During the last 10 years, the role of specific nutrients in cancer
prevention and cancer treatment has been the subject of intense basic,
preclinical, and clinical research. At present, the major focus of
nutri- tional oncology is on the mechanisms of carcinogenesis and their
modification by nutrients and on cancer prevention studies in animals
and humans. Some human epidemiological studies have confirmed the
hypothesis, developed on animals, that there is an inverse relation-
ship between the intake and/or level of !3-carotene, vitamin A vita- min
E, or vitamin C and the risk of cancer, whereas others have shown no
such relationship. This is not unexpected, since the protective effect
of individual nutrients may be too small to be detected by
epidemiological methodologies in which a single vitamin or mineral is
considered as one variable. Conclusive evidence regarding the role of
nutrients in human cancer prevention will come from a well- designed
human intervention study using one or more nutrients in a population
that has a high risk of developing cancer. The involvement of specific
nutrients in the regulation of protooncogene expression has just begun.
Also, some of the results of human intervention trials are beginning to
yield interesting results. A large number of interna- tional scientists
from various disciplines, including cell biology, mo- lecular biology,
nutritional oncology, epidemiology, and public health, reviewed and
discussed their most recent findings. The following topics were
emphasized: 1. Mechanisms of carcinogenesis; 2.
