Research Interests:
Because the period between puberty and first child birth represents a key time during which breast cancer risk is determined, adolescent mammary gland development has been identified as a unique target for chemopreventive strategies.  Epidemiological data demonstrate an inverse relationship between adult Vitamin A intake and breast cancer risk   In support of the epidemiological data, Vitamin A has been shown to be anti-proliferative and pro-differentiative in cell culture models of breast cancer—attributes anticipated to reduce breast cancer risk. These data, however, are contradictory to clinical trials in which Vitamin A treatment has been shown to promote lung cancer in high risk individuals.  We have investigated intake of dietary Vitamin A during adolescence on susceptibility of the adult gland to MNU-induced carcinogenesis using the Sprague-Dawley rat model.  In our studies, rats were administered diets deficient, adequate or mildly supplemented in Vitamin A from 21 to 63 days of age, the window of development that coincides with sexual maturation and mammary gland development.  After the 42-day diet intervention, rats were placed on adequate levels of Vitamin A for the duration of the study, thus limiting the intervention to adolescence. Rats were carcinogen treated at 70 days of age.   In one study the Vitamin A doses were administered by feeding rats whole foods which varied in Vitamin A content.  In another study, Vitamin A doses were administered by supplementing purified diets with retinyl palmitate. In the whole foods study, Vitamin A supplementation correlated to a reduced risk in tumor multiplicity; however, in the purified diet, Vitamin A supplementation correlated with a slight increase in tumorigenesis.  In both studies, Vitamin A supplementation inhibited alveolar development; a progesterone-dependent, glandular structure.  In neither study was Vitamin A found to be anti-proliferative, as in vitro work would have predicted.  As differences in epithelial cell proliferation did not account for the difference in mammary gland structure between Vitamin A deficient, adequate, and supplemental groups, we looked at the effects of Vitamin A on progesterone, a hormone required for alveolar differentiation. Progesterone, as well as estrogen and prolactin levels were unaffected by Vitamin A intake. Progesterone receptor expression was also unchanged in response to Vitamin A dose.  Vitamin A did, however correlate to decreased expression of the progesterone responsive genes WAP, β-casein, CBP/p300 and Stat 5.  These data suggest that Vitamin A supplementation is reducing progesterone responsive gene transcription by altering progesterone receptor activity, either directly or indirectly.  In summary, adolescent mammary gland development is highly modulated by dietary intake of vitamin A, and impacts susceptibility to chemical carcinogens in the adult.

Personal Interests:
While I’m not concocting something in the laboratory, I’m concocting something delicious in the kitchen.  I love creative cooking, a skilled I learned after coming home hungry from the lab and being too tired to go shopping for dinner ingredients.  I also love teaching—I can be found moonlighting as an O. Chem TA or a Gen. Chem instructor.  And, if you’re ever around my desk, you’ll find, intermingled with the many scientific pathways and pictures, a lot of animal pictures.  I have a thing about petitioning for wildlife and ecologic preservation.  You’ll also be able to find a few pictures of my own, fury, little children—they don pointed ears, orange fur, whiskers, and puffy tails.  Although I’ve only been able to teach them one word, “meow,” they are very smart--sometimes I wonder if they might be kneazles. 

Publications:

Tarbutton, E., Peden, A.A., Junutula, J.R., and R. Prekeris.  (2005) Functional Properties of RCP and Rip11 in Rab11 function. Methods in Enzymology.

McDaniel, S.M., C. O'Neill, Metz ,R., Kaeck, M., Sapuntzakis, M., E.Tarbutton, Heimendinger, J, Wolfe P., Thompson, H., and Schedin, P. Adolescent intake of a carotenoid rich whole food diet protects against chemically-induced mammary carcinogenesis in the rat. Submitted, 2006.

Latest Publications in PubMed