21.   The transformation occurs when it is cut by an enzyme that, ironically, can originate from cancer tumors.

22.   The U.S. Food and Drug Administration has given accelerated approval to a pill that promises to help shrink advanced breast cancer tumors, its Swiss manufacturer said Friday.

23.   They then took what they learned and used an antibody to suppress the interaction between chemokines and breast cancer tumor cells injected into laboratory mice.

24.   In experiments with rats, Thompson found that lignans from flaxseed sharply reduced breast cancer tumors.

25.   The scientists identified a specific carcinogen in cigarettes that appears to cause a gene mutation found in most lung cancer tumors.