Participants at last week’s Fortune Most Powerful Women Summit were joined by two special guests via satellite: Former Hewlett-Packard CEO Carly Fiorina and Elizabeth Edwards, wife of former Presidential candidate John Edwards. The women were unable to attend the Summit in-person due to ongoing treatment for cancer, but they were eager to show their support for Stand Up To Cancer (SU2C), an initiative backed by the entertainment community to help accelerate groundbreaking cancer research.