Adrian
A. Franke, Ph.D. Professor
(Specialist), Cancer Research Center of Hawaii;
Graduate Faculty, Department of Food Science and Human Nutrition,
College of Tropical Agriculture and Human Resources
Ph.D.
(Pharmacy - Natural Products Chemistry), University of Freiburg, Germany
Intake
of plant foods has been implicated in the risk reduction
of chronic diseases including cancer. The identification
of the phytochemicals responsible for this effect is therefore
of vital interest. The research in my laboratory centers
on the development of biomarkers reflecting exposure to
vegetarian foods and on the pharmacokinetics of chemopreventive
micronutrients. A central role in this respect plays the
accurate determination of food phytochemicals from body
fluids and tissues. Agents from plant foods that are of
particular interest in our projects include lipid-phase
micronutrients (carotenoids, vitamins A and E), flavonoids,
isoflavonoids, lignans, and other phenolic agents. Studies
in my laboratory showed that the most abundant dietary
isoflavonoids, such as daidzein, glycitein, and genistein,
occur predominantly in soy foods. Considering the evidence
that populations with high soy intake experience lower
breast, prostate, lung and other cancers isoflavonoids
may play an important role in this context. In fact, we
found that urinary isoflavone excretion rates are inversely
correlated with breast cancer risk in a Chinese population
from Shanghai. Currently, methods using LC/MS techniques
with electrospray ionization are being established for
the simultaneous measurement of mammalian lignans, flavonoids,
isoflavonoids, and their metabolites from human body fluids.
These techniques are currently applied in dietary intervention
as well as in large-scale prospective epidemiologic studies.
Feeding
experiments with animals including non-human primates
are performed to explore the pharmacokinetics and tissue
disposition of (iso)flavonoids. Experimental studies
are
also directed toward testing the potency of flavonoid
and other phenolic agents in inhibiting carcinogenesis
caused
by human food carcinogens using cell systems and also
a rat model. Support for these studies has been obtained
from private sponsors, local agencies, ACS Institutional
Grants and Center discretionary funds.
Selected
Publications
Franke,
A.A., Custer, L., Hundahl S.; Determinants for urinary
and plasma isoflavones in humans after soy intake. Nutr.
Cancer 50 (2) in press (2004).
Blair,
R.M., Appt, S.E., Franke, A.A., Clarkson, T.B.; Treatment with
antibiotics reduces plasma equol concentraton in cynomolgus
monkeys (Macaca gascicularis). J. Nutr. 133, 2262-7 (2003).
Franke,
A.A., Custer, L.J., Arakaki, C., Murphy, S.P.; Vitamin C and
flavonoid levels of fruits and vegetables consumed in Hawaii.
J. Food Comp. Anal. 17(1), 1-35 (2004).
Franke,
A.A, Custer, L.J., Wilkens L.R., Le Marchand, L., Nomura, A.Y.,
Goodman, M.T., Kolonel, L.N.; LC/PDA/MS analysis of dietary
phytoestrogens from human urine and blood. J. Chromatogr. B
777, 45-59 (2002).
Franke,
A.A., Custer, L. J., Cooney, R. V, Tanaka, Y., Xu, M., Dashwoood,
R.D.; Inhibition of colonic aberrant crypt formation by the
dietary flavonoids (+)-catechin and hesperidin. Adv. Exp. Med.
Biol. 505, 123-133 (2002).
Dai,
Q., Franke, A.A., Jin, F., Shu, X.-O., Hebert, J.R., Custer,
L.J., Cheng, J., Gao, Y.-T., Zheng, W.; Urinary excretion of
phytoestrogens and risk of breast cancer among Chinese women
in Shanghai. Cancer Epidemiol. Biomark. Prev. 11, 815-23 (2002).
