TY - JOUR
T1 - α-Tocopherol attenuates the cytotoxic effect of δ-tocotrienol in human colorectal adenocarcinoma cells
AU - Shibata, Akira
AU - Nakagawa, Kiyotaka
AU - Sookwong, Phumon
AU - Tsuduki, Tsuyoshi
AU - Asai, Akira
AU - Miyazawa, Teruo
N1 - Funding Information:
This work was supported by a Grant-in-Aid from the Biooriented Technology Research Advancement Center of the National Agricultural and Biological Research Organization, Japan .
PY - 2010/6/25
Y1 - 2010/6/25
N2 - Recent studies have demonstrated that tocotrienol (T3) is superior to tocopherol (Toc) for cancer chemoprevention. However, there is little information on whether Toc influences the anticancer property of T3. In this study, we investigated the influence of Toc on the cytotoxic effects of δ-T3 in DLD-1 human colorectal adenocarcinoma cells. Toc, especially α-Toc, attenuated δ-T3-induced cytotoxicity and apoptosis in DLD-1 cells, whereas Toc alone did not exhibit any cytotoxic effect. δ-T3-induced cell cycle arrest and proapoptotic gene/protein expression (e.g., p21, p27, and caspases) were abrogated by a-Toc. Furthermore, coadministration of α-Toc decreased δ-T3 uptake into DLD-1 cells in a dose-dependent manner. These results indicate that α-Toc is not only less cytotoxic to cancer cells, but it also reduces the cytotoxicity of δ-T3 by inhibiting its cellular uptake.
AB - Recent studies have demonstrated that tocotrienol (T3) is superior to tocopherol (Toc) for cancer chemoprevention. However, there is little information on whether Toc influences the anticancer property of T3. In this study, we investigated the influence of Toc on the cytotoxic effects of δ-T3 in DLD-1 human colorectal adenocarcinoma cells. Toc, especially α-Toc, attenuated δ-T3-induced cytotoxicity and apoptosis in DLD-1 cells, whereas Toc alone did not exhibit any cytotoxic effect. δ-T3-induced cell cycle arrest and proapoptotic gene/protein expression (e.g., p21, p27, and caspases) were abrogated by a-Toc. Furthermore, coadministration of α-Toc decreased δ-T3 uptake into DLD-1 cells in a dose-dependent manner. These results indicate that α-Toc is not only less cytotoxic to cancer cells, but it also reduces the cytotoxicity of δ-T3 by inhibiting its cellular uptake.
KW - Apoptosis
KW - Cytotoxicity
KW - Tocopherol
KW - Tocotrienol
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UR - http://www.scopus.com/inward/citedby.url?scp=77955482300&partnerID=8YFLogxK
U2 - 10.1016/j.bbrc.2010.05.087
DO - 10.1016/j.bbrc.2010.05.087
M3 - Article
C2 - 20493172
AN - SCOPUS:77955482300
SN - 0006-291X
VL - 397
SP - 214
EP - 219
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 2
ER -
