Tinashe and Britney Spears at Axis at Planet Hollywood on Wednesday, Jan. 25, 2017, in Las Vegas. Singer-songwriter and NBC’s “The Voice” coach Gwen Stefani has confirmed that she’ll sing at “The Power of Love” Gala here April 27. The Keep Memory Alive fundraiser for our Cleveland Clinic Lou Ruvo Center for Brain Health is honoring tennis champion and Las Vegas resident Andre Agassi and business mogul Ron Perlman this year.