the fallen hip-hop icon.