title: Inhibitory Effect of a γ-Tocopherol-Rich Mixture of Tocopherols on the Formation and Growth of LNCaP Prostate Tumors in Immunodeficient Mice.
abstract: In the present study, we determined the effects of a γ-tocopherol-rich mixture of tocopherols (γ-TmT) on the growth and apoptosis of cultured human prostate cancer LNCaP cells. We also determined the effects of dietary γ-TmT on the formation and growth of LNCaP tumors in immunodeficient mice. In the in vitro study, we found that the activity of γ-TmT was stronger than α-tocopherol for inhibiting the growth and stimulating apoptosis in LNCaP cells. In the animal study, treatment of severe combined immunodeficient (SCID) mice with dietary γ-TmT inhibited the formation and growth of LNCaP xenograft tumors in a dose-dependent manner. Mechanistic studies showed that g-TmT administration inhibited proliferation as reflected by decreased mitosis and stimulated apoptosis as reflected by increased caspase-3 (active form) expression in LNCaP tumors. In addition, dietary administration of g-TmT increased the levels of a-, γ- and δ- tocopherol in plasma, and increased levels of γ- and δ- tocopherol were also observed in the prostate and in tumors. The present study demonstrated that g-TmT had strong anticancer activity both in vitro and in vivo. Additional studies are needed to determine the potential preventive effect of g-TmT for prostate cancer in humans.
authors.affiliation: Susan Lehman Cullman Laboratory for Cancer Research, Department of Chemical Biology, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 164 Frelinghuysen Road, Piscataway, NJ 08854, USA. xizheng@rci.rutgers.edu.
authors.forename: Xi
authors.initials: X
authors.lastname: Zheng
authors.forename: Xiao-Xing
authors.initials: XX
authors.lastname: Cui
authors.forename: Tin Oo
authors.initials: TO
authors.lastname: Khor
authors.forename: Ying
authors.initials: Y
authors.lastname: Huang
authors.forename: Robert S
authors.initials: RS
authors.lastname: Dipaola
authors.forename: Susan
authors.initials: S
authors.lastname: Goodin
authors.forename: Mao-Jung
authors.initials: MJ
authors.lastname: Lee
authors.forename: Chung S
authors.initials: CS
authors.lastname: Yang
authors.forename: Ah-Ng
authors.initials: AN
authors.lastname: Kong
authors.forename: Allan H
authors.initials: AH
authors.lastname: Conney