U2's The Edge, also known as David Evans, has become the first contemporary artist to play a gig in Rome's iconic 15th century Sistine Chapel.
The rock guitarist, with seven Irish teenagers on stage with him, sang four songs, including a cover of Leonard Cohen's If It Be Your Will and three U2 songs.
The gig was part of the Cellular Horizons conference organised by the Stem for Life Foundation which promotes the use of adult stem cells to cure rare diseases. The Edge's audience consisted of 200 doctors, scientists and donors connected with the foundation.
Evans' own daughter overcame leukaemia in 2006. A year later he joined the board of the Angiogenesis Foundation, which promotes new blood vessell growth. Just weeks ago, his father died of cancer.
"Usually when I mention angiogenesis people's eyes glaze over. But you all understand what I am talking about," he said during the performance.
"When they asked me if I wanted to become the first contemporary artist to play in the Sistine Chapel, I didn't know what to say because usually there's this other guy who sings," he said, according to NBC.
He thanked Pope Francis "for allowing us to use the most beautiful parish hall in the world".
He added: "Being Irish you learn very early that if you want to be asked to come back it's very important to thank the local parish priest for the loan of the hall."
Vice President Joe Biden, whose son Beau recently died of brain cancer, addressed the conference on the vital need for cancer research funding.
