Tom Brady was back in town Tuesday, if only briefly, to announce that a portion of the proceeds from this summer’s Best Buddies Challenge: Hyannis Port is being earmarked for victims of the Boston Marathon bombings. Brady is again the honorary chairman of the 100-mile charity ride and walk benefiting Best Buddies International, the nonprofit devoted to helping people with intellectual disabilities. During an appearance at the Seaport Hotel, the Pats QB said money raised by the event’s kickoff festivities — the Tom Brady Football Challenge and Guy Fieri Celebrity Chef Tailgate — will help those affected by the bombings. Brady was joined Tuesday by Best Buddies founder Anthony Shriver. The Best Buddies Challenge: Hyannis Port takes place June 1.