Palm Tocotrienol Complex Inhibits Prostate Carcinogenesis
The researchers selected TRAMP mice model because it bears close resemblance to the various stages of human prostate cancer such as progression of the disease from early prostatic intraepithelial neoplasia lesions to a more aggressive metastatic adenocarcinoma.
Jul 30 2010 --- Published in the August issue of Nutrition and Cancer, researchers at Rutgers, The State University of New Jersey, studied the anticancer properties of d-mixed tocotrienol complex toward prostate cancer in the transgenic adenocarcinoma mouse prostate (TRAMP) mouse model.
The researchers selected TRAMP mice model because it bears close resemblance to the various stages of human prostate cancer such as progression of the disease from early prostatic intraepithelial neoplasia lesions to a more aggressive metastatic adenocarcinoma.
In the supplemented group, TRAMP mice were fed 0.1%, 0.3% or 1% Tocomin diet for 16 weeks. TRAMP mice in the positive control group and normal (wild-type) non-transgenic mice were fed regular diet for 16 weeks. Mice in all groups were aged 8 weeks old when the study began.
Throughout the study, all the mice were in good health condition with no significant change observed in body weights among mice fed Tocomin diet or normal diet.
However, the researchers observed significant reduction in the occurrence of prostate tumors in the Tocomin supplemented group compared to the control group. 38%, 33% and 22% of TRAMP mice in the 0.1%, 0.3% and 1% Tocomin diets, respectively, developed palpable tumors compared to 73% in the control group. There were significantly fewer number of high-grade neoplastic (PIN) lesions and higher number of low-grade PIN in the Tocomin group while about 75–80% of the control mice had high-grade PIN, 25–30% had low-grade PIN.
Further analyses revealed that Tocomin significantly increased the expression of proapoptotic proteins BAD, cleaved caspase 3, cdk inhibitors p21 and P27 while suppressing the expression of cyclins A and E, compared to control. Increased levels of p21 and p27 drive the cancer cells to apoptosis by recruiting capases and BAD.
Control mice demonstrated enhanced expression of cyclins that led to uncontrolled proliferation of cancer cells, which resulted in tumor formation.
The researchers concluded that Tocomin effectively suppresses the progression of high-grade prostatic neoplastic lesions to fully developed tumors, by regulating cell cycle processes and increasing the production of proapoptotic proteins that led to an overall suppression of tumor formation.
“It is exciting to learn of yet another chemopreventive potential of this tocotrienol complex against prostate cancer,” says WH Leong, Vice President, Carotech Inc., “Prostate cancer is the second most common male cancers in most developed nations. Throughout the whole world, close to one million men had been diagnosed with prostate cancer in 2008. The American Cancer Society estimated that for this year, about 217,000 new prostate cancer cases will be identified in US and 32,000 men will die of prostate cancer. These statistics are not favorable to most men.” WH Leong explained.
