填空题 Unit 6 Text C: Complete the summary of the text with NO MORE THAN FIVE WORDS. Provenge was (1) for each patient by (2) his dendritic cells and exposing them to a (3) called prostatic acid phosphatase. Once (4) into the patient, the exposed cells should trigger an(5) on tumor cells. The vaccine's performance is (6) given its nearly 20-year-old technology, compared with many (7) cancer vaccines. Now a second generation of vaccines aiming at provoking a(8) is under development. For cancer-vaccine developers, (9) is crucial. The struggle to create effective cancer vaccines(10) the memories of the long battle to develop antibody-based therapies: people need to (11) to prove it