An American shipping magnate’s trust will announce on Monday one of the largest philanthropic gifts to support cancer research: more than half a billion dollars to be divided equally among six institutions, including Harvard Medical School and the Massachusetts Institute of Technology. Joan Brugge, chair of the Department of Cell Biology at HMS, and George Demetri, professor of medicine at the Dana-Farber Cancer Institute, will codirect the Ludwig Center at Harvard. Matthew Vander Heiden, instructor in medicine at the Dana-Farber Cancer Institute, is also quoted.