WASHINGTON - A White House aide who joked about U.S. Senator John McCain's battle with brain cancer no longer works in the Trump administration, a source with knowledge of the matter said on Tuesday.During an internal meeting last month, Kelly Sadler, who worked as a White House communications aide, dismissed McCain's objection to President Donald Trump's pick to be CIA director by saying it "doesn't matter, he's dying anyway," a source familiar with the meeting told Reuters.The White House refused to confirm or deny whether Sadler made the remarks.Sadler's departure was first reported by CNN.McCain, 81, was diagnosed with an aggressive form of brain cancer last year. He has been receiving treatment in his home state of Arizona and has been absent from the Senate for months.McCain, who was tortured as a prisoner of war in Vietnam, had released a statement after CIA nominee Gina Haspel's Senate confirmation hearing, denouncing her for refusing to condemn torture. He recommended that his fellow senators vote against her, but the Senate confirmed Haspel 54 to 45.McCain has been a frequent critic of Trump. In 2015, Trump denigrated the former Navy flier's military service, telling a gathering of religious conservatives, "He's not a war hero. He was a war hero because he was captured. I like people who weren’t captured."